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Engineering flax and hemp for an alternative to cotton
Abstract
Flax and hemp were the most important source for textile yarns until the 18th century. Since then cotton has taken over their role. The recent developments in plant genomics and the availability of microarray technology make it possible to better understand the complex relation between genes and fibre quality. This will lead to new targets for breeding and become the final break-through for alternative crops such as flax and hemp.
... In general, the fibres have a length from 5 to 55 mm and their diameter varies from 16 to 40 μm ). They are highly moisture absorbent, offer a good breathability and thermal insulation (Ebskamp, 2002) and have a superior UV resistance. Furthermore, it was found out that hemp fibres have anti-bacterial properties and a high absorbability of toxic gases (Jianchun, 2008). ...
... The higher the amount of lignin in the plant while harvesting, the lower is the fibre quality. A decreased lignin level therefore could lead to improved fibres, offering better comfortability through increased softness of the fibres (Ebskamp, 2002). As already mentioned before, farmers are driven by economic aspects to harvest the hemp plants when the seeds are ripe, since those generate the highest income for hemp cultivation. ...
... As outlined in this section, there are miscellaneous attempts to improve the performance of hemp fibres. Despite the molecular determination, chemical-physical methods, and the improvement by cultivation methods, researchers investigated in other chemical and enzymatic treatments for improved retting processes and for a facilitation of the decortication process, to decrease the extent of fibre damage during this process (Ebskamp, 2002). China, moreover, delved into another direction concerning hemp fibres. ...
The reason for this research is the minor prominence and application of hemp in the fashion industry. Focus is particularly put on the European market, but also has reference to global developments in the fashion as well as in the hemp industry. The main objective is to determine the major factors hampering hemp to be integrated in the textile apparel value chain, and to further give advice on how these bottlenecks could be solved in the long run. With the aid of a widely designed literature review and the collection of perceptions of experts working in the hemp industry, the goal of the research is approached. The literature review displays information about historical, industrial, agricultural and legal factors that affect the state of the art. Hemp fibre properties are presented and compared with those of cotton, to find out if modification is needed for greater success. Moreover, cultivation, processing and sustainability aspects are elaborated for both raw materials. Furthermore, the limited hemp fibre demand is pointed out from the fashion industry’s viewpoint to get a better understanding and create an overall picture about the main obstacles. The hemp industry’s opinions serve to gain insight in this branch, to find perceived threats and opportunities of the crop, and to further support the findings from the literature review. By that, the ecological as well as economical perspectives are taken to figure out the future potential for the European production of hemp for the fashion industry.
... Flax has been grown since ancient times as a source of seed oil and fiber (called as linen) [85]. Flax fibers are extracted from the stems through a process known as retting [86] and it was the major source of textile fibers prior to the widespread use of cotton [87]. Although the cotton fiber industries have been well-established, the quest for alternative sources of textile fibers has always been in place. ...
... In this regard, the excellent fiber properties of flax attract the attention of the textile industries (Table 1). Apart from being a raw material for the textile industry, flax fiber is also used in the production of paints, building materials, cosmetics, cars, aerospace, cigarette, papers, and medicines [87]. ...
Natural fibers have garnered considerable attention owing to their desirable textile properties and advantageous effects on human health. Nevertheless, natural fibers lag behind synthetic fibers in terms of both quality and yield, as these attributes are largely genetically determined. In this article, a comprehensive overview of the natural and synthetic fiber production landscape over the last 10 years is presented, with a particular focus on the role of scientific breeding techniques in improving fiber quality traits in key crops like cotton, hemp, ramie, and flax. Additionally, the article delves into cutting-edge genomics-assisted breeding techniques, including QTL mapping, genome-wide association studies, transgenesis, and genome editing, and their potential role in enhancing fiber quality traits in these crops. A user-friendly compendium of 11226 available QTLs and significant marker-trait associations derived from 136 studies, associated with diverse fiber quality traits in these crops is furnished. Furthermore, the potential applications of transcriptomics in these pivotal crops, elucidating the distinct genes implicated in augmenting fiber quality attributes are investigated. Additionally, information on 11257 candidate/characterized or cloned genes sourced from various studies, emphasizing their key role in the development of high-quality fiber crops is collated. Additionally, the review sheds light on the current progress of marker-assisted selection for fiber quality traits in each crop, providing detailed insights into improved cultivars released for different fiber crops. In conclusion, it is asserted that the application of modern breeding tools holds tremendous potential in catalyzing a transformative shift in the textile industry. KEY POINTS Natural fibers possess desirable properties, but they often lag behind synthetic fibers in terms of both quality and quantity. Genomic-assisted breeding has the potential to improve fiber quality traits in cotton, hemp, ramie, and flax. Utilizing available QTLs, marker-trait associations, and candidate genes can contribute to the development of superior fiber crops, underscoring the significance of advanced breeding tools.
... Although the abundant of synthetic fibre, cotton (Gossypium hirsutum L.) is still most popular and versatile textile fibre in world market . It is used for a variety of textile applications such as apparel fabric, upholstery, carpets and curtains, etc [40][41][42][43][44][45][46][47][48][49][50][51][52]. Cotton fibre is smoother, stiffer and straighter than hemp fibre [40][41][42][43][44][45][46][47][48][49][50][51][52]. ...
... It is used for a variety of textile applications such as apparel fabric, upholstery, carpets and curtains, etc [40][41][42][43][44][45][46][47][48][49][50][51][52]. Cotton fibre is smoother, stiffer and straighter than hemp fibre [40][41][42][43][44][45][46][47][48][49][50][51][52]. Cotton can be dyed easily and the color of dyed cotton often remains fast to repeated washings and to prolonged wear as well. ...
This review paper highlights the importance and role of hemp fibre in textile industries. In recent years, there has been a resurgence of interest in hemp as a sustainable and versatile textile fibre in fashion and textile industry. Hemp is a sustainable and environmental friendly crop that can provide valuable raw materials to a large number of industrial applications. Hemp fibre is very strong compared with other natural fibres such as cotton, flax and nettle. The cultivation of hemp has significantly less environmental impact compared to cotton. The industrial hemp contains primary and secondary fibres of which the primary fibres are utilisable for the textile end use. Hemp has been the mostly blended with cotton and synthetic fibres due to barriers in the industrial process of the production of full hemp-based textiles. Hemp clothing is stronger and more durable than cotton clothing and does not deform as easily. Apparel made from hemp merges easily with dyes and does not discolour easily. Hemp has outstanding antibacterial properties that surpass those of cotton and also any other natural fibre. Hemp textile fibre is hypoallergenic and has natural antimicrobial properties, making it an excellent choice for individuals with sensitive skin. However, despite its many benefits, hemp is still relatively expensive in India compared to other cellulosic fibres such as cotton, linen, and rayon etc. Hemp has a great cultural and historical value in India because it has been grown and used here for thousands of years. This cultural history can be conserved and honoured by using hemp in the fashion and textile business.
... A possible solution to reducing resources used in cotton cultivation and the related environmental impacts is the use of organic cotton or recycled cotton fiber. Some studies have encouraged the use of flax fiber (bast fiber) instead of cotton to reduce environmental impact ( BIO Deloitte and BVA, 2015 , La Rosa and Grammatikos, 2019, Ebskamp, 2002, Muzyczek, 2020. Among natural fibers, bast fibers such as flax fiber are considered sustainable and economically viable ( La Rosa and Grammatikos, 2019 ). ...
... flax) do have favorable properties. In view of the recent development of flax fiber, it may compete with cotton fiber ( Ebskamp, 2002 ). Recent advances in technology have been used to process natural bast fibers to produce new economically and environmentally viable fabrics ( La Rosa andGrammatikos, 2019 , Ebskamp, 2002 ). ...
The aim of this study is to evaluate the environmental impact of two apparel products imported to Australia using the life cycle assessment methodology. Within this framework, the impact improvement opportunities are also assessed. Impact improvement options used for this assessment have been selected based on areas where impact reduction can be made and there is available inventory data to quantify the impact reduction potentiality of these improvement options. Impact categories of climate change potential (CCP), acidification potential (AP), water depletion (WD) and agricultural land occupation (ALO) are used for this assessment. The study finds that for cotton T-shirts the largest part of CCP impact (56.52%) is caused by consumer use, and this is mainly generated from energy use during apparel care (51.63%), whereas for polyester jackets the production stage is the main contributor of CCP impact (65.52%), and this is mainly caused by fiber production (21.95%) and electricity use in textile processing (13.58%). The impacts of AP, ALO and WD are largely contributed by production activities. It is observed from this study that the use of recycled polyester, recycled cotton and organic cotton can significantly reduce the impact of all categories, and the use of flax fiber contributes to the reduction of AP, ALO and WD impacts. Impact reduction can be achieved by changing the spinning system, including efficient pattern-making processes, using a more energy-efficient front-loading washing machine, and by changing consumer care habits of their apparel. This study enhances the understanding of the significance of different impact improvement opportunities towards increasing sustainability throughout the life cycle of apparel.
... aksesuarlar %100 kenevir lifinden ve/veya kenevir lifi ile farklı oranlarda çeşitli liflerin karışımları ile üretilebilmektedir. Ayrıca kompozit malzeme üretiminde de kenevir lifi kullanılabilmekte olup, son yıllarda otomotiv sektöründe çeşitli kompozit malzemeler olarak ve inşaat sektöründe izolasyon malzemesi olarak kullanım alanı bulmaktadır [1][2][3][4][5][6]. ...
... Kenevir lifleri yüksek mukavemet, yüksek nem çekme, nefes alabilirlik kabiliyeti, boncuklanma oluşturmama, anti bakteriyellik, UV koruma, anti alerjik ve iyi elektrostatik özellik göstermesi ile katma değeri yüksek ürünlerin üretiminde tercih edilmektedir [2,3,6]. Bu liflerin yüzey özellikleri alkali işlemler ile geliştirilebilmektedir. % 6 Sodyum hidroksit ile 40 °C'de 24 saat, 1/20 oranında işlem gören kenevir lifi, kullanıldığı kompozit yapının mukavemetini yaklaşık %20 oranında arttırmaktadır [7]. ...
Kenevir lifi tarih boyunca tekstil materyallerinde doğal elyaf olarak kullanılmış, zaman içinde önemini kaybetmiştir. Ancak son yıllarda, tekstilde biyobozunurluğun ve sürdürülebilirliğin önem kazanması ile alternatif doğal liflerin önemi de oldukça artmıştır. Kenevir bitkisinin kontrollü ekiminin serbest bırakılması ile bu lifin tekstilde kullanım olanakları yeniden araştırılmaya başlanmıştır. Bu çalışmada, kenevir dokuma kumaşın enzimlerle ön işlem olanakları araştırılmıştır. NaOH, H2O2 ve α-amilaz, pektinaz, lakkaz enzimleri uygulanarak üç farklı yönteme göre ön terbiye sonrası kumaş performans özellikleri karşılaştırılmıştır. Yöntem 1’de amilaz ile haşılı sökülen kumaş, NaOH ile hidrofilleştirilip ardından H2O2 ile ağartılmıştır. Yöntem 2’de haşılı sökülen kumaş, pektinazla hidrofilleştirilip ardından H2O2 ile ağartılmıştır. Yöntem 3’de kumaş, Yöntem 2’ye göre hidrofilleştirilip ardından lakkazla işleme tabi tutulmuştur. Kumaşların hidrofiliteleri, renk koordinatları, sarılık indeksleri, mukavemetleri, uzamaları ve buruşmazlık açıları değerlendirilmiştir. En iyi hidrofilite (1,46 s) Yöntem 2 sonrası elde edilmiştir. Enzimatik işlemler sonrası, renklendirme öncesi uygun kumaş zemin renginin elde edilebilmesi için optimizasyon gerekliliği ortaya çıkmıştır. İşlemler kumaşların kopma mukavemetinde ve uzamasında önemli bir değişim meydana getirmemiştir. Yöntem 1’e göre işlem gören kumaşların en yüksek buruşmazlık açısına (78°) sahip olduğu görülmüştür. Sonuç olarak kenevir elyafın yakın gelecekte öneminin tekrar artacağı ve endüstriyel tekstil uygulamalarında kullanım potansiyelinin olduğu söylenebilir.
... Particularly in the field of fiber crop production, additional emphasis has been invested in agronomic aspects, such as breeding of new varieties, disease and lodging resistance, cultivation, and crop management. 55, 88,90,91 Fiber crop production efficiency has been and still is improving by the mechanization of soil tillage and harvesting, an optimized use of fertilizers, and the efficient use of herbicides and pesticides. 55 It can be expected that new bast fiber crop varieties will be generated in the future. ...
... Such new plant varieties will contain high-quality fibers that will be easier to extract. 91 However, plant fiber crops certainly have merit as an alternative crop, but they are not automatically sustainable. The modern, yield-oriented agricultural techniques for the production of fiber crops (especially cotton) require huge amounts of water, pesticides, fungicides, and herbicides. ...
Plant fiber crops belong to the earliest known cultivated plants. They were cultivated for fiber production and were extensively developed through breeding and selection according to the human needs and values. These fibers used to possess great agricultural importance for the production of textiles until the late 19th century. However, the production of cheap synthetic textile fibers nearly terminated the production of traditional fiber crops, especially in Western Europe and North America. The increasing environmental awareness, growing global waste problems, the continuously rising high crude oil prices motivated governments to increase the legislative pressure; see, for instance, the European Union End-of-Life Vehicles* as well as Waste Electrical and Electronic Equipment (WEEE) Directive.† This in turn prompted researchers, industry and farmers to develop concepts of environmental sustainability and reconsider renewable resources. As a result of new legislation, the composite and polymer manufacturers, the processing industry and end-users but also the local communities will need to move away from traditional materials. New strategies will have to be developed for environmentally and economically viable materials manufacturing and processing, but also reuse and recycling. Composites with moderate strength will perform for many noncritical structural applications in the automotive and electronic, but also for packaging, housing and building industry. Green composites made entirely from renewable agricultural resources could offer a unique alternative for these applications. Plant fibers will be used as the reinforcing phase in such composites. They offer a real alternative to the commonly used synthetic reinforcing fibers, such as carbon, glass or aramid, because of their low density, good mechanical properties, abundant availability and problem-free disposal. Farmers might benefit from fiber crops because of their quick turnaround time. Fiber crops often produce very long fibers. The energy consumption for fiber crop cultivation, harvesting and fiber separation is much lower than the energy needed to manufacture synthetic fibers. However, there are also some drawbacks related to the use of plant fibers as reinforcement for polymers. Restrictions for the successful exploitation are their high moisture absorption, low microbial resistance and low thermal stability. Further research is necessary to gain a better understanding to develop sustainable economically viable materials processes for composites and to design innovative products of common interests.
... Particularly in the field of fiber crop production, additional emphasis has been invested in agronomic aspects, such as breeding of new varieties, disease and lodging resistance, cultivation, and crop management. 55, 88,90,91 Fiber crop production efficiency has been and still is improving by the mechanization of soil tillage and harvesting, an optimized use of fertilizers, and the efficient use of herbicides and pesticides. 55 It can be expected that new bast fiber crop varieties will be generated in the future. ...
... Such new plant varieties will contain high-quality fibers that will be easier to extract. 91 However, plant fiber crops certainly have merit as an alternative crop, but they are not automatically sustainable. The modern, yield-oriented agricultural techniques for the production of fiber crops (especially cotton) require huge amounts of water, pesticides, fungicides, and herbicides. ...
A novel robust non-woven sisal fibre preform was manufactured using a papermaking process utilising nanosized bacterial cellulose (BC) as binder for the sisal fibres. It was found that BC provides significant mechanical strength to the sisal fibre preforms. This can be attributed to the high stiffness and strength of the BC network. Truly green non-woven fibre preform reinforced hierarchical composites were prepared by infusing the fibre preforms with acrylated epoxidised soybean oil (AESO) using vacuum assisted resin infusion, followed by thermal curing. Both the tensile and flexural properties of the hierarchical composites showed significant improvements over polyAESO and neat sisal fibre preform reinforced polyAESO. These results were corroborated by the thermo-mechanical behaviour of the (hierarchical) composites, which showed an increased storage modulus and enhanced fibre-matrix stress transfer. By using BC as binder for short sisal fibres, added benefits such as the high Young's modulus of BC, enhanced fibre-fibre and fibre-matrix stress transfer can be utilised in the resulting hierarchical composites.
... There is an increasing interest in ecological values and renewable materials, and products are increasingly chosen on the basis of their quality merits, including environmental quality (Lorch 1990). One reason for the promotion of bast fibres as an alternative to cotton is that flax and hemp can be grown in moderate climates and they require relatively low input to give high yields (Ebskamp 2002). The bast fibre plants offer one alternative for agricultural production, where the need to find non-food plants as alternatives to food plants is discussed. ...
... When a raw material of natural origin is used for industrial purposes, it enters into the sphere of quality concepts (Kajamaa 1985). Quality means all the features and properties which fulfil the given or supposed needs (Juran 1988, Salminen 1990, Ebskamp 2002. Fulfilling the needs means that the fibre must meet the requirements of the functions of the insulation (Table 7). ...
... Fibers like bamboo, [11][12][13] Tencel, 14,15 and flax, 16,17 which are more sustainable and environmentally friendly than conventional cotton, have started to be employed in apparel production in the last few years. 18 Industrial hemp fiber, which stands out and shines with its strong sustainable yield potential for the apparel sector, is highlighted as a substitution fiber in this study. ...
"Known for its sustainable properties, the usability of hemp instead of conventional cotton hybrid yarns for clothing was investigated by spinning hybrid ring yarns using conventional cotton, viscose-hemp, and organic cotton-viscose-hemp blends for the sheath and elastane and polyester (Lycra and T400) for the core in the yarn structure. Unevenness, yarn imperfections, hairiness, tenacity, and breaking elongation properties of the spun hybrid yarns were examined comparatively by statistical analysis methods. The findings revealed that sheath fiber type, number of components in the yarn structure, and blend ratio were influential factors on yarn quality. Using hemp fiber in the yarn structure slightly decreased the yarn properties, except for tenacity, in general. This situation was more visible in hybrid yarns, which have three different fibers in the sheath. Blending viscose and hemp fibers in the yarn sheath structure provided a synergetic effect, improving the weak properties of both fibers. These yarns had nearly the same tenacity values (from 12.98 to 15.47) as conventional cotton yarns (from 15.24 to 16.8), which could be explained by the fact that hemp fiber has a higher tenacity value (45 cN/tex) than other fibers. Moreover, these yarns had the highest elongation values (from 15.88 to 10.79) due to the good elongation properties of the viscose fibers (20%), compared to other sheath fibers. As a result, when the produced yarns were evaluated in terms of sustainability and performance, viscose-hemp-blended yarns had the optimum yarn properties."
... De hecho, algunos cultivos de Cannabis sp. se han utilizado como proveedores de cáñamo para la industria textil (4) , para la producción de biocombustibles (5) y como componente en la industria automotriz (6) . Además, algunos ganaderos utilizan semillas como aditivos en la alimentación animal (7) . ...
This study aimed to determine the concentration of CP, EE, NSC, fibers, TPC, CT, CBD, THC, in vitro digestibility of dry matter and rumen fermentation parameters of agroindustrial residues of Cannabis sativa L. from two extractive processes of cannabinoids, as a potential source of forage in ruminants feeding. The flower of Cannabis sativa was exposed to cold-press extraction (CPC) and alcoholic extraction (AEC) process; vegetative residues obtained after extractions were compared to raw flower as a control (RFC) using a completely randomized design and Tukey’s test for means comparison. Extractive processes decreased EE, TPC and cannabinoids (CBD and THC). Otherwise, fibers, NSC and digestibility, increased after the extractive processes in CPC and AEC. Similarly, in vitro degradability increased after both extractive processes above 120 % as well as latency period. Additionally, protozoa increased with CPC but no changes were observed in AEC. Likewise, no changes were observed in cellulolytic bacteria in CPC and AEC. However, total bacteria were reduced after both extractions. Moreover, N-ammonia in ruminal fermentations decreased with CPC and AEC whereas total volatile fatty acids increased. In addition, gas production increased above 75 % in CPC and AEC; however, no changes were observed in latency period. Furthermore, methane and CO2 production increased above 80 and 60 %, respectively for CPC and AEC; these augmentations are positively associated with improvements in the ruminal fermentations. In conclusions, the agroindustrial residue of Cannabis sativa L. obtained after the analyzed extractive processes may arise as a potential forage source in ruminants feeding.
... These fibre crops are more resilient, use less water and land, and can be harvested within 120 to 125 days (Singh et al. 2018). The hemicellulose component of these fibres contributes to their breathability and thermal insulation (Karimah et al. 2021, Ebskamp 2002. Jute and kenaf are ideal rotation crops due to their long taproot structure that helps retain topsoil while also replenishing soil quality due to the high carbon sequestration and natural leaf and root composting that regenerates vital elements in the soil (Singh et al. 2019). ...
Increasing demand for shopping and packaging carrier bags has given rise to various issues relating to its disposal as well as to the overall environmental footprint and sustainability of the packaging materials. This study assesses the carbon footprint and life cycle environmental impacts of the production, usage, and disposal of low density polyethylene (LDPE) and two natural fibre carrier bags (jute and kenaf). Life cycle assessment study was conducted of all inputs and outputs, aggregated in the form of resources used and environmental emissions, extending from the production of raw materials to the final disposal of the product. The carbon footprint and GHG emissions of jute and kenaf carrier bags were estimated using the CO2, N2O, and CH4 emissions coefficients of inputs. Research literature from life cycle impact assessment (LCIA) results was used to determine the effects of LDPE polyethylene packaging material. It was observed that the global warming potential (GWP) for the production of 1 kg of LDPE (100 micron) carrier bag (39.4 kg CO2eq) is more than 490 times higher than jute and kenaf carrier bags. In general, LDPE materials have the greatest impact on the carbon footprint and resource depletion. The LDPE material also has the highest impacts on indicators of terrestrial ecotoxicity, photochemical oxidation, acidification, and eutrophication as compared to jute and kenaf fibres. Since jute and kenaf are natural fibres, they sequester a substantial quantity of carbon during their agricultural stages. As a result, greenhouse gas (GHG) emission emissions of jute and kenaf were found to be negative. Popularising the use of jute and kenaf products as alternatives to plastic in industrialised countries would benefit the reduction of plastic waste and its negative environmental effects. Additional production of jute and kenaf fibre, which are already available in major bast fibre producing countries like India and Bangladesh, could meet the demand for fibre-based carrier bags.
... However, around the 18th century, cotton had become popular and had taken over the role as the principal fiber plant. Cotton fiber has a soft and comforting touch because cellulose of high crystallinity and purity compose the cell wall [35]. Now, the "cellulose gap", an excessively high demand for natural fiber not being met by cotton production, encourages textile manufacturers to seek substitutes for cotton [12,36]. ...
In the era of SDGs, useful plants which provide valuable industrial outputs and at the same time pose less impact on the environment should be explored. Hemp seems one of the most relevant gluten-free crop plants to meet such requirements. Its high nutritional value is comparable to soy. Moreover, almost the whole body of the hemp plant has a wide array of utility: industrial production of food, fiber, and construction materials. In view of environmental sustainability, hemp requires less pesticides or water in cultivation compared to cotton, a representative fiber plant. This short review investigates hemp’s sustainability as a plant as well as its utility value as a highly nutritional material in the food industry. Recent application research of hemp protein in food processing includes plant milk, emulsifiers, fortification of gluten-free bread, plant-based meat production, as well as membrane formation. These studies have revealed distinctive properties of hemp protein, especially in relation to disulfide (S-S)/sulfhydryl (-SH)-mediated interactions with protein from other sources. While its cultivation area and industrial use were limited for a while over confusion with marijuana, the market for industrial hemp is growing rapidly because it has been highly reevaluated in multiple areas of industry. Conclusively, with its sustainability as a plant as well as its distinctive useful property of the seed protein, hemp has promising value in the development of new foods.
... Bundan dolayı yalıtım malzemesi, kağıt, tekstil gibi sahalarda sağlıklı bir ürün elde etme imkanı sunmaktadır. Otomotiv sektöründe bulunan Mercedes-Benz şirketi otomobil üretirken otomobillerin birçok yerinde doğal lifleri 1992' den beri kullanmaktadır (9,10). Otomobillerin 20'den fazla kısmında kullanılmakla birlikte özellikle kapı ve koltuk panellerinde, kenevir lifinden üretilen kompozit kullanılır. ...
Kenevir çok eski zamanlardan beri kullanılan tek yıllık otsu bir bitkidir. Çıkış yeri Orta
Asya olarak kabul edilmektedir. Daha sonra diğer ülkelere de yayılarak hem ilaç olarak hem de insanlar için gerekli olan ip-kumaş gibi malzemelerin yapımında M.Ö. 3200’lü yıllardan 1950’lere kadar dünya genelinde çok geniş bir coğrafyada kullanılmıştır. Bunun yanında uyuşturucu özellikleri de olduğundan dolayı insanlardan tarafından sorunlu bir bitki olarak görülüp 1950’lerden sonra hükümetler yasalar çıkararak kenevir ekimini ve kullanımını kısıtlamışlardır. Bunun üzerine kenevir ekimi dünya genelinde olduğu gibi Türkiye’de de hızla azalmıştır. 2000’li yıllardan sonra ise kenevir üzerinde yapılan araştırmalar sonucunda uyuşturucu olarak etki eden bileşiğin Tetrahidrocannabinol (THC) olduğu tespit edilmiştir. Araştırmalara devam edilerek bu bileşiğin bitkideki oranı azaltılarak kenevirin endüstriyel olarak kullanılabileceği ortaya konulmuştur. Bundan sonra şirketler endüstriyel kenevir olarak kullanılabilecek psikoaktif olmayan kenevir türüne yönelmişler ve günümüzde bu türün ekim alanları artmaktadır. Hükümetler de bu konudaki yasalarını tekrar düzenlemektedirler ve başta ilaç yapımı olmak üzere çeşitli alanlarda psikoaktif
olmayan kenevirin kullanılmasına belli oranda izin vermektedirler.
Kenevirin en önemli özelliklerinden birisi geri dönüşümü olması ve kenevirden elde
edilen ürünlerin biyobuzunur olarak çevre dostu olmalarıdır. Çünkü kenevir doğal bir
üründür. Dolayısıyla onun lif vb. kısımları kullanılarak üretilen ürünler de doğal ve çevreci bir özelliğe sahip olmaktadırlar. Kenevirin çevreci özelliklerinin başında biyobozunur özelliğinin olması, yetiştirilmesi sırasında çok daha az kimyasal ilaç ve gübreye ihtiyaç duyması gelmektedir. Ayrıca yapraklarının çok olması sebebiyle birim alandan daha çok oksijen üretimine katkıda bulunmaktadır. Kenevir ürünleri atık duruma geldiğinde doğada bozunur bir kimyasal yapıya sahiptir. Yapay liften yapılan ürünlerin atıkları doğada yıllarca bozunmadan kaldığı halde kenevir lifinden yapılan ürün atıkları bozunur özelliğiyle sağlıklı bir çevreye katkıda bulunmaktadır.
Kenevirin dikkat çeken özelliklerinden birisi de çok değişik endüstri alanlarında binlerce çeşit ürün imalatında kullanılır olmasıdır. Bunun sebebi doğal olması, geri dönüşümünün olup biyobozunur yapıya sahip olması, dayanıklı olması, aşınmaya karşı dirençli olması, nem çekme özelliğinin olması, izolasyon sağlaması gibi üstün özelliklerinin olmasıdır. İlaç yapımında, insan ve hayvan besin maddeleri üretiminde, inşaat alanında duvar ve çatı malzemeleri yapımında, iplik, halat, urgan, kumaş yapımında, giyim ve aksesuar malzemeleri üretiminde, plastik malzemeleri üretiminde, kağıt-karton yapımında, biyokütle-biyodizel üretiminde, otomobillerin kaporta vb. parçalarının yapımında, kozmetik ürünleri yapımında, makine parçaları üretiminde kenevir kullanılabilir. Sonuç olarak, endüstriyel olarak kullanılabilecek uyuşturucu olmayan kenevirin üretiminin artırılarak sahip olduğu potansiyelin endüstri sektörlerinde değerlendirilmesi özellikle çevreyi koruma açısından, insan beslenmesi ve sağlığı açısından, ayrıca da dayanıklı ve doğal tüketim malzemeleri açısından yararlı olacaktır.
... Some other drawbacks of cotton are the high amount of water consumed during cultivation, the necessity of using pesticides and the proper conditions for harvest (can only be grown in temperate-hot climates) [4,5]. For these reasons, the use of alternative natural fibers such as hemp can be blended with cotton to achieve similar or even better properties as pristine cotton in the final product will contribute to an increase in the sustainability of the textile process [6,7]. ...
The objective of this work was to assess the possibility of dyeing a substrate composed of non-textile industrial hemp using natural dyes from common madder (Rubia Tinctorum L.) and calendula (Calendula Officialis) and tannin and alum as mordants. The substrate used for the dyeing had a 25/75 hemp/cotton composition. The hemp raw material is an agricultural by-product that was subjected to mechanical and chemical treatments in order to cottonize the fibers, blend them with cotton, and thus obtain first 40-tex open-end yarns and then a knitted fabric. The latter was subjected to different dyeing conditions by varying the dye, mordant, and method for its application, type of water, and rinsing after dyeing. Measurements of the difference (ΔE) and intensity (K/S) of color and fastness to washing and rubbing were carried out. The results showed that dyeing of a non-textile residual hemp substrate is possible, and that calendula is a good option for dyeing it with tap water, tannin-alum set in a meta-mordanting process, and rinsing after 24 h. In this way, a contribution has been made to the circular economy of the textile industry through the use of more sustainable sources and products.
... Now equation (5) can be simplified further, and for a given shape parameter (a) and scale parameter (b), the average Weibull tensile strength, r avg , can be determined using equation (6). Similarly, the average Weibull tensile modulus of cattail fiber, E avg is determined: ...
Biomass fibers are being widely investigated for industrial applications as an alternative to synthetic fibers using a standard humidity condition. In this study, the mechanical properties of two waste biomass fibers – canola and cattail – have been investigated when subjected to different environmental conditions, fiber length, and type of estimators used during analysis. The effect of different environmental conditions and structural variations were investigated by measuring the tensile properties after exposing them to eight different relative humidity conditions using a fixed fiber length of 25 mm. Further investigation was conducted using fiber lengths of 25, 35 and 45 mm using the most conservative relative humidity condition. The data were analyzed by a Weibull distribution model using four different estimators. The results revealed that Weibull strength ( σ avg ) and modulus (E avg ) closely followed experimental values for cattail and canola fibers. The different relative humidity conditions and fiber lengths resulted in different Weibull parameters with 11% relative humidity and the mean rank estimator predicted the most conservative tensile strength for both waste biomass fibers. The experimental and characteristic Weibull strength decreased when fiber gauge length increased from 25 to 45 mm. The tensile strength and modulus of both waste biomass fibers at 50% reliability lie within the range of average experimental values. However, these values are reduced to 155 MPa (strength) and 20 GPa (modulus) for cattail fiber at 90% reliability. The survival probability of the tensile strength and modulus were found to be the highest at 75% and 100% relative humidity for cattail and canola fibers, respectively.
... 7−9 This has led to an effort to replace cotton with bast fiber crops such as flax and hemp that do not require the same maintenance. 10,11 Hemp (Cannabis Sativa) is a herbaceous crop that can be grown in most climates, while cotton is limited to cultivation in subtropical climate zones. Hemp has recently gained attention for natural fiber production due to both agricultural and sustainability reasons. ...
Despite the increased use of hemp fiber, negligible attention has been given to upgrade the hemp hurd, which constitutes up to 70 wt % of the hemp stalk and is currently considered a low-value byproduct. In this work, valorization of hemp hurd was performed by reductive catalytic fractionation (RCF) in the presence of a metal catalyst. We found an unexpectedly high yield of monophenolic compounds (38.3 wt %) corresponding to above 95% of the theoretical maximum yield. The high yield is explained by both a thin cell wall and high S-lignin content. In addition, organosolv pulping was performed to generate a pulp that was bleached to produce dissolving-grade pulp suitable for textile fiber production (viscosity, 898 mL/g; ISO-brightness, 90.2%) and nanocellulose. Thus, we have demonstrated a novel value chain from a low-value side stream of hemp fiber manufacture that has the potential to increase textile fiber production with 100% yield and also give bio-oil for green chemicals.
... 1). В ряде исследований показано, что высота растений льна-долгунца в зависимости от сортовых особенностей и условий выращивания варьирует в достаточно широком диапазоне (от 70 до 125 см), а при благоприятных условиях может достигать 130-140 см [15,16]. ...
... Hemp can produce paper of superior quality to wood paper, with an added benefit of reducing deforestation as a result [75]. Hemp could rejoin the textiles industry in the coming years, since cotton production can only be accomplished in sub-tropical environments and requires large amounts of water, while hemp can be grown virtually anywhere with little water if any [76]. Hemp has been shown to be economically competitive with cotton, providing a sustainable alternative that does not require insecticides nor pesticides, and requires significantly less land than cotton [77]. ...
Climate change from carbon emissions and rising energy demands poses a serious threat to global sustainability. This issue is particularly noticeable in Canada where per capita energy demands are high and fossil fuels are used. Industrial hemp can be used for bioenergy production as an alternative to fossil fuels to capture and utilize carbon, with applications in various markets at high values. Despite this, industrial hemp has faced legal barriers that have hampered its viability. This review describes industrial hemp, its status in global markets, its performance as bioenergy feedstock, and potential in Canada, so research can target gaps in available knowledge. Numerous bioenergy applications for industrial hemp exist; the production of bioethanol and biodiesel from industrial hemp has strong potential to reduce greenhouse gas emissions and improve the Canadian economy. The current study found that industrial hemp can compete with many energy crops in global markets as a feedstock for many bioenergy products with solid hemp yielding 100 GJ/ha/y, allowing for economical emissions reductions for example in coal/biochar blends that can reduce emissions by 10%, and in co-production of bioethanol and grain, generating $2632/ha/y. This work also suggests industrial hemp has unique potential for growth in Canada, though processing facilities are severely lacking, and hemp growing has some negative environmental impacts related to fertilizer use. Responsible growth could be realized through incentivizing or subsidizing processing facility investment, implementing co-production where possible, and funding research to improve conversion, harvesting and polygeneration processes.
... Besides, it can also be used for bio-remediation purposes of polluted lands (Struik et al., 2000;Amaducci et al., 2008;van den Broeck et al., 2008;Amaducci and Gusovius, 2010). This multi-purpose crop is, apart from being a valuable source of cannabinoids and oils (Salentijn et al., 2015), an alternative and more sustainable source of fibers relative to water and nutrient demanding crops, (e.g., cotton) and to non-renewable glass and fossil-based fibers (Ebskamp, 2002;van der Werf and Turunen, 2008;Amaducci and Gusovius, 2010). Despite the large interest in hemp, it is a relatively poorly developed crop. ...
Hemp (Cannabis sativa L.) is a bast-fiber crop with a great potential in the emerging bio-based economy. Yet, hemp breeding for fiber quality is restricted and that is mainly due to the limited knowledge of the genetic architecture of its fiber quality. A panel of 123 hemp accessions, with large phenotypic variability, was used to study the genetic basis of seven cell wall and bast fiber traits relevant to fiber quality. These traits showed large genetic variance components and high values of broad sense heritability in this hemp panel, as concluded from the phenotypic evaluation across three test locations with contrasting environments. The hemp panel was genotyped using restriction site associated DNA sequencing (RAD-seq). Subsequently, a large set (> 600,000) of selected genome-wide single nucleotide polymorphism (SNP) markers was used for a genome-wide association study (GWAS) approach to get insights into quantitative trait loci (QTLs) controlling fiber quality traits. In absence of a complete hemp genome sequence, identification of QTLs was based on the following characteristics: (i) association level to traits, (ii) fraction of explained trait variance, (iii) collinearity between QTLs, and (iv) detection across different environments. Using this approach, 16 QTLs were identified across locations for different fiber quality traits, including contents of glucose, glucuronic acid, mannose, xylose, lignin, and bast fiber content. Among them, six were found across the three environments. The genetic markers composing the QTLs that are common across locations are valuable tools to develop novel genotypes of hemp with improved fiber quality. Underneath the QTLs, 12 candidate genes were identified which are likely to be involved in the biosynthesis and modification of monosaccharides, polysaccharides, and lignin. These candidate genes were suggested to play an important role in determining fiber quality in hemp. This study provides new insights into the genetic architecture of fiber traits, identifies QTLs and candidate genes that form the basis for molecular breeding for high fiber quality hemp cultivars.
... The crop is competitive with weeds and rarely experiences devastating insect damage or disease outbreaks [19]. As a result, hemp has relatively low input requirements for pesticides and herbicides [18,24]. However, there is potential for greater input requirements should hemp production be pursued more intensively [13,16]. ...
Hemp’s reemergence in the United States’ economy presents an opportunity for a new category of sustainable product choice for consumers. This study fills a gap in knowledge about which consumers are currently aware of or choosing hemp products using the theory of choice alternatives and a statistically representative survey from a top ten hemp producing US state. Findings reveal high levels of consumer awareness and consideration of hemp products in general and a smaller evoked/choice set. Cannabidiol products appear most often in our sample’s choice set; we examined these specifically. Other hemp products also appear, including clothing and textile, personal care, building material, and food products. Bivariate logistic regression results show that older respondents are more likely to be in the unaware set for hemp products in general and for cannabidiol products. Politically liberal respondents are more likely to be in the evoked/choice set for hemp products in general and for cannabidiol products. No demographic variables are significantly associated with being in the consideration set for hemp products in general. Younger and more educated respondents are more likely to consider cannabidiol products. As hemp represents a nascent but growing market, this study provides a baseline from which to build understanding of consumer choice alternatives.
... Characterization of hemp fiber quality, including stem morphology and cell wall composition and structure, is the first step toward breeding for high yielding varieties with better fiber quality. Such varieties, that are more amenable to processing, positions hemp as a competitive alternative to poor sustainable fiber crops such as cotton (Ebskamp, 2002;van der Werf and Turunen, 2008;Amaducci and Gusovius, 2010). ...
The growing demands for sustainable fibers have stimulated the study of genetic diversity in the quality of hemp fiber (Cannabis sativa L.). Nevertheless, the lack of high-throughput phenotyping methods that are suited for the analysis of hemp fiber, hampers the analysis of many accessions, and consequently the breeding for this complex trait. In the present report, we developed and optimized the throughput of five methods to study the diversity in hemp fiber quality including cell wall extraction, biochemical composition of cell wall polysaccharides, quantification of lignin, quantification of crystalline polysaccharides and morphology of the stems. Six hemp accessions contrasting for cell wall properties were used to assess the throughput and suitability of these methods for genetic studies. The methods presented revealed to be highly repeatable, with low coefficients of variation between technical replicates. With these methods we were able to detect significant phenotypic variation in cell wall composition and stem morphology between the six accessions. In addition, the throughput of the methods has been upgraded to a level that enables their use for phenotyping cell wall traits in breeding programs. The cell wall extraction was optimized to extract enough material for the complete characterization of the cell wall of hemp while reducing the time for the entire analysis. The throughput of the stem morphological analysis was improved by decreasing the timing of fixation, infiltration, and embedding of mature and dry hemp stems. Notwithstanding, our methods already have the potential to phenotype large number of accessions in a relatively short period of time. Our methods will enable exploration of genetic diversity of fiber quality and will contribute to the development of new hemp varieties with advanced quality of fibers.
... Its main characteristics are: (1) a very significant length (from a few hundred micrometers up for a number of centimetres) with the ratio between the length and diameter of cells ranging from 50 to 2000 or even more; (2) unusually thick cell wall, reaching up to 15 μm; and (3) mechanical function [4], [5], [9], [10], [11]. Phloem fibre plants, including marijuana (Cannabis sativa), has been used by humans since ancient times and now has a wide range of applications, both traditional and modern [12], [13], [14], [15]. Long and strong ramie fibres have a rich history of use for the production of ropes, paper, and textiles. ...
The present research was conducted on five clones of ramie (Boehmeria nivea L.Gaud.) found in West Sumatra and several other clones from Java. The research objective was to compare the growth, the number of fibers per bundles, length and the time until fibers are matured enough for harvesting. The ramie planting was done in Andalas University's Padang experimental field station from June to October 2016. Microscopic investigation and fiber analysis were carried out in the laboratory of Plant Development and Structure, Department of Biology, Faculty of Mathematics and Natural Science, Andalas University, Padang, Indonesia. The clones investigated were Bandung A, Indochina, Lembang A, Padang 3, and Ramindo. The numbers of fibers per fiber bundle were highest in the Ramindo clone at 69 cell/bundle and the least in Bandung A clone at 40 cell/bundle. The type of fiber was 48% type I, 36% type II and 16% type III. The patterns of fiber-shape in each fiber bundle from the cambium to the outside increases in diameter with the centre being dominantly type I, the middle region type II, and the outer region type III. The length of fiber found in the present study (longest 70 mm) is shorter than in previous reports. Length, diameter, and thickness of cell wall of clone ramie fiber cells grew at similar rates throughout the maturation process. Fastest fiber growth was obtained from Padang 3 clones at 132 μm/day, while the slowest was in Ramindo clones at 48 μm/day. The fastest fiber growth for all clones occurred at 2-3 weeks of age. Based on fiber growth, Padang clones should be harvested after six weeks, clones of Indochina, Lembang A, and Ramindo harvested after eight weeks and Lembang A clone after the eighth week. This is sooner than harvesting based on morphological characteristics, which would be between the age of 10-11 weeks. The clones of Padang A were considered superior to the other clones.
... Hemp plant (Cannabis sativa L.) has recently drawn much interest in the construction sector for the manufacture of bio-based composite structures [1][2][3][4]. The plant does not require a lot of water to grow, is easy to harvest in moderate climates [5], and exhibits a range of interesting and useful properties. The woody core of the plant, usually named hemp shiv, is very porous with a low bulk density [4], which makes it a valuable candidate for use as an insulation material for both acoustic [6,7] and thermal [8][9][10][11] applications. ...
New bio-materials have recently gained interest for use in insulation panels in walls,
but wider adoption by the building industry is hindered by their intrinsic properties. The fact that
such materials are mainly composed of cellulose makes them combustible, and their hydrophilic
surface presents a high water uptake, which would lead to faster biodegradation. A hydrophobic
treatment with silica particles was successfully synthesised via Stöber process, characterised,
and deposited on hemp shiv. The surface of hemp shiv coated several times with 45 and 120 nm
particles were uniformly covered, as well as extensively water repellent. Those samples could
withstand in humidity chamber without loss of their hydrophobic property and no sign of mould
growth after 72 h of exposure.
... Plant phloem fibers, including those of hemp (Cannabis sativa L.), have been used by humans since ancient times and currently have numerous applications, both traditional and modern (Reichert 1994;Ebskamp, 2002;Thygesen et al., 2006;John and Thomas, 2008;Snegireva et al., 2015). The use of hemp fiber for pulp and paper production dates back more than 2,000 years. ...
The objective of this study was to characterize the properties of pulp and paper produced from hemp (Cannabis sativa L.) using kraft-sodium borohydride (NaBH 4). The Suitability of the fiber for pulp and paper production was examined, and some chemical, physical and optical properties of pulps and papers were investigated. Twelve different cooking experiments were performed on the hemp, and effects of NaBH 4 charge and active alkali ratio were determined. The best pulp yield, 77.94%, was found in the cooking experiment with 0.7% NaBH 4 and 19% active alkali. The twelfth cooking, with 0.7% NaBH 4 , gave the best yield (77.94%), an increase of about 11.36% compared with cooking with no NaBH 4. Also, Kappa numbers of the pulps were decreased; pulp viscosities were increased by adding NaBH 4. The physical and optical properties of the papers were also examined and it was observed that these properties were improved by adding NaBH 4 .
... The renewed interest in C. sativa as a multi-purpose crop has been the main driving force for the application of advanced technologies on this species. For example, using high-throughput profiling technologies such as microarrays, the gene expression during secondary cell wall formation has been studied in hemp [65]. Hence, this dubious species (plant) will continue to make an impact on human societies in the future. ...
New crops are gradually establishing along with cultivation systems to reduce reliance on depleting fossil fuel reserves and sustain better adaptation to climate change. These biological assets could be efficiently exploited as bioenergy feedstocks. Bioenergy crops are versatile renewable sources with the potential to alternatively contribute on a daily basis towards the coverage of modern society’s energy demands. Biotechnology may facilitate the breeding of elite energy crop genotypes, better suited for bio-processing and subsequent use that will improve efficiency, further reduce costs, and enhance the environmental benefits of biofuels. Innovative molecular techniques may improve a broad range of important features including biomass yield, product quality and resistance to biotic factors like pests or microbial diseases or environmental cues such as drought, salinity, freezing injury or heat shock. The current review intends to assess the capacity of biotechnological applications to develop a beneficial bioenergy pipeline extending from feedstock development to sustainable biofuel production and provide examples of the current state of the art on future energy crops.
... The fibre bundles are 30-90 cm in length and 5-17 mm in diameter. Ebskamp (2002) describes the processing of hemp and flax fibre bundles and proposes that fibre quality can be improved by controlled chemical or enzymatic treatment during retting and an improved understanding of the genes involved in cell wall metabolism. The use of cDNA microarrays to study secondary cell wall formation in hemp and flax has identified candidate genes which enhance mechanical properties of the fibre bundles or facilitate their extraction. ...
The structure and properties of plant fibres are reviewed with emphasis on the deposition of cellulose microfibrils in the plant cell wall and the effect of microfibril angle on mechanical properties such as strength and stiffness. The worldwide production of cotton fibres for textile applications far exceeds that of other plant fibres, hence the structure of cotton is reviewed in detail. Plant fibre bundles such as sisal, hemp, jute and kenaf are finding new uses in structural applications in the automotive and construction industries and a significant proportion of the chapter is devoted to these industrial fibres. New developments in understanding structure-property relationships are continuously appearing in the literature and natural fibres have a strong part to play in a sustainable future.
... Its major characteristics are: (i) a very significant length (from several hundreds of micrometres up to many centimetres) with the ratio between cell length and diameter ranging from 50 to 2000 or even more; (ii) an extraordinarily thick cell wall, reaching up to 15 mm; and (iii) mechanical function as the major one (Esau 1977;Fahn 1990;van Dam and Gorshkova 2003;Gorshkova et al. 2012). Plant phloem fibres, including those of hemp (Cannabis sativa), have been used by humans since ancient times and currently have numerous applications, both traditional and modern (Reichert 1994;Ebskamp 2002;Thygesen et al. 2006;John and Thomas 2008). The long and strong hemp fibres have a rich history of use for the production of ropes, paper and textiles. ...
Plant fibres -cells with important mechanical functions and a widely used raw material - are usually identified in microscopic sections only after reaching a significant length or after developing a thickened cell wall. We characterized the early developmental stages of hemp (Cannabis sativa) stem phloem fibres, both primary (originating from the procambium) and secondary (originating in the cambium), when they still had only a primary cell wall. We gave a major emphasis to the role of intrusive elongation, the specific type of plant cell growth, by which fibres commonly attain large cell length. We could identify primary phloem fibres at a distance of only 1.2-1.5 mm from the shoot apical meristem when they grew symplastically with the surrounding tissues. 0.5 mm more basal, fibres began their intrusive elongation, which led to a sharp increase in fibre numbers visible within the stem cross-sections. The intrusive elongation of primary phloem fibres was completed within the several distal centimeters of the growing stem, before the onset of their secondary cell wall formation. The formation of secondary phloem fibres started long after the beginning of secondary xylem formation. Our data indicate that only a small portion of the fusiform cambial initials (<10%) give rise directly or via their derivatives to secondary phloem fibres. The key determinant of final bundle structure, both for primary and secondary phloem fibres, is intrusive growth. Through bi-directional elongation, fibres join other fibres initiated individually in other stem levels, thus forming the bundles. Our results provide the specific developmental basis for further biochemical and molecular-genetic studies of phloem fibre development in hemp, but may be applied to many other species.
Published by Oxford University Press on behalf of the Annals of Botany Company.
... Common application(s) are very much useful for better understanding of the molecular processes associated with the development of the bast fibre cells of flax stems (Ebskamp, 2002). Lipid transfer proteins (LTPs) and arabinogalactan proteins (AGP) transcripts were found well-correlated with stem segments during cell wall thickening phase of phloem fibre development; and chitinases, βgalactosidases, AGP, and LTPs were among the interesting transcripts enriched in specific stages of the developing stem in flax (Roach and Deyholos, 2007). ...
About 95 % of Jute and Allied Fibers (JAFs) are produced by small scale farmers in Indo-China, south and southeast Asia. Majority of the high yielding varieties of JAF crops such as jute, kenaf and mesta have been developed so far using traditional breeding methods. However, serious limitations of the traditional approaches in
developing new cultivars have urged the necessity of adapting to molecular techniques for the improvements of
JAFs. This review aims in investigating the current status and future prospects of Genomic and Proteomic
approaches in the improvement of JAF crops.
... Two major obstacles to a modern production line have been eliminated by breeding in the last decades: the change from dioecious to monoecious plant types and a considerable reduction of tetrahydrocannabinol (THC). To launch hemp successfully, THC levels must be kept low and new varieties must be monoecious with improved yield, quality of fibres and the composition of the cellulose (Ebskamp 2002, Ranalli 2004. ...
Today, food security depends on very few major grain crops, actually an outcome of breeding success and globalization. This will not change in the near future. But action must be taken to stop the unprecedented pace of the erosion of biodiversity on arable fields; this is a prerequisite to ensure robust cropping systems as well as complementary food production for coming generations. Although this has been discussed for decades, little progress has been made. Most underutilized crops are no longer suitable for today’s agriculture. Success can be achieved only by planning long‐term breeding programmes instead of screening underutilized crops again and again. This cannot be realized, however, by market‐driven private breeders. State funding is mandatory to launch a programme of a set of well‐chosen crops. Guidelines are provided, based on case examples from cool temperate regions, where promising crops undergo stepwise selection process. In Europe, a programme could be established in the frame of a virtual institute, wisely investing a small part of the direct payments that go to farmers today, thereby safeguarding their future.
... The importance of this latter point is emphasized by efforts by the U.S. Department of Agriculture and the US Food and Drug Administration to promote eating omega-3 fatty acids (Przybyla-Wilkes 2007). Ebskamp (2002) designated potential improvements for increasing fiber strength, softness, and hydrophobicity along with increasing yield and processing efficiency. Wrobel et al. (2004) indicate that the thermoplastic Poly-b-hydroxybutyrate (PHB) can be produced within the lumen of transgenic flax fibers, thus increasing its tensile strength. ...
a of intense interest. Production of these fibers, furthermore, can add to farmer incomes and promote agricultural sustainability. Flax (Linum usitatissimum L.), which has been used for thousands of years, is unparalleled in supplying natural fibers for industrial applications as diverse as textiles and paper, providing high value linseed and fiber from a single plant, and maintaining sustainable agriculture in temperate and subtropical climates for summer or winter production, respectively. Flax production is environmentally responsible with no insecticides and low herbicides usage, good erosion control, and low fertilizer requirements. The bast fibers (3,000 times longer than its diameter) are produced in the outer regions of the stem, having a fiber content of ~25%. Industrial advantages for natural fibers are a lower cost, low density, biodegradability, relatively high strength, low abrasiveness, abundance, renewability, non-hazardous nature, recyclability, and low equipment requirements. As a value-added replacement for glass fiber from a renewable resource,flax fiber is recyclable, biodegradable, and sustainable for the economy, ecology, and society. Stems of flax, as well as other bast plants, require retting to separate fiber to separate fiber from non-fiber components and rigorous mechanical cleaning to obtain industrial-grade fibers. As a natural agricultural product, flax's chemical and physical properties, which influence fiber production, processing, and utilization, cannot be completely controllled. Consequently, Consequently, fiber processing and use in composites are affected by variables such as length, uniformity, strength, toughness, fineness, surface constituents, surface characteristics, and contaminants. One of the main concerns for the composite and other industries in incorporating natural fibers, such as flax, into production parts is the fiber variability resulting from crop diversity, retting quality, and different processing techniques. Standardized methods to assess flax fiber properties, therefore, are needed to maintain quality from crop to crop and provide a means to grade fibers for processing efficiency and applications.
In this study, it is aimed to provide alternative fibers to cotton with enhanced comfort level, environmentally friendly and color‐enriched in the cellulosic knitted fabric field. For this purpose, in addition to 100% cotton, 100% flax, 100% hemp yarns, knitted fabrics were produced from 70% cotton / 30% flax and 70% cotton / 30% hemp yarns. First of all, the properties of yarns such as tenacity, elongation at break, yarn unevenness, thin places, thick places and neps were examined comparatively. Then, pique fabrics were produced from these yarns and dyed with a reactive dye to a selected color. Afterwards, physical (weight, wale/course density), mechanical (bursting strength, pilling, abrasion resistance) and comfort (air permeability and water vapor permeability) properties of all fabric samples, both in raw form and after dyeing&finishing processes, were compared. Furthermore, dyeing properties (color, dye‐uptake, dyeing levelness, fastness) of fabric samples were also investigated. The dye uptake (%) values of the yarns decrease in the order of cotton > cotton/hemp > cotton/linen > hemp > linen. However, fastness values of dyed fabrics were nearly identical. Physical and mechanical properties of fabrics were very similar, while the air permeability of the fabrics decrease in the order of Hemp > Linen > Cotton/Hemp > Cotton/Linen > Cotton. As a result of the study, it has been achieved to produce knitted fabrics with superior performance characteristics (dyeability, comfort, etc.) from yarns produced via blending natural cellulosic fibers (flax and hemp) with certain proportions of cotton fibers, which contribute to sustainable production.
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Composite parts, used in transportation industries, are manufactured using VARTM (Vacuum Assisted Resin Transfer Molding) and glass fiber non-woven mats that are optimized for impregnation, fiber volume fraction (Vf), and composite properties. However, such optimized non-woven mats are commercially not available for natural fibers such as hemp and flax. Fahimian (2013) has developed the knowledge on the effect of areal density (weight per unit area), needle punching used to bind the fibers together, and the pressure applied during manufacturing, on composite properties. Similar studies on flax fibers is not available. Such studies on Cattail fibers, with comparable properties and abundance, are lacking. Hence, the goal of this thesis to generate this knowledge and do a comparative evaluation of flax, cattail, and hemp fibers and their composites. The mat permeability as well as tensile strength and modulus of needle-punched (0-72P) flax composites, manufactured using VARTM pressure as well as compression molding pressures (subsequent to VARTM molding), were measured and evaluated. Similar studies were repeated on 50% Flax-50% hemp fiber mat. Cattail fibers were extracted from cattail leaf using alkali retting, characterized for properties, and used to manufacture 0-P mat. This was subsequently used to test for permeability as well as manufacture composites for mechanical testing. The results from these studies as well as that for hemp fiber (generated by Fahimian (2013)) were used in comparative evaluation of the three fibers as reinforcement in composites.
It was found that the Vf of flax mats changes with punch density that affects the permeability. Vf in flax mat composite dictates the modulus and strength which is a function of consolidation behavior that varies with punch density and pressure. Despite having similar tensile strength in all three fibers, cattail fibers possess higher specific strength than flax and hemp due to lower density values of cattail fiber; however, modulus and specific modulus increases as follows (Eflax< Ecattail<Ehemp); it should be noted that the weight of the composite part decreases with increase in specific properties of the fiber. The transverse permeability of cattail fiber mat is the highest, followed by hemp fiber mat and the flax fiber mat’s permeability was the least. At VARTM pressure (101 kPa) the properties of composites with three fibers are similar.
Due to the limited volumes of conventional sources of cellulose (cotton and wood), research centered on producing the most competitive science-driven products – cellulose nitrates – from new, domestic, easily renewable feedstocks is extremely relevant. The review of scientific literature corroborates the lack of data on the feasibility to obtain cellulose nitrates from Miscanthus, except for the authors’ publications. Here we suggest a tree-like industrial crop, Miscanthus var. KAMIS, growing with an yield of up to 20 t/ha a year on industrial plantations in Kaliningradskaya, Kaluzhskaya and Yaroslavskaya Oblasts and in Primorskiy Krai. A pulp sample derived from Miscanthus var. KAMIS by the nitric-acid process exhibits a high α-cellulose content of 96 % and degree of polymerization of 1350. Under optimum synthesis conditions previously identified for unconventional feedstocks, a cellulose nitrate sample was synthesized by treating the pulp with commercially available mixed acid and had the following functional characteristics: 11.26 % nitrogen content, 52 mPа∙s viscosity, and – 95 % solubility on alcohol-ester mixture. Morphological features of pulp and cellulose nitrate samples were characterized by scanning electron microscopy. IR spectroscopy revealed the presence of functional groups in pulp samples (3411, 2913, 1637, 1429, 1369, 1317, 1161, 700-500 cm-1) and cellulose nitrate samples (2553, 1642, 1276, 830, 746, 680 cm-1), which allow those samples to be identified as cellulose and nitrate cellulose esters, respectively. It was found by scanning electron microscopy that the cellulose nitrate sample matches industrial Colloxylines by the onset temperature of decomposition (199 °С) and specific head of decomposition (8,43 kJ/g). The practical importance of this study is that we experimentally justify the feasibility to utilize the new, unconventional, domestic, easily renewable feedstock, Miscanthus var. KAMIS, as a precursor of high-quality cellulose nitrates
Kenevir, Cannabaceae familyasında yer alan, tek yıllık, otsu ve çok yönlü kullanım potansiyeli olan bir endüstri bitkidir. Tarihin en eski bitkilerinden biri olan kenevir, ilaç, gıda, kâğıt, biyoyakıt, tekstil, kozmetik, inşaat ve otomotiv sektörüne kadar oldukça geniş yelpazede kullanım alanına sahiptir. Ekolojik ve topografı istekleri bakımından kanaatkâr bir bitki olan kenevirin adaptasyon kabiliyeti geniştir. Kenevir tohumu yaklaşık %35 yağ ve %25 protein içermesinin yanında Omega-3 kaynağı olarak da zengindir. Endüstriyel kenevir, kaliteli lif kaynağı özelliği sayesinde yakın zamanda geniş ekim alanlarında yer bularak endüstriye önemli ölçüde katkı sağlayacak potansiyele ulaşmıştır. Narkotik özelliklerinden dolayı birçok ülkede olduğu gibi ülkemizde de yasaklanan geleneksel kenevirin aksine son yıllarda geliştirilen endüstriyel amaçlı kenevir çeşitleri sayesinde kenevir tarımı birçok ülkede her geçen gün genişlemekte ve ülkelerin ekonomilerine önemli katkı sağlama potansiyeli arz etmektedir.
Cationic dyes exhibit high exhaustion towards protein fibres, such as wool and silk, due to ionic interactions but they show little substantivity onto cellulosic and hemicellulosic fibres. In order to apply cationic dyes to mill scoured and bleached linen fibers, a new approach employing anionic agents containing a reactive monochloro-S- triazinyl group is synthesized and used to import a negative charge to the fibre surface. Two cationic dyes show considerable substantivity towards anionic agent modified fabrics. Four different anionic agents are covalently bounded to the linen substrate to provide an electrostatic interaction with cationic dyes. The anionic agent treated fabrics are monitoredfor nitrogen content, and the reaction efficiency is determined as a K/S value of the dyed samples. Different factors that affect the pretreatment and dyeing process are investigated, and an overall improvement in the effectiveness of the anionic agent on the dyeability using cationic dyes is achieved. The reaction efficiency for the four anionic agents follows the order: anionic agent III > I > II > IV > untreated fabric. The treated dyed fabrics also exhibit good fastness properties.
Research on the synthesis of in-demand industrial-grade cellulose nitrates from unconventional feedstocks such as Miscan-thus, oat hulls, intermediate flax straw is of the most immediate interest due to a lack of national cotton and to encountered problems with wood cellulose. The celluloses derived herein from the said unconventional feedstocks are inhomogeneous in nature, are com-posed mostly of short fibers, and have non-cellulosic constituents as opposed to elite cotton – these all pose certain difficulties in developing such a nitrocellulose production technology. Besides, it is worth noting that cellulosic fibers of the said feedstocks are peculiar in nature on their own. The findings obtained herein suggest that the research problem can successfully be solved. The pulp samples obtained in this study from the unconventional biomasses by the nitric-acid process have 85−95% α-cellulose and 580−1420 degree of polymerization. These specimens similar in properties to industrial Colloxylin were obtained under optimal synthetic conditions for highly soluble cellulose nitrates by using commercial mixed acid: 11.97–12.29% N, 8–15 mPa∙s, and 98% solubility in alcohol–ester mixture. The morphological features of the resultant cellulose nitrates were characterized by scanning electron microscopy. Infrared spectroscopy revealed the intrinsic frequencies (2560–2550, 1670–1660, 1650–1620, 1280–1270, 830–810, 750–740, 680–670 cm-1) that identify the resultant products as cellulose nitroesters. The practical importance of this re-search is that the nitrocelluloses obtained from the unconventional non-woody feedstocks can be used as the promising component in the manufacture of explosive formulations.
The paper presents the results of the study of the activity of the main
enzymes of phenolic metabolism – peroxidase (POD) and polyphenol
oxidase (PPO) – under the formation of normal wood in silver birch (Betula
pendula Roth var. pendula) and abnormal, figured wood structure in the
Karelian birch (B. pendula Roth var. carelica (Mercl.) Hämet-Ahti).
Karelian birch plants at early ontogenesis stages had no visible signs
of abnormal xylogenesis, but there was a restructuring into a secondary
metabolism, which was accompanied by an increase in the activity of POD
and PPO and a decrease in growth processes., The activity of POD and
PPO correlated linearly with the increase in the degree of wood figure in
adult plants with structural anomalies. The revealed regularities can be the
basis for qualitative and quantitative diagnostics of abnormal xylogenesis.
Hemp plant exhibits various eco-friendly properties and hemp fiber processing does not cause environmental damage, however, it is known that most chemical operations have a risk to interrupt a sustainable production. As stated in several studies, peracetic acid is an important environmental friendly bleaching agent when compared to its conventional competitors. In this study, hemp fabric was bleached with peracetic acid with exhaustion and padding methods. The effects of temperature, pH, process time, concentration on whiteness values were determined. The influences of bleaching processes were investigated via instrumental and imaging methods. Physical properties of the treated fibers were also tested. Besides peracetic acid, hydrogen peroxide bleaching was carried out for comparison. COD values of bleaching effluents were analyzed for selected samples. Higher whiteness values were obtained with exhaustion bleachings than pad-batch bleachings. Quite high whiteness values (up to 68.13 Stensby whiteness index) attained in peracetic acid without significant fiber damage.
Recently the awareness of the demand on eco-friendly dyes in textile applications is increased, since the natural dyes can reveal better biodegradability and generally have a higher compatibility with the environment. This study was conduct on the natural dyes of Crocus Sativus (saffron), growing in Dumre (Elbasan Region). As a natural dye, saffron petals are used in this study for dying cellulosic (cotton) and proteinic (wool) yarns. A series of dyeing were done with the dye extracted from these petals, using two different concentrations of the dye and two types of mordants. Also different method of mordanting like pre, meta or post mordant method are used. The mordant effect on hue, light, wash fastness and perspiration of dyed cotton and wool yarns was investigate as key properties for technical and commercial success. A wide range of shades were obtained because of varying mordant and combinations, from light yellow to light brown. To determinate the amount of the color absorbed by fibres was measured absorbance and transmittance from the solutions taken from each dyeing process. The color fastness properties of the saffron dyed samples are analysed and evaluated based on standard methods, where the washing and perspiration fastness of the dyed samples were assessed giving fair to excellent fastness grades. The results taken give us information on which process of dying and mordant used provides good color fastness. These are helpful information for the use of saffron flowers as a natural dye in textile industry.
Use of natural dyes has increased several folds in the past few years due to the eco-friendly approach of the people. In this paper we present the experimental results of a dyeing process of cotton fabrics with natural colouring matter extracted from Crocus Sativus (saffron). The natural dye was extracted by aqueous method at boiling conditions. Two mordants Fe2(SO4)3 and Al2(SO4)3 were used in pre-mordanting, post-mordanting and simultaneous-mordanting methods.
Cotton fabrics were dyed with colouring solutions of 2.5% and 5%, first without mordant and then with mordant. The color of cotton fabrics dyed without mordant and with mordant was estimated and was observed that the intensity of color varies. It was pointed out, that the best colouring of the sample was in simultaneous-mordanting process. To see the amount of colouring solution that has been absorbed by sample, absorbance was measured for extracts obtained from dyeing process in each case and was observed that the simultaneous-mordanting process gives the best results compared to other processes. Also it was found that Fe2(SO4)3 was the best mordant for cotton fabrics in case of dyestuff 2.5% and Al2(SO4)3 was for dyestuff 5%.
Cannabis sativa is a multi-use crop valued for its pharmacological properties and as a fibre and seed crop. Biotechnological applications toward Cannabis research and product development are still in their early stages. An important feature of biotechnology is the collection of gene transfer technologies that are used to introduce genetic material into host organisms. Agrobacterium tumefaciens and A. rhizogenes represent the most common vectors to transfer genetic material into plant cells. Stable and transient gene expression can be achieved using A. tumefaciens while A. rhizogenes generates stable transformed hairy roots. Cannabis is amenable to genetic transformation using both Agrobacterium vectors, however the plant is recalcitrant to regeneration, impeding the recovery of transgenic Cannabis plants. Despite this shortcoming, the cannabinoid pathway is currently attracting considerable attention from the biotechnology community. Gene transfer technologies have assisted with the characterization of the cannabinoid pathway leading to the synthesis of THCA, the psychoactive compound that is highly valued as a therapeutic. Elucidation of the cannabinoid pathway has led to its metabolic engineering in heterologous hosts. The yeast Pichia pastoris has proven to be a particularly suitable host for the production of cannabinoids. Recently, biotechnology companies have emerged that anticipate commercializing cannabinoid-based drugs in yeast and tobacco and to produce hemp cultivars with the cannabinoid pathway down-regulated or completely knocked out.
Industrial biotechnology has the potential to fulfil many key criteria of greener textile production. This review outlines the current research and future directions on the emerging applications of enzymatic technology in the sustainable production and processing of textiles. The state-of-the-art industrial enzymes in textile processing include amylases for desizing of cotton and cellulases for denim-washing and biopolishing. Aside from these established processes, emerging enzymatic processes such as cotton scouring and bleaching, bast fiber retting/degumming, wool scouring and shrink-proofing, silk degumming, bio-dye production and enzyme-assisted dyeing and finishing are at various stages of development. To illustrate the state of the art, representative examples of enzymes in the processing of various types of textile substrates are discussed and evaluated in this article. The major limitations of the large scale implications of textile biotechnology are lack of sufficient research efforts to make it economically viable option and issues related to the technological glitches. The limitations of existing approaches will be highlighted and the requirement of continuous improvement to overcome current obstacles will be demonstrated by critical assessment.
New technologies are emerging nowadays in industrial practices and the textile industry could not be omitted from this technical progress. From this industry, technical textiles are designed to satisfy particular needs in different fields of activity. Among these, one of the most important and rapidly expanding sectors is that of medical textiles. The use of textiles in medicine has a long tradition. Because there are a huge number of diverse applications of medical textiles, in this chapter only the new trends in this field will be attained. First of all, the attention will be focused on biopolymers as alginate, collagen, chitin, chitosan, cellulose and bacterial cellulose, gelatine and others which have already their place in advanced biomedical applications. The use of fibers and textiles in medicine has increased exponentially as new types of fibers, new innovative structures and new therapies have been developed. Secondly, the progress accomplished in the new emerging technologies like nanotechnology, electrospinning and biotechnology will be underlined. There will be also presented the progress achieved in the advanced materials for regenerative medicine, wound healing and drug delivery. The development of wound dressing has changed from passive to actives types, having some specific functions in order to enhance wound healing without trauma for the patient. Textile structures for wound dressing can contain specialized additives with various properties, such as antibacterial properties. Among these, silver in different forms is the most well known, being used in medical applications. The future will select the best of the solutions proposed in our days, but it is sure that the era of smart textiles or even intelligent textiles has already begun.
Flax are amongst the oldest fiber crops and oil crops in the world. The use of flax for the production of linen can be traced back 5000 years. This article excerpts the latest research results and current scientific advances in several areas. The literature is edited from three aspects: (1) model, (2) mechanical properties, (3) yarn quality.
In this chapter, the various types of plant fibres used in fabrication of paper, cardboard and textiles are defined and the link between genes, the structure of plant cell walls, and fibre quality is explained. Examples of how biotechnological engineering has been used to modify fibre properties in cotton and flax are given. Recent advances in genomics, proteomics and metabolomics are discussed in terms of how they are contributing to a greater understanding of fibre formation and development, thereby paving the way for more sophisticated genetic engineering in different plant species.
Fibres in the middle part of the hypocotyl of young flax plantlets are organised in a circle of one hundred cells around the vascular cylinder. Apart from cellulose, their walls, of large thickness (2-5 μm), contain 30 to 50% of non-cellulosic polysaccharides (NCPs). NCPs consist mainly of β-(1-4)-galactan, together with rhamnogalacturonan of type I and polygalacturonic acid. Transmission electronic microscopy, coupled with immunocytochemical labellings shows that arabinogalactan proteins are also present and may contribute to the galactose and arabinose contents of cell walls. Mannose is one of the sugars tightly bound to cellulose residue, indicating that mannoseenriched polymers are good candidates to cross-link pectins with cellulose microfibrils.
Flax (Linum usitatissimum L.) has been grown for more than 6000 years, primarily for oil and fiber. Advances in plant biotechnology have resulted in flax cultivars with increased herbicides resistance and there is potential to produce transgenic flax with seed oil containing fatty acids with nutraceutical properties. Flax oil is a rich source of alpha-linolenic acid (ALA, 18:3(cis Delta 9,12,15)), a precursor of the very long chain polyunsaturated fatty acids (VLCPUFA), eicosapentaenoic acid EPA, 20:5(cis Delta 5,8,11,14,17)), and docosahexaenoic acid (DHA, 22:6(cis Delta 4,7,10,13,16,19)). Current research on medicinal applications of omega-3 fatty acids, especially to reduce the risk of cardiovascular diseases and cancer, suggests that genetic modification of flax may provide substantial health benefits. There are concerns, however, with the commercialization of genetically engineered (GE) flax (which includes the potential movement of transgenes by pollen and seed, and subsequent introgression with weedy and wild relatives, impact on non-target organisms, and changes in biodiversity). A prerequisite to the unconfined cultivation of transgenic flax is an environmental risk assessment analysis. In this paper, we discuss the history and current status of genetic transformations in flax, potential benefits and consequences of GE flax, and the government regulatory framework in Canada for regulating novel flax. Finally, we discuss the best management practices to mitigate transgene movement from transgenic flax. Our intent was to evaluate biology and agronomy to predict the environmental biosafety of GE flax before commercial cultivation.
Flax has attracted human attention since at least the New Stone Age (the Neolithic), as one of a few crops from which highly valued products can be extracted from both seeds and straw. In addition to its continued production for linen textiles, flax fiber is finding new uses in industrial materials, which, along with reported health benefits of flax seed consumption, have created new interest in the biology of bast fiber development in this species. Bast fibers are long and scientifically intriguing cells that undergo intrusive growth and a special process of secondary cell wall assembly. Biochemical and genetic studies are revealing new information about the development of bast fibers, and providing a foundation for further manipulation of these unusual cells through biotechnology.
The mechanisms underlying bast fibre differentiation in hemp ( Cannabis sativa L.) are largely unknown. We hybridised a cDNA microarray with RNA from fibre enriched tissues extracted at three different positions along the stem axis. Accordingly, we identified transcripts that were enriched in tissues in which phloem fibres were elongating or undergoing secondary wall thickening. These results were consistent with a dynamic pattern of cell wall deposition involving tissue specific expression of a large set of distinct glycosyltransferases and glycosylhydrolases apparently acting on polymers containing galactans, mannans, xylans, and glucans, as well as raffinose-series disaccharides. Putative arabinogalactan proteins and lipid transfer proteins were among the most highly enriched transcripts in various stem segments, with different complements of each expressed at each stage of development. We also detected stage-specific expression of brassinosteroid-related transcripts, various transporters, polyamine and phenylpropanoid related genes, and seven putative transcription factors. Finally, we observed enrichment of many transcripts with unknown biochemical function, some of which had been previously implicated in fibre development in poplar or cotton. Together these data complement and extend existing biochemical models of bast fibre development and secondary wall deposition and highlight uncharacterised, but conserved, components of these processes.
In spite of much effort, no one has succeeded in isolating and characterizing the enzyme(s) responsible for synthesis of cellulose, the major cell wall polymer of plants. We have characterized two cotton (Gossypium hirsutum) cDNA clones and identified one rice (Oryza sativa) cDNA that are homologs of the bacterial celA genes that encode the catalytic subunit of cellulose synthase. Three regions in the deduced amino acid sequences of the plant celA gene products are conserved with respect to the proteins encoded by bacterial celA genes. Within these conserved regions, there are four highly conserved subdomains previously suggested to be critical for catalysis and/or binding of the substrate UDP-glucose (UDP-Glc). An overexpressed DNA segment of the cotton celA1 gene encodes a polypeptide fragment that spans these domains and binds UDP-Glc, while a similar fragment having one of these domains deleted does not. The plant celA genes show little homology at the N- and C-terminal regions and also contain two internal insertions of sequence, one conserved and one hypervariable, that are not found in the bacterial gene sequences. Cotton celA1 and celA2 genes are expressed at high levels during active secondary wall cellulose synthesis in developing cotton fibers. Genomic Southern blot analyses in cotton demonstrate that celA forms a small gene family.
Cellulose, an abundant, crystalline polysaccharide, is central to plant morphogenesis and to many industries. Chemical and ultrastructural analyses together with map-based cloning indicate that the RSW1 locus of Arabidopsis encodes the catalytic subunit of cellulose synthase. The cloned gene complements the rsw1 mutant whose temperature-sensitive allele is changed in one amino acid. The mutant allele causes a specific reduction in cellulose synthesis, accumulation of noncrystalline beta-1,4-glucan, disassembly of cellulose synthase, and widespread morphological abnormalities. Microfibril crystallization may require proper assembly of the RSW1 gene product into synthase complexes whereas glucan biosynthesis per se does not.
Flax fibres (Linum usitatissimum L.) were subjected to chemical and enzymatic analysis in order to determine the compositional changes brought about by the retting process and also to determine the accessibility of the fibre polymers to enzymatic treatment. Chemical analysis involved subjecting both retted and non retted fibres to a series of sequential chemical extractions with 1% ammonium oxalate, 0.05 M KOH, 1 M KOH and 4 M KOH. Retting was shown to cause minimal weight loss from the fibres but caused significant changes to the pectic polymers present. Retted fibres were shown to have significantly lower amounts of rhamnogalacturonan as well as arabinan and xylan. In addition the average molecular mass of the pectic extracts was considerably lowered. Enzyme treatment of the 1 M KOH extracts with two different enzymes demonstrated that the non retted extract contained a relatively high molecular weight xylan not found in the retted extract. Treatment of the 1 M KOH extracts and the fibres with Endoglucanase V from Trichoderma viride demonstrated that while this enzyme solubilised cellulose as well as xylan and xyloglucan oligomers from the extract, it had limited access to these polymers on the fibre. MALDI-TOF MS analysis of the material solubilised from the extract suggested that the xylan was randomly substituted with 4-O-methyl glucuronic acid moieties. The xyloglucan was shown to be of the XXXG type and was substituted with galactose and fucose units. The enzyme treatments of the fibres demonstrated that the xylan and xyloglucan polymers in the fibres were not accessible to the enzyme but that material which was entrapped by the cellulose could be released by the hydrolysis of this cellulose.
Loblolly pine (Pinus taeda L.) is the most widely planted tree species in the USA and an important tree in commercial forestry world-wide. The large genome size and long generation time of this species present obstacles to both breeding and molecular genetic analysis. Gene discovery by partial DNA sequence determination of cDNA clones is an effective means of building a knowledge base for molecular investigations of mechanisms governing aspects of pine growth and development, including the commercially relevant properties of secondary cell walls in wood. Microarray experiments utilizing pine cDNA clones can be used to gain additional information about the potential roles of expressed genes in wood formation. Different methods have been used to analyze data from first-generation pine microarrays, with differing degrees of success. Disparities in predictions of differential gene expression between cDNA sequencing experiments and microarray experiments arise from differences in the nature of the respective analyses, but both approaches provide lists of candidate genes which should be further investigated for potential roles in cell wall formation in differentiating pine secondary xylem. Some of these genes seem to be specific to pine, while others also occur in model plants such as Arabidopsis, where they could be more efficiently investigated.
The plant cell wall is a highly organized composite that may contain many different polysaccharides, proteins, and aromatic substances. These complex matrices define the features of individual cells within the plant body. Ultimately, the plant wall functions as the determinant of plant morphology. The importance of the plant cell wall is revealed in the shear number of genes that are likely to be involved in cell wall biogenesis, assembly, and modification. For example, over 17% of the 25498 Arabidopsis genes have signal peptides, and over 400 proteins have been identified that reside in the wall (Arabidopsis Genome Initiative, 2000). If just one-half of the proteins with signal peptides function in the biosynthesis, assembly, and modification of the walls, then well over 2000 genes are likely to participate in wall biogenesis during plant development. This number is considerably larger if all the cytosolic proteins that function in substrate generation are included. Beyond this, some integral membrane-associated proteins, such as cellulose synthase, obviously function in cell wall bio genesis but do not contain signal peptides. Thus, it is likely that some 15% of the Arabidopsis genome is dedicated to cell wall biogenesis and modification. Of these, only small subsets have been characterized.
The large vascular meristem of poplar trees with its highly organized secondary xylem enables the boundaries between different developmental zones to be easily distinguished. This property of wood-forming tissues allowed us to determine a unique tissue-specific transcript profile for a well defined developmental gradient. RNA was prepared from different developmental stages of xylogenesis for DNA microarray analysis by using a hybrid aspen unigene set consisting of 2,995 expressed sequence tags. The analysis revealed that the genes encoding lignin and cellulose biosynthetic enzymes, as well as a number of transcription factors and other potential regulators of xylogenesis, are under strict developmental stage-specific transcriptional regulation.
Flax (Linum usitatissimum L.) fibers originate from procambial cells of the protophloem and develop in cortical bundles that encircle the vascular cylinder. We determined the polysaccharide composition of the cell walls from various organs of the developing flax plant, from fiber-rich strips peeled from the stem, and from the xylem. Ammonium oxalate-soluble polysaccharides from all tissues contained 5-linked arabinans with low degrees of branching, rhamnogalacturonans, and polygalacturonic acid. The fiber-rich peels contained, in addition, substantial amounts of a buffer-soluble, 4-linked galactan branched at the 0-2 and 0-3 positions with nonreducing terminal-galactosyl units. The cross-linking glycans from all tissues were (fucogalacto)xyloglucan, typical of type-I cell walls, xylans containing (1->)-[beta]-D-xylosyl units branched exclusively at the xylosyl O-2 with t-(4-O-methyl)-glucosyluronic acid units, and (galacto)glucomannans. Tissues containing predominantly primary cell wall contained a larger proportion of xyloglucan. The xylem cells were composed of about 60% 4-xylans, 32% cellulose, and small amounts of pectin and the other cross-linking polysaccharides. The noncellulosic polysaccharides of flax exhibit an uncommonly low degree of branching compared to similar polysaccharides from other flowering plants. Although the relative abundance of the various noncellulosic polysaccharides varies widely among the different cell types, the linkage structure and degree of branching of several of the noncellulosic polysaccharides are invariant.
Using tobacco transgenic lines altered in the monolignol biosynthetic pathway and which differ in their lignin profiles we have evaluated lignin deposition at the cellular and subcellular levels using several microanalytical techniques. Surprisingly, whereas a Cinnamoyl CoA reductase (CCR) down-regulated line with a strong decrease in lignin content exhibited an overall reduction in lignin deposition in the walls of the different xylem cell types, this reduction was selectively targeted to the fibers in a double transformant (down-regulated for both CCR and Cinnamyl alcohol dehydrogenase (CAD)) displaying a similar degree of global lignin content decrease. Fiber and vessel secondary walls of the transgenic tobacco line homozygous for the ccr antisense gene (CCR.H) down-regulated plants were dramatically destructured, particularly in the S2 sublayer, whereas the deposition of lignins in the S1 sublayer was not significantly modified. In contrast, cell wall organization was slightly altered in xylem cells of the double transformant. The relative distribution of non-condensed and condensed units in lignin, evaluated microscopically with specific antibodies, was differentially affected in the transgenics studied and, in a general way, a drop in non-condensed lignin units (β− 0–4 interunit linkages) was associated with a loss of cohesion and extensive disorganization of the secondary wall. These results demonstrate that lignification is tightly and independently regulated in individual cell types and cell wall sublayers. They also show that down-regulation of specific genes may induce targeted changes in lignin structure and in spatial deposition patterns of the polymer.
As a result of the high cost of farm operations in Europe, there is a considerable demand for agricultural products which have a high added value. One of these potential products is linen fibre for use in both fabrics in which fine but long fibres with high moisture resorption are preferred, and in composites to produce engineered materials, for which high purity and a high Young's modulus is preferred. The production of linen from flax by traditional methods involves retting, a biochemical process which serves to remove pectins and nonstructural carbohydrates. This process, carried out in the field or in the factory, is not very easy to control and the products are of variable quality. Steam explosion treatment (STEX) of flax following dew retting can be controlled to give a well defined severity of treatment (in the range log102.9–log104.1) which leads to good fibre quality with minimum loss in fibre yield. Due to limitations on the rate of steam penetration into the fibre bundles, a minimum treatment of 2 min seems to be necessary. Through the use of NaOH pretreatments and STEX the effect of low degrees of fibre retting can be compensated for and a high yield of useful fibre obtained. The high potential of steam exploded short staple flax fibres for use in textile and technical composites has been demonstrated.
DNA microarray technology is a new and powerful technology that will substantially increase the speed of molecular biological research. This paper gives a survey of DNA microarray technology and its use in gene expression studies. The technical aspects and their potential improvements are discussed. These comprise array manufacturing and design, array hybridisation, scanning, and data handling. Furthermore, it is discussed how DNA microarrays can be applied in the working fields of: safety, functionality and health of food and gene discovery and pathway engineering in plants.
The Arabidopsis thaliana sam1 gene encoding S-adenosylmethionine synthetase (EC 2.5.1.6) was transferred to flax (Linum usitatissimum) cells via Agrobacterium tumefaciens. This enzyme catalyses the conversion of methionine to S-adenosylmethionine (SAM), the major methyl group donor in living cells. The aim of this work was to study the consequences of an increased SAM-synthetase (SAM-S) activity in transgenic cell lines on both the production of mono- and dimethoxylated lignin monomers and the degree of methylesterification of pectins. Hypocotyls were cocultivated with Agrobacterium tumefaciens strain GV3101 (pGV2260) harbouring the pO35SSAM binary vector carrying the sam1 gene under the control of the 35S promoter and the nptII gene for selection of putative transformed cells. Most of the transgenic cell lines exhibited a significant (up to 3.2-fold) increase in SAM-S activity compared to the controls. The results showed that for the cell lines analysed this transformation had no effect on caffeic acid O-methyltransferase (COMT, EC 2.1.1.68) in vitro activity, degree of methoxylation of lignin precursors or lignin deposition, pectin methyltransferase (PMT, EC 2.1.1) in vitro activity, but led to an increase of pectin methylesterification in friable and fast-growing transgenic cell lines.
It has not been possible to isolate a number of crucial enzymes involved in plant cell wall synthesis. Recent progress in identifying some of these steps has been overcome by the isolation of mutants defective in various aspects of cell wall synthesis and the use of these mutants to identify the corresponding genes. Secondary cell walls offer numerous advantages for genetic analysis of plant cell walls. It is possible to recover very severe mutants since the plants remain viable. In addition, although variation in secondary cell wall composition occurs between different species and between different cell types, the composition of the walls is relatively simple compared to primary cell walls. Despite these advantages, relatively few secondary cell wall mutations have been described to date. The only secondary cell wall mutations characterised to date, in which the basis of the abnormality is known, have defects in either the control of secondary cell wall deposition or secondary cell wall cellulose or lignin biosynthesis. These mutants have, however, provided essential information on secondary cell wall biosynthesis.
While there is an ever-increasing amount of information regarding cellulose synthase catalytic subunits (CesA) and their role in the formation of the cell wall, the remainder of the enzymes that synthesize structural cell wall polysaccharides are unknown. The completion of the Arabidopsis genome and the wealth of the sequence information from other plant genome projects provide a rich resource for determining the identity of these enzymes. Arabidopsis contains six families of genes related to cellulose synthase, the cellulose synthase-like (Csl) genes. Our laboratory is taking a multidisciplinary approach to determine the function of the Csl genes, incorporating genomic, genetic and biochemical data. Information from expressed sequence tag (EST) projects has revealed the presence of Csl genes in all plant species with a significant number of ESTs. Certain Csl families appear to be missing from some species. For example, no examples of CslG ESTs have been found in rice or maize. Microarray data and reporter constructs are being used to determine the expression pattern of the CesA and Csl genes in Arabidopsis. Mutations and insertion events have been identified in a majority of the genes in the Arabidopsis
CesA superfamily and are being characterized by phenotypic and biochemical analysis. While we cannot yet link the function of any of the Csl genes to their respective products, the expression and localization of these genes is consistent with the expected expression pattern of polysaccharide synthases that contribute to the primary cell wall.
Cellulose synthesis in plants requires beta-1,4-glucan chain initiation, elongation, and termination. The process of chain elongation is likely to be distinct from the process of chain initiation. We demonstrate that a CesA glucosyltransferase initiates glucan polymerization by using sitosterol-beta-glucoside (SG) as primer. Cotton fiber membranes synthesize sitosterol-cellodextrins (SCDs) from SG and uridine 5'-diphosphate-glucose (UDP-Glc) under conditions that also favor cellulose synthesis. The cellulase encoded by the Korrigan (Kor) gene, required for cellulose synthesis in plants, may function to cleave SG from the growing polymer chain.
Analyses of retted and
- C Mooney
Mooney, C. et al. (2001) Analyses of retted and