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Isolation of Nematicidal Compounds from Tagetes patula L. Yellow Flowers: Structure-Activity Relationship Studies against Cyst Nematode Heterodera zeae Infective Stage Larvae
Abstract
Bioassay-guided isolation studies on the extracts of yellow flowers of Tagetes patula L. against the Heterodera zeae were carried out to identify phytochemicals lethal to this economically important cyst nematode. In vitro investigation of a polar extract and fractions showing activity led to the isolation of phenolic compounds (flavonoids and phenolic acids). In the nonpolar extract, a few fatty acids, their methyl esters, and thiophenes (including α-terthienyl) were detected. In studies of compounds obtained commercially, α-terthienyl and gallic and linoleic acids showed 100% mortality at concentrations of 0.125% after 24 h. Assessment of structure-activity relationships revealed that an increase in the number of hydroxyl groups in phenolic acids increased the activity; with fatty acids, activity depended on chain length and the number and position of double bonds. Crude extracts of the flowers of different colors also have promising activity.
... However, the control effect is not satisfactory because of its instability [12]. Therefore, the development of high-efficiency and low-risk nematicides is still the key scientific problem of nematode control [13][14][15]. ...
... In addition, the mode of action results demonstrated that compound A1 affected the acetylcholine receptor of B. xylophilus. Therefore, the development of high-efficiency and low-risk nematicides is still the key scientific problem of nematode control [13][14][15]. ...
... Then, the target compounds A1-A29 and B1-B19 were obtained with intermediates 1 and acyl chloride or acyl bromide. The structures of all compounds were identified by 1 H NMR, 13 C NMR, and HRMS. The physical properties and spectrogram data of these derivatives are provided in Supporting Information File S1. Figure 2. Design of the target compounds. ...
Plant-parasitic nematodes pose a serious threat to crops and cause substantial financial losses due to control difficulties. Tioxazafen (3-phenyl-5-thiophen-2-yl-1,2,4-oxadiazole) is a novel broad-spectrum nematicide developed by the Monsanto Company, which shows good prevention effects on many kinds of nematodes. To discover compounds with high nematocidal activities, 48 derivatives of 1,2,4-oxadiazole were obtained by introducing haloalkyl at the 5-position of tioxazafen, and their nematocidal activities were systematically evaluated. The bioassays revealed that most of 1,2,4-oxadiazole derivatives showed remarkable nematocidal activities against Bursaphelenchus xylophilus, Aphelenchoides besseyi, and Ditylenchus dipsaci. Notably, compound A1 showed excellent nematocidal activity against B. xylophilus with LC50 values of 2.4 μg/mL, which was superior to that of avermectin (335.5 μg/mL), tioxazafen (>300 μg/mL), and fosthiazate (436.9 μg/mL). The transcriptome and enzyme activity results indicate that the nematocidal activity of compound A1 was mainly related to the compound which affected the acetylcholine receptor of B. xylophilus.
... The nematicidal activity of fatty acids, abundant in our analysis, often depends on chain length and the number and position of double bonds (Faizi et al., 2011). 9-Octadecenoic acid (oleic acid), 9,12-Octadecenoic acid (linoleic acid), and 11-Octadecenoic acid (vaccenic acid) are abundant and naturally occurring fatty acids. ...
... Stadler et al. (1994) reported multiple fatty acids and other compounds isolated from cultures of Basidiomycetes with nematicidal activity against Caenorhabditis elegans. The compounds were similarly identified in our soil samples and their respective reported LD 50 (µg/mL) in the literature are: tetradecanoic acid (5); hexadecanoic acid (25), octadecanoic acid (50), icosanoic acid (100), 9Z)-hexadec-9-enoic acid (10), 9-Octadecenoic acid (25), 9,12-Octadecadienoic acid (5), 9-Octadecenoic acid, and 9,12-Octadecadienoic, octadecanoic, hexadecanoic, and tetradecanoic acids, which significantly controlled Heterodera zeae (corn cyst nematode) under in-vitro conditions (Faizi et al., 2011;Zhang et al., 2012). 9,12-Octadecadienoic acid was shown to be responsible for the nematicidal activity of the Oken fruit (Holigarna caustica Dennst.) ...
We previously reported soybean fields double-cropped with winter wheat having reduced soybean cyst nematode (SCN) ( Heterodera glycines ) counts compared to fallow. A follow-up metagenomics study identified several fungal and bacterial taxa enriched in wheat fields, and some were reported to parasitize SCN. Knowing that phytocompounds with potential nematicidal activity are released via wheat roots and stubble, we implemented a dichloromethane-based extraction method and a gas chromatography-mass spectrometry (GCMS) system to investigate soil chemical profiles of samples collected from these fields and review the potential nematicidal activity of compounds with higher concentration in double cropping fields. 51 compounds were detected during the GCMS analysis, eight with unknown identification. Several compounds, including multiple fatty acids, had larger relative peak areas when double-cropped, compared to fallow samples. This study, along with our previously published one, provided a better understanding of the mechanisms that govern the effect of wheat on SCN populations. Rather than driven by a single mechanism, the suppression of SCN in soybean fields double-cropped with winter wheat was potentially linked to enriched microbial communities, increased populations of beneficial organisms, and higher concentrations of chemicals with potential nematicidal activity. To our knowledge, this is the first study using GCMS to characterize soil chemical profiles in soybean fields double-cropped with winter wheat regarding the suppression of SCN populations.
... Research concerning S. elaeagnifolium to date has mainly focused on its invasion pattern [38,40], morphological variation, evolution, and genetic differentiation as factors contributing to its adaptability and invasive potential [41][42][43], competitive ability against crops [44][45][46] and ability to interfere with ecosystem services such as pollination [47,48] and crop production as a host of plant pathogens and pests [49,50]. Studies on the chemical nature of S. elaeagnifolium have revealed that its secondary metabolites have an adverse effect against plant parasitic nematodes such as Heterodera zeae Koshy, Swarup and Sethi and Meloidogyne incognita (Kofold & White) Chitwood [51,52] and may reduce the total counts of rhizosphere bacteria and fungi [53]. The only study regarding the effect of S. elaeagnifolium invasion on soil nematodes was conducted recently by Karmezi et al. [54], which found a reduction of nematode diversity and changes in the trophic structure of the soil nematode community during the naturalization process of this alien plant. ...
... Microbial feeders accounted for 94% of the total nematode community at (Pc), while this percentage dropped to 71% at (Ppr) and further to 54% at Pinv. The reduced nematode abundance at Pinv could result from the allelopathic compounds of S. elaeagnifolium, which have exhibited nematicidal effects [51,52,69]. However, Karmezi et al. [54] did not report any suppression of microbivorous soil nematodes in the rhizospheres of S. elaeagnifolium. ...
We aimed to explore how the invasion of the alien plant Solanum elaeagnifolium affects soil microbial and nematode communities in Mediterranean pines (Pinus brutia) and maquis (Quercus coccifera). In each habitat, we studied soil communities from the undisturbed core of both formations and from their disturbed peripheral areas that were either invaded or not by S. elaeagnifolium. Most studied variables were affected by habitat type, while the effect of S. elaeagnifolium was different in each habitat. Compared to maquis, the soil in pines had higher silt content and lower sand content and higher water content and organic content, supporting a much larger microbial biomass (PLFA) and an abundance of microbivorous nematodes. The invasion of S. elaeagnifolium in pines had a negative effect on organic content and microbial biomass, which was reflected in most bacterivorous and fungivorous nematode genera. Herbivores were not affected. In contrast, in maquis, organic content and microbial biomass responded positively to invasion, raising the few genera of enrichment opportunists and the Enrichment Index. Most microbivores were not affected, while herbi-vores, mostly Paratylenchus, increased. The plants colonizing the peripheral areas in maquis probably offered a qualitative food source to microbes and root herbivores, which in pines was not sufficient to affect the much larger microbial biomass.
... The general mechanism of toxicity for these other quinone compounds seems to be the same and involves ROS generation that causes oxidative damage to cells (Chen et al. 2015;Kanvah & Schuster 2006). Interestingly, plants use many non-quinone chemical compounds in defence, such as hydrogen peroxide with peroxidase (Zacheo et al. 1982) and alphaterthienyl (Faizi et al. 2011), which also have toxic effects against nematodes by generating ROS. This supports the need for further investigation into the mechanisms by which EBQ and MBQ reduced S. carpocapsae survival here. ...
Given the threat presented by parasites and pathogens, insects employ various defences to protect themselves against infection, including chemical secretions. The red flour beetle Tribolium castaneum releases a secretion containing the benzoquinones methyl-1,4-benzoquinone (MBQ) and ethyl-1,4-benzoquinone (EBQ) into the environment. These compounds have known antimicrobial effects; however, their role in defence against macroparasites is not known. Entomopathogenic nematodes, such as Steinernema carpocapsae, present a serious threat to insects, with successful infection leading to death. Thus, quinone-containing secretions may also aid in host defence. We tested how exposure to the individual components of this quinone secretion, as well as a mix at naturally-occurring proportions, affected the survival and thrashing behaviour of S. carpocapsae, as well as their virulence to a model host (Galleria mellonella). Exposure to high concentrations of MBQ and EBQ, as well as the quinone mix, significantly increased nematode death but did not consistently reduce thrashing, which would otherwise be expected given their toxicity. Rather, quinones may act as a host cue to S. carpocapsae by triggering increased activity. We found that exposure to quinones for 24 or 72 hours did not reduce nematode virulence, and surviving nematodes remained infective after non-lethal exposure. Our results indicate that quinone secretions likely serve as a defence against multiple infection threats by reducing S. carpocapsae survival, but further research is required to contextualize their roles by testing against other nematodes, as well as other helminths using insects as hosts.
... and oleic acid (85.00±4.0) against the cyst nematode Heterodera zeae [43]. Within a column, mean values (a, b, c, d, e, f) followed by the same letter are not significantly different according to Tukey's and Duncan's test (p < 0.05). ...
The objective of the present study was to examine the chemical compositions of Salvia coccinea oleoresins prepared in methanol and petroleum ether. GC-MS analysis of Salvia coccinea methanolic oleoresin (SCMO) and Salvia coccinea ether oleoresin (SCEO) resulted in the identification of 15 and 12 constituents, comprising 84.7 and 81.2% of the total composition, respectively. Both SCMO and SCEO varied in their chemical composition in terms of quantity, namely, oleic acid (22.3-25.9%), palmitic acid (8.9-8.4%), stigmasta-3,5-dien-7-one (3.4-11.8%), stigmasterol acetate (3.5-5.3%), neophytadiene (4.8-1.7%), phytol (1.6-7.8%) and phthalic acid (2.1-3.1%). In addition to the qualitative differences between SCMO and SCEO concomitantly, both oleoresins were examined for their pesticidal activities. Oleoresins demonstrated significant nematicidal activity against Meloidogyne incognita, insecticidal activity against Lipaphis erysimi, antifungal activity against Curvularia lunata, and antibacterial activity against Staphylococcus aureus. For nematicidal activity, SCMO and SCEO exhibited a high mortality of 65.66±1.69 and 54.33±1.24 and egg hatching inhibition of 26.33±1.20and 33.33±1.24 at 200 μg/mL. Similarly, SCMO and SCEO exhibited excellent insecticidal activity with 94.87±1.44 % and 86.75±1.85 % mortality at 1000 μg/mL. However, both oleoresins exhibited moderate antifungal and antibacterial activities compared to standards. Due to the quantitative difference in chemical composition and the presence of several phytoconstituents that were absent in SCEO, SCMO displayed stronger pesticidal effects than SCEO. To estimate the binding energy and structure-activity relationships between chemical constituents and pesticidal activities, in silico molecular docking and ADME/Tox studies have also been performed using a web-based online tool. On the basis of the present study, it is inferred that the herb Salvia coccinea might be a good source of phytochemicals and can be used for the development of herbal-based pesticides/formulations after proper clinical trials.
... Flavonoids are a large class of secondary metabolites present in plants and have several functions, such as plant development through the control of auxin, antioxidants, chemoattractants, and defense compounds, among others. Studies report that flavonoids can induce quiescence by decreasing the movement of nematodes, modifying their migration towards the root, repelling, and even killing them [70,71]. Flavonoids are also important in response to a water deficit, and their accumulation is often associated with drought resistance [72,73]. ...
The co-occurrence of biotic and abiotic stresses in agricultural areas severely affects crop performance and productivity. Drought is one of the most adverse environmental stresses, and its association with root-knot nematodes further limits the development of several economically important crops, such as cowpea. Plant responses to combined stresses are complex and require novel adaptive mechanisms through the induction of specific biotic and abiotic signaling pathways. Therefore, the present work aimed to identify proteins involved in the resistance of cowpea to nematode and drought stresses individually and combined. We used the genotype CE 31, which is resistant to the root-knot nematode Meloidogyne spp. And tolerant to drought. Three biological replicates of roots and shoots were submitted to protein extraction, and the peptides were evaluated by LC-MS/MS. Shotgun proteomics revealed 2345 proteins, of which 1040 were differentially abundant. Proteins involved in essential biological processes, such as transcriptional regulation, cell signaling, oxidative processes, and photosynthesis, were identified. However, the main defense strategies in cowpea against cross-stress are focused on the regulation of hormonal signaling, the intense production of pathogenesis-related proteins, and the downregulation of photosynthetic activity. These are key processes that can culminate in the adaptation of cowpea challenged by multiple stresses. Furthermore, the candidate proteins identified in this study will strongly contribute to cowpea genetic improvement programs.
The huge diversity of worms belongs to various classes such as Nematoda, Trematoda, and Cestoda, which are responsible for helminth-mediated diseases. Among those, parasitic helminths are significant candidates for many diseases in this context. To cure this type of parasitic helminth-mediated disease, several traditional medicinal plants, which include Ayurvedic and Chinese medicine plants, have already been checked for cytotoxic, anti-parasitic, anti-filarial, anti-helminthic, and anti-leishmanial activity characteristics, and promising drugs could be discovered from plant extract. Here the authors summarize the effects of helminths together along with plant source and their bioactive compounds to treat helminthic-mediated diseases.
The work is aimed to evaluate the blood pressure reducing effect of constituents from methanol extract and associated constituents of Tagetes patula flowers in normotensive and L-NAME induced hypertensive rats. The HPLC analysis of methanol extract of Tagetes patula flowers (JFM) resulted in the quantitative identification and percent comparison of four phenolic constituents, protocatechuic acid (PA), methyl protocatechuate (MPA), patulitrin (TRIN) and patuletin (PAT). All the extracts, fractions and compounds examined showed significant blood pressure lowering activity. Patulitrin (TRIN) which has emerged as the major constituent (15.33%) of T. patula flowers showed significant 30% and 68% fall in blood pressure in normotensive and L-NAME induced hypertensive rats respectively. The patuletin (PAT), which is an aglycone of TRIN displayed high percentage (84%) of antihypertensive activity. Further, comprehensive and advanced studies on these constituents may result in preparation of an effective blood pressure lowering medicine with active precious rare flavonoids, patuletin and patulitrin.
Nematolojik açıdan tuzak bitki uygulamaları, topraktaki nematod populasyonunu baskılamak amacıyla uygulanabilecek bitki temelli stratejilerden biridir. Tuzaklama stratejilerinde, nematod ve konukçusu arasındaki parazitik ilişki kritik bir öneme sahiptir. Bir alanda tuzak bitkilerin kullanım şekli, tuzak bitki olarak kullanılan bitkinin özelliği ve bu bitkinin imha edilme zamanına bağlı olarak değişmekle beraber; genellikle ana ürün ile aynı zamanda tekli sıralar, çoklu sıralar veya düzensiz dağılım şeklinde ya da ana üründen önce yetiştirilme şeklinde olabilir. Her ne kadar, nematodlar için tuzak bitki olarak bilinen bitki sayısı sınırlı olsa da, nematodun konukçusu ile olan beslenme davranışı da dikkate alındığında, hassas bitkilerin bile tuzaklama amacıyla kullanılabilecek potansiyelde olması, bu uygulamanın bir mücadele stratejisi olarak kullanılabilme potansiyelini artırmaktadır. Özellikle, tuzak bitkilerin hassas bitkiler arasında kısa süreli yetiştirilmesiyle, üretim yapılan alandaki nematod populasyonunun etkili bir şekilde azaldığı ve kendinden sonra yetiştirilen bitkide, belirgin verim artışı sağlandığı bilinmektedir. Ayrıca, kimyasal kullanımının da azalmasına katkı sağlayan bu yaklaşımlar, hem ekonomik olarak daha karlı bir üretimin yapılmasını, hem de çevre ve insan sağlığı için güvenli ve sürdürülebilir bir üretimin gerçekleştirilebilmesini sağlamaktadır. Bu nedenle, kök-ur nematodları ile mücadelede tuzak bitkilerin kullanımının ele alındığı çalışmada, öncelikle kök-ur nematodunun biyolojisi hakkında özet bilgi verilerek, nematod biyolojisi ve tuzaklama stratejileri ile bağlantısı açıklanmaya çalışılmıştır. Tuzaklamanın 2 uygulama şekli olan; tuzak özelliğine sahip bitkilerin kullanıldığı uygulamalar ile hassas bitkilerin tuzak olarak kullanıldığı uygulamalar ve tuzaklama uygulamasını destekleyici stratejiler, günümüze değin yapılan örneklerle derlenerek özetlenmiştir.
The current study evaluates the antibacterial and antifungal activities of extracts from different parts of Tagetes patula. Linn. (Asteraceae), reported for the first time in a single set of experiments. In the preliminary assay, the methanol extract of the flower (JFM) was found to possess antimicrobial activity against a number of bacteria with inhibition zone diameters ranging from 9 to 20 mm, the bioassay-guided fractionation of which led to the isolation of a flavonoid patuletin (3) in high yield as the active antibacterial principle with minimum inhibitory concentration (MIC) value of 12.5 μ g/disk against Corynebacterium. spp., Staphylococcus. spp., Streptococcus. spp., and Micrococcus luteus.. Its glucoside, patulitrin (4), was found to be weakly active, except against Staphylococcus saprophyticus., Streptococcus fecalis., and Streptococcus pyogenes. with inhibition zone diameters of 11, 16, and 12 mm, respectively. The cinnamate derivative (3b) of 3 showed antibacterial activity comparable with the parent flavonoid with a MIC value of 50 μ g/disk against Corynebacterium. spp., whereas benzoate derivative (3a) was found to be devoid of any activity; both the derivatives are new compounds. Moreover, the long-chain alcohol 5, which displayed antibacterial activity in the preliminary testing, was obtained in large quantity directly from the petroleum ether extract of the involucre of the flowers.
The dithiophenes and trithiophenes reviewed in this article are part of a large group of biogenetieally related molecules found in plants of the family Compositae (Asteraceae). They include compounds having a variable number of unsaturations, particularly double bonds and triple bonds, which occur singly or in combinations. The first report of a naturally occurring trithiophene, α-terthienyl in the flowers of Tagetes erecta, appeared in 1947 (270); the first naturally occurring dithiophene was isolated from Bidens radiata and described in 1961 (142). The book Naturally Occurring Acetylenes, by BOHLMANN
et al (29), is a superb review of the field up to 1972. Interestingly, out of its more than 500 pages, only two were devoted to physiological and pharmacological aspects. BOHLMANN and ZDERO later contributed one chapter, “Naturally Occurring Thiophenes”, to a volume Thiophenes and its Derivatives which appeared in 1985 (57). This chapter presents a survey of such thiophenes based on biogenetic considerations, includes an extensive analysis of the distribution of these compounds, and discusses methods of analysis based on UV, 1H-NMR, 13C-NMR, and mass spectra. The most recent references in the chapter came from publications appearing in 1981.
Five different plants were evaluated for their nematicidal effect through their aqueous extract (Acacia gummifera, Ceratonia siliqua, Ononis natrix, Tagetes patula and Peganum harmala). The extracts used directly on the nematods (in vitro test) showed a variable nematicidal effect that ranged between 67% and 95%. P. harmala has a similar effect than the commercial nematicidal (Vydate). Phytochemical analysis (screening) revealed that this plant is rich on alkaloids. Also, a high nematicidal effect of 84% and 82% was obtained respectively with A. gummifera and T. patula extracts. The phytochemical screening of these two plants showed a significant content of flavonoids. The extract of O. natrix and C. siliqua had a nematicidal effect against Meloidogyne spp., with 67% and 71% of mortality respectively.
Cyst nematodes represent a large group of plant parasites comprising 75 or more species. These species are presently included in six genera of the family Heteroderidae: Heterodera, Globodera, Cactodeva, Punctodera, Dolichodera, and Afenestrata. In addition, Sarisodera was described and recognised as a cyst genus (Wouts and Sher, 1971) but Baldwin and Bell (1985) recently determined that cysts were not formed by its type species and placed the genus with related non-cyst forms. Whatever their origin, host, or economic status, accurate identification of cyst nematodes is of paramount importance for any decision making process. They may be revealed as a known species, an undescribed taxon, or possibly some species which is still so poorly described as to make identification impossible; but the key to their identity is their morphology.
Marigold (Tagetes patula L.) hairy roots induced by infection with Agrobacterium rhizogenes produced α-terthienyl when grown in darkness, and an n-hexane extract of the roots showed nematocidal activity. Depending on the hairy root line used, the level of α-terthienyl varied from 15 to 1268 μg per g dry weight, a level that corresponded to 0.15 to 12.7-fold that in intact roots. Analysis by HPLC indicated that the nematocidal activity was due predominantly to α-terthienyl. However, it is suggested that nematocidal compounds other than α-terthienyl are present in hairy roots cultured in the dark for long periods or in the light.
A plethora of research has been conducted on the use of marigolds (Tagetes spp.) for nematode suppression, yet limited cover cropping with marigold is being practiced in commercial operations. Marigold is well known among nematologists for its ability to produce compounds such as α-terthienyl that are allelopathic to many species of plant-parasitic nematodes. However, there are contradictory reports on how this compound is released. The uncertainty centers on whether allelopathic compounds are released from root or shoot tissues, by growing live plants or soil-amended tissues, as a response to nematode penetration, or as a non-specific repellent. Other mechanisms by which marigold suppresses plant-parasitic nematodes include acting as a poor host, enhancing nematode-antagonistic microorganisms, or acting as a “dead-end” trap crop. Interpretation is complicated because multiple mechanisms may operate simultaneously. Understanding the exact mechanisms responsible for the nematode-suppressive effects of marigold could lead to further/broader incorporation into nematode management programs. This literature review revealed variable findings from marigold use. For example, in some instances using marigold was reported to be more effective than nematicides or soil fumigants and in other instances it had a negative impact on cash crop growth and yield. This variation has been attributed to differences in the way marigolds were used (e.g. intercrop/cover crop/soil amendment, seeding rate, time between marigold and cash crop), marigold cultivar, species or races of target nematodes, temperature, or age of marigold plant. Thus, future research should focus on determining the exact causes of this variability and on developing field IPM programs that take advantage of the nematode-suppressive potential of marigold.
An inherently unstable and structurally novel tetrahydro β-carboline alkaloid, (+) jafrine (1) was isolated from the petroleum ether extract of Tagetes patula flowers. Its structure and stereochemistry has been determined with the help of spectroscopic analysis and the synthesis of racemate, (±) jafrine starting from available (±) tetrahydroharmine (2). The effect of solvent polarity on the ratio of amide rotamers of jafrine during NMR studies is discussed. The transformation of jafrine as well as 4-N-acetyl tetrahydroharmine (3), into 2-acetyl tryptamine derivatives by auto-oxidation was observed and its detail is presented. This process may be used as a synthetic tool for the preparation of tryptamine derivatives.
An H/D exchange process in patuletin (1) and its derivatives in D-donor solvents (e.g., CF3COOD), which occurs regioselectively at C(8) was observed for the first time during NMR studies. The effect of substituents and temperature on the deuteration of various flavonoids (see Fig. 1) which include apigenin, chrysin, galangin, kaempferol, luteolin, morin, myricetin, patuletin, patulitrin, and quercetin, as well as derivatives of patuletin was examined extensively under NMR conditions. The rate constant of deuteration at C(8) of patuletin (1) and two flavones, luteolin (3) and apigenin (12), was also determined in CF3COOD. The D-atom was introduced into the flavonoids via a keto–enol tautomerism (Scheme 1). During these studies, monodeuterated patuletin was also obtained as a new compound. The examined flavonoids have been reported to possess significant pharmacological activities, and their deuterated derivatives would be of importance for the identification and quantification of these compounds in biological matrices.