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ABSTRACT: Malting is the ideal stage to deal with β-glucans. Their hydrolysis is very important as the diffusion of both hormones and hydrolytic enzymes in the endosperm of germinated grain depend on it. A high malt β-glucanase activity is not a guarantee of an extensive hydrolysis of β-glucans. When Bacillus subtilis is used to control mould growth, red sorghum malt β-glucanase activity (measured using carboxymethylcellulose as the substrate) was improved without significantly affecting the hydrolysis of malt β-glucans. Thus, in order to reduce the residual β-glucans content, soaking in 0.2% NaOH was combined with a biocontrol. Soaking in 0.2% NaOH is recognized as capable of improving grain hydration by opening-up the endosperm cell walls. The combined use of 0.2% NaOH with Bacillus subtilis-based biocontrol treatments during red sorghum malting, leads to malt with increased β-glucanase activity and a significant reduction of residual β-glucans when compared with the 16 h biocontrol steeping without prior steeping in 0.2% NaOH. β-glucanase activity increases with increased germination temperature and time while, conversely, the residual β-glucans content of the malts decreases. Indeed, while the level of β-glucanase was not vastly different between the malts obtained after steeping in distilled water and those obtained after 8 h steeping in 0.2% NaOH followed by 8 h resteeping in distilled water (NaOH+H2O treatment), their residual β-glucans levels differ significantly. Bacillus subtilis-based treatment leads to malt with improved β-(1-3)- and β-(1-4)-glucanase activities without significantly improved malt β-(1-3),(1-4)-glucanase activity. While malts obtained after 84 h germination weren’t significantly different in terms of malt β-(1-3),(1-4)-glucanase activities for all steeping treatments, the use of 0.2% NaOH steeping prior to resteeping led to malts with improved β-glucans content. Combining the steeping in dilute alkaline and biocontrol enables taking advantage of the dilute alkaline effect on residual β-glucans content, due probably to the opening-up the cell walls and the improvement of water uptake, and that of the biocontrol (improvement of β-glucanase synthesis).
Journal of Cereal Science 03/2013; · 2.07 Impact Factor
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ABSTRACT: The extracellular lipase of Yarrowia lipolytica presents numerous potentialities for biotechnological applications. This work describes the development and storage of powders obtained from supernatants containing Y. lipolytica lipase by freeze-drying as downstream process that is important in obtaining a stable lipase powder with high enzymatic activity. Lipase was produced by Y. lipolytica U6 mutant strain in 20-L bioreactor. Non-concentrated cell-free culture supernatant samples were supplemented with different concentrations (0.5-1 %) of maltodextrin and glycerol as additives to freeze-drying. Effects of additives, temperature, pH, and storage time on lipase powders were determined. After addition of additives, freeze-drying yield increased 3.5-fold compared to supernatant without additive. Maltodextrin with 0.5 % concentration gave the best protection of lipase during dehydration treatment and its freeze-drying yield (77 %) is better than other formulations. Lipase powders were stored at 4 and 25 °C for 46 weeks without loss of lipase activity. A common impediment to the production of commercial enzyme is their low-stability aqueous solutions. The present study shows that freeze-dried lipase powders of Y. lipolytica have good stability for storage and various applications.
Applied biochemistry and biotechnology 08/2012; · 1.94 Impact Factor
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Christel Mattéotti,
Julien Bauwens,
Catherine Brasseur,
Cédric Tarayre,
Philippe Thonart, Jacqueline Destain,
Frédéric Francis,
Eric Haubruge,
Edwin De Pauw,
Daniel Portetelle,
Micheline Vandenbol
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ABSTRACT: Termites are world champions at digesting lignocellulosic compounds, thanks to cooperation between their own enzymes and exogenous enzymes from microorganisms. Prokaryotic cells are responsible for a large part of this lignocellulolytic activity. Bacterial enzyme activities have been demonstrated in the higher and the lower termite gut. From five clones of Gram-positive bacteria isolated and identified in a previous work, we constructed a genomic DNA library and performed functional screening for alpha-amylase, beta-glucosidase, and xylanase activities. One candidate, Xyl8B8, showed xylanase activity. Sequence analysis of the genomic insert revealed five complete ORFs on the cloned DNA (5746bp). Among the encoded proteins were a putative endo-1,4-beta-xylanase (XylB8) belonging to glycoside hydrolase family 11 (GH11). On the basis of sequence analyses, genomic DNA organization, and phylogenetic analysis, the insert was shown to come from an actinobacterium. The mature xylanase (mXylB8) was expressed in Escherichia coli and purified by affinity chromatography and detected by zymogram analysis after renaturing. It showed maximal xylanase activity in sodium acetate buffer, pH 5.0 at 55 °C. Its activity was increased by reducing agents and decreased by Cu(2+), some detergents, and chelating agents. Its substrate specificity appeared limited to xylan.
Protein Expression and Purification 04/2012; 83(2):117-27. · 1.59 Impact Factor
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ABSTRACT: Enterococci: advantages and drawbacks in biotechnology, a review. Enterococci are lactic acid bacteria that have been used for centuries in food processing. These microorganisms play a vital role in conservation (extension of shelf life) and in the bacteriological quality of food while keeping their nutritional and organoleptic properties. However, Enterococcus faecium and Enterococcus faecalis are indicators of faecal contamination and are also implicated in nosocomial diseases. The genetic plasticity (transfer of genetic elements) of these bacteria allows them not only to adapt to various ecosystems, but also to be vehicles of antibiotic resistances and bacterial virulence, which is of public health concern. Thus, the use of enterococci in the food industry is becoming controversial. However, enterococci are also involved in the fermentation of many foods (milk, vegetables, meats or fish) and are able to produce various antimicrobial molecules (e.g. lactic acid, bacteriocins or hydrogen peroxide) that make them indispensable in the food industry. Their use as probiotic must therefore be carefully characterized in order to prove their safety. The wide range of bacteriocins (enterocins) found in these bacteria could also be valorized by developing purification methods to replace the bacterial strains themselves by their enterocins in foodstuffs, therefore eliminating the risk of direct use of bacteria.
Biotechnol. Agron. Soc. Environ. 01/2012; 16(1):67-76.
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ABSTRACT: The potentialities for the intensification of the process of lipase production by the yeast Yarrowia lipolytica on a renewable hydrophobic substrate (methyl oleate) have to be investigated. The key factor governing the lipase yield is the intensification of the oxygen transfer rate, considering the fact that Y. lipolytica is a strict aerobe. However, considering the nature of the substrate and the capacity for protein excretion and biosurfactant production of Y. lipolytica, intensification of oxygen transfer rate is accompanied by an excessive formation of foam. Two different foam control strategies have thus been implemented: a classical chemical foam control strategy and a mechanical foam control (MFM) based on the Stirring As Foam Disruption principle. The second strategy allows foam control without any modifications of the physico-chemical properties of the broth. However, the MFM system design induced the formation of a persistent foam layer in the bioreactor. This phenomenon has led to the segregation of microbial cells between the foam phase and the liquid phase in the case of the bioreactors operated with MFM control, and induced a reduction at the level of the lipase yield. More interestingly, flow cytometry experiments have shown that the residence time of microbial cells in the foam phase tends to induce a dimorphic transition which could potentially explain the reduction of lipase excretion.
Bioprocess and Biosystems Engineering 09/2011; 35(4):483-92. · 1.81 Impact Factor
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ABSTRACT: An intracellular symbiotic bacterium was isolated from the flora of a natural clone of the black bean aphid Aphis fabae. The strain was able to grow freely in aerobic conditions on a rich medium containing 1 % of each of the following substrates: glucose, yeast extract and casein peptone. Pure culture was achieved through the use of solid-phase culture on the same medium and the strain was designated CWBI-2.3(T). 16S rRNA gene sequence analysis revealed that strain CWBI-2.3(T) was a member of the class Gammaproteobacteria, having high sequence similarity (>99 %) with 'Candidatus Serratia symbiotica', the R-type of secondary endosymbiont that is found in several aphid species. As strain CWBI-2.3(T) ( = LMG 25624(T) = DSM 23270(T)) was the first R-type symbiont to be isolated and characterized, it was designated as the type strain of Serratia symbiotica sp. nov.
INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY 09/2011; 61(Pt 9):2081-8. · 2.11 Impact Factor
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ABSTRACT: A scale-down investigation of the impact of local dissolved oxygen limitation on lipase production by Y. lipolytica has been performed. One of the major issues encountered during this kind of process is foam formation, requiring a reduction of the overall oxygen transfer efficiency of the system in order to keep antifoam consumption to a reasonable level. A regulation strategy involving oxygen enrichment of the air flow through the reactor has allowed this issue to be partly overcome. For a second time, the scale dependency of the process operated with air enrichment has been investigated by a combination of scale-down and pilot-scale cultivation tests. The scale-down apparatus considered in this work comprised a well-mixed part connected to a plug-flow part subjected to dissolved oxygen limitation. Surprisingly, foaming intensity was greatly reduced in the case of the test performed in scale-down reactors (SDRs) while maintaining the same stirring and aeration intensities in the stirred part of the reactor. For mean residence time of 100 s in the recycle loop of the reactor, foam formation was significantly reduced while cell growth and lipase production were both unaltered. When the residence time in the recycle loop was raised to 200 s, the foam phenomena was also reduced, but the lipase yield was altered as well as lip2 gene transcription and translation as shown by real-time quantitative polymerase chain reaction (RT-qPCR) and reporter gene activity, respectively. Our results clearly show the importance of primarily taking into account cell physiology for the scaling-up procedure.
Journal of Industrial Microbiology 08/2011; 39(2):337-46. · 1.80 Impact Factor
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ABSTRACT: The yeast Yarrowia lipolytica degrades efficiently low-cost hydrophobic substrates for the production of various added-value products such as lipases. To obtain yeast strains producing high levels of extracellular lipase, Y. lipolytica DSM3286 was subjected to mutation using ethyl methanesulfonate (EMS) and ultraviolet (UV) light. Twenty mutants were selected out of 1600 mutants of Y. lipolytica treated with EMS and UV based on lipase production ability on selective medium. A new industrial medium containing methyl oleate was optimized for lipase production. In the 20 L bioreactor containing new industrial medium, one UV mutant (U6) produced 356 U/mL of lipase after 24h, which is about 10.5-fold higher than that produced by the wild type strain. The properties of the mutant lipase were the same as those of the wild type: molecular weight 38 kDa, optimum temperature 37°C and optimum pH 7. Furthermore, the nucleotide sequences of extracellular lipase gene (LIP2) in wild type and mutant strains were determined. Only two silent substitutions at 362 and 385 positions were observed in the ORF region of LIP2. Two single substitutions and two duplications of the T nucleotide were also detected in the promoter region. LIP2 sequence comparison of the Y. lipolytica DSM3286 and U6 strains shows good targets to effective DNA recombinant for extracellular lipase of Y. lipolytica.
New Biotechnology 02/2011; 28(6):756-60. · 2.76 Impact Factor
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ABSTRACT: β-Glucosidases are widely distributed in living organisms and play a major role in the degradation of wood, hydrolysing cellobiose or cello-oligosaccharides to glucose. Termites are among the rare animals capable of digesting wood, thanks to enzyme activities of their own and to enzymes produced by their gut microbiota. Many bacteria have been identified in the guts of lower termites, some of which possess cellulolytic or/and hemicellulolytic activity, required for digesting wood. Here, having isolated bacterial colonies from the gut of Reticulitermes santonensis, we constructed in Escherichia coli a genomic DNA library corresponding to all of the colonies obtained and screened the library for clones displaying β-glucosidase activity. This screen revealed 8 positive clones. Sequence analysis with the BLASTX program revealed putative enzymes belonging to three glycoside hydrolase families (GH1, GH3 and GH4). Agar-plate tests and enzymatic assays revealed differences between the GH1- and GH3-type enzymes (as regards substrate specificity and regulation) and a difference in substrate specificity within the GH3 group. The substrate specificities and characteristic activities of these enzymes suggest that they may intervene in the depolymerisation of cellulose and hemicellulose.
Microbiological Research 02/2011; 166(8):629-42. · 2.31 Impact Factor
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ABSTRACT: Aphidius ervi (Hymenoptera: Braconidae) is an entomophagous parasitoid known to be an effective parasitoid of several aphid species of economic importance. A reduction of its production cost during mass rearing for inundative release is needed to improve its use in biological control of pests. In these contexts, a careful analysis of its entire development phases within its host is needed. This paper shows that this parasitoid has some characteristics in its embryological development rather complex and different from most other reported insects, which can be phylogenetically very close. First, its yolkless egg allows a high fecundity of the female but force them to hatch from the egg shell rapidly to the host hemocoel. An early cellularisation allowing a rapid differentiation of a serosa membrane seems to confirm this hypothesis. The serosa wraps the developing embryo until the first instar larva stage and invades the host tissues by microvilli projections and form a placenta like structure able to divert host resources and allowing nutrition and respiration of embryo. Such interspecific invasion, at the cellular level, recalls mammal's trophoblasts that anchors maternal uterine wall and underlines the high adaptation of A. ervi to develop in the host body.
PLoS ONE 01/2011; 6(4):e18847. · 4.09 Impact Factor
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ABSTRACT: The consumers' demand for natural flavour and fragrances rises. To be natural, compounds have to result from the extraction of natural materials and/or to be transformed by natural means such as the use of enzymes or whole cells. Fungi are able to transform some fatty acids into lactones that can thus be natural. Although some parts of this subject have been reviewed several times, the present article proposes to review the different pathways utilised, the metabolic engineering strategies and some current concerns on the reactor application of the transformation including scaling up data. The main enzymatic steps are hydroxylation and β-oxidation in the traditional way, and lactone desaturation or Baeyer-Villiger oxidation. Although the pathway to produce γ-decalactone is rather well known, metabolic engineering strategies may result in significant improvements in the productivity. For the production of other lactones, a key step is the hydroxylation of fatty acids. Beside the biotransformation, increasing the production of the various lactones requires from biotechnologists to solve two main problems which are the toxicity of lactones toward the producing cell and the aeration of the emulsified reactor as the biochemical pathway is very sensitive to the level of available oxygen. The strategies employed to resolve these problems will be presented.
Applied Microbiology and Biotechnology 10/2010; 89(3):535-47. · 3.42 Impact Factor
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ABSTRACT: Yarrowia lipolytica lipase has been assumed to be a good candidate for the treatment of fat malabsorption in patients with pancreatic insufficiency. Nevertheless, no systematic studies on its stability under physiological conditions pertaining to the human GI (gastrointestinal) tract have been published. Stability of various Y. lipolytica lipase powder formulations at various physiological pH values as well as the effect of digestive proteases and bile salts on enzyme activity were investigated. Results were compared with those obtained from another competing fungal lipase sourced from Candida rugosa. Among the studied formulations, Y. lipolytica lipase stabilized with gum arabic and skimmed milk powder was the most promising powder formulation. Under acidic conditions (pH 3-5), this formulation showed higher stability than those observed with the other Y. lipolytica lipase formulations and C. rugosa lipase. In addition, in the presence of gum arabic and skimmed milk powder as additives, Y. lipolytica lipase exhibited markedly higher resistance to pepsin, trypsin and chymotrypsin actions. Resistance to proteolytic degradation by digestive proteases was also by far higher than that observed with C. rugosa lipase. Similar behaviour was, however, observed when these two fungal lipases were incubated with increased concentrations of bile salts. Residual lipase activity of both fungal lipases showed a slight decrease in NaTDC (sodium taurodeoxycholate) concentration above 4 mM. Consequently, Y. lipolytica lipase formulated with gum arabic and milk powder seemed to have great potential for use as a therapeutic tool for patients with pancreatic insufficiency.
Biotechnology and Applied Biochemistry 10/2010; 57(4):139-49. · 1.53 Impact Factor
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ABSTRACT: Five spore-forming bacteria producer of lactic acid were isolated from soils sampled in the vicinity of poultry farms in Burkina Faso. All isolates were Gram-positive, motile, mesophilic, facultative anaerobic, catalase positive rods, and with L(+) lactic acid production. The isolates have been characterized and identified by a polyphasic approach, combining various phenotypic and genetic characteristics. The 16S-rDNA-sequence analyses revealed the membership of two isolates to the genus Bacillus and the three other to the genus Paenibacillus. The physiological and biochemical analyses showed that the isolates were quite different from known spore forming lactic acid bacteria. Several relevant technological properties were observed, particularly the resistance of the isolates to bile salts and acidic conditions, even the productions of amylolytic and proteolytic enzymes, which could make them good candidates for certain technological applications such as food fermentations and probiotic formulations. Furthermore, the isolation of these microorganisms in the vicinity of farms reinforces the feasibility of their involvement in animal feedstuffs preparations. In conclusion, this work shows an important diversity within the spore-forming lactic acid bacteria and confirms the conclusions of previous works, which have already shown that the SFLAB (Spore Forming Lactic Acid Bacteria) were good candidates for food fermentation and the probiotic formulations.
African journal of microbiology research 07/2010; 4:1016-1025. · 0.54 Impact Factor
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ABSTRACT: The protective effects of the fatty acid composition and membrane action of the acidification activity of two strains of Lactobacillus kept at 20 degrees C were studied. The addition of sorbitol, monosodium glutamate and glycerol during storage is causing the decline of acidification and increased concentrations of unsaturated fatty acids observed in both strains. The addition of sorbitol and monosodium glutamate does not alter the fatty acid composition, whatever the strain, but increases the resistance to freeze-drying of L. plantarum CWBI-B1419 and improves survival during storage. The addition of these preservatives and decreased activity of acidification improves the ratio unsaturated. These results indicate that the survival during storage and freeze-drying resistance are closely related to the composition of membrane fatty acids. This behaviour can be interpreted as an adaptation of L. plantarum B1419-CWBI supplemented by cryoprotectant additives such as sorbitol or monosodium glutamate sorbitol and monosodium glutamate as an additive. L. plantarum CWBI-B1419 presents a greater adaptation to culture conditions than L. paracasei ssp. paracasei LMG9192(T).
International Journal of Microbiology 01/2010; 2010:625239.
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ABSTRACT: During the biotransformation of castor oil into gamma-decalactone, R. aurantiaca produced both the lactone form and its precursor (4-hydroxydecanoic acid). After six days of culture, a maximum yield of gamma-decalactone of 6.5 g/l was obtained. The parameters of gamma-decalactone adsorption on three Macronet resins (MN-202, MN-102 and MN-100) were investigated in water. Adsorption isotherms of gamma-decalactone for the three Macronet resins were linear. The trapping of gamma-decalactone produced by R. aurantiaca on these resins was then carried out. gamma-Decalactone was effectively retained by all the studied Macronet resins. The resin MN-202 trapped gamma-decalactone more efficiently than MN-102 and MN-100. The percentages of gamma-decalactone adsorbed on the resins MN-202, MN-102 and MN-100 were, respectively, 85, 75 and 81%, whereas around 70% of the adsorbed gamma-decalactone was then desorbed. We propose an industrial process that uses Macronet resins to extract gamma-decalactone from culture broth of R. aurantiaca.
Journal of Industrial Microbiology 11/2009; 37(2):167-72. · 1.80 Impact Factor
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ABSTRACT: Lactococcus lactis subsp. lactis strain CWBI B1410, which produces various antibacterial compounds including organic acids and nisin, was used as a starter culture to improve the traditional Senegalese fish fermentation in which fish are mostly transformed to guedj by spontaneous fermentation for 24 to 48 h at ambient temperatures near 30 degrees C followed by salting (with NaCl) and sun drying. Assays were performed on lean fish (Podamasys jubelini) and fat fish (Arius heudelotii) purchased at a local market. The total viable microbial counts in raw fillets of P. jubelini and A. heudelotii were 5.78 and 5.39 log CFU/g, respectively. Populations of enteric bacteria (which can include pathogenic bacteria) in P. jubelini and A. heudelotii were 4.08 and 4.12 log CFU/g, respectively. Spontaneous fermentation of raw fillets at 30 degrees C led to the proliferation of enteric bacteria to 9 log CFU/g after 24 h in fermented P. jubelini and A. heudelotii fillets with pH values of 6.83 and 7.50, respectively. When raw fish fillets were supplemented with glucose (1%, wt/wt) and inoculated with Lactococcus lactis (10(7) CFU/g), the pH decreased to about 4.60 after 10 h at 30 degrees C, and nisin activity was detected in juice from the fillets. Traditionally fermented fillets of P. jubelini and A. heudelotii contained enteric bacteria at higher levels of 4 and 2 log CFU/g, respectively, than did fillets of the same fish supplemented with glucose and fermented with the starter culture. These data suggest that this new fish fermentation strategy combined with salting and drying can be used to enhance the safety of guedj.
Journal of food protection 09/2009; 72(9):1930-4. · 1.94 Impact Factor
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ABSTRACT: The production of gamma-decalactone and 4-hydroxydecanoic acid by the psychrophilic yeast R. aurantiaca was studied. The effect of both compounds on the growth of R. aurantiaca was also investigated and our results show that gamma-decalactone must be one of the limiting factors for its production. The addition of gum tragacanth to the medium at concentrations of 3 and 4 g/l seems to be an adequate strategy to enhance gamma-decalactone production and to reduce its toxicity towards the cell. The production of gamma-decalactone and 4-hydroxydecanoic acid was significantly higher in 20-l bioreactor than in 100-l bioreactor. By using 20 g/l of castor oil, 6.5 and 4.5 g/l of gamma-decalactone were extracted after acidification at pH 2.0 and distillation at 100 degrees C for 45 min in 20- and 100-l bioreactors, respectively. We propose a process at industrial scale using a psychrophilic yeast to produce naturally gamma-decalactone from castor oil which acts also as a detoxifying agent; moreover the process was improved by adding a natural gum.
Applied biochemistry and biotechnology 09/2009; 162(1):233-41. · 1.94 Impact Factor
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ABSTRACT: A starter culture is defined as a collection of microbial cells that are capable of initiating and completing a rapid fermentation
process. The microorganisms used as starter cultures in industrial applications, such as lactic acid bacteria and yeasts,
are usually conserved either in a frozen or a powdered form via the freeze-drying, spray-drying or fluidization processes
(To and Etzel, 1997). With regard to acetic acid bacteria (AAB), three forms of starter culture are used in vinegar making:
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Liquid inoculum used in the culture surface method or Orleans method, submerged method, or immobilization method (Ohmori et
al.,1982).
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Dried starter,as recently used by Sokollek et al.(1998)and Ndoye et al.(2007a) for submerged fermentation into Frings and
Chansard acetators,respectively.
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Vinegar made from wine,using mixed strains from raw materials (Gullo et al., 2006).
08/2009: pages 61-71;
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ABSTRACT: Among 18 psychrophilic strains isolated near the Antarctic Station, the psychrophilic strain Rhodotorula aurantiaca A19 was selected for its ability of growth and gamma-decalactone production at low temperatures. The effects of temperature, initial pH, and castor oil concentration on the growth and gamma-decalactone production by a psychrophilic and a mesophilic strain of R. aurantiaca were investigated. The highest gamma-decalactone production in flasks (5.8 g/l) was obtained with the strain A19 at 14 degrees C and initial pH 7.0 in medium containing 20 g/l castor oil. On the other hand, these factors did not affect the production of gamma-decalactone by the mesophilic strain. In fermentor, a gamma-decalactone concentration of 6.6 g/l was reached with the strain A19, whereas a maximum of 0.1 g/l was obtained with the mesophilic strain. Our results suggest that the ability to synthesize gamma-decalactone is a particularity of the strain A19, since the mesophilic strain (no. 30645) produced small amounts, and the other (no. 31354) did not exhibit this property. It is, to our knowledge, the first report of gamma-decalactone production by R. aurantiaca and furthermore by a psychrophilic yeast strain. Moreover, the amount of gamma-decalactone obtained in fermentor with the strain 19 was on the order of concentrations usually described in patents.
Applied biochemistry and biotechnology 07/2009; 158(1):41-50. · 1.94 Impact Factor
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Mario Aguedo,
Jean-Michel Giet,
Emilien Hanon,
Georges Lognay,
Bernard Wathelet, Jacqueline Destain,
Robert Brasseur,
Micheline Vandenbol,
Sabine Danthine,
Christophe Blecker,
Jean-Paul Wathelet
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ABSTRACT: Milk fat (MF) and rapeseed oil (RO) blends were analyzed by differential scanning calorimetry (DSC). It was shown that peak and onset temperatures can be used to determine the percentage of each fat in the blend and that the relative enthalpy of one peak assigned to low-melting triacylglycerols (TAG) can also be used to determine the percentage of RO in the blend. A linear relation was also established between MF content of the blend and its dropping point (DP), indicating that DP can be linearly related with the above DSC data. A blend of MF/RO 70 : 30 (wt/wt) was then chosen as a model system for enzymatic interesterification (EIE). The applicability of DSC analyses to EIE products was checked and a correct correlation could be established between DSC values and the interesterification degree and DP. Among the data from the DSC profiles, the peak associated with low-melting TAG was the best indicator of the reaction course. In the same way, a high-melting MF stearin fraction was interesterified with RO. In that case, onset temperatures and peak “a” were better reaction indicators than for the interesterified MF/RO blend. We therefore suggest that values from DSC endotherms could be used to monitor EIE of fat blends.
European Journal of Lipid Science and Technology 03/2009; 111(4):376 - 385. · 1.73 Impact Factor
