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BackgroundIn order to produce an effective callus in Echinacea purpurea L.; determination of the explant type and growth regulators that best respond to callus induction and the optimization of the culture conditions to increase the amount of caffeic acid derivatives (CADs) in the obtained callus. CADs contents of callus cultures of E. purpurea were evaluated by establishing an effective callus induction system in vitro.ResultsVarious medium containing different growth regulators were tested using leaf, petiole, cotyledon and root as the explants. The best callus development was achieved in MS medium with 1.0 mg l−1 2,4-D + 2.0 mg l−1 BAP in leaf, 1.0 mg l−1 NAA + 0.5 mg l−1 TDZ in petiole, 2.0 mg l−1 NAA + 1.0 mg l−1 TDZ in cotyledon and 0.5 mg l−1 NAA + 0.5 mg l−1 BAP in roots. Upon optimisation of callus growth, each type of explant was cultured for 4, 6, 8 and 10 weeks in medium for the analyses of caftaric acid, chlorogenic acid, caffeic acid and chicoric acid contents. The highest amounts of caftaric acid (4.11 mg/g) and chicoric acid (57.89 mg/g) were found from petiole explants and chlorogenic acid (8.83 mg/g) from root explants at the end of the 10-week culture time.ConclusionsAs a result of the present study, the production of caffeic acid derivatives was performed by providing the optimization of E. purpurea L. callus cultures. Effective and repeatable protocols established in this study may offer help for further studies investigating the production of caffeic acid derivatives in vitro.How to cite: Tanur Erkoyuncu M, Yorgancilar M. Optimization of callus cultures at Echinacea purpurea L. for the amount of caffeic acid derivatives. Electron J Biotechnol 2021;51. https://doi.org/10.1016/j.ejbt.2021.02.003. 相似文献
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BackgroundEthanol concentration (PE), ethanol productivity (QP) and sugar consumption (SC) are important values in industrial ethanol production. In this study, initial sugar and nitrogen (urea) concentrations in sweet sorghum stem juice (SSJ) were optimized for high PE (≥ 10%, v/v), QP, (≥ 2.5 g/L·h) and SC (≥ 90%) by Saccharomyces cerevisiae SSJKKU01. Then, repeated-batch fermentations under normal gravity (NG) and high gravity (HG) conditions were studied.ResultsThe initial sugar at 208 g/L and urea at 2.75 g/L were the optimum values to meet the criteria. At the initial yeast cell concentration of ~ 1 × 108 cells/mL, the PE, QP and SC were 97.06 g/L, 3.24 g/L·h and 95.43%, respectively. Repeated-batch fermentations showed that the ethanol production efficiency of eight successive cycles with and without aeration were not significantly different when the initial sugar of cycles 2 to 8 was under NG conditions (~ 140 g/L). Positive effects of aeration were observed when the initial sugar from cycle 2 was under HG conditions (180–200 g/L). The PE and QP under no aeration were consecutively lower from cycle 1 to cycle 6. Additionally, aeration affected ergosterol formation in yeast cell membrane at high ethanol concentrations, whereas trehalose content under all conditions was not different.ConclusionInitial sugar, sufficient nitrogen and appropriated aeration are necessary for promoting yeast growth and ethanol fermentation. The SSJ was successfully used as an ethanol production medium for a high level of ethanol production. Aeration was not essential for repeated-batch fermentation under NG conditions, but it was beneficial under HG conditions.How to cite: Sriputorn B, Laopaiboon P, Phukoetphim N, et al. Enhancement of ethanol production efficiency in repeated-batch fermentation from sweet sorghum stem juice: Effect of initial sugar, nitrogen and aeration. Electron J Biotechnol 2020;46. https://doi.org/10.1016/j.ejbt.2020.06.001 相似文献
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BackgroundAlthough bioactive metabolites capable of causing oxidative photo-necrosis in plant tissues have been identified in fungi, little is known about this type of mechanism in bacteria. These metabolites act as photosensitizers that generate reactive oxygen species (ROS) capable of causing damage to cells. In addition, these metabolites can pass into an energetically excited state when they receive some luminous stimulus, a condition in which they interact with other molecules present in the environment, such as molecular oxygen (O2), also known as triplet oxygen (3O2), generating ROS.ResultsThe suspension of the bacterial culture of Pseudomonas cedrina was shown to produce foliar necrosis in papaya leaves (Carica papaya L.) only in the presence of sunlight, which is evidence of photosensitizing mechanisms that generate singlet oxygen (1O2). From the chemical study of extracts obtained from this bacteria, 3-(4-(2-carboxipropyl) phenyl) but-2-enoic acid (1) was isolated. This compound, in the presence of light and triplet oxygen (3O2), was able to oxidize ergosterol to its peroxide, since it acted as a photosensitizer producing 1O2, with which it was corroborated that a photosensitization reaction occurs, mechanism by which this bacterium could prove to cause oxidative foliar photo-necrosis.ConclusionsP. cedrina was able to induce oxidative foliar photo-necrosis because of its potential ability to produce photosensitizing metabolites that generate singlet oxygen in the plants it colonizes. Based on the above, it can be proposed that some bacteria can cause oxidative foliar photo-necrosis as an important mechanism in the pathogenesis of host species.How to cite: Mendoza G, Sánchez-Tafolla L, Trigos A. Oxidative foliar photo-necrosis produced by the bacteria Pseudomonas cedrina. Electron J Biotechnol 2020;44. https://doi.org/10.1016/j.ejbt.2020.01.007 相似文献
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BackgroundLiquid wax esters are widely used in cosmetic as well as pharmaceutical and other industries. The demand of organic and natural products is increasing nowadays. Coconut oil contains benefit fatty acids and has been mainly used for oil-based and moisturizer products. Liquid wax esters from coconut oil and unsaturated fatty alcohol can be synthesized by enzymatic reaction; and it is interesting for using as an alternative natural ingredient in these industries.ResultsOptimal condition for coconut oil based wax ester synthesis by immobilized lipase EQ3 was 10 U of enzyme, temperature at 30°C and molar ratio of coconut oil to oleyl alcohol at 1:3 (mol/mol) (0.33X) dissolved in isooctane for 12 h, while for Lipozyme RM IM optimal condition was 10 U of enzyme, temperature at 45°C and oil/alcohol molar ratio at 1:3 (0.33X) dissolved in isooctane for 3 h. Percentage of wax esters synthesized by both lipases reached more than 88%. Both immobilized lipases catalyzed high yield of wax esters within the 2nd batch; after that, the immobilized lipases showed reduced activity and synthesized < 60% of wax esters from the 3rd to 5th batch. The main composition of wax esters was ~ 48% oleyl laurate with 10% degradation at ~ 250°C.ConclusionsThe liquid wax ester synthesis by commercial Lipozyme RM IM had higher effect than immobilized lipase EQ3, but both catalysts were stable within 2 batches in the optimum condition. The characteristic properties of wax esters showed potential for use as components in cosmetics and skin care products.How to citeUngcharoenwiwat P, H-Kittikun A. Enzymatic synthesis of coconut oil based wax esters by immobilized lipase EQ3 and commercial lipozyme RMIM. Electron J Biotechnol 2020;47. https://doi.org/10.1016/j.ejbt.2020.06.005 相似文献
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BackgroundMilk whey, a byproduct of the dairy industry has a negative environmental impact, can be used as a raw material for added-value compounds such as galactooligosaccharides (GOS) synthesis by β-galactosidases.ResultsB-gal42 from Pantoea anthophila strain isolated from tejuino belonging to the glycosyl hydrolase family GH42, was overexpressed in Escherichia coli and used for GOS synthesis from lactose or milk whey. Crude cell-free enzyme extracts exhibited high stability; they were employed for GOS synthesis reactions. In reactions with 400 g/L lactose, the maximum GOS yield was 40% (w/w) measured by HPAEC-PAD, corresponding to 86% of conversion. This enzyme had a strong predilection to form GOS with β(1 → 6) and β(1 → 3) galactosyl linkages. Comparing GOS synthesis between milk whey and pure lactose, both of them at 300 g/L, these two substrates gave rise to a yield of 38% (60% of lactose conversion) with the same product profile determined by HPAEC-PAD.ConclusionsB-gal42 can be used on whey (a cheap lactose source) to produce added value products such as galactooligosaccharides.How to cite: Yañez-Ñeco CV, Cervantes FV, Amaya-Delgado L, et al. Synthesis of β(1→3) and β(1→6) galactooligosaccharides from lactose and whey using a recombinant β-galactosidase from Pantoea anthophila. Electron J Biotechnol 2021;49. https://dx.doi.org/10.1016/j.ejbt.2020.10.004 相似文献
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BackgroundL-tert-Leucine has been widely used in pharmaceutical, chemical, and other industries as a vital chiral intermediate. Compared with chemical methods, enzymatic methods to produce L-tert-leucine have unparalleled advantages. Previously, we found a novel leucine dehydrogenase from the halophilic thermophile Laceyella sacchari (LsLeuDH) that showed good thermostability and great potential for the synthesis of L-tert-leucine in the preliminary study. Hence, we manage to use the LsLeuDH coupling with a formate dehydrogenase from Candida boidinii (CbFDH) in the biosynthesis of L-tert-leucine through reductive amination in the present study.ResultThe double-plasmid recombinant strain exhibited higher conversion than the single-plasmid recombinant strain when resting cells cultivated in shake flask for 22 h were used. Under the optimized conditions, the double-plasmid recombinant E. coli BL21 (pETDute-FDH-LDH, pACYCDute-FDH) transformed 1 mol·L-1 trimethylpyruvate (TMP) completely into L-tert-leucine with greater than 99.9% ee within 8 h.ConclusionsThe LsLeuDH showed great ability to biosynthesize L-tert-leucine. In addition, it provided a new option for the biosynthesis of L-tert-leucine.How to citeWang L, Zhu W, Gao Z, et al. Biosynthetic L-tert-leucine using Escherichia coli co-expressing a novel NADH-dependent leucine dehydrogenase and a formate dehydrogenase. Electron J Biotechnol 2020;47. https://doi.org/10.1016/j.ejbt.2020.07.001 相似文献
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Establishment of a production process for a novel vaccine candidate against Lawsonia intracellularis
BackgroundLawsonia intracellularis remains a problem for the swine industry worldwide. Previously, we designed and obtained a vaccine candidate against this pathogen based on the chimeric proteins: OMP1c, OMP2c, and INVASc. These proteins formed inclusion bodies when expressed in E. coli, which induced humoral and cellular immune responses in vaccinated pigs. Also, protection was demonstrated after the challenge. In this study, we established a production process to increase the yields of the three antigens as a vaccine candidate.ResultsBatch and fed-batch fermentations were evaluated in different culture conditions using a 2 L bioreactor. A fed-batch culture with a modified Terrific broth medium containing glucose instead of glycerol, and induced with 0.75 mM IPTG at 8 h of culture (11 g/L of biomass) raised the volumetric yield to 627.1 mg/L. Under these culture conditions, plasmid-bearing cells increased by 10% at the induction time. High efficiency in cell disruption was obtained at passage six using a high-pressure homogenizer and a bead mill. The total antigen recovery was 64% (400 mg/L), with a purity degree of 70%. The antigens retained their immunogenicity in pigs, inducing high antibody titers.ConclusionsConsidering that the antigen production process allowed an increment of more than 70-fold, this methodology constitutes a crucial step in the production of this vaccine candidate against L. intracellularis.How to cite: Salazar S, Gutiérrez N, Sánchez O, et al. Establishment of a production process for a novel vaccine candidate against Lawsonia intracellularis. Electron J Biotechnol 2021.https://doi.org/10.1016/j.ejbt.2021.01.002 相似文献
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BackgroundCecropin P1, acting as an antimicrobial, has a broad-spectrum antibacterial activity with some antiviral and antifungal properties. It is a promising natural alternative to antibiotics which is originally isolated from the pig intestinal parasitic nematode Ascaris suum. Many studies have shown that Cecropin P1 is helpful for the prevention or treatment of clinical diseases. Therefore, it is very necessary to establish a safe, nontoxic, and efficient expression method of Cecropin P1.ResultsThe results indicated that the recombinant protein was about 5.5 kDa showed by Tricine–SDS–PAGE and Western blot. And Cecropin P1 was efficiently secreted and expressed after 12 h of induction, with an increasing yield over the course of the induction. Its maximum concentration was 7.83 mg/L after concentration and purification. In addition, in vitro experiments demonstrated that Cecropin P1 not only exerted a strong inhibitory effect on Escherichia coli, Salmonella sp., Shigella sp., and Pasteurella sp., but also displayed an antiviral activity against PRRSV NADC30-Like strain.ConclusionsCollectively, the strategy of expressing Cecropin P1 in Saccharomyces cerevisiae is harmless, efficient, and safe for cells. In addition, the expressed Cecropin P1 has antiviral and antibacterial properties concurrently.How to cite: Jiang R, Zhang P, Wu X, et al., Expression of antimicrobial peptide Cecropin P1 in Saccharomyces cerevisiae and its antibacterial and antiviral activity in vitro. Electron J Biotechnol 2021;50. https://doi.org/10.1016/j.ejbt.2020.12.006 相似文献
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BackgroundThis research is intended to determine suitable types and concentrations of plant growth regulators (PGRs) to induce callus on stem and leaf sections of 4 species of the genus Garcinia, namely, Garcinia mangostana, Garcinia schomburgkiana, Garcinia cowa, and Garcinia celebica. The base medium was MS medium containing 30 g l-1 sucrose, 0.5 g l-1 polyvinylpyrrolidone (PVP), and 7 g l-1 agar, and for the different treatments, PGRs were added to the medium as follows: thidiazuron (TDZ) at concentrations of 0, 0.1, 0.5, 1, and 2 mg l-1; 6-(3-hydroxybenzylamino) purine (meta-topolin) at concentrations of 0, 0.5, 2.5, and 5 mg l-1; 4-amino-3,5,6-trichloro-2-pyridinecarboxylic acid (picloram) at concentrations of 0, 0.5, 2.5, and 5 mg l-1; and 2,4-dichlorophenoxyacetic acid (2,4-D) at concentrations of 0, 0.5, 1, 2, and 4 mg l-1. The occurrence of callus was observed after 4 weeks.ResultsA maximum of 100% and 93% of G. mangostana leaf explants formed callus in the 0.5 mg l-1 and 1 mg l-1 TDZ treatments, respectively, while 100% of G. schomburgkiana stem explants formed callus in the 1 mg l-1 TDZ treatment and 89% of G. schomburgkiana leaf explants formed callus in the 0.5 mg l-1 picloram treatment. The highest callus induction rate for G. cowa was 62% in the 1 mg l-1 TDZ treatment and for G. celebica was 56% in the 0.5 mg l-1·mT-1 treatment.ConclusionsFor all 4 species, the greatest amount of large nodular callus was observed in the TDZ treatments. White, friable callus was observed on most of the 2,4-D and picloram treatment groups. Most meta-topolin treatments resulted in minimal callus formation.How to cite: Suwanseree V, Phansiri S, Yapwattanaphun C. A comparison of callus induction in 4 Garcinia species. Electron J Biotechnol 2019;40. https://doi.org/10.1016/j.ejbt.2019.04.006 相似文献
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BackgroundFuels and chemicals from renewable feedstocks have a growing demand, and acetone, butanol and ethanol (ABE) are some relevant examples. These molecules can be produced by the bacterial fermentation process using hydrolysates generated from lignocellulosic biomass as sugarcane bagasse, one of the most abundant sources of lignocellulosic biomass in Brazil. It originates as a residue in mills and distilleries in the production of sugar and ethanol.ResultsIn the present work, two strategies to generate hydrolysates of sugarcane bagasse were adopted. The fermentation of the first hydrolysate by Clostridium acetobutylicum DSM 6228 resulted in final concentrations of butanol, acetone and ethanol of 6.4, 4.5 and 0.6 g/L, respectively. On the other hand, the second hydrolysate presented better results (averages of 9.1, 5.5 and 0.8 g/L, respectively), even without the need for nutrient supplementation, since key elements were already present in the medium. The productivity (QP) and yield (YP/S) of the solvents with second hydrolysate were 0.5 g/L·h-1 and 0.4 g/g, respectively.ConclusionsThe results described herein open new perspectives for the production of important molecules from residual lignocellulosic biomass for the fuel and chemical industries within the context of second-generation biorefinery.How to cite: Gomes AC, Rodrigues MI, Passos DF, et al. Acetone-butanol-ethanol fermentation from sugarcane bagasse hydrolysates: utilization of C5 and C6 sugars. Electron J Biotechnol 2019;42. https://doi.org/10.1016/j.ejbt.2019.10.004. 相似文献
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Identification and characterization of a novel 2R,3R-Butanediol dehydrogenase from Bacillus sp. DL01
Background2R,3R-butanediol dehydrogenase (R-BDH) and other BDHs contribute to metabolism of 3R/3S-Acetoin (3R/3S-AC) and 2,3-butanediol (2,3-BD), which are important bulk chemicals used in different industries. R-BDH is responsible for oxidizing the hydroxyl group at their (R) configuration. Bacillus species is a promising producer of 3R/3S-AC and 2,3-BD. In this study, R-bdh gene encoding R-BDH from Bacillus sp. DL01 was isolated, expressed and identified.ResultsR-BDH exerted reducing activities towards Diacetyl (DA) and 3R/3S-AC using NADH, and oxidizing activities towards 2R,3R-BD and Meso-BD using NAD+, while no activity was detected with 2S,3S-BD. The R-BDH showed its activity at a wide range of temperature (25°C to 65°C) and pH (5.0–8.0). The R-BDH activity was increased significantly by Cd2+ when DA, 3R/3S-AC, and Meso-BD were used as substrates, while Fe2+ enhanced the activity remarkably at 2R,3R-BD oxidation. Kinetic parameters of the R-BDH from Bacillus sp. DL01 showed the lowest Km, the highest Vmax, and the highest Kcat towards the racemic 3R/3S-AC substrate, also displayed low Km towards 2R,3R-BD and Meso-BD when compared with other reported R-BDHs.ConclusionsThe R-BDH from Bacillus sp. DL01 was characterized as a novel R-BDH with high enantioselectivity for R-configuration. It considered NAD+ and Zn2+ dependant enzyme, with a significant affinity towards 3R/3S-AC, 2R,3R-BD, and Meso-BD substrates. Thus, R-BDH is providing an approach to regulate the production of 3R/3S-AC or 2,3-BD from Bacillus sp. DL01.How to cite: Elmahmoudy M, Elfeky N, Zhongji P, et al. Identification and characterization of a novel 2R,3R-Butanediol Dehydrogenase from Bacillus sp. DL01. Electron J Biotechnol 2021;49. https://doi.org/10.1016/j.ejbt.2020.11.002 相似文献
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BackgroundAn efficient regeneration protocol is a priority for the successful application of plant biotechnology. Grape nodal explants were used to develop a micropropagation protocol for Thompson Seedless and Taify cvs. Explants were cultured on MS medium supplemented with Kinetin or benzylaminopurine (BA) and indolebutyric acid (IBA).ResultsFor both cultivars, axillary buds were grown, only, on a medium enriched with kinetin, moreover, shoot tip necrosis and callus formation were observed on Thompson Seedless cv. cultures grown on a medium with BA. Supplementing the growth medium with 100 mM (boron) B and 2.5 mM (calcium) Ca successfully help overcome these phenomena. The highest regenerated shoot numbers (14 and 6.2 explant−1) for Taify and Thompson Seedless cvs., respectively, were on media supplemented with 13.2 µM BA + 4.9 µM IBA and BA 13.2 µM + 5.8 µM IBA, respectively. Moreover, these media supported the developing shoots to have the heaviest dry weights (1.46 and 0.72 mg explant−1) for Taify and Thompson Seedless cvs., respectively. Thompson Seedless cv. regenerated shoot numbers and their dry weights were significantly increased by increasing the MS medium PO4− concentration. However, these two parameters were significantly decreased for Taify cv. Developing shoots were elongated and rooted on MS medium enriched with 4.9 µM, IBA 100 mM B and 2.5 mM Ca. Plantlets were acclimatized and successfully transferred to the greenhouse conditions.ConclusionsA novel promising protocol for Thomson Seedless and Taify cvs. micropropagation using single nodes has been developed.How to cite: Al-Aizari AA, Al-Obeed RS, Mohamed MA-H. Improving micropropagation of some grape cultivars via boron, calcium and phosphate. Electron J Biotechnol 2020;49. https://doi.org/10.1016/j.ejbt.2020.10.001 相似文献
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BackgroundOpsonization, is the molecular mechanism by which target molecules promote interactions with phagocyte cell surface receptors to remove unwanted cells by induced phagocytosis. We designed an in vitro system to demonstrate that this procedure could be driven to eliminate adipocytes, using peptides mimicking regions of the complement protein C3b to promote opsonization and enhance phagocytosis. Two cell lines were used: (1) THP-1 monocytes differentiated to macrophages, expressing the C3b opsonin receptor CR1 in charge of the removal of unwanted coated complexes; (2) 3T3-L1 fibroblasts differentiated to adipocytes, expressing AQP7, to evaluate the potential of peptides to stimulate opsonization. (3) A co-culture of the two cell lines to demonstrate that phagocytosis could be driven to cell withdrawal with high efficiency and specificity.ResultsAn array of peptides were designed and chemically synthesized p3691 and p3931 joined bound to the CR1 receptor activating phagocytosis (p < 0.033) while p3727 joined the AQP7 protein (p < 0.001) suggesting that opsonization of adipocytes could occur. In the co-culture system p3980 and p3981 increased lipid uptake to 91.2% and 89.0%, respectively, as an indicator of potential adipocyte phagocytosis.ConclusionsThis in vitro model could help understand the receptor–ligand interaction in the withdrawal of unwanted macromolecules in vivo. The adipocyte-phagocytosis discussed may help to control obesity, since peptides of C3b stimulated the CR1 receptor, promoting opsonisation and phagocytosis of lipid-containing structures, and recognition of AQP7 in the differentiated adipocytes, favored the phagocytic activity of macrophages, robustly supported by the co-culture strategy.How to cite: Bartsch IM, Perelmuter K, Bollati-Fogolin M, et al. An in vitro model mimicking the complement system to favor directed phagocytosis of unwanted cells. Electron J Biotechnol 2021;49. https://doi.org/10.1016/j.ejbt.2020.09.010. 相似文献
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BackgroundOleaginous yeasts can be grown on different carbon sources, including lignocellulosic hydrolysate containing a mixture of glucose and xylose. However, not all yeast strains can utilize both the sugars for lipogenesis. Therefore, in this study, efforts were made to isolate dual sugar-utilizing oleaginous yeasts from different sources.ResultsA total of eleven isolates were obtained, which were screened for their ability to utilize various carbohydrates for lipogenesis. One promising yeast isolate Trichosporon mycotoxinivorans S2 was selected based on its capability to use a mixture of glucose and xylose and produce 44.86 ± 4.03% lipids, as well as its tolerance to fermentation inhibitors. In order to identify an inexpensive source of sugars, nondetoxified paddy straw hydrolysate (saccharified with cellulase), supplemented with 0.05% yeast extract, 0.18% peptone, and 0.04% MgSO4 was used for growth of the yeast, resulting in a yield of 5.17 g L−1 lipids with conversion productivity of 0.06 g L−1 h−1. Optimization of the levels of yeast extract, peptone, and MgSO4 for maximizing lipid production using Box–Behnken design led to an increase in lipid yield by 41.59%. FAME analysis of single cell oil revealed oleic acid (30.84%), palmitic acid (18.28%), and stearic acid (17.64%) as the major fatty acids.ConclusionThe fatty acid profile illustrates the potential of T. mycotoxinivorans S2 to produce single cell oil as a feedstock for biodiesel. Therefore, the present study also indicated the potential of selected yeast to develop a zero-waste process for the complete valorization of paddy straw hydrolysate without detoxification.How to cite: Sagia S, Sharma A, Singh S, et al. Single cell oil production by a novel yeast Trichosporon mycotoxinivorans for complete and ecofriendly valorization of paddy straw. Electronic Journal of Biotechnology 2020;44. https://doi.org/10.1016/j.ejbt.2020.01.009. 相似文献
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BackgroundPhospholipase D (PLD) is used as the biocatalyst for phosphatidylserine (PS) production. In general, PLD was expressed in insoluble form in Escherichia coli. High-level soluble expression of PLD with high activity in E. coli is very important for industrial production of PLD.ResultsStreptomyces chromofuscus PLD coding gene was codon-optimized, cloned without signal peptide, and expressed in E. coli. The optimal recombinant E. coli pET-28a+PLD/BL21(DE3) was constructed with pET-28a without His-tag. The highest PLD activity reached 104.28 ± 2.67 U/mL in a 250-mL shake flask after systematical optimization. The highest PLD activity elevated to 122.94 ± 1.49 U/mL by feeding lactose and inducing at 20°C after scaling up to a 5.0-L fermenter. Substituting the mixed carbon source with 1.0 % (w/v) of cheap dextrin and adding a feeding medium could still attain a PLD activity of 105.81 ± 2.72 U/mL in a 5.0-L fermenter. Fish peptone from the waste of fish processing and dextrin from the starch are both very cheap, which were found to benefit the soluble PLD expression.ConclusionsAfter combinatorial optimization, the high-level soluble expression of PLD was fulfilled in E. coli. The high PLD activity along with cheap medium obtained at the fermenter level can completely meet the requirements of industrial production of PLD.How to cite: Wu R, Cao J, Liu F, et al. High-level soluble expression of phospholipase D from Streptomyces chromofuscus in Escherichia coli by combinatorial optimization. Electron J Biotechnol 2021;50.https://doi.org/10.1016/j.ejbt.2020.12.002 相似文献
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BackgroundDiabetes is a metabolic disorder caused by defects in insulin production and activity. During disease progression, changes in lipid peroxidation cause structural modifications via production of free radicals. Fangchinoline is a well-known alkaloid present in Stephaniae tetrandrine S. Moore, which has demonstrated antioxidant, anticancer, and anti-inflammatory activities.ResultsThe present study analyzed the anti-diabetic and antioxidant effects of fangchinoline in male rats with streptozotocin-induced diabetes. Rats were divided into the following groups: normal control, diabetic, diabetic + fangchinoline 100 mg/kg, diabetic + fangchinoline 200 mg/kg and diabetic + glibenclamide 600 µg/kg. The treatment was administered orally for 45 consecutive days. Lipid peroxidation was substantially increased by >50% in the serum, as well as the liver, kidney, and heart tissues of diabetic rats. However, fangchinoline supplementation significantly reduced lipid peroxidation to near normal levels. Reactive oxygen species levels were substantially increased by >500% in the serum, as well as the liver, kidney, and heart tissues of diabetic rats. Fangchinoline supplementation reduced reactive oxygen species to near normal levels. Fangchinoline supplementation significantly improved superoxide dismutase, glutathione peroxidase, catalase, and reduced glutathione levels in diabetic rats. Total hexoses, sialic acid, hexosamines, and fucose were increased in diabetic rats, whereas fangchinoline supplementation significantly reduced these total hexoses, sialic acid, hexosamines, and fucose to near normal levelsConclusionsSupplementation with fangchinoline led to significant attenuation of the levels of lipid peroxidation, ROS, and glycoprotein components such as total hexoses, hexosamines, sialic acid, and fucose, while improving antioxidant marker levels.How to cite: Xia J, Huang W, Zhou F. Effect of fangchinoline on oxidant status in male albino rats with streptozotocin-induced diabetes. Electron J Biotechnol 2021;53. https://doi.org/10.1016/j.ejbt.2021.07.005 相似文献