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Two new torrubiellin derivatives, parengyomarin A (1) and parengyomarin B (2), together with three known compounds torrubiellin B (3), emodin (4), and emodic acid (5) were isolated from the mangrove endophytic fungus Parengyodontium album. Their structures were elucidated through NMR and MS analysis, and by comparison with literature data. Three torubiellin derivatives (1–3) showed significant antibacterial activity against Staphylococcus aureus and MRSA with MIC values of 0.39∼3.12 μM.

Vernalization is the process of exposure to low temperatures, which is crucial for the transition from vegetative to reproductive growth of plants. In this study, the global landscape vernalization-related mRNAs and long noncoding RNAs (lncRNAs) were identified in

Fengycin is a lipopeptide produced by

Fengycin is a lipopeptide produced by Bacillus that has a strong inhibitory effect on filamentous fungi; however, its use is restricted due to poor production and low yield. Previous studies have shown that fengycin biosynthesis in B. amyloliquefaciens was found to be significantly increased after fructose addition. This study investigated the effect of fructose on fengycin production and its regulation mechanism in B. amyloliquefaciens by transcriptome sequencing. According to the RNA sequencing data, 458 genes were upregulated and 879 genes were downregulated. Transcriptome analysis results showed that fructose changed the transcription of amino acid synthesis, fatty acid metabolism, and energy metabolism; alterations in these metabolic pathways contribute to the synthesis of fengycin. In an MLF medium (modified Landy medium with fructose), the expression level of the fengycin operon was two-times higher than in an ML medium (modified Landy medium). After fructose was added to B. amyloliquefaciens, the fengycin-synthesis-associated genes were activated in the process of fengycin synthesis.

Herein, a bactericide-secreting Bacillus strain, potentially useful as a biocontrol agent, was isolated from the commercial Yanjing Natto food. Following the biochemical and physiological evaluation, the molecular identification was performed using 16S rDNA sequencing of polymerase chain reaction-amplified DNA that confirmed the natto isolate as Bacillus subtilis natto (B. subtilis natto). The biocontrol (microbial inhibitory) capability of B. subtilis natto was investigated against Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, and yeast (Yarrowia lipolytica) and recorded. The antimicrobial activity of B. subtilis natto was further enhanced by optimizing the growth medium for optimal bactericides secretion. Under optimized conditions, B. subtilis natto exhibited much higher inhibitory activity against S. aureus with a zone of inhibition diameter up to 27 mm. After 48 h incubation, the optimally yielded B. subtilis natto broth was used to extract and purify the responsible bactericides by silica gel column chromatography, gel column chromatography, and semi-preparative high-performance liquid chromatography. Structural identification of purified bactericides (designated as NT-5, NT-6, and NT-7) from B. subtilis natto was performed by 13C-nuclear magnetic resonance (NMR) and mass spectral analyses. The NMR comparison also revealed that NT-5, NT-6, and NT-7 had identical structures, except for the fatty chain. In summary, the present study suggests the improved biocontrol and/or microbial inhibitory potential of newly isolated bactericides secreting B. subtilis natto.

Current biorefinery approaches comprehend diverse biomass feedstocks and various conversion techniques to produce a variety of high-value biochemicals and biofuels. Lignocellulose is among the most abundant, bio-renewable, and sustainable bioresources on earth. It is regarded as a prodigious alternative raw feedstock to produce a large number of chemicals and biofuels. Producing biofuels and platform chemicals from lignocellulosic biomasses represent advantages in terms of energy and environmental perspectives. Lignocellulose is a main structural constituent of non-woody and woody plants consisting of lignin, cellulose, and hemicellulose. Efficient exploitation of all these components is likely to play a considerable contribution to the economic viability of the processes since lignocellulosic biomass often necessitate pretreatment for liberating fermentable sugars and added value products that might serve as feedstocks for microbial strains to produce biofuels and biochemicals. Developing robust microbial culture and advancements in metabolic engineering approaches might lead to the rapid construction of cell factories for the effective biotechnological transformation of biomass feedstocks to produce biorefinery products. In this comprehensive review, we discuss the recent progress in the valorization of agro-industrial wastes as prospective microbial feedstocks to produce a spectrum of high-value products, such as microbial pigments, biopolymers, industrial biocatalysts, biofuels, biologically active compounds, bioplastics, biosurfactants, and biocontrol agents with therapeutic and industrial potentialities. Lignocellulosic biomass architecture, compositional aspects, revalorization, and pretreatment strategies are outlined for efficient conversion of lignocellulosic biomass. Moreover, metabolic engineering approaches are briefly highlighted to develop cell factories to make the lignocellulose biorefinery platforms appealing.

Global warming issues, rapid fossil fuel diminution, and increasing worldwide energy demands have diverted accelerated attention in finding alternate sources of biofuels and energy to combat the energy crisis. Bioconversion of lignocellulosic biomass has emerged as a prodigious way to produce various renewable biofuels such as biodiesel, bioethanol, biogas, and biohydrogen. Ideal microbial hosts for biofuel synthesis should be capable of using high substrate quantity, tolerance to inhibiting substances and end-products, fast sugar transportation, and amplified metabolic fluxes to yielding enhanced fermentative bioproduct. Genetic manipulation and microbes' metabolic engineering are fascinating strategies for the economical production of next-generation biofuel from lignocellulosic feedstocks. Metabolic engineering is a rapidly developing approach to construct robust biofuel-producing microbial hosts and an important component for future bioeconomy. This approach has been widely adopted in the last decade for redirecting and revamping the biosynthetic pathways to obtain a high titer of target products. Biotechnologists and metabolic scientists have produced a wide variety of new products with industrial relevance through metabolic pathway engineering or optimizing native metabolic pathways. This review focuses on exploiting metabolically engineered microbes as promising cell factories for the enhanced production of advanced biofuels.

Fengycin, as a lipopeptide produced by Bacillus subtilis, displays potent activity against filamentous fungi, including Aspergillus flavus and Soft-rot fungus, which exhibits a wide range of potential applications in food industries, agriculture, and medicine. To better clarify the regulatory mechanism of fructose on fengycin biosynthesis, the iTRAQ-based proteomic analysis was utilized to investigate the differentially expressed proteins of B. amyloliquefaciens fmb-60 cultivated in ML (without fructose) and MLF (with fructose) medium. The results indicated that a total of 811 proteins, including 248 proteins with differential expression levels (162 which were upregulated (fold &gt, 2) and 86, which were downregulated (fold &lt, 0.5) were detected, and most of the proteins are associated with cellular metabolism, biosynthesis, and biological regulation process. Moreover, the target genes’ relative expression was conducted using quantitative real-time PCR to validate the proteomic analysis results. Based on the results of proteome analysis, the supposed pathways of fructose enhancing fengycin biosynthesis in B. amyloliquefaciens fmb-60 can be summarized as improvement of the metabolic process, including cellular amino acid and amide, fatty acid biosynthesis, peptide and protein, nucleotide and nucleobase-containing compound, drug/toxin, cofactor, and vitamin, reinforcement of peptide/protein translation, modification, biological process, and response to a stimulus. In conclusion, this study represents a comprehensive and systematic investigation of the fructose mechanism on improving fengycin biosynthesis in B. amyloliquefaciens, which will provide a road map to facilitate the potential application of fengycin or its homolog in defending against filamentous fungi.

The present study investigated the stimulation effect of L-glutamine (L-gln) on bacillomycin D biosynthesis of Bacillus subtilis fmbJ and the transcription of the synthetase genes and the signal proteins that related to the biosynthesis of bacillomycin D. It was found that L-gln significantly increased the production of bacillomycin D, in comparison with other amino acids. L-gln significantly enhanced the expression level of bmyA (BYA), bmyB (BYB), bmyC (BYC), the thioesterase gene (TE) and up-regulated DegU, σH and Spo0A, but down-regulated AbrB, therefore the yield of bacillomycin D significantly increased. Furthermore, when conjointly feeding 5 g/L of L-gln and 30 g/L of inulin, the production of bacillomycin D was up to 1.93 g/L.

Enzymatic hydration of oleic acid into 10-hydroxystearic acid (10-HSA) represents a theme of substantial scientific and practical interest. In this study, a fatty acid hydratase (OHase) from Lactococcus garvieae was cloned and expressed in Escherichia coli. The recombinantly expressed enzyme was identified as oleate hydratase (EC 4.2.1.53) confirming its highest hydration activity for oleic acid. The optimally yielded enzyme fraction was purified and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). A solitary band on SDS-PAGE confirmed the molecular weight of 65 kDa. Gas chromatography-mass spectrometry (GC-MS) analysis scrutinized the silylated hydroxy fatty acid products acquired from the hydration of oleic acid by the oleate hydratase from L. garvieae. Optimal reaction conditions for the enzymatic production of 10-HSA from oleic acid using the purified oleate hydratase were pH 7.5, 30 &deg, C, 105.49 U/mL enzyme solution and 30 g/L oleic acid. In the presence of activity stimulators, that is, magnesium (II) (Mg2+), the oleate hydratase activity was found to be greatly improved at 30 &deg, C. In conclusion, the results revealed the potential efficacy of recombinant enzyme for the biotechnological conversion of oleic acid to 10-HSA acid with high efficiency. The results would be useful for the improved industrial-scale biosynthesis of 10-HSA via an economical and environmentally friendly bioprocess approach.

The inhibition effects of bacillomycin D on the growth of Aspergillus ochraceus and the production of ochratoxin A (OTA) in food samples were investigated. The mycelia growth and sporulation were completely inhibited by 30 μg/mL of bacillomycin D. Microscopic morphological changes such as the distortion of hyphae and the disruption of spores at 20 μg/mL of bacillomycin D were significantly observed. The use of bacillomycin D resulted in cell damage, nucleic acids and proteins divulge, and more production of reactive oxygen species (ROS), and all these factors actively contributed to the promotion of apoptosis of A. ochraceus . In addition, 90 μg/g of bacillomycin D completely inhibited the growth of A. ochraceus and the production of OTA in food samples. Our results suggested that bacillomycin D showed a significant antifungal activity against A. ochraceus that could be used as a potential natural antimicrobial to control food contamination and ensure food safety.

This work provides an optimized extraction approach intended to maximize the recovery of dihydromyricetin (DHM) from Chinese vine tea (Ampelopsis grossedentata) leaves. The presented work adopts a Box-Behnken design as a response surface methodology to understand the role and influence of specific extraction parameters including: time, temperature, and solvent composition/ethanol (%) on DHM final yields. Initially, single factor experiments were used to delineate the role of above factors (temperature, time, and solvent composition) before proceeding with three factors-three levels Box-Behnken design with 17 separate runs to assess the effect of multifactorial treatments on DHM recovery rates. The collected data shows that independent variables (solvent composition, time, and temperature) can significantly affect DHM recovery rates with maximum yields resulting from a combined 60 °C, 60% aqueous ethanol, and 180 min treatment. From the empirical point of view, the above optimized extraction protocol can substantially enhance processing and profitability margins with a minimum need of interventions or associated costs.

Aims To explore the influence of carbohydrates on the production of fengycin by Bacillus amyloliquefaciens fmb-60. Methods and Results Fermentation and gene expression levels were examined following culture supplementation with fructose, arabinose and sorbitol. Compared with other carbohydrates, fructose most efficiently increased the concentration of the essential component amino acids for fengycin synthesis in the cell. The maximum production of fengycin was found to be 392.87 mg l-1, increased by 76% in fed-batch fermentation. Furthermore, fructose enhanced the biosynthesis of fengycin by increasing the expression of fengycin synthetase genes (fenA, fenB, fenC, fenD, fenE and fenTE) and regulatory genes (comA, degU, degQ and sigma H). Conclusion Fructose is important for fengycin production in B. amyloliquefaciens fmb-60, and it could enhance fengycin biosynthesis by raising the expression of the fengycin synthetase genes and upregulating signal factors. Significance and Impact of the Study The results identify regulatory mechanisms involved in fengycin biosynthesis and provide an effective method to enhance production of fengycin. This article is protected by copyright. All rights reserved.

Suppression subtractive hybridization (SSH) was used to clone transcripts upregulated during heat stress in leaves of Pinellia ternata. The complementary structures of deoxyribonucleic acid (cDNAs) of heat-stressed plants were used as the “tester,” and cDNAs of unstressed plants were used as the “driver.” Sequencing the whole SSH library yielded 303 expressed sequence tags (ESTs). Among these, 61 showed insignificant homology to any previously identified genes. Forty four of the remaining 242 ESTs represented singletons. Real-time quantitative reverse transcriptase polymerase chain reaction analysis of the expression patterns of four transcripts showed that three of these were upregulated after heat shock, and one was downregulated. The sequences showed high homology to small heat shock protein (sHSP), heat shock protein 90 (HSP90), heat shock protein 70 (HSP70), and stearoyl-ACP-protein desaturase (SAD), respectively. Rapid amplification of cDNA ends (RACE) was used to obtain full-length cDNAs of PtSAD and PtsHSP, and characterization and phylogenetic analyses were carried out according to their sequences.

The effect of inulin on the production of bacillomycin D and the levels of mRNA of bacillomycin D synthetase genes: bmyA (BYA), bmyB (BYB), bmyC (BYC), the thioesterase gene (TE) and regulating genes: AbrB, ComA, DegU, PhrC, SigmaH and Spo0A in Bacillus subtilis fmbJ were investigated. The production of bacillomycin D was enhanced with the increase of biomass concentration. The maximum production and productivity of bacillomycin D were found to be 1227.49 mg/L and 10.23 mg/L h. Inulin significantly improved the expression of bacillomycin D synthetase genes: bmyA (BYA), bmyB (BYB), bmyC (BYC) and the thioesterase gene (TE). Also, inulin up-regulated ComA, DegU, SigmaH and Spo0A and therefore promoted the high production of bacillomycin D. Our results provided a practical approach for efficient production of bacillomycin D and a meaningful explanation for regulatory mechanism of bacillomycin D biosynthesis.

Objective To determine the optimal concentration and processing time of EMS mutation for suspension cells from Pinellia ternata. Method Under four EMS concentration gradients (0.1% , 0.2%, 0.4%, 0.6%) and three processing time gradients (0.5, 1.0, 2.0 h), the suspension cells of P. ternata were mutagenized. Result and conclusion The results showed that the survival rate was significantly different under the different concentrations of EMS and the different processing time. In the same processing time, the EMS concentrations were increased, but the suspension cells survival rate decreased gradually. The optimum EMS concentration for the mutagenesis was 0.4% and the best processing time was 1 hour.

OBJECTIVE To optimize a simple and effective method for total RNA extraction from bulblet of Fritillaria anhuiensis. METHOD Four methods, i. e. guanidine isothiocyanate, bentonite, modified SDS/phenol and the RNAiso plus, were used to extract total RNA from bulblet of F. anhuiensis. Then the results of the extraction were compared and analyzed by electrophoresis detection and RT-PCR verification. RESULT The total RNA extracted by bentonite method were clear and no dispersion, the integrity of the RNA was well, and there was no obvious contamination with DNA and other impurities, was suitable for RT-PCR test. CONCLUSION The bentonite method is quick, economic, and efficient for total RNA extraction from bulblet of F. anhuiensis.