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Microorganisms Oct 2022Broussonetia papyrifera has a high lignocellulose content leading to poor palatability and low digestion rate of ruminants. Thus, dynamic profiles of fermentation...
Broussonetia papyrifera has a high lignocellulose content leading to poor palatability and low digestion rate of ruminants. Thus, dynamic profiles of fermentation lignocellulose characteristics, microbial community structure, potential function, and interspecific relationships of B. papyrifera mixing with wheat bran in different ratios: 100:0 (BP100), 90:10 (BP90), 80:20 (BP80), and 65:35 (BP65) were investigated on ensiling days 5, 15, 30, and 50. The results showed that adding bran increased the degradation rate of hemicellulose, neutral detergent fiber, and the activities of filter paper cellulase, endoglucanase, acid protease, and neutral protease, especially in the ratio of 65:35. Lactobacillus, Pediococcus, and Weissella genus bacteria were the dominant genera in silage fermentation, and Pediococcus and Weissella genus bacteria regulated the process of silage fermentation. Compared with monospecific B. papyrifera silage, adding bran significantly increased the abundance of Weissella sp., and improved bacterial fermentation potential in BP65 (p < 0.05). Distance-based redundancy analysis showed that lactic acid bacteria (LAB) were significantly positive correlated with most lignocellulose content and degrading enzymes activities, while Monascus sp. and Syncephalastrum sp. were opposite (p < 0.05). Co-occurrence network analysis indicated that there were significant differences in microbial networks among different mixing ratios of B. papyrifera silage prepared with bran. There was a more complex, highly diverse and less competitive co-occurrence network in BP65, which was helpful to silage fermentation. In conclusion, B. papyrifera ensiled with bran improved the microbial community structure and the interspecific relationship and reduced the content of lignocellulose.
PubMed: 36296291
DOI: 10.3390/microorganisms10102015 -
Food Science and Biotechnology Nov 2022MV was reported to have beneficial effects in ameliorating insulin resistance in mice, but the intrinsic mechanisms for glucose homeostasis are unclear. This study...
UNLABELLED
MV was reported to have beneficial effects in ameliorating insulin resistance in mice, but the intrinsic mechanisms for glucose homeostasis are unclear. This study examined the anti-diabetic mechanism of MV using HepG2 cells and C57BL/KsJ- mice. MV increased insulin sensitivity by promoting insulin-dependent glucose uptake and activating glycogen accumulation in HepG2 cells. Furthermore, the glucose homeostasis was enhanced in mice administered 1 mg/kg/day of MV for eight weeks by activating the IRS-1/PI3K/Akt and AMPK pathways in the skeletal muscle and liver tissue. In addition, MV promoted glycogen synthesis by regulating the key enzymes, including GSK-3β and GS, and suppressed gluconeogenesis by inhibiting the mRNA expressions of G6pase and PEPCK. These findings show that MV regulates both signaling pathways and improves the glucose metabolism disorder. Thus, MV might be an alternative functional food or nutraceutical in ameliorating T2DM.
SUPPLEMENTARY INFORMATION
The online version contains supplementary material available at 10.1007/s10068-022-01146-4.
PubMed: 36278136
DOI: 10.1007/s10068-022-01146-4 -
Foods (Basel, Switzerland) Sep 2022-fermented red mold rice (RMR) has excellent physiological efficacy on lipid metabolism and liver function. This study investigated the ameliorative effects of...
-fermented red mold rice (RMR) has excellent physiological efficacy on lipid metabolism and liver function. This study investigated the ameliorative effects of monascuspiloin (MP) from RMR on alcoholic liver injury in mice, and further clarified its mechanism of action. Results showed that MP intervention obviously ameliorated lipid metabolism and liver function in mice with over-drinking. In addition, dietary MP intervention reduced liver MDA levels and increased liver CAT, SOD, and GSH levels, thus alleviating liver oxidative stress induced by excessive drinking. 16S rRNA amplicon sequencing showed that MP intervention was beneficial to ameliorate intestinal microbiota dysbiosis by elevating the proportion of norank_f_, , , , , etc., but decreasing the proportion of , norank_f_, _UCG-001, , norank_f_, unclassified_f_, etc. Additionally, correlation network analysis indicated that the key intestinal bacterial taxa intervened by MP were closely related to some biochemical parameters of lipid metabolism, liver function, and oxidative stress. Moreover, liver metabolomics analysis revealed that dietary MP supplementation significantly regulated the levels of 75 metabolites in the liver, which were involved in the synthesis and degradation of ketone bodies, taurine, and hypotaurine metabolism, and other metabolic pathways. Furthermore, dietary MP intervention regulated gene transcription and protein expression associated with hepatic lipid metabolism and oxidative stress. In short, these findings suggest that MP mitigates alcohol-induced liver injury by regulating the intestinal microbiome and liver metabolic pathway, and thus can serve as a functional component to prevent liver disease.
PubMed: 36230124
DOI: 10.3390/foods11193048 -
Journal of Fungi (Basel, Switzerland) Aug 2022In this study, the gene -5162 from LQ-6, identified as chitin synthase gene VI (6), was knocked out to disrupt the chitin biosynthetic pathway and regulate the...
In this study, the gene -5162 from LQ-6, identified as chitin synthase gene VI (6), was knocked out to disrupt the chitin biosynthetic pathway and regulate the biosynthesis of pigments (MPs) and citrinin. The results showed that the aerial hyphae on a solid medium were short and sparse after the deletion of 6 in LQ-6, significantly reducing the germination percentage of active spores to approximately 22%, but the colony diameter was almost unaffected. Additionally, the deletion of 6 changed the mycelial morphology of LQ-6 during submerged fermentation and increased its sensitivity to environmental factors. MP and citrinin biosynthesis was dramatically inhibited in the recombinant strain. Furthermore, comparative transcriptome analysis revealed that the pathways related to spore development and growth, including the MAPK signaling pathway, chitin biosynthetic pathway, and regulatory factors A and A genes, were significantly downregulated in the early phase of fermentation. The mRNA expression levels of genes in the cluster of secondary metabolites were significantly downregulated, especially those related to citrinin biosynthesis. This is the first detailed study to reveal that 6 plays a vital role in regulating the cell growth and secondary metabolism of the genus.
PubMed: 36135635
DOI: 10.3390/jof8090910 -
Frontiers in Microbiology 2022Silage exposed to air is prone to deterioration and production of unpleasant volatile chemicals that can seriously affect livestock intake and health. The aim of this...
Silage exposed to air is prone to deterioration and production of unpleasant volatile chemicals that can seriously affect livestock intake and health. The aim of this study was to investigate the effects of (LP), (LB), and a combination of LP and LB (PB) on the quality, microbial community and volatile chemicals of silage at 0, 4, and 8 days after aerobic exposure. During aerobic exposure, LP had higher WSC and LA contents but had the least aerobic stability, with more harmful microorganisms such as and and produced more volatile chemicals such as Isospathulenol and 2-Furancarbinol. LB slowed down the rise in pH, produced more acetic acid and effectively improved aerobic stability, while the effect of these two additives combined was intermediate between that of each additive alone. Correlation analysis showed that , , , and were associated with aerobic deterioration, and , , , and were associated with volatile chemicals. In conclusion, LB preserved the quality of silage during aerobic exposure, while LP accelerated aerobic deterioration.
PubMed: 36118219
DOI: 10.3389/fmicb.2022.938153 -
Current Research in Food Science 2022As a typical representative of Chinese rice wine (), rice wine is famous for its red color, mellow taste and strong fragrance. However, due to the open brewing...
As a typical representative of Chinese rice wine (), rice wine is famous for its red color, mellow taste and strong fragrance. However, due to the open brewing environment and traditional fermentation technology, there are some safety risks in traditional brewed rice wine, such as a certain amount of biogenic amines. In this study, the dynamic changes and the differences of microbial communities and volatile flavor components between two types of rice wine with high and low biogenic amine contents (LBAW and HBAW) during the traditional brewing were systematically investigated. The results showed that the total biogenic amine contents in LBAW and HBAW were 20.91 and 69.06 mg/L, respectively. The contents of putrescine, cadaverine, spermine and spermidine in HBAW were significantly higher than those in LBAW, and it was noteworthy that spermine content in HBAW was 17.62 mg/L, which was not detected in LBAW. In addition, the volatile flavor characteristics of the two kinds of rice wine were obviously different. The contents of acetophenone, n-butyl butanoate and benzothiazole were obviously higher in HBAW, while the contents of isoamyl acetate, ethyl lactate, ethyl caprate and phenylethyl alcohol were significantly higher in LBAW. High-throughput sequencing of 16S/ITS amplicon revealed that , , , , and were the predominant microbial genera during the traditional brewing of HBAW, while , , , and were the predominant microbial genera during the traditional brewing of LBAW. Correlation analysis revealed that biogenic amines were significantly negatively correlated with unclassified_o_, , , and , but positively correlated with , , and . In addition, we also found that , and were significantly positively correlated with most of the volatile flavor components, while , and were significantly negatively correlated with most of the volatile flavor components. In addition, bioinformatical analysis based on PICRUSt demonstrated that the key enzymes for biogenic amine biosynthesis were more abundant in the microbial community of HBAW than LBAW. These findings demonstrate that the formations of volatile flavor and biogenic amines in rice wine are influenced by microbial community during the fermentation. This work facilitates scientific understanding of the formation mechanism of biogenic amines, and may be useful to develop effective strategies to improve the quality of rice wine.
PubMed: 36110382
DOI: 10.1016/j.crfs.2022.08.020 -
Foods (Basel, Switzerland) Aug 2022As an important medicine homologous food, Chinese jujube is rich in nutrition and medicinal value. To enhance the bioactive compounds level of Chinese jujube products,...
As an important medicine homologous food, Chinese jujube is rich in nutrition and medicinal value. To enhance the bioactive compounds level of Chinese jujube products, three kinds of fungi strains (, and ) were firstly selected to evaluate their effects on total soluble phenolic compounds (TSPC) and total soluble flavonoids compounds (TSFC) contents during liquid state fermentation of Chinese jujube. As the best strain, the highest contents of TSPC and TSFC could increase by 102.1% (26.02 mg GAE/g DW) and 722.8% (18.76 mg RE/g DW) under fermentation when compared to the unfermented sample, respectively. Qualitative and quantitative analysis of individual polyphenol compounds indicated that proto-catechuic acid, -hydroxybenzoic acid and chlorogenic acid showed the highest level in the fer-mented Chinese jujube at the 7th day, which was enhanced by 16.72-, 14.05- and 6.03-fold when compared to the control, respectively. Combining with RNA sequencing, function annotation of CAZymes database and polyphenol profiling, three potential transformation pathways of poly-phenol compounds were proposed in the fermented Chinese jujube by , such as the conversion of insoluble bound phenolic acids, rutin and anthocyanin degradation. These findings would be beneficial for better understanding of the biotransformation mechanism of polyphenol compounds in fungi fermentation.
PubMed: 36076732
DOI: 10.3390/foods11172546 -
Frontiers in Microbiology 2022"Green-covering" (TQ), as one of , is a special fermentative starter (also known as in Chinese) that originated in southern China and is characterized by a layer of...
"Green-covering" (TQ), as one of , is a special fermentative starter (also known as in Chinese) that originated in southern China and is characterized by a layer of green mold covering () the surface and (sometimes) with a red heart. It plays a vital role in producing light-aroma-type (LATB). However, to date, the microbiota that causes red heart of TQ remain largely unexplored, and it is still unclear how these microbiota influence on the quality of LATB. In this study, two types of TQ, one with a red heart (RH) and another with a non-red heart (NRH), were investigated by high throughput sequencing (HTS) and directional screening of culture-dependent methods. The obtained results revealed the differences in the microbial communities of different TQ and led to the isolation of two species of . Interestingly, the results of high performance liquid chromatography (HPLC) detection showed that citrinin was not detected, indicating that isolated from TQ was no safety risk, and the contents of gamma-aminobutyric acid in the fermented grains of RH were higher than that of NRH during the fermentation. Selecting the superior autochthonous (M1) isolated from the TQ to reinoculate into the TQ-making process, established a stable method for producing the experimental "red heart" (ERH), which confirmed that the cause of "red heart" was the growth of strains. After the lab-scale production test, ERH increased ethyl ester production and reduced higher alcohols production. In addition, had an inhibitory effect on the growth of and . This study provides the safe, health-beneficial, and superior fermentation strains and strategies for improving the quality of TQ and LATB.
PubMed: 36060768
DOI: 10.3389/fmicb.2022.973616 -
Frontiers in Microbiology 2022spp. are traditional medicinal and edible filamentous fungi in China, and can produce various secondary metabolites, such as pigments (MPs) and citrinin (CIT). Genetic...
spp. are traditional medicinal and edible filamentous fungi in China, and can produce various secondary metabolites, such as pigments (MPs) and citrinin (CIT). Genetic modification methods, such as gene knock-out, complementation, and overexpression, have been used extensively to investigate the function of related genes in spp.. However, the resistance selection genes that can have been used for genetic modification in spp. are limited, and the gene replacement frequency (GRF) is usually <5%. Therefore, we are committed to construct a highly efficient gene editing system without resistance selection marker gene. In this study, using M7 as the starting strain, we successfully constructed a so-called markerlessly and highly genetic modification system including the mutants ΔΔ and ΔΔ::, in which we used the endogenous gene from M7 instead of the resistance marker gene as the screening marker, and simultaneously deleted related to non-homologous end joining in M7. Then, the morphology, the growth rate, the production of MPs and CIT of the mutants were analyzed. And the results show that the mutant strains have normal mycelia, cleistothecia and conidia on PDA+Uridine(U) plate, the biomass of each mutant is also no different from M7. However, the U addition also has a certain effect on the orange and red pigments yield of M7, which needs our further study. Finally, we applied the system to delete multiple genes from M7 separately or continuously without any resistance marker gene, and found that the average GRF of ΔΔ was about 18 times of that of M7. The markerlessly and highly genetic modification system constructed in current study not only will be used for multi-gene simultaneous modification in spp., and also lays a foundation for investigating the effects of multi-genes modification on spp..
PubMed: 35979480
DOI: 10.3389/fmicb.2022.952323 -
Frontiers in Microbiology 2022The biosynthesis of penicillin G (PG) is compartmentalized, and the transportation of the end and intermediate products, and substrates (precursors) such as L-cysteine...
The biosynthesis of penicillin G (PG) is compartmentalized, and the transportation of the end and intermediate products, and substrates (precursors) such as L-cysteine (L-Cys), L-valine (L-Val) and phenylacetic acid (PAA) requires traversing membrane barriers. However, the transportation system of PAA as a side chain of PG are unclear yet. To discover ABC transporters (ABCTs) involved in the transportation of PAA, the expression levels of 38 ABCT genes in the genome of M7, culturing with and without PAA, were examined, and found that one gene, namely 31, was considerably up-regulated with PAA, indicating that 31 may be relative with PAA transportation. Furthermore the disruption of 31 was carried out, and the effects of two PG substrate's amino acids (L-Cys and L-Val), PAA and some other weak acids on the morphologies and production of secondary metabolites (SMs) of Δ31 and M7, were performed through feeding experiments. The results revealed that L-Cys, L-Val and PAA substantially impacted the morphologies and SMs production of Δ31 and M7. The UPLC-MS/MS analysis findings demonstrated that Δ31 did not interrupt the synthesis of PG in M7. According to the results, it suggests that 31 is involved in the resistance and detoxification of the weak acids, including the PAA in M7.
PubMed: 35966689
DOI: 10.3389/fmicb.2022.915721