122 research outputs found
Biochemical changes in low-salt fermentation of solidstate soy sauce
Low-salt solid-state fermentation soy sauce was prepared with defatted soy bean and wheat bran. Biochemical changes during the aging of the soy sauce mash were investigated. Results show that after a 15-day aging period, the contents of total nitrogen, formol titration nitrogen, free amino acids, reducing sugar, total sugar and the brown color were increased. However pH was decreased during the fermentation period. Furthermore contents of free amino acids in low-salt solid-state fermentation soy sauce fluctuated during the fermentation period with most of the free amino acids increased. The analysis of free amino acid composition shows that the contents of glutamic acid, aspartic acid, alanine and leucine were higher than other amino acids. Therefore it means that these amino acids may contribute to the taste and flavor of low-salt solid-state fermentation soy sauce. Analyzing the biochemical change in the fermented process of soy sauce is helpful to find out the shortcoming of lowsalt solid-state fermented soy sauce. It is of benefit in improving the quality of low-salt solid-state fermented soy sauce
uPA is upregulated by high dose celecoxib in women at increased risk of developing breast cancer
<p>Abstract</p> <p>Background</p> <p>While increased urokinase-type plasminogen activator (uPA) expression in breast cancer tissue is directly associated with poor prognosis, recent evidence suggests that uPA overexpression may suppress tumor growth and prolong survival. Celecoxib has been shown to have antiangiogenic and antiproliferative properties. We sought to determine if uPA, PA inhibitor (PAI)-1 and prostaglandin (PG)E<sub>2 </sub>expression in nipple aspirate fluid (NAF) and uPA and PGE<sub>2 </sub>expression in plasma were altered by celecoxib dose and concentration in women at increased breast cancer risk.</p> <p>Methods</p> <p>NAF and plasma samples were collected in women at increased breast cancer risk before and 2 weeks after taking celecoxib 200 or 400 mg twice daily (bid). uPA, PAI-1 and PGE<sub>2 </sub>were measured before and after intervention.</p> <p>Results</p> <p>Celecoxib concentrations trended higher in women taking 400 mg (median 1025.0 ng/mL) compared to 200 mg bid (median 227.3 ng/mL), and in post- (534.6 ng/mL) compared to premenopausal (227.3 ng/mL) women. In postmenopausal women treated with the higher (400 mg bid) celecoxib dose, uPA concentrations increased, while PAI-1 and PGE<sub>2 </sub>decreased. In women taking the higher dose, both PAI-1 (r = -.97, p = .0048) and PGE<sub>2 </sub>(r = -.69, p = .019) in NAF and uPA in plasma (r = .45, p = .023) were correlated with celecoxib concentrations.</p> <p>Conclusion</p> <p>Celecoxib concentrations after treatment correlate inversely with the change in PAI-1 and PGE<sub>2 </sub>in the breast and directly with the change in uPA in the circulation. uPA upregulation, in concert with PAI-1 and PGE<sub>2 </sub>downregulation, may have a cancer preventive effect.</p
Complete Sequencing and Pan-Genomic Analysis of Lactobacillus delbrueckii subsp. bulgaricus Reveal Its Genetic Basis for Industrial Yogurt Production
Lactobacillus delbrueckii subsp. bulgaricus (Lb. bulgaricus) is an important species of Lactic Acid Bacteria (LAB) used for cheese and yogurt fermentation. The genome of Lb. bulgaricus 2038, an industrial strain mainly used for yogurt production, was completely sequenced and compared against the other two ATCC collection strains of the same subspecies. Specific physiological properties of strain 2038, such as lysine biosynthesis, formate production, aspartate-related carbon-skeleton intermediate metabolism, unique EPS synthesis and efficient DNA restriction/modification systems, are all different from those of the collection strains that might benefit the industrial production of yogurt. Other common features shared by Lb. bulgaricus strains, such as efficient protocooperation with Streptococcus thermophilus and lactate production as well as well-equipped stress tolerance mechanisms may account for it being selected originally for yogurt fermentation industry. Multiple lines of evidence suggested that Lb. bulgaricus 2038 was genetically closer to the common ancestor of the subspecies than the other two sequenced collection strains, probably due to a strict industrial maintenance process for strain 2038 that might have halted its genome decay and sustained a gene network suitable for large scale yogurt production
Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples
Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts
Flavor and taste compounds analysis in Chinese solid fermented soy sauce
The analysis of free amino acid and volatile compounds were conducted to understand the changes in taste and flavor of five samples which were solid fermented. The values of bitter, sweet and MSG-like free amino acids in these soy sauces were significantly different. The taste of soy sauce waspredominated by saltiness, followed by moderate “umami” and sweet taste and slight bitterness, likely as a result of the balance and interaction among different taste components. A total of 82 kinds of volatile compounds were identified, including alcohols, acids, esters, aldehydes, ketones, phenols, heterocyclic compounds, alkynes and benzenes. The subtle aroma of the soy sauce seemed to depend not only on particular key compounds but also on a “critical balance” or a “weighted concentrationratio” of volatile compounds
Metagenomic Discovery and Characterization of Multi-Functional and Monomodular Processive Endoglucanases as Biocatalysts
Biomass includes cellulose, hemicelluloses, pectin and lignin; constitutes the components of dietary fibre of plant and alge origins in animals and humans; and can potentially provide inexhaustible basic monomer compounds for developing sustainable biofuels and biomaterials for the world. Development of efficacious cellulases is the key to unlock the biomass polymer and unleash its potential applications in society. Upon reviewing the current literature of cellulase research, two characterized and/or engineered glycosyl hydrolase family-5 (GH5) cellulases have displayed unique properties of processive endoglucanases, including GH5-tCel5A1 that was engineered and was originally identified via targeted genome sequencing of the extremely thermophilic Thermotoga maritima and GH5-p4818Cel5_2A that was screened out of the porcine hindgut microbial metagenomic expression library. Both GH5-tCel5A1 and GH5-p4818Cel5_2A have been characterized as having small molecular weights with an estimated spherical diameter at or < 4.6 nm; being monomodular without a required carbohydrate-binding domain; and acting as processive β-1,4-endoglucanases. These two unique GH5-tCel5A1 and GH5-p4818Cel5_2A processive endocellulases are active in hydrolyzing natural crystalline and pre-treated cellulosic substrates and have multi-functionality towards several hemicelluloses including β-glucans, xylan, xylogulcans, mannans, galactomannans and glucomannans. Therefore, these two multifunctional and monomodular GH5-tCel5A1 and GH5-p4818Cel5_2A endocellulases already have promising structural and functional properties for further optimization and industrial applications
Monomodular and multifunctional processive endocellulases: implications for swine nutrition and gut microbiome
Abstract Poor efficiency of dietary fibre utilization not only limits global pork production profit margin but also adversely affects utilization of various dietary nutrients. Poor efficiency of dietary nutrient utilization further leads to excessive excretion of swine manure nutrients and results in environmental impacts of emission of major greenhouse gases (GHG), odor, nitrate leaching and surface-water eutrophication. Emission of the major GHG from intensive pork production contributes to global warming and deteriorates heat stress to pigs in tropical and sub-tropical swine production. Exogenous fibre enzymes of various microbial cellulases, hemicellulases and pectinases have been well studied and used in swine production as the non-nutritive gut modifier feed enzyme additives in the past over two decades. These research efforts have aimed to improve growth performance, nutrient utilization, intestinal fermentation as well as gut physiology, microbiome and health via complementing the porcine gut symbiotic microbial fibrolytic activities towards dietary fibre degradation. The widely reported exogenous fibre enzymes include the singular use of respective cellulases, hemicellulases and pectinases as well as their multienzyme cocktails. The currently applied exogenous fibre enzymes are largely limited by their inconsistent in vivo efficacy likely due to their less defined enzyme stability and limited biochemical property. More recently characterized monomodular, multifunctional and processive endoglucanases have the potential to be more efficaciously used as the next-generation designer fibre biocatalysts. These newly emerging multifunctional and processive endoglucanases have the potential to unleash dietary fibre sugar constituents as metabolic fuels and prebiotics, to optimize gut microbiome, to maintain gut permeability and to enhance performance in pigs under a challenged environment as well as to parallelly unlock biomass to manufacture biofuels and biomaterials
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