Consolidated bioprocessing technology can be used for Kluyveromyces marxianus YX01 to produce ethanol from Jerusalem artichoke, which is one of the potential processes to produce biofuel from non-cereal crops. In this study, we combined the aeration rate with the substrate concentration to conduct cross-over experiments for K. marxinaus YX01, and studied ethanol fermentation and the influence of inulin enzyme activity. The substrate concentration had a little repressive effect on ethanol productivity. When substrate concentration reached 250 g/L under anaerobic conditions, ethanol concentration was 84.8 g/L, and ethanol yield was reduced from 86.4% (50 g/L substrate concentration) to 84.7% of the theoretical value. Aeration rate could accelerate K. marxinaus YX01 ethanol fermentation, but reduced ethanol yield. When substrate concentration reached 250 g/L under aeration at 1.0 vvm, ethanol yield was reduced from 84.7% under anaerobic conditions to 73.3% of the theoretical value. With increased concentration of the carbon source and reduced aeration rate, the inulinase of K. marxinaus YX01 reduced and the concentration of glycerol increased, however, the acetic acid increased with the increased concentration of the carbon source and aeration rate. When substrate concentration reached 250 g/L under anaerobic conditions, inulinase activity was only 6.59 U/mL; when substrate concentration reached 50 g/L under aeration at 1.0 vvm, inulinase activity was 21.54 U/mL.
Ethanol ; metabolism ; Fermentation ; Glycoside Hydrolases ; metabolism ; Helianthus ; metabolism ; Inulin ; metabolism ; Kluyveromyces ; classification ; metabolism ; Substrate Specificity

Race and ethnicity are influential in estimating glomerular filtration rate (GFR). We aimed to find the Korean coefficients for the Modification of Diet in Renal Disease (MDRD) study equations and to obtain novel proper estimation equations. Reference GFR was measured by systemic inulin clearance. Serum creatinine (SCr) values were measured by the alkaline picrate Jaffe kinetic method, then, recalibrated to CX3 analyzer and to isotope dilution mass spectrometry (IDMS). The Korean coefficients for the 4 and 6 variable MDRD and IDMS MDRD study equations based on the SCr recalibrated to CX3 and to IDMS were 0.73989/0.74254 and 0.99096/0.9554, respectively. Coefficients for the 4 and 6 variable MDRD equations based on the SCr measured by Jaffe method were 1.09825 and 1.04334, respectively. The modified equations showed better performances than the original equations. The novel 4 variable equations for Korean based on the SCr measured and recalibrated to IDMS were 107.904xSCr-1.009xage-0.02 (x0.667, if woman) and 87.832xSCr-0.882xage0.01 (x0.653, if woman), respectively. Modified estimations of the MDRD and IDMS MDRD study equations with ethnic coefficients and the novel equations improve the performance of GFR estimation for the overall renal function.
Adult ; Aged ; Aged, 80 and over ; Algorithms ; Creatinine/blood ; *Diet ; Female ; *Glomerular Filtration Rate ; Humans ; Inulin/metabolism ; Kidney Diseases/*ethnology/physiopathology ; Male ; Mass Spectrometry ; Middle Aged ; Republic of Korea/ethnology

Inulin has been used as a prebiotic to alleviate glucose and lipid metabolism disorders in mice and humans by modulating the gut microbiota. However, the mechanism underlying the alleviation of metabolic disorders by inulin through interactions between the gut microbiota and host cells is unclear. We use ob/ob mice as a model to study the effect of inulin on the cecal microbiota by 16S rRNA gene amplicon sequencing and its interaction with host cells by transcriptomics. The inulin-supplemented diet improved glucose and lipid metabolism disorder parameters in ob/ob mice, alleviating fat accumulation and glucose intolerance. The α diversity of gut microbial community of ob/ob mice was reduced after inulin treatment, while the β diversity tended to return to the level of wild type mice. Interestingly, Prevotellaceae UCG 001 (family Prevotellaceae) was obviously enriched after inulin treatment. A comparative analysis of the gene expression profile showed that the cecal transcriptome was changed in leptin gene deficiency mice, whereas the inulin-supplemented diet partially reversed the changes in leptin gene-related signaling pathways, especially AMPK signaling pathway, where the levels of gene expression became comparable to those in wild type mice. Further analysis indicated that Prevotellaceae UCG 001 was positively correlated with the AMPK signaling pathway, which was negatively correlated with markers of glycolipid metabolism disorders. Our results suggest that the inulin-supplemented diet alleviates glucose and lipid metabolism disorders by partially restoring leptin related pathways mediated by gut microbiota.
AMP-Activated Protein Kinases ; metabolism ; Animals ; Cecum ; enzymology ; metabolism ; microbiology ; Gastrointestinal Microbiome ; drug effects ; Inulin ; therapeutic use ; Leptin ; genetics ; Male ; Metabolic Diseases ; drug therapy ; enzymology ; metabolism ; microbiology ; Mice ; Mice, Obese ; Prebiotics ; Signal Transduction ; drug effects ; Transcriptome

Prebiotics modulate microbial composition and ensure a healthy gastrointestinal tract environment that can prevent colon cancer development. These natural dietary compounds are therefore potential chemopreventive agents. Thirty Sprague-Dawley rats (4 months old) were experimentally treated with procarcinogen dimethylhydrazine to induce colon cancer development. The rats were randomly assigned to three groups: a control group (CG), a group treated with dimethylhydrazine (DMH), and a group given DMH and inulin, a prebiotic (DMH+PRE). The effects of inulin on the activities of bacterial glycolytic enzymes, short-chain fatty acids, coliform and lactobacilli counts, cytokine levels, and cyclooxygenase-2 (COX-2) and transcription nuclear factor kappa beta (NFkappaB) immunoreactivity were measured. Inulin significantly decreased coliform counts (p < 0.01), increased lactobacilli counts (p < 0.001), and decreased the activity of beta-glucuronidase (p < 0.01). Butyric and propionic concentrations were decreased in the DMH group. Inulin increased its concentration that had been reduced by DMH. Inulin decreased the numbers of COX-2- and NFkappaB-positive cells in the tunica mucosae and tela submucosae of the colon. The expression of IL-2, TNFalpha, and IL-10 was also diminished. This 28-week study showed that dietary intake of inulin prevents preneoplastic changes and inflammation that promote colon cancer development.
Animals ; Bacterial Proteins/genetics/metabolism ; Colon/enzymology ; Colonic Neoplasms/chemically induced/*drug therapy/metabolism ; Colony Count, Microbial ; Cyclooxygenase 2/genetics/metabolism ; Cytokines/blood/genetics ; Diet ; Dietary Supplements/analysis ; Dimethylhydrazines/toxicity ; Enterobacteriaceae/drug effects/physiology ; Fatty Acids, Volatile/genetics/metabolism ; Female ; Gene Expression Regulation/drug effects ; Inulin/administration & dosage/*metabolism ; Lactobacillaceae/drug effects/physiology ; Male ; NF-kappa B/genetics/metabolism ; Prebiotics/*analysis ; Rats ; Rats, Sprague-Dawley