Mixture Of Glucose Research Articles

Pharmacological effect of Heritiera fomes on Long Evans rats against Postprandial Hyperglycemia and adsorption in vitro.

Natural restoratives from traditional medicinal plants are considered to be a convenient, potent, and risk-free substitute treatment for hyperglycaemia. Our objective was to explore the activity of the crude extract of Heritiera fomes on postprandial hyperglycaemia by assessing relative measurements in a laboratory animal model. The Streptozotocin induced diabetic rat (n = 88, twenty-two per group) was used for the glucose tolerance test as an initial support for the study. BaSO4was administered orally as a marker to measure gut motility after one hour of methanolic extract (500mg/kg body weight) administration where, only purified water (10 ml/kg) was used to treat the control group (n = 12) and a dose (500mg/kg) of H. fomes extract was used for the test group (n = 12 in each group). After 60min of incubation of the mixture of extract and glucose with 10% (v/v) yeast cell suspension, the absorbance was measured to determine the capacity of glucose absorption by yeast cells. Sixty Long Evans rats (n = 12 in each group) were used to assess disaccharidase enzyme activity as µmol/mg protein per hour by Lowry's protein estimation method. The carbohydrate absorption investigation was executed to evaluate the leftover sucrose content in the gastrointestinal system (n = 64). After oral administration of MHFL (71.84%), MHFB (71.41%), and MHFR (72.55%), GI motility (%) increased significantly (p < 0.001) compared to the control group (59.06%). A significant increase in glucose uptake and adsorption capacity measured by different concentrations of glucose ensures the decrease of glucose bound rate and a significant drop in blood glucose concentration. The significant (p < 0.001) decrease in intestinal disaccharidase activity of MHFL (1.40), MHFB (1.36), and MHFR (1.20) in comparison to the control group (1.50) indicates that the presence of H. fomes may reduce glucose absorption in the small bowel. Significant (p < 0.001 & p < 0.05) accumulation of sucrose content in the six different parts of the GI tract suggests the absorption of sucrose was decreased. The findings of this study provide evidence on probable mechanisms for the anti-diabetic characteristics of H. fomes, and it is predicted that this plant will be studied further for the development of strong anti-hyperglycemic medicines.

Techno-Economic Analysis of Extractive Butanol Fermentation by Immobilized Cells with Large Extractant Volume

There are several challenges for ABE fermentation to be used in an industrial scale including the low of butanol yield, the high energy requirement for separation and purification, and the competeness of sugar with food demand as substrat. In this study, techno-economical aspects of ABE fermentation by using immobilized cells with large extractant volume were studied. Overall production process was designed using rice straw as raw material which is semi-hydrolyzed to produce cellobiose, glucose, xylose, and arabinose mixture. Concentrated sugar was then fed to extractive fed-batch fermentation using immobilized cells. Finally, extractant was recovered and products were purified by distillation column. By evaluating this process design for the small scale capacity of 238 kg-butanol and acetone/day, the energy requirement was 41.3 MJ/kg-butanol and acetone and the cost was 1.91 $/kg-butanol and acetone. Although the cost was higher than butanol produced by petrochemical process of 1.08 $/kg-butanol, it may reduce if the scale is increased.

Biochemical Study on the Kinetic Properties of the Invertase Produced by Saccharomyces Cerevisiae

Invertases are enzymes that hydrolyze sucrose to produce an equimolar mixture of glucose and fructose, which is of interest for various industrial applications. The present study aimed to produce invertase by Saccharomyces cerevisiae isolated from Baker’s yeast and grape samples using the standardize technique. The enzyme activity was characterized with some parameters like pH, temperature, metal ions, kinetic parameters and inhibitors (fructose, glucose and copper (II) sulfate). Spectrophotometric methods were used to study enzyme kinetics and to determine the factors affecting enzyme activity. The optimum activity was recorded at 55˚C for both invertases. The optimum activity was at pH 6.0 for Baker’s yeast invertase and at pH 10 for grape invertase. From Lineweaver-Burk Plot, Vmax was found to be 24.39 ± 2.44 nmol/min/mg protein and the Km approximately 0.860 ± 0.04 mM for Baker's yeast invertase but in case of grape invertase, Vmax was 23.25 ± 3.14 nmol/min/mg protein and the Km approximately1.243 ± 0.07 mM. Enzyme activity was increased in the presence of 5 mM Ca+2 ions for Baker’s yeast, whereas showed the maximum activity at 5 mM Mg+2 ions in case of grape fruit invertase. Using sucrose as substrate, the Kcat, Kcat/Km and Ks values were 0.28 ± 0.02 min-1, 0.325 ± 0.03 mM-1 min-1 and 27.03 ± 5.24 ml/min/mg protein for Baker’s yeast invertase activity, whereas were 0.56 ± 0.008 min-1, 0.045 ± 0.003 mM-1 min-1 and 24.39 ± 7.11 ml/min/mg protein for grape invertase values. In conclusion, the S. cerevisiae isolated from grape fruits was more potent for invertase production in comparable with that isolated from Baker’s yeast.

Development of efficient 5-ketogluconate production system by Gluconobacter japonicus.

5-Ketogluconate (5KGA) is a precursor for synthesizing tartrate, a valuable compound used in several industries. In a previous study, Gluconobacter japonicus NBRC 3271 mutant strain D2, which lacks two membranous gluconate 2-dehydrogenases, was shown to produce 5KGA but not 2-ketogluconate from a mixture of glucose and gluconate. In this study, we aimed to develop an efficient 5KGA production system using G. japonicus D2 as the parental strain. D2 produced 5KGA from glucose in a jar fermentor culture; however, 5KGA levels were reduced during the late phase of cultivation. To increase the potential of D2 for 5KGA production, the cytoplasmic metabolism related to the utilization of 5KGA and gluconate was modified; the gno and gntK genes encoding 5KGA reductase and gluconokinase, respectively, were deleted from D2, generating D4. Improved 5KGA production was observed in D4 compared to that in D2, but a significant amount of gluconate remained at the end of cultivation, leading to an unsatisfied yield of 0.83mol (mol glucose)-1. The conversion of gluconate to 5KGA is catalyzed by pyrroloquinoline quinone (PQQ)-dependent glycerol dehydrogenase (GLDH), which easily forms an apoenzyme by releasing PQQ and calcium ions. Thus, the effects of CaCl2 addition to the culture medium on 5KGA production by D4 were investigated. We demonstrated that 1mM CaCl2 addition positively affected the maintenance of the PQQ-GLDH activity toward gluconate and consequently enhanced 5KGA production, and the yield reached 0.97mol (mol glucose)-1. KEY POINTS: • An efficient 5KGA production system was developed with Gluconobacter japonicus. • Deleting the gno and gntK genes blocked the catabolism of 5KGA and gluconate. • The addition of 1mM CaCl2 efficiently improved the conversion of glucose to 5KGA.

Indoor metals pollution and metabolic outcomes among Italian children

Abstract Background Through this study, we aimed to test the association between the exposure to metals measured in indoor dust and metabolic outcomes among children living in areas with environmental exposure to metals. Methods The project “Health impacts of environmental exposure to airborne pollutants in the sites of Brescia and Taranto, Italy: increase knowledge to address preventive intervention of local and global relevance” (ISEIA) enrolled 130 children aged 6 to 13 years (51.5% females) resident from pregnancy in highly industrialized areas of the Brescia province, Northern Italy. Metabolic outcomes including BMI, fasting blood glucose and blood creatinine were measured. The concentration of a mixture of 10 metals in indoor dust was determined through an X-ray fluorescence portable analyzer (p-XRF). Linear regressions and Weighted Quantile Sum (WQS) regression were applied to test for the association between metal exposure and metabolic outcomes. All models were adjusted for age, gender, socio-economic status and area of residence. Results A significant association was observed between Cd and blood creatinine (β = 0.01; 95%CI=0.001, 0.02; p-value=0.028) when considering each individual metal separately in the model. WQS regression showed a positive significant association between the mixture of metals and fasting glucose (β = 0.87; 95%CI 0.14, 1.61; p-value=0.023) identifying Mn, Cr and Cu as the elements with the higher weights, while a marginally significant association was found between the metal mixture and blood creatinine (β = 0.01; 95%CI=-0.001, 0.02; p-value=0.075) where Cd and Ti showed the highest weight. Conclusions We assessed the potential association between exposure to metals in indoor household dust and blood glucose and creatinine. Our results contribute to clarifying the role of metal exposure in the burden of non-communicable diseases although further studies are needed to better understand the relationship between metal exposure and metabolism. Key messages • The metal mixture in indoor household dust is associated with an increase in fasting glucose. • Cd concentration in indoor household dust is associated with an increase in blood creatinine.

Improving 3-hydroxypropionic acid production in E. coli by in silico prediction of new metabolic targets

3-Hydroxypropionic acid (3-HP) production from renewable feedstocks is of great interest in efforts to develop greener processes for obtaining this chemical platform. Here we report an engineered E. coli strain for 3-HP production through the β-alanine pathway. To obtain a new strain capable of producing 3-HP, the pathway was established by overexpressing the enzymes pyruvate aminotransferase, 3-hydroxyacid dehydrogenase, and L-aspartate-1-decarboxylase. Further increase of the 3-HP titer was achieved using evolutionary optimizations of a genome-scale metabolic model of E. coli containing the adopted pathway. From these optimizations, three non-intuitive targets for in vivo assessment were identified: L-alanine aminotransferase and alanine racemase overexpression, and L-valine transaminase knock-out. The implementation of these targets in the production strain resulted in a 40% increase in 3-HP titer. The strain was further engineered to overexpress phosphoenolpyruvate carboxylase, reaching 0.79 ± 0.02 g/L of 3-HP when grown using glucose. Surprisingly, this strain produced 63% more of the desired product when grown using a mixture of glucose and xylose (1:1, C-mol), and gene expression analysis showed that the cellular adjustment to consume xylose had a positive impact on 3-HP accumulation. Fed-batch culture with xylose feeding led to a final titer of 29.1 g/L. These results reinforce the value of computational methods in strain engineering, enabling the design of more efficient strategies to be assessed. Moreover, higher production of 3-HP under a sugar mixture condition points towards the development of bioprocesses based on renewable resources, such as hemicellulose hydrolysates.

The Physiological Functions of AbrB on Sporulation, Biofilm Formation and Carbon Source Utilization in Clostridium tyrobutyricum.

As a pleiotropic regulator, Antibiotic resistant protein B (AbrB) was reported to play important roles in various cellular processes in Bacilli and some Clostridia strains. In Clostridium tyrobutyricum, abrB (CTK_C 00640) was identified to encode AbrB by amino acid sequence alignment and functional domain prediction. The results of abrB deletion or overexpression in C. tyrobutyricum showed that AbrB not only exhibited the reported characteristics such as the negative regulation on sporulation, positive effects on biofilm formation and stress resistance but also exhibited new functions, especially the negative regulation of carbon metabolism. AbrB knockout strain (Ct/ΔabrB) could alleviate glucose-mediated carbon catabolite repression (CCR) and enhance the utilization of xylose compared with the parental strain, resulting in a higher butyrate titer (14.79 g/L vs. 7.91 g/L) and xylose utilization rate (0.19 g/L·h vs. 0.02 g/L·h) from the glucose and xylose mixture. This study confirmed the pleiotropic regulatory function of AbrB in C. tyrobutyricum, suggesting that Ct/ΔabrB was the potential candidate for butyrate production from abundant, renewable lignocellulosic biomass mainly composed of glucose and xylose.

∆nFGF1 Protects β-Cells against High Glucose-Induced Apoptosis via the AMPK/SIRT1/PGC-1α Axis.

Long-term exposure to high glucose leads to β-cell dysfunction and death. Fibroblast growth factor 1 (FGF1) has emerged as a promising diabetes treatment, but its pharmaceutical role and mechanism against glucolipotoxicity-induced β-cell dysfunction remain uncharacterized. Wild-type FGF1 (FGF1WT) may exhibit in vivo mitogenicity, but deletion of N-terminal residues 1-27 gives a nonmitogenic variant, ∆nFGF1, that does not promote cell proliferation and still retains the metabolic activity of FGF1WT. To investigate the roles of ∆nFGF1 on glucose regulation and potential islet β-cell dysfunction, db/db mice were used as a model of type 2 diabetes. The results showed that insulin secretion and apoptosis of islet β-cells were dramatically improved in ∆nFGF1-treated db/db mice. To further test the effects of ∆nFGF1 treatment, pancreatic β-cell (MIN6) cells were exposed to a mixture of palmitic acid (PA) and high glucose (HG) to mimic glucolipotoxic conditions in vitro. Treatment with ∆nFGF1 significantly inhibited glucolipotoxicity-induced apoptosis. Mechanistically, ∆nFGF1 exerts a protective effect on β-cells via activation of the AMPK/SIRT1/PGC-1α signaling pathway. These findings demonstrate that ∆nFGF1 protects pancreatic β-cells against glucolipotoxicity-induced dysfunction and apoptosis.

An easy-to-synthesize porous Mo2C@C nanoparticles substitute part of Pt as electrocatalysts for hydrogen evolution reaction

• Porous Mo 2 C@C nanoparticles are designed and synthesized. • The optimized Mo 2 C@C-Pt/C composite delivers excellent HER electrocatalytic performance. • Effects of Pt/C addition on electrocatalytic performance of Mo 2 C@C are discussed. Developing highly-efficient, low-cost and stable hydrogen evolution reaction (HER) electrocatalyst plays an important role in the strategy to develop hydrogen energy. Herein, molybdenum carbide nanoparticles embedded in porous carbon were facilely synthesized by calcining the mixture of ammonium molybdate, melamine and glucose. When mixed in proportion with commercial Pt/C, the optimized sample exhibits outstanding electrocatalytic activity with low overpotential, small Tafel slope and excellent stability for HER in acidic media.

Resistive Switching in Biocompatible Glucose Films Doped With Honey for Highly Flexible Nonvolatile Memory Application

A mixture of honey and glucose (GH) as a new natural biomaterial for resistive random access memory (RRAM) switching layer on polyethylene terephthalate (PET) substrate is presented. The flexible substrate allows the devices to be bent and used for a wider range of applications. These devices with the GH film exhibit good reproducibility and reliability over more than 300 cycles. Moreover, the ON/OFF ratio of these devices is over 105, and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\mathrm {SET}}$ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\mathrm {RESET}}$ </tex-math></inline-formula> are lower than that of the device with a pure glucose film. The nonvolatile nature of the devices is confirmed by measuring retention for 104 s. This switching behavior is attributed to ohmic conduction and trap-controlled space charge-limited current (TC-SCLC) mechanisms that confirm filament formation and breakage at high-resistance state (HRS) and low-resistance state (LRS), respectively.

Formation and characterization of H2-producing granule in a pilot-scale dynamic membrane bioreactor

This study aimed to achieve high-rate continuous biohydrogen production in a pilot-scale dynamic membrane bioreactor (DMBR), continuously fed with a 20 g/L mixture of glucose, xylose, and arabinose at flow rates ranging from 40 to 160 L/d. The highest average hydrogen production (HP), hydrogen production rate (HPR), and hydrogen yield (HY) were 570 ± 17 L H2/d, 28.52 ± 0.85 L H2/L-d, and 1.48 ± 0.03 mol H2/mol hexose equivalentconsumed, respectively. The high-rate performance was achieved along with the formation of H2-producing granules after 29 days of the continuous operation. The low-cost polyester mesh in DMBR properly acted as a carrier for granule formation. Granulation increased the retention of bacterial concentrations (g VSS) more than twice, which contributed to the high volumetric HPR. It also increased the HY due to the shift of the metabolic flux distribution from lactic acid production and homoacetogenesis to H2-producing butyric and acetic pathways. H2-producing granules exhibited an average size of 1215 μm, settling velocity of 25.8 to 77.0 m/h, porosity of 0.67 to 0.93, and fluid collection efficiency of 0 to 0.29. Extracellular polymeric substances (EPS) secreted by hydrogen-producing bacteria partially covered the pores of the granules, but the substrate transfer was not severely retarded due to the high porosity over 0.7. Clostridium pasteurianum dominated the microbial population in the granules, similar to the microbial population of the biofilm. This study demonstrates the feasibility of high-rate biohydrogen production via the formation of H2-producing granule in pilot-scale.

High-level de novo biosynthesis of cordycepin by systems metabolic engineering in Yarrowia lipolytica

Cordycepin is a nucleoside antibiotic with various biological activities, which has wide applications in the area of cosmetic and medicine industries. However, the current production of cordycepin is costly and time-consuming. To construct the promising cell factory for high-level cordycepin production, firstly, the design and construction of cordycepin biosynthetic pathway were performed in Yarrowia lipolytica. Secondly, the adaptivity between cordycepin biosynthetic pathway and Y. lipolytica was enhanced by enzyme fusion and integration site engineering. Then, the production of cordycepin was improved by the enhancement of adenosine supply. Furthermore, through modular engineering, the production of cordycepin was achieved at 3588.59 mg/L from glucose. Finally, 3249.58 mg/L cordycepin with a yield of 76.46 mg/g total sugar was produced by the engineered strain from the mixtures of glucose and molasses. This research is the first report on the de novo high-level production of cordycepin in the engineered Y. lipolytica.

Co-60 gamma irradiation induced ovalbumin-glucose glycation and allergenicity reduction revealed by high-resolution mass spectrometry and ELISA assay

Ovalbumin (OVA)-glucose mixture was treated with Co-60 irradiation at 0–25 kGy, and effects of irradiation on the glycation and allergenicity of OVA were investigated. Irradiation induced glycation between OVA and glucose, reflected in the significant increase of glycation sites from 3 to 14. Interestingly, OVA irradiated at 25 kGy had three new glycated peptides (568.782+, 739.382+ and 509.752+). The degree of substitution per peptide molecule (DSP) of glycated peptides exhibited different trends with increasing irradiation dose. Particularly, glycated peptides 17–26, 55–60, 263–267 and 368–375 showed markedly decreased DSP values after irradiation at 20 and 25 kGy, which could be caused by the generation of Maillard reaction products (MRPs). MS/MS spectra suggested that neutral loss occurred in glycated arginine, whose structure was similar to MRPs. The IgG- and IgE-binding abilities of OVA significantly decreased with increasing irradiation dose, indicating that the protein allergenicity was reduced.

Effects of organic carbon sources on growth and oil accumulation by Desmodesmus subspicatus LC172266 under mixotrophic condition.

Energy crisis and environmental sustainability have attracted global attention to microalgal biofuels. The present study investigated the impact of organic carbon sources on growth and bio-oil accumulation by an oleaginous microalga Desmodesmus subspicatus LC172266 under mixotrophic culture condition. Glucose and glycerol supported higher growth rates and lipid productivities than sucrose, fructose, mannitol and acetate. Each of the organic carbon source tested supported significantly (P < 0.05) higher growth rates and lipid productivities than the photoautotrophic culture (without organic carbon source). The lipid productivity obtained with a mixture of optima concentrations of glucose and glycerol (5.0gL-1 glycerol + 10.0gL-1glucose) (0.14875 ± 0.002g/L/day) was about 25% and 66% higher than the values obtained with only 10.0gL-1glucose and 5.0gL-1glycerol, respectively. When a batch culture with 5gL-1glycerol was fed with 0.5gL-1glucose daily the cell growth and lipid productivity were lower than the values obtained in a batch culture with a mixture of glucose and glycerol. The lipid productivity obtained in a 4-L photobioreactor was 94% (0.217gL-1day-1), higher than the value obtained in a flask culture with 10.0g/Lglucose (0.112gL-1day-1) and 46% higher than the value obtained in a flask culture with 5.0gL-1glycerol (0.086gL-1day-1).

Production of free fatty acids from various carbon sources by Ogataea polymorpha

Energy shortage and environmental concern urgently require establishing the feasible bio-refinery process from various feedstocks. The methylotrophic yeast Ogataea polymorpha is thermo-tolerant and can utilize various carbon sources, such as glucose, xylose and methanol, which makes it a promising host for bio-manufacturing. Here, we explored the capacity of O. polymorpha for overproduction of free fatty acids (FFAs) from multiple substrates. The engineered yeast produced 674 mg/L FFA from 20 g/L glucose in shake flask and could sequentially utilize the mixture of glucose and xylose. However, the FFA producing strain failed to survive in sole methanol and supplementing co-substrate xylose promoted methanol metabolism. A synergistic utilization of xylose and methanol was observed in the FFA producing strain. Finally, a mixture of glucose, xylose and methanol was evaluated for FFA production (1.2 g/L). This study showed that O. polymorpha is an ideal host for chemical production from various carbon sources.Graphical

Endocrine and Metabolic Impact of Oral Ingestion of a Carob-Pod-Derived Natural-Syrup-Containing D-Pinitol: Potential Use as a Novel Sweetener in Diabetes.

The widespread use of added sugars or non-nutritive sweeteners in processed foods is a challenge for addressing the therapeutics of obesity and diabetes. Both types of sweeteners generate health problems, and both are being blamed for multiple complications associated with these prevalent diseases. As an example, fructose is proven to contribute to obesity and liver steatosis, while non-nutritive sweeteners generate gut dysbiosis that complicates the metabolic control exerted by the liver. The present work explores an alternative approach for sweetening through the use of a simple carob-pod-derived syrup. This sweetener consists of a balanced mixture of fructose (47%) and glucose (45%), as sweetening sugars, and a functional natural ingredient (D-Pinitol) at a concentration (3%) capable of producing active metabolic effects. The administration of this syrup to healthy volunteers (50 g of total carbohydrates) resulted in less persistent glucose excursions, a lower insulin response to the hyperglycemia produced by its ingestion, and an enhanced glucagon/insulin ratio, compared to that observed after the ingestion of 50 g of glucose. Daily administration of the syrup to Wistar rats for 10 days lowered fat depots in the liver, reduced liver glycogen, promoted fat oxidation, and was devoid of toxic effects. In addition, this repeated administration of the syrup improved glucose handling after a glucose (2 g/kg) load. Overall, this alternative functional sweetener retains the natural palatability of a glucose/fructose syrup while displaying beneficial metabolic effects that might serve to protect against the progression towards complicated obesity, especially the development of liver steatosis.

Separation by Size Exclusion: Selective Liquid-Phase Adsorption of l-Lysine from Lysine–Glucose Mixtures on Zeolites

l-Lysine is an essential amino acid of great importance for the pharmaceutical and nutrition industries and is mainly produced by the fermentative conversion of d-glucose. The technological bottleneck for an efficient process is often the development of separation and purification technologies as they can account for 20–50% of the overall operation costs. Liquid-phase adsorption on zeolites is an energy-, resource-, and cost-saving alternative. Zeolites are a well-established and widely available class of adsorbents. In this research, a variety of commercial zeolites of different framework types with varying Si/Al ratios were used to investigate the adsorption of l-lysine from single-component solutions and lysine–glucose mixtures. l-Lysine recovery resulted in adsorption capacities of up to 169 mg g–1 on Hβ-30 in batch experiments. Zeolites showed high l-lysine selectivity in competitive adsorptions from lysine–glucose mixtures, outperforming previously reported adsorbents. Based on the analysis of adsorbent and adsorbate dimensions, a size-exclusion-based separation of l-lysine from d-glucose was proposed, which was found to be primarily responsible for the high l-lysine selectivity. Fourier transform infrared spectroscopy analysis allowed proposing a structure–adsorption relationship for l-lysine on zeolites. The transferability of the batch results to a continuous process was shown. In addition, a high desorption efficiency of up to 90% using water as the desorption solution could be achieved, complemented by successful recyclability tests over five consecutive adsorption–desorption cycles.

Fermentation performance of a Mexican native Clavispora lusitaniae strain for xylitol and ethanol production from xylose, glucose and cellobiose

Lignocellulose hydrolysates are rich in fermentable sugars such as xylose, cellobiose and glucose, with high potential in the biotechnology industry to obtain bioproducts of higher economic value. Thus, it is important to search for and study new yeast strains that co-consume these sugars to achieve better yields and productivity in the processes. The yeast Clavispora lusitaniae CDBB-L-2031, a native strain isolated from mezcal must, was studied under various culture conditions to potentially produce ethanol and xylitol due to its ability to assimilate xylose, cellobiose and glucose. This yeast produced ethanol under microaerobic conditions with yields of 0.451 gethanol/gglucose and 0.344 gethanol/gcellobiose, when grown on 1% glucose or cellobiose, respectively. In mixtures (0.5% each) of glucose:xylose and glucose:xylose:cellobiose the yields were 0.367 gethanol/gGX and 0. 380 gethanol/gGXC, respectively. Likewise, in identical conditions, C. lusitaniae produced xylitol from xylose with a yield of 0.421 gxylitol/gxylose. In 5% glucose or xylose, this yeast had better ethanol and xylitol titers and yields, respectively. However, glucose negatively affected xylitol production in the mixture of both sugars (3% each), producing only ethanol. Xylose reductase (XR) and xylitol dehydrogenase (XDH) activities were evaluated in cultures growing on xylose or glucose, obtaining the highest values in cultures on xylose at 8 h (25.9 and 6.22 mU/mg, respectively). While in glucose cultures, XR and XDH activities were detected once this substrate was consumed (4.06 and 3.32 mU/mg, respectively). Finally, the XYL1 and XYL2 genes encoding xylose reductase and xylitol dehydrogenase, respectively, were up-regulated by xylose, whereas glucose down-regulated their expression.

Liver Transcriptome and Gut Microbiome Analysis Reveals the Effects of High Fructose Corn Syrup in Mice.

High fructose corn syrup (HFCS) is a viscous mixture of glucose and fructose that is used primarily as a food additive. This article explored the effect of HFCS on lipid metabolism-expressed genes and the mouse gut microbiome. In total, ten 3-week-old male C57BL/6J mice were randomly divided into two groups, including the control group, given purified water (Group C) and 30% HFCS in water (Group H) for 16 weeks. Liver and colonic content were collected for transcriptome sequencing and 16S rRNA gene sequencing, respectively. HFCS significantly increased body weight, epididymal, perirenal fat weight in mice (p < 0.05), and the proportion of lipid droplets in liver tissue. The expression of the ELOVL fatty acid elongase 3 (Elovl3) gene was reduced, while Stearoyl-Coenzyme A desaturase 1 (Scd1), peroxisome proliferator activated receptor gamma (Pparg), fatty acid desaturase 2 (Fads2), acyl-CoA thioesterase 2 (Acot2), acyl-CoA thioesterase 2 (Acot3), acyl-CoA thioesterase 4 (Acot4), and fatty acid binding protein 2 (Fabp2) was increased in Group H. Compared with Group C, the abundance of Firmicutes was decreased in Group H, while the abundance of Bacteroidetes was increased, and the ratio of Firmicutes/Bacteroidetes was obviously decreased. At the genus level, the relative abundance of Bifidobacterium, Lactobacillus, Faecalibaculum, Erysipelatoclostridium, and Parasutterella was increased in Group H, whereas that of Staphylococcus, Peptococcus, Parabacteroides, Donghicola, and Turicibacter was reduced in Group H. Pparg, Acot2, Acot3, and Scd1 were positively correlated with Erysipelatoclostridium and negatively correlated with Parabacteroides, Staphylococcus, and Turicibacter. Bifidobacterium was negatively correlated with Elovl3. Overall, HFCS affects body lipid metabolism by affecting the expression of lipid metabolism genes in the liver through the gut microbiome.

Activation of galactose utilization by the addition of glucose for the fermentation of agar hydrolysate using Lactobacillus brevis ATCC 14869.

To investigate the application of carbon catabolite repression (CCR) relaxed Lactobacillus brevis ATCC 14869 in the utilization of agar hydrolysate to produce bioethanol and lactic acid through fermentation. As a single carbon source, galactose was not metabolized by L. brevis. However, L. brevis consumed galactose simultaneous to glucose and ceased cell growth after depletion of glucose. For complete use of galactose from agar hydrolysis, glucose need to beperiodically replenished into the growth medium. Overall, L. brevis successfully used agar hydrolysate and produced 17.2g/L of ethanoland 31.9g/Lof lactic acid. The maximum specific cell growth rate on galactose and glucose mixture was the same with the glucose-only medium at 0.12h-1. The molar product yields from glucose for lactic acid and ethanol were 1.02 and 0.95 respectively, equal to values obtained from the simultaneous utilization of glucose and galactose. In contribution to the ongoing efforts to utilize marine biomass, the relaxed CCR in Lactobacillus brevis ATCC 14869 was herein exploited to produce bioethanol and lactic acid from red seaweed hydrolysates.