Biotransformation of Tebuconazole by Microorganisms: Evidence of a Common Mechanism

A major problem with organic wood preservatives is biotransformation by both wood decaying and wood-inhabiting but nondecaying microorganisms in long-term service. Detoxification of organic biocides may contribute significantly to treated wood failure. In this study, a bacterium (Pseudomonas fluorescens), mold (Trichoderma harzianum), soft rot (Chaetomium globosum), white rot (Phanerochaete chrysosporium), and brown rot (Meruliporia. incrassata) were used to access the extent of biotransformation and the initial metabolite products of tebuconazole in liquid cultures. This study proposed metabolic pathway(s) and explored the possibility of a common biotransformation mechanism for all species. P. chrysosporium showed little ability to metabolize tebuconazole. Within 21 da, 40.4, 59.9, 68.2, and 70.2% tebuconazole was metabolized by M. incrassata, C. globosum, T. harzianum, and P. fluorescens, respectively, into a form that may be less toxic. Mass spectroscopy and infrared analysis of isolated metabolites indicated that the major pathway was cleavage of the triazole ring on tebuconazole and that most species mainly performed oxidation reactions to form the alcohol monolog, which was further oxidized to form the carboxylic acid analog of tebuconazole. Only T. harzianum metabolized the hydroxyl group on the tert-butyl moiety by acetylation to form an ester

An extract of Urtica dioica L. mitigates obesity induced insulin resistance in mice skeletal muscle via protein phosphatase 2A (PP2A)

The leaf extract of Urtica dioica L. (UT) has been reported to improve glucose homeostasis in vivo, but definitive studies on efficacy and mechanism of action are lacking. We investigated the effects of UT on obesity-induced insulin resistance in skeletal muscle. Male C57BL/6J mice were divided into three groups: low-fat diet (LFD), high-fat diet (HFD) and HFD supplemented with UT. Body weight, body composition, plasma glucose and plasma insulin were monitored. Skeletal muscle (gastrocnemius) was analyzed for insulin sensitivity, ceramide accumulation and the post translational modification and activity of protein phosphatase 2A (PP2A). PP2A is activated by ceramides and dephosphorylates Akt. C2C12 myotubes exposed to excess free fatty acids with or without UT were also evaluated for insulin signaling and modulation of PP2A. The HFD induced insulin resistance, increased fasting plasma glucose, enhanced ceramide accumulation and PP2A activity in skeletal muscle. Supplementation with UT improved plasma glucose homeostasis and enhanced skeletal muscle insulin sensitivity without affecting body weight and body composition. In myotubes, UT attenuated the ability of FFAs to induce insulin resistance and PP2A hyperactivity without affecting ceramide accumulation and PP2A expression. UT decreased PP2A activity through posttranslational modification that was accompanied by a reduction in Akt dephosphorylation

Kale Attenuates Inflammation and Modulates Gut Microbial Composition and Function in C57BL/6J Mice with Diet-Induced Obesity

Kale (Brassica oleracea var. acephala) is a vegetable common in most cultures but is less studied as a functional food compared to other cruciferous vegetables, such as broccoli. We investigated the effect of supplementing a high-fat diet (HFD) with kale (HFKV) in C57BL/6J mice. We particularly explored its role in metabolic parameters, gut bacterial composition and diversity using 16S rRNA sequencing, systematically compared changes under each phylum and predicted the functional potential of the altered bacterial community using PICRUSt2. Like other cruciferous vegetables, kale attenuated HFD-induced inflammation. In addition, kale modulated HFD-induced changes in cecal microbiota composition. The HFD lowered bacterial diversity, increased the Firmicutes: Bacteroidetes (F/B) ratio and altered composition. Specifically, it lowered Actinobacteria and Bacteroidetes (Bacteroidia, Rikenellaceae and Prevotellaceae) but increased Firmicutes (mainly class Bacilli). Kale supplementation lowered the F/B ratio, increased both alpha and beta diversity and reduced class Bacilli and Erysipelotrichi but had no effect on Clostridia. Within Actinobacteria, HFKV particularly increased Coriobacteriales/Coriobacteriaceae about four-fold compared to the HFD (p < 0.05). Among Bacteroidia, HFKV increased the species Bacteroides thetaiotaomicron by over two-fold (p = 0.05) compared to the HFD. This species produces plant polysaccharide digesting enzymes. Compared to the HFD, kale supplementation enhanced several bacterial metabolic functions, including glycan degradation, thiamine metabolism and xenobiotic metabolism. Our findings provide evidence that kale is a functional food that modulates the microbiota and changes in inflammation phenotype.https://doi.org/10.3390/microorganisms902023

Fermenting kale (Brassica oleracea L.) enhances its functional food properties by increasing accessibility of key phytochemicals and reducing antinutritional factors

The properties of kale as a functional food are well established. We sought to determine how fermentation further enhances these properties. We tested different fermentation conditions: (i) spontaneous fermentation with naturally occurring bacteria, (ii) spontaneous fermentation with 2% salt, (iii) Lactococcus lactis, (iv) Lactobacillus acidophilus, (v) mixture of L. lactis and L. acidophilus, (vi) mixture of L. lactis, L. acidophilus, and Clostridium butyricum. We quantified selected bioactive components using high-performance liquid chromatography (HPLC) and antinutritional factors using a gravimetric method and spectrophotometry. We then determined (i) the antioxidant capacity of the vegetable, (ii) anti-inflammation capacity, and (iii) the surface microbiota composition by 16S sequencing. All fermentation methods imparted some benefits. However, fermentation with mixed culture of L. lactis and L. acidophilus was most effective in increasing polyphenols and sulforaphane accessibility, increasing antioxidant activity, and reducing antinutritional factors. Specifically, fermentation with L. lactis and L. acidophilus increased total polyphenols from 8.5 to 10.7 mgGAE/g (milligrams of gallium acid equivalent per gram) and sulforaphane from 960.8 to 1777 μg/g (microgram per gram) but decreased the antinutritional factors oxalate and tannin. Total oxalate was reduced by 49%, while tannin was reduced by 55%–65%. The antioxidant capacity was enhanced but not the anti-inflammation potential. Both unfermented and fermented kale protected equally against lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophages and prevented increases in inducible nitric oxide synthase (iNOS), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 messenger RNA (IL-6 mRNA) expression by 84.3%, 62%, 68%, and 85.5%, respectively. Unfermented and naturally fermented kale had high proportions of sulfur reducing Desulfubrio and Proteobacteria usually associated with inflammation. Fermenting with L. lactis and/or L. acidophilus changed the bacterial proportions, reducing the Proteobacteria while increasing the genera Lactobacilli and Lactococcus. In summary, fermentation enhances the well-known beneficial impacts of kale. Fermentation with mixed cultures of L. lactis and L. acidophilus imparts higher benefits compared to the single cultures or fermentation with native bacteria present in the vegetable.https://doi.org/10.1002/fsn3.419

Urtica dioica Whole Vegetable as a Functional Food Targeting Fat Accumulation and Insulin Resistance-a Preliminary Study in a Mouse Pre-Diabetic Model

The shoot of Urtica dioica is used in several cultures as a vegetable or herb. However, not much has been studied about the potential of this plant when consumed as a whole food/vegetable rather than an extract for dietary supplements. In a 12-week dietary intervention study, we tested the effect of U. dioica vegetable on high fat diet induced obesity and insulin resistance in C57BL/6J mice. Mice were fed ad libitum with isocaloric diets containing 10% fat or 45% fat with or without U. dioica. The diet supplemented with U. dioica attenuated high fat diet induced weight gain (p < 0.005; n = 9), fat accumulation in adipose tissue (p < 0.005; n = 9), and whole-body insulin resistance (HOMA-IR index) (p < 0.001; n = 9). Analysis of gene expression in skeletal muscle showed no effect on the constituents of the insulin signaling pathway (AKT, IRS proteins, PI3K, GLUT4, and insulin receptor). Notable genes that impact lipid or glucose metabolism and whose expression was changed by U. dioica include fasting induced adipocyte factor (FIAF) in adipose and skeletal muscle, peroxisome proliferator-activated receptor-α (Ppar-α) and forkhead box protein (FOXO1) in muscle and liver, and Carnitine palmitoyltransferase I (Cpt1) in liver (p < 0.01). We conclude that U. dioica vegetable protects against diet induced obesity through mechanisms involving lipid accumulation and glucose metabolism in skeletal muscle, liver, and adipose tissue.https://doi.org/10.3390/nu1204105

Resistance to Diet Induced Visceral Fat Accumulation in C57BL/6NTac Mice Is Associated with an Enriched Lactococcus in the Gut Microbiota and the Phenotype of Immune B Cells in Intestine and Adipose Tissue

Humans and rodents exhibit a divergent obesity phenotype where not all individuals exposed to a high calorie diet become obese. We hypothesized that in C57BL/6NTac mice, despite a shared genetic background and diet, variations in individual gut microbiota function, immune cell phenotype in the intestine and adipose determine predisposition to obesity. From a larger colony fed a high-fat (HF) diet (60% fat), we obtained twenty-four 18–22-week-old C57BL/6NTac mice. Twelve had responded to the diet, had higher body weight and were termed obese prone (OP). The other 12 had retained a lean frame and were termed obese resistant (OR). We singly housed them for three weeks, monitored food intake and determined insulin resistance, fat accumulation, and small intestinal and fecal gut microbial community membership and structure. From the lamina propria and adipose tissue, we determined the population of total and specific subsets of T and B cells. The OP mice with higher fat accumulation and insulin resistance harbored microbial communities with enhanced capacity for processing dietary sugars, lower alpha diversity, greater abundance of Lactobacilli and low abundance of Clostridia and Desulfobacterota. The OR with less fat accumulation retained insulin sensitivity and harbored microbial communities with enhanced capacity for processing and synthesizing amino acids and higher diversity and greater abundance of Lactococcus, Desulfobacterota and class Clostridia. The B cell phenotype in the lamina propria and mesenteric adipose tissue of OR mice was characterized by a higher population of IgA+ cells and B1b IgM+ cells, respectively, compared to the OP. We conclude that variable responses to the HF diet are associated with the function of individuals’ gut microbiota and immune responses in the lamina propria and adipose tissue

Abundance of the species Clostridium butyricum in the gut microbiota contributes to differences in obesity phenotype in outbred Sprague-Dawley CD rats

© 2020 Elsevier Inc. Objectives: Gut microbiota profiles contribute to differences in obesity phenotype. We examined the abundance of the species Clostridium butyricum in relation to obesity phenotype. Methods: In outbred Sprague -Dawley rats we examined effects of dietary fat, resistant starch (RS), and a microbiota transplant on obesity phenotype. Using targeted qPCR, we examined the abundance of total gut bacteria and C. butyricum in relation to the propensity of obesity prone and obesity resistant rats to accumulate abdominal fat. Results: Before inclusion of dietary RS, obesity resistant (OR) rats had higher amounts of total bacteria, and C. butyricum compared to obesity prone (OP) rats (P \u3c 0.005 in study I, P \u3c 0.0001 in study II). A high fat diet (HF) lowered C. butyricum levels while RS had no effect. Dietary RS elicited robust fermentation and increased total bacteria only in OP rats. In preparation for the transplant, antibiotics were administered to recipient rats. Four weeks thereafter, total bacteria levels were restored but, C. butyricum levels were not. The transplant between the two phenotypes had no effect on abundance of C. butyricum and obesity phenotype. Conclusions: While C. butyricum is a known saccharolytic, its proliferation is not enhanced by fermentation of resistant starch. C. butyricum maybe one of the species that constitute a core microbiota involved in energy storage and metabolism through mechanisms that are not yet known