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The growth and starch accumulation ability of two types of duckweeds ( Wolffia globosa ), designated as duckweeds J and B, respectively, were investigated under different nutrition conditions using HYPONeX. Both duckweeds J and B grew better in rich nutrient condition (5,000-fold diluted HYPONeX solution) than in poor nutrient condition (80,000-fold diluted HYPONeX solution). In terms of starch accumulation, duckweed J accumulated more starch in the rich nutrient condition, whereas duckweed B accumulated more starch in the poor nutrient condition. In the rich nutrient condition, the dry weight of duckweed J increased by about 5.1 folds and the accumulated starch content was about 22% (w/w) of dry duckweed after 1-week cultivation. In the poor nutrient condition, the dry weight of duckweed B increased by about 5.0 folds and the accumulated starch content was about 28% (w/w) of dry duckweed after 1-week cultivation. Furthermore, ethanol production from the duckweeds was investigated using Saccharomyces cerevisiae NBRC0224. The most effective pretreatment of duckweeds for ethanol production was treatment with 1% hydrogen peroxide for 1 h, followed by treatment with 1% sodium hydroxide for 1 h. In the case of the duckweed J, 69 g/L ethanol was produced from 30% (w/v) of the pretreated duckweed with 20 mM urea or 0.1% yeast extract and 30 mM ammonium sulfate. In the case of the duckweed B, 30 g/L ethanol was produced from 30% (w/v) of the non-pretreated duckweed without nitrogen source. In conclusion, the duckweeds, W. globosa , were found to be a promising renewable carbon source for the production of third-generation bioethanol. [ABSTRACT FROM AUTHOR]

This study shows an evaluation of the method to improve acid tolerance of probiotic bacteria aimed at enhancement of the probiotic effects in the intestinal canal. In the tolerance test of simulated digestive juice in vitro , the viable rate of Lactobacillus brevis subsp. coagulans ( Labre ) processed with chocolate ( Labre -in-chocolate) is significantly increased, approximately one hundred times higher, compared to those of freeze-dried Labre powder and Labre contained in beverage. This protective effect depends on the content of water in chocolate for the probiotics processing. Differences in tolerance of metabolic activity were investigated with Labre -in-chocolate and freeze-dried Labre powder, both treated with simulated digestive juice in vitro . The enzyme activity of Labre -in-chocolate remained significantly even though that of the freeze-dried Labre powder was inactivated. These results indicate that chocolate processing is an effective method making probiotics to be delivered to the intestine in a viable condition and to be effective for host health. [ABSTRACT FROM AUTHOR]

Clostridioides difficile causes nosocomial antibiotic-associated diarrhea on a global scale. Susceptibility to C. difficile infection (CDI) is influenced by the composition and metabolism of gut microbiota, which in turn are affected by diet. However, the mechanism underlying the interplay between diet and gut microbiota that modulates susceptibility to CDI remains unclear. Here, we show that a soy protein diet increases the mortality of antibiotic-treated, C. difficile -infected mice while also enhancing the intestinal levels of amino acids (aas) and relative abundance of Lactobacillus genus. Indeed, Ligilactobacillus murinus -mediated fermentation of soy protein results in the generation of aas, thereby promoting C. difficile growth, and the process involves the anchored cell wall proteinase PrtP. Thus, mutual interaction between dietary protein and the gut microbiota is a critical factor affecting host susceptibility to CDI, suggesting that dietary protein sources can be an important determinant in controlling the disease. [Display omitted] • A soy protein diet increases the susceptibility to C. difficile infection • A soy protein diet increases the gut amino acids, which promote C. difficile growth • A soy protein diet enhances the relative abundance of Lactobacillus genus • Lactobacillus supplies gut amino acids by digestion of soy protein Susceptibility to Clostridioides difficile infection is influenced by gut microbiota and diet. Yakabe et al. demonstrate that soy protein promotes the growth of C. difficile by enhancing the intestinal levels of amino acids (aas). Furthermore, soy protein enhances the relative abundance of Lactobacillus , which digests soy protein to generate aas. [ABSTRACT FROM AUTHOR]

Various hydroxy-, oxo-, and conjugated fatty acids are generated by gut microbes throughout the metabolism of dietary PUFAs. Specifically, 10-Hydroxy-cis-12-(HYA), 10-oxo-cis12-(KetoA) and 10-oxo-cis9,trans11-octadecenoic acid (KetoC) are intermediates free fatty acids (iFFA) produced during the isomerization of dietary linoleic acid to cis9,trans11 (c9,t11) isomer of conjugated linoleic acid (CLA). Herein, immunomodulatory and antioxidant activity of selected iFFA was studied in resting (iDCs), LPS-matured DCs (mDCs) and in murine enterocyte cells (MODE-K). Phenotypic maturation of iDCs was not influenced by iFFA, but the release of pro-inflammatory molecules from mDCs was reduced following HYA pre-treatment. HYA ability to improve antioxidant/detoxifying defenses associated with decreased expression of maturation markers in mDCs and in MODE-K cells. The pro-oxidant activity, via NADPH oxidase activation, was responsible for the pro-inflammatory effect of 10-hydroxy-octadecanoic acid. Presented data suggest that the immunomodulatory ability of HYA is determined, at least in part, by its ability to improve antioxidant/detoxifying defenses. [ABSTRACT FROM AUTHOR]

Strain D2 was isolated from a natural sample as a crude glycerol-assimilating microorganism. The ITS-5.8S rDNA sequence of strain D2 was most similar to that of Fusarium solani deposited in the NCBI database. Strain D2 accumulated 10-hydroxy- cis -12-octadecenoic acid (HYA), 10-hydroxyoctadecanoic acid (HYB), and 10-oxooctadecanoic acid (KetoB) in a medium containing crude glycerol, as a carbon source, and yeast extract, named CG medium. The growth and HYB production of strain D2 depended on the crude glycerol concentration in the medium. Strain D2 produced 2.20 g/L (40% of total fatty acids) of HYB on cultivation in CG medium containing 8% crude glycerol. When strain D2 was cultivated in CG medium containing 6% crude glycerol, the yield of HYB on cultivation under 4 days-shaking and 3 days-static conditions reached 1.19 g/L, which was 2.2 times higher than that under 7 days-shaking conditions and accounted for 53% of total fatty acids. The fungus was found not only to efficiently produce fatty acids utilizing crude glycerol, but also to be the first filamentous fungus to produce hydroxy and oxo fatty acids such as HYB, HYA, and KetoB. • Strain D2, which produces hydroxy fatty acids by using crude glycerol, was isolated. • Strain D2 was found to be closely related to Fusarium solani. • 10-Hydroxy- cis -12-octadecenoic acid and 10-hydroxyoctadecanoic acid were detected. • The yield of hydroxy fatty acid increased under microaerobic conditions. [ABSTRACT FROM AUTHOR]

A ω3-fatty acid desaturase gene (maw3) which is involved in biosynthesis of n-3 polyunsaturated fatty acids (PUFAs) was previously isolated from Mortierella alpina 1S-4. In this report, we investigated the products of MAW3 catalyzing reaction with endogenous and exogenous fatty acids in the yeast transformant. Two unusual fatty acids de novo synthesized in the yeast transformant expressing maw3 gene were identified as n-4 hexadecadienoic acid (16:29cis,12cis ) and n-1 hexadecatrienoic acid (16:39cis,12cis,15) by GC–MS and 1H NMR analyses. In addition to the desaturation activity at the ω3-position for 18- and 20-carbon PUFAs, MAW3 in the yeast transformant inserted a double bond at Δ12-position of endogenous palmitoleic acid (16:19cis ) and further at Δ15-position of the resulting 16:29cis,12cis to result in the formation of 16:39cis,12cis,15 leading to a bifunctional Δ12/Δ15-desaturase for 16-carbon fatty acids. Moreover, we evaluated the activity of MAW3 in the yeast transformant under different temperatures. The MAW3 did not have desaturation activities in M. alpina 1S-4 at 28°C but it had in the yeast transformant for various fatty acids. The MAW3 was demonstrated to be a trifunctional Δ12/Δ15/ω3-desaturase, exhibiting Δ12-desaturation for 16:19cis , Δ15-desaturation for 16- and 18-carbon fatty acids that had a preexisting cis-double bond at Δ12 position, and ω3-desaturation for 20-carbon fatty acids having that at Δ14-position. It is the first report that the fatty acid desaturase (MAW3) is shown to have Δ12- and Δ15-desaturation activities for a 16-carbon fatty acid, in addition to its major function, ω3-desaturation activity. [ABSTRACT FROM AUTHOR]

The conditions for conjugated linoleic acid (CLA) production from castor oil, in which the main fatty acid component is ricinoleic acid, were investigated using washed cells of Lactobacillus plantarum JCM 1551 as the catalyst. In the presence of lipase, castor oil became an effective substrate for CLA production by the bacterium. Lipase M “Amano” 10 supported CLA production most effectively among the lipases tested. The addition of a detergent, especially Lubrol PX, enhanced the CLA production. The CLA produced comprised a mixture of two isomers, i.e. cis-9,trans-11-octadecadienoic acid (CLA1) and trans-9,trans-11-octadecadienoic acid (CLA2). Under the optimum conditions (1.0 M sodium citrate buffer, pH 6.0, 37 °C) with castor oil as the substrate and washed cells of L. plantarum (12%, wet cell w/v) as the catalyst, 2.7 mg/ml CLA was produced from 5.0 mg/ml castor oil in 99 h (productivity, 0.027 mg/ml/h), and 7.5 mg/ml CLA from 30 mg/ml castor oil in 171 h (productivity, 0.044 mg/ml/h). In the former case, the CLA produced accounted for 45.5% of the total fatty acids obtained, and consisted of CLA1 (26%) and CLA2 (74%). [Copyright &y& Elsevier]

Microorganisms in animal gut produce unusual fatty acids from the ingested diet. Two types of hydroxy fatty acids (HFAs), 10-hydroxy- cis -12-octadecenoic acid (HYA) and 10-hydroxy-octadecanoic acid (HYB), are linoleic acid (LA) metabolites produced by Lactobacillus plantarum. In this study, we investigated the metabolism of these HFAs in mammalian cells. When Chinese hamster ovary (CHO) cells were cultured with HYA, approximately 50% of the supplemented HYA disappeared from the dish within 24 h. On the other hand, the amount of HYA that disappeared from the dish of peroxisome (PEX)-deficient CHO cells was lower than 20%. Significant amounts of C2– and C4-chain-shortened metabolites of HYA were detected in culture medium of HYA-supplemented CHO cells, but not in medium of PEX-deficient cells. These results suggested that peroxisomal β-oxidation is involved in the disappearance of HYA. The PEX-dependent disappearance was observed in the experiment with HYB, but not with LA. We also found that HYA treatment up-regulates peroxisomal β-oxidation activity of human gastric MKN74 cells and intestinal Caco-2 cells. These results indicate a possibility that HFAs produced from gut bacteria affect lipid metabolism of host via modulation of peroxisomal β-oxidation activity. • Hydroxy fatty acids (HFAs) from gut microbiota were β-oxidized in peroxisome. • Most of incorporated HFAs were eliminated rather than acylated to cellular lipids. • HYA up-regulated peroxisomal β-oxidation activity in gastrointestinal cells. [ABSTRACT FROM AUTHOR]

The aim of this work was to study the molecular breeding of oleaginous filamentous Mortierella alpina for high production of linoleic (LA) or oleic acid (OA). Heterologous expression of the Δ12-desaturase (DS) gene derived from Coprinopsis cinerea in the Δ6DS activity-defective mutant of M. alpina increased the LA production rate as to total fatty acid to 5 times that in the wild strain. By suppressing the endogenous Δ6I gene expression by RNAi in the Δ12DS activity-defective mutant of M. alpina , the OA accumulation rate as to total fatty acid reached 68.0%. The production of LA and OA in these transformants reached 1.44 and 2.76 g/L, respectively, on the 5th day. The Δ6I transcriptional levels of the RNAi-treated strains were suppressed to 1/10th that in the parent strain. The amount of Δ6II RNA in the Δ6I RNAi-treated strain increased to 8 times that in the wild strain. [ABSTRACT FROM AUTHOR]

Highlights: [•] A new enzyme, which oxidizes a wide variety of ω-amino compounds, was found from Phialemonium sp. AIU 274. [•] The enzyme was specific to ω-amino compounds, and did not oxidize l- and d-amino acids. [•] The enzyme preferably oxidized medium- and long-chain ω-amino compounds to the corresponding aldehyde compounds. [•] The enzyme contained copper, and the enzyme activity was inhibited by isoniazid, iproniazid and semicarbazide. [ABSTRACT FROM AUTHOR]

• This study is to non-destructively estimate catechin concentrations in green tea shoots using spectral imagery. • Hyperspectral image sensor is used to extract the spectral attributes of green tea shoots. • Catechin concentrations grown in commercial or organic fertilizers are estimated. • The possibility of developing a year-invariant model is presented with mutual prediction. • The direction for model improvement is proposed by comparing the weights of variables. Hyperspectral imagery was applied to estimating non-galloyl (EC, EGC) and galloyl (ECG, EGCG) types of catechins in new shoots of green tea. Partial least squares regression models were developed to consider the effects of commercial fertilizer (CF) and organic fertilizer (OF). The models could explain each type of catechin with a precision of more than 0.79, with a few exceptions. When the CF model was applied to the OF hyperspectral reflectance and the OF model was applied to the CF hyperspectral reflectance for mutual prediction, the prediction accuracy was better with the OF models than CF models. The prediction models using both CF and OF data (hyperspectral reflectances, and concentrations of catechins) had a precision of more than 0.76 except for the non-galloyl-type catechins as a group and EGC alone. These results provide useful data for maintaining and improving the quality of green tea. [ABSTRACT FROM AUTHOR]

[Display omitted] • Serine 218 in FA-HY1 hydratase binding site affects regioselectivity of hydration. • Site-saturation mutagenesis rendered mutants with altered regioselectivity towards EPA. • A novel 15-hydroxy EPA product obtained with moderate regioselectivity. • Over 60 % conversion level for EPA can be achieved with a mutant whole cell catalyst. • Structural, kinetic and regression analysis provides the basis for observed changes. Fatty acid hydratase (FAH) mediated hydroxy fatty acid (HFA) production is a promising enzymatic route that demands diversification of hydration position to access a broader range of high-value HFAs. FA-HY1 is a promiscuous FAH from Lactobacillus Acidophilus , whereas its homolog from the same organism, FA-HY2, is strict in substrate scope and regioselectivity. Our earlier work demonstrated that three amino acid mutations at the carboxylate end of the substrate (T391/H393/I378 in FA-HY2) shift regioselectivity of FA-HY2 towards that of FA-HY1. Here, we explore alanine 216 of FA-HY2 as a hot-spot residue at the omega end of the substrate. A quadruple mutant (T391S/H393S/I378 P/A216S) demonstrates further shift in regioselectivity towards FA-HY1. Moreover, site-saturation mutagenesis of this residue in FA-HY1 (S218) led to novel variants exhibiting significant changes in regioselectivity for EPA (eicosapentaenoic acid) as substrate, where, unlike wild-type enzyme, 15-OH product was the dominant product (63:37 for wild-type vs. 26:74 for S218I mutant; 12-OH:15-OH). Alterations in conversion levels that indicate pronounced correlation to the exchanged residue type were also detected. A likely explanation for the observed differences is provided based on structural, statistical and kinetic analysis. [ABSTRACT FROM AUTHOR]

• KetoC induces the expression of antioxidant-related genes in GECs. • KetoC exerts a protective function against oxidative stress via GPR120-ERK-Nrf2-ARE. • KetoC could be a potential therapeutic application for periodontal disease. Oxidative stress, which is defined as an imbalance between pro-oxidant and antioxidant systems, has been implicated in the development and/or progression of several inflammatory diseases, including periodontal disease. The reactive oxygen species (ROS) are the primary inducers of oxidative stress. In the induction of cytoprotective enzymes, the nuclear factor erythroid 2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling in antioxidant systems takes a main role. Notably, 10-oxo- trans -11-octadecenoic acid (KetoC), known as a bioactive metabolite generated by intestinal microorganisms, has been reported to have beneficial effects on several biological responses. Therefore, we investigated the antioxidant effect of KetoC on gingival epithelial cells (GECs) in this present study. An SV40-T antigen-transformed human gingival epithelial cell line (Epi4) was used for experiments. The alteration of anti-oxidative stress related genes was analyzed by qPCR. The cellular ROS levels were evaluated by flow cytometry. To explore its molecular mechanisms, ARE promotor activity was analyzed by luciferase assay; the involvement of mitogen-activated protein kinase (MAPK) and G protein-coupled receptor 120 (GPR120) were evaluated by Western blotting and luciferase assay, respectively. KetoC significantly increased the expression of antioxidant-related genes in GECs. The level of ROS was significantly inhibited by the pretreatment of KetoC. Extracellular signal-regulated kinase (ERK) phosphorylation by KetoC promoted both the nuclear translocation of Nrf2 and its binding to the ARE in GECs. Further, GPR120 regulated the activation of KetoC induced-Nrf2-ARE signaling. KetoC exerts a protective function against the oxidative stress in GECs through GPR120-dependent ERK-Nrf2-ARE signaling. [ABSTRACT FROM AUTHOR]