Lysobacter erysipheiresistens sp. nov., an antagonist of powdery mildew, isolated from tobacco-cultivated soil.

A bacterial strain, RS-LYSO-3T, was isolated from tobacco-cultivated soil, collected near Chuxiong, Yunnan province, southwestern China. RS-LYSO-3T could effectively inhibit the invasion of powdery mildew on tobacco. The colonies of RS-LYSO-3T were pale yellow, and its cells were Gram-stain-negative and rod-shaped, with 68 mol% DNA G+C content. Gene sequence analysis for its 16S rRNA gene revealed the highest similarity (97.78 %) with that of Lysobacter spongiicolaKMM 329T. Chemotaxonomic data showed that RS-LYSO-3T possesses a quinone system with Q-8, and iso-C16 : 0, summed feature 9 and iso-C15 : 0 as the predominant fatty acids, all of which support the affiliation of RS-LYSO-3T to the genus Lysobacter. The results of DNA-DNA hybridization, physiological and biochemical tests clearly proved that RS-LYSO-3T is a representative of a novel species of the genus Lysobacter, for which the name Lysobacter erysipheresistens sp. nov. is proposed. The type strain is RS-LYSO-3T (=CCIC 23922T=JCM 31042T).

Progress in the application of Enterococcus faecium in animal husbandry.

As a probiotic, enterococcus faecium (E. faecium) has the characteristics of high temperature resistance, gastric acid resistance, bile salt resistance, etc. It can also effectively improve animal performance and immunity and improve the animal's intestinal environment, so in recent years it has been more widely used in the livestock industry. However, due to the improper use of antibiotics and the growing environmental stress of strains, the drug resistance of enterococcus faecium has become more and more serious, and because some enterococcus faecium carry virulence genes, leading to the emergence of pathogenic strains, its safety issues have been widely concerned. This paper focuses on the biological characteristics of enterococcus faecium, the application of this bacterium in animal husbandry and the safety issues in its use, with a view to providing a reference for the application of enterococcus faecium in the development of animal husbandry.

Oenothein B ameliorates hepatic injury in alcoholic liver disease mice by improving oxidative stress and inflammation and modulating the gut microbiota.

Introduction: Alcoholic liver disease (ALD) is a global health problem for which there is no current food and drug administration (FDA)-approved therapy. Oenothein B (OEB) is a macrocyclic dimer ellagic tannin that possesses abundant biological activities including antioxidant, anti-inflammation, antitumor, immunomodulatory, and antimicrobial properties. Materials and methods: In this study, the hepatoprotective effect of OEB against ALD was investigated in vivo and in vitro. Results: We found that OEB treatment dramatically reduced alcohol-induced hepatic injury, as evidenced by decreased levels of aminotransferases and inflammatory biomarkers and increased antioxidant capacity in OEB-treated groups. Discussion: OEB treatment alleviated oxidative stress by upregulating the Keap1/Nrf2 signaling pathway and inhibited inflammation by downregulating the TLR4/NF-κB signaling pathway. Additionally, OEB treatment positively improved alcohol-induced intestinal microbial dysbiosis by modulating the structure and composition of gut microbiota. Interestingly, we observed the increasement of short-chain fatty acid (SCFA) producers (Muribaculaceae) and the decreasement of Gram-negative bacteria (Akkermansia) in the OEB treatment groups, which may contribute to the inhibition of hepatic oxidative stress and inflammation via the gut-liver axis. In summary, our findings indicate that OEB is a promising therapeutic strategy for preventing and treating ALD.

Bioactivity-guided isolation of anti-inflammatory components from Phyllanthus emblica.

Phyllanthus emblica (P. emblica) is a traditionally edible fruit that is good for treatment of biliary diseases, bronchitis, etc. It has obvious anti-inflammatory activity, but few studies focus on its anti-inflammatory active substance basis. The purpose of this study was to explore the material basis of anti-inflammatory activity of P. emblica, purify, and identify anti-inflammatory active monomers. Fisetin and gallic acid, which were identified after separation from ethanol extract components of P. emblica, exhibited the best anti-inflammatory effects, markedly inhibiting nitric oxide and proinflammatory cytokine levels in LPS-stimulated macrophages. In particular, fisetin with significant anti-inflammatory activity was firstly identified from P. emblica. For the first time, our research systematically revealed the material basis of the anti-inflammatory effects of P. emblica from the perspective of the composition of the bioactive substances and provided scientific research methods and ideas for researching bioactive monomers in other plant extracts.

Proteome and Transcriptome Analysis of the Antioxidant Mechanism in Chicken Regulated by Eucalyptus Leaf Polyphenols Extract.

Eucalyptus leaf polyphenols extract (EPE) has been proved to have various bioactivities, but few reports focus on its antioxidant mechanism in vivo. The purpose of this study was to elucidate the effect and mechanism of EPE dietary supplements on antioxidant capacity in chicken. A total of 216 chickens were randomly selected for a 40-day experiment. Four treatment groups received diets including the control diet only, the control diet + low EPE (0.6 g/kg), the control diet + moderate EPE (0.9 g/kg), and the control diet + high EPE (1.2 g/kg). Compared with control group, the glutathione peroxidase (GSH-Px) activity and glutathione (GSH) content in the breast muscle of the moderate EPE treatment group was significantly higher (p < 0.05), while the malonaldehyde (MDA) content in the moderate EPE group was reduced (p < 0.05). Moreover, proteomic and transcriptomic analyses of the breast muscle revealed that glutathione metabolism and the peroxisome were the two crucial metabolic pathways responsible for increased antioxidant capacity of the muscle. Accordingly, nine candidate genes and two candidate proteins were identified related to improved antioxidant status induced by EPE supplements. This research provides new insights into the molecular mechanism of antioxidant capacity in chickens treated with EPE dietary supplements.

RNA-seq-based quanitative transcriptome analysis of meat color and taste from chickens administered by eucalyptus leaf polyphenols extract.

To evaluate how eucalyptus leaf polyphenol extract (EPE) affects chicken meat color and taste, we added different levels of EPE (0%, 0.06%, 0.09%, and 0.12%) to chicken feed. The redness (a* value) and the myoglobin content of breast muscle in EPE group were remarkably higher. Furthermore, the guanosine monophosphate, histidine, and glycine muscle contents were also enhanced. Transcriptome analysis showed that 10 candidate genes related to meat quality were affected by EPE treatment. The identified genes, with functions critical to chicken meat color and taste, will help to determine the molecular mechanisms of EPE.

Extraction, structural characterization, and immunobiological activity of ABP Ia polysaccharide from Agaricus bisporus.

The extraction, purification, immunobiological activities, and structure of Agaricus bisporus polysaccharides (ABP) were investigated. Especially we purified and identified the polysaccharides with the highest in vitro immunobiological activity. The extraction conditions of ABP were optimized using single factor and orthogonal experiment. ABP Ia was screened after double purification with DEAE-52 and Sephadex G-200 and showed the best immunoregulatory activity. UV spectra analysis and high-performance gel permeation chromatography results indicated that the ABP Ia fraction did not contain any proteins or nucleotides and was a homogeneous polysaccharide with a relative molecular weight of 784 kDa. Gas chromatography mass spectroscopy results showed that ABP Ia was a heteropolysaccharide consisting of ribose, rhamnose, arabinose, xylose, mannose, glucose, and galactose at a molar ratio of 2.08:4.61:2.45:22.25:36.45:89.22:1.55. FT-IR and periodic acid oxidation analysis indicated that ABP Ia was an α-pyran polysaccharide composed of 1 â†’ 2 and 1 â†’ 4 glycosidic bonds, as well as a possible 1 â†’ 3 glycosidic bond. Furthermore, atomic force microscopy revealed that ABP Ia polysaccharide chains twisted to form a rod-like architecture and, at a 5% concentration, aggregated into a tight structure similar to the shape of a stone forest. These findings identify ABP Ia as a potential functional food ingredient or pharmaceutical for immunoregulation.

Protein phosphatase 2A-negative regulation of the protective signaling pathway of Ca2+/CaM-dependent ERK activation in cerebral ischemia.

Extracellular-signal-regulated kinase (ERK) undergoes rapid inactivation following the intense activation evoked by cerebral ischemia and reperfusion. However, the precise mechanism of this inactivation has not been elucidated. To investigate how phosphatases regulate the ERK cascade following ischemia, the PP2A inhibitors cantharidin and okadaic acid were administrated to the CA1 subregion of the rat hippocampus. The resulting sustained ERK activity implies that PP2A is a major phosphatase contributing to the rapid inactivation, but not activation, of ERK following cerebral ischemia. The increase in PP2A activity induced by ceramide has a weak effect on the activation of Raf via dephosphorylation of Ser259 in response to ischemia. In contrast, ketamine (Keta) and cyclosporine A (CsA), two chemicals that block calcium signal in ischemia, decrease ERK activity by blocking Raf dephosphorylation of Ser259. We also observed that activation of an upstream protein, Ras-GRF, leads to calcium/calmodulin-dependent activation of the ERK signaling cascade in response to ischemic stimuli. In addition, the activity of cyclic AMP response element-binding protein (CREB) and estrogen receptor alpha (ER alpha), target proteins of ERK and protective elements against ischemic lesion, parallels the activity of ERK. These data indicate that PP2A plays a significant role in blocking the protective effect induced by the ERK kinase pathway and that fast inactivation of ERK is the result of cross talk between calcium/calmodulin-dependent, positively regulated signal cascades and a ceramide-dependent negative signaling pathway.

Novel skeleton sesquiterpenoids isolated from guava leaves.

A chemical investigation of the plant Psidium guajava L., collected in Guangdong province, afforded two novel skeleton sesquiterpenoids 1 and 2. Compound 2 also known as isocaryolan-9-one was a new natural product. The structure of the novel compound 1 was determined as guavacid A by various spectroscopic methods. A possible biosynthetic pathway for 1 and 2 was proposed.