Ellagic Acid Prevented Dextran-Sodium-Sulfate-Induced Colitis, Liver, and Brain Injury through Gut Microbiome Changes.

Inflammatory bowel disease (IBD) affects millions of people worldwide and is considered a significant risk factor for colorectal cancer. Recent in vivo and in vitro studies reported that ellagic acid (EA) exhibits important antioxidant and anti-inflammatory properties. In this study, we investigated the preventive effects of EA against dextran sulfate sodium (DSS)-induced acute colitis, liver, and brain injury in mice through the gut-liver-brain axis. Acute colitis, liver, and brain injury were induced by treatment with 5% (w/v) DSS in the drinking water for 7 days. Freshly prepared EA (60 mg/kg/day) was orally administered, while control (CON) group mice were treated similarly by daily oral administrations with a vehicle (water). All the mice were euthanized 24 h after the final treatment with EA. The blood, liver, colon, and brain samples were collected for further histological and biochemical analyses. Co-treatment with a physiologically relevant dose (60 mg/kg/day) of EA for 7 days significantly reduced the DSS-induced gut barrier dysfunction; endotoxemia; and inflammatory gut, liver, and brain injury in mice by modulating gut microbiota composition and inhibiting the elevated oxidative and nitrative stress marker proteins. Our results further demonstrated that the preventive effect of EA on the DSS-induced IBD mouse model was mediated by blocking the NF-κB and mitogen-activated protein kinase (MAPK) pathway. Therefore, EA co-treatment significantly attenuated the pro-inflammatory and oxidative stress markers by suppressing the activation of NF-κB/MAPK pathways in gut, liver, and brain injury. These results suggest that EA, effective in attenuating IBD in a mouse model, deserves further consideration as a potential therapeutic for the treatment of inflammatory diseases.

Protective Effects of Hemp (Cannabis sativa) Root Extracts against Insulin-Deficient Diabetes Mellitus In Mice.

The pharmacological potential of industrial hemp (Cannabis sativa) has been widely studied. However, the majority of studies have focused on cannabidiol, isolated from the inflorescence and leaf of the plant. In the present study, we evaluated the anti-diabetic potential of hemp root water (HWE) and ethanol extracts (HEE) in streptozotocin (STZ)-induced insulin-deficient diabetic mice. The administration of HWE and HEE ameliorated hyperglycemia and improved glucose homeostasis and islet function in STZ-treated mice (p < 0.05). HWE and HEE suppressed ß-cell apoptosis and cytokine-induced inflammatory signaling in the pancreas (p < 0.05). Moreover, HWE and HEE normalized insulin-signaling defects in skeletal muscles and apoptotic response in the liver and kidney induced by STZ (p < 0.05). Gas chromatography-mass spectrometry analysis of HWE and HEE showed possible active compounds which might be responsible for the observed anti-diabetic potential. These findings indicate the possible mechanisms by which hemp root extracts protect mice against insulin-deficient diabetes, and support the need for further studies geared towards the application of hemp root as a novel bioactive material.

Hemp-Derived Nanovesicles Protect Leaky Gut and Liver Injury in Dextran Sodium Sulfate-Induced Colitis.

Hemp (Cannabis sativa L.) is used for medicinal purposes owing to its anti-inflammatory and antioxidant activities. We evaluated the protective effect of nanovesicles isolated from hemp plant parts (root, seed, hemp sprout, and leaf) in dextran sulfate sodium (DSS)-induced colitis in mice. The particle sizes of root-derived nanovesicles (RNVs), seed-derived nanovesicles (SNVs), hemp sprout-derived nanovesicles (HSNVs), and leaf-derived nanovesicles (LNVs) were within the range of 100-200 nm as measured by nanoparticle tracking analysis. Acute colitis was induced in C57BL/N mice by 5% DSS in water provided for 7 days. RNVs were administered orally once a day, leading to the recovery of both the small intestine and colon lengths. RNVs, SNVs, and HSNVs restored the tight (ZO-1, claudin-4, occludin) and adherent junctions (E-cadherin and α-tubulin) in DSS-induced small intestine and colon injury. Additionally, RNVs markedly reduced NF-κB activation and oxidative stress proteins in DSS-induced small intestine and colon injury. Tight junction protein expression and epithelial cell permeability were elevated in RNV-, SNV-, and HSNV-treated T84 colon cells exposed to 2% DSS. Interestedly, RNVs, SNVs, HSNVs, and LNVs reduced ALT activity and liver regeneration marker proteins in DSS-induced liver injury. These results showed for the first time that hemp-derived nanovesicles (HNVs) exhibited a protective effect on DSS-induced gut leaky and liver injury through the gut-liver axis by inhibiting oxidative stress marker proteins.

Enhancement of the Antiobesity and Antioxidant Effect of Purple Sweet Potato Extracts and Enhancement of the Effects by Fermentation.

The browning of white adipocytes, which transforms energy-storing white adipocytes to heat-producing beige adipocytes, is considered a strategy against metabolic diseases. Several dietary compounds, such as anthocyanins, flavonoids, and phenolic acids, induce a brown adipocyte-like phenotype in white adipocytes. In this study, we demonstrated that purple sweet potato (Ipomoea batatas) extract (PSP) exhibited potent radical scavenging activity. In addition, PSP was found to contain large amounts of phenolic, flavonoid, and anthocyanin compounds; the amount of these compounds was affected by fermentation. Functionally, PSP-induced adipose browning in high-fat-diet (HFD)-induced obese mice. The administration of PSP significantly suppressed the body weight gain and abnormal expansion of white adipose tissues in the obese mice. The expression of adipose browning-related genes was higher in the inguinal white adipose tissues from the PSP-treated mice than those in the HFD-fed mice. Moreover, PSP-treated 3T3-L1 adipocytes formed multilocular lipid droplets, similar to those formed in the 3T3-L1 adipocytes treated with a browning induction cocktail. The PSP-treated cells had an increased expression level of mitochondria and lipolysis-related genes. The browning effects of PSP were enhanced by fermentation with Lactobacillus. This study, to our knowledge, is the first to identify a new mechanism to increase the antiobesity effects of PSP by inducing adipocyte browning of adipocytes.

A technique for the prevention of greenhouse whitefly (Trialeurodes vaporariorum) using the entomopathogenic fungus Beauveria bassiana M130.

The possibility of using hyphomycete fungi as suitable biocontrol agents against greenhouse whitefly has led to the isolation of various insect pathogenic fungi. Among them is Beauveria bassiana, one of the most studied entomopathogenic fungi. The objective of this study was to use B. bassiana M130 as an insecticidal agent against the greenhouse whitefly. M130 isolated from infected insects is known to be a biocontrol agent against greenhouse whitefly. Phylogenetic classification of M130 was determined according to its morphological features and 18S rRNA sequence analysis. M130 was identified as B. bassiana M130 and showed chitinase (342.28 units/ml) and protease (461.70 units/ml) activities, which were involved in the invasion of the host through the outer cuticle layer, thus killing them. The insecticidal activity was 55.2% in petri-dish test, 84.6% in pot test, and 45.3% in field test. The results of this study indicate that B. bassiana has potential as a biological agent for the control of greenhouse whitefly to replace chemical pesticides.

Wickerhamomyces ochangensis sp. nov., an ascomycetous yeast isolated from the soil of a potato field.

A novel ascomycetous yeast, designated strain N7a-Y2(T), was isolated from soil collected in a potato field in Ochang, Korea, and its taxonomic position was studied. A neighbour-joining tree based on the D1/D2 domain of large-subunit rRNA gene sequences revealed that the isolate was a member of the Wickerhamomyces clade and that it was closely related to Wickerhamomyces bisporus, Candida quercuum, Candida ulmi and Wickerhamomyces alni. Strain N7a-Y2(T) formed Saturn-shaped ascospores in unconjugated and persistent asci. D1/D2 domain 26S rRNA gene sequence divergences of 11.0-21.1 % between strain N7a-Y2(T) and other members of the Wickerhamomyces clade indicate that the strain represents a novel species of the genus Wickerhamomyces, for which the name Wickerhamomyces ochangensis sp. nov. is proposed. The type strain is N7a-Y2(T) ( = KCTC 17870(T)  = CBS 11843(T)).

Differential roles of the ChiB chitinase in autolysis and cell death of Aspergillus nidulans.

Autolysis is a natural event that occurs in most filamentous fungi. Such self-degradation of fungal cells becomes a predominant phenomenon in the absence of the regulator of G protein signaling FlbA in Aspergillus nidulans. Among a number of potential hydrolytic enzymes in the A. nidulans genome, the secreted endochitinase ChiB was shown to play a major role in autolysis. In this report, we investigate the roles of ChiB in fungal autolysis and cell death processes through genetic, biochemical, and cellular analyses using a set of critical mutants. Determination of mycelial mass revealed that, while the flbA deletion (DeltaflbA) mutant autolyzed completely after a 3-day incubation, the DeltaflbA DeltachiB double mutant escaped from hyphal disintegration. These results indicate that ChiB is necessary for the DeltaflbA-induced autolysis. However, importantly, both DeltaflbA and DeltaflbA DeltachiB strains displayed dramatically reduced cell viability compared to the wild type. These imply that ChiB is dispensable for cell death and that autolysis and cell death are separate processes. Liquid chromatography-tandem mass spectrometry analyses of the proteins that accumulate at high levels in the DeltaflbA and DeltaflbA DeltachiB mutants identify chitinase (ChiB), dipeptidyl peptidase V (DppV), O-glycosyl compound hydrolase, beta-N-acetylhexosaminidase (NagA), and myo-inositol-1-phosphate synthase (InoB). Functional characterization of these four genes reveals that the deletion of nagA results in reduced cell death. A working model bridging G protein signaling and players in autolysis/cell death is proposed.

Microbial biodegradation and toxicity of vinclozolin and its toxic metabolite 3,5-dichloroaniline.

Vinclozolin, an endocrine disrupting chemical, is a chlorinated fungicide widely used to control fungal diseases. However, its metabolite 3,5-dichloroaniline is more toxic and persistent than the parent vinclozolin. For the biodegradation of vinclozolin, vinclozolin- and/or 3,5-dichloroaniline-degrading bacteria were isolated from pesticide-polluted agriculture soil. Among the isolated bacteria, a Rhodococcus sp. was identified from a 16S rDNA sequence analysis and named Rhodococcus sp. T1-1. The degradation ratios for vinclozolin or 3,5- dichloroaniline in a minimal medium containing vinclozolin (200 microg/ml) or 3,5-dichloroaniline (120 microg/ml) were 90% and 84.1%, respectively. Moreover, Rhodococcus sp. T1-1 also showed an effective capability to biodegrade dichloroaniline isomers on enrichment cultures in which they were contained. Therefore, these results suggest that Rhodococcus sp. T1-1 can bioremediate vinclozolin as well as 3,5-dichloroaniline.

Isolation of a soil bacterium capable of biodegradation and detoxification of endosulfan and endosulfan sulfate.

Endosulfan, an endocrine disrupting chemical, is a widely used cyclodiene organochlorine pesticide worldwide, and it blocks neuronal GABA(A)-gated chloride channels in mammals and aquatic organisms. Endosulfan and its metabolites, such as endosulfan sulfate, are persistent in environments and are considered as toxic chemicals. For bioremediation of endosulfan, in this study, an attempt was made to isolate an endosulfan and endosulfan sulfate degrading bacterium from endosulfan-polluted agricultural soil. Through repetitive enrichment and successive subculture using endosulfan or endosulfan sulfate as the sole carbon source, a bacterium KS-2P was isolated. The KS-2P was identified as Pseudomonas sp. on the basis of the results of a 16S rDNA sequencing analysis and MIDI test. The degradation ratios for endosulfan or endosulfan sulfate in minimal medium containing endosulfan (23.5 microg mL(-1)) or endosulfan sulfate (21 microg mL(-1)) were 52% and 71%, respectively. Our results suggest that Pseudomonas sp. KS-2P has potential as a biocatalyst for endosulfan bioremediation.

Cryptococcus mujuensis sp. nov. and Cryptococcus cuniculi sp. nov., basidiomycetous yeasts isolated from wild rabbit faeces.

Two previously undescribed anamorphic yeasts, strains T-11(T) and T-26(T), recovered from wild rabbit faecal pellets collected in Muju, Korea, were identified using phenotypic and molecular taxonomic methods. The isolates were characterized by the proliferation of budding cells, positive diazonium blue B and urease reactions, the presence of Q-10 as the major ubiquinone, the presence of xylose in whole-cell hydrolysates and the inability to ferment sugars. Phylogenetic analyses based on 26S rRNA gene partial sequences revealed that strain T-11(T) was located in the Bulleromyces clade and was related to Sirobasidium intermedium, Tremella exigua, Cryptococcus cellulolyticus and Bullera pseudoalba. Strain T-26(T) was located in the Mesenterica clade and was closely related to Cryptococcus sp. F6 and Cryptococcus heveanensis CBS 8976. Sequence divergence values of more than 4 % from other described Cryptococcus species, together with the phenotypic differences, showed that the isolated yeasts represent previously unrecognized members of this genus. Therefore, two novel yeast species are proposed: Cryptococcus mujuensis sp. nov., with strain T-11(T) (=KCTC 17231(T)=CBS 10308(T)) as the type strain, and Cryptococcus cuniculi sp. nov., with strain T-26(T) (=KCTC 17232(T)=CBS 10309(T)) as the type strain.

GLR1 plays an essential role in the homeodynamics of glutathione and the regulation of H2S production during respiratory oscillation of Saccharomyces cerevisiae.

The role of glutathione (GSH) and its homeodynamics during respiratory oscillation of Saccharomyces cerevisiae were investigated. Pulse injection of thiol redox modifying agents, such as diethylmaleate, N-ethylmaleimide, DL-butione-[S,R]-sulfoxamine, or 5-nitro-2-furaldehyde into the culture perturbed oscillation, although the degree of perturbation varied. Analysis of the expression profiles of GSH1 and GLR1, the activities of glutathione reductase, oscillations in cysteine and GSH concentrations, and the chemostat culture of the GLR1 disruptant indicated that GLR1 plays an essential role in the homeodynamics of GSH and the regulation of H(2)S production.

Regulation of branched-chain, and sulfur-containing amino acid metabolism by glutathione during ultradian metabolic oscillation of Saccharomyces cerevisiae.

Autonomous ultradian metabolic oscillation (T approximately or =50 min) was detected in an aerobic chemostat culture of Saccharomyces cerevisiae. A pulse injection of GSH (a reduced form of glutathione) into the culture induced a perturbation in metabolic oscillation, with respiratory inhibition caused by H2S burst production. As the production of H2S in the culture was controlled by different amino acids, we attempted to characterize the effects of GSH on amino acid metabolism, particularly with regard to branched chain and sulfur-containing amino acids. During stable metabolic oscillation, concentrations of intracellular glutamate, aspartate, threonine, valine, leucine, isoleucine, and cysteine were observed to oscillate with the same periods of dissolved O2 oscillation, although the oscillation amplitudes and maximal phases were shown to differ. The methionine concentration was stably maintained at 0.05 mM. When GSH (100 microM) was injected into the culture, cellular levels of branched chain amino acids increased dramatically with continuous H2S production, whereas the cysteine and methionine concentrations were noticeably reduced. These results indicate that GSH-dependent perturbation occurs as the result of the promotion of branched chain amino acid synthesis and an attenuation of cysteine and methionine synthesis, both of which activate the generation of H2S. In a low sulfate medium containing 2.5 mM sulfate, the GSH injections did not result in perturbations of dissolved O2, NAD(P)H redox oscillations without burst H2 production. This suggests that GSH-dependent perturbation is intimately linked with the metabolism of branched-chain amino acids and H2 generation, rather than with direct GSH-GSSG redox control.

Identification of two-component regulatory genes involved in o-xylene degradation by Rhodococcus sp. strain DK17.

Putative genes for a two-component signal transduction system (akbS and akbT) were detected near the alkylbenzene-degrading operon of Rhodococcus sp. DK17. Sequence analysis indicates that AkbS possesses potential ATP-binding and histidine autophosphorylation sites in the N- and C-terminal regions, respectively, and that AkbT has a typical response regulator domain. Mutant analysis combined with RT-PCR experiments further shows that AkbS is required to induce the expression of o-xylene dioxygenase in DK17.

Biodegradation of the organochlorine insecticide, endosulfan, and the toxic metabolite, endosulfan sulfate, by Klebsiella oxytoca KE-8.

Biodegradation of endosulfan, a chlorinated cyclodiene insecticide, is generally accompanied by production of the more toxic and more persistent metabolite, endosulfan sulfate. Since our reported endosulfan degrader, Klebsiella pneumoniae KE-1, failed to degrade endosulfan sulfate, we tried to isolate an endosulfan sulfate degrader from endosulfan-polluted soils. Through repetitive enrichment and successive subculture using mineral salt medium containing endosulfan or endosulfan sulfate as the sole source of carbon and energy, we isolated a bacterium capable of degrading endosulfan sulfate as well as endosulfan. The bacterium KE-8 was identified as Klebsiella oxytoca from the results of 16S rDNA sequence analysis. In biodegradation assays with KE-8 using mineral salt medium containing endosulfan (150 mg l(-1)) or endosulfan sulfate (173 mg l(-1)), the biomass was rapidly increased to an optical density at 550 nm of 1.9 in 4 days and the degradation constants for alpha- and beta-endosulfan, and endosulfan sulfate were 0.3084, 0.2983 and 0.2465 day(-1), respectively. Analysis of the metabolites further suggested that K. oxytoca KE-8 has high potential as a biocatalyst for bioremediation of endosulfan and/or endosulfan sulfate.

Catabolic role of a three-component salicylate oxygenase from Sphingomonas yanoikuyae B1 in polycyclic aromatic hydrocarbon degradation.

Sphingomonas yanoikuyae B1 possesses several different multicomponent oxygenases involved in metabolizing aromatic compounds. Six different pairs of genes encoding large and small subunits of oxygenase iron-sulfur protein components have previously been identified in a gene cluster involved in the degradation of both monocyclic and polycyclic aromatic hydrocarbons. Insertional inactivation of one of the oxygenase large subunit genes, bphA1c, results in a mutant strain unable to grow on naphthalene, phenanthrene, or salicylate. The knockout mutant accumulates salicylate from naphthalene and 1-hydroxy-2-naphthoic acid from phenanthrene indicating the loss of salicylate oxygenase activity. Complementation experiments verify that the salicylate oxygenase in S. yanoikuyae B1 is a three-component enzyme consisting of an oxygenase encoded by bphA2cA1c, a ferredoxin encoded by the adjacent bphA3, and a ferredoxin reductase encoded by bphA4 located over 25kb away. Expression of bphA3-bphA2c-bphA1c genes in Escherichia coli demonstrated the ability of salicylate oxygenase to convert salicylate to catechol and 3-, 4-, and 5-methylsalicylate to methylcatechols.

Induction of oxidative stress by endosulfan and protective effect of lipid-soluble antioxidants against endosulfan-induced oxidative damage.

The toxic mechanism of endosulfan, a widely used organochlorine pesticide, was investigated in Saccharomyces cerevisiae and human cell lines. A concentration-dependent inhibition of cell growth was observed when S. cerevisiae was exposed to endosulfan, and its cytotoxicity (IC(50)) was found to be 49 microM and 86 microM in HepG2 and HeLa human cell lines, respectively. The treatment of S. cerevisiae with endosulfan resulted in oxidative damage, as demonstrated by thiobarbituric acid-reactive substance (TBARS) production, in a dose-dependent manner, and the growth inhibition was recovered by treatment with lipid-soluble antioxidants, such as alpha-tocopherol or beta-carotene, suggesting that endosulfan toxicity may be closely associated with endosulfan-induced reactive oxygen species (ROS) generation. The inhibition of cellular respiration by endosulfan treatment and the recovery of respiration activity by antioxidant treatment confirmed that endosulfan induces oxidative stress and inhibits respiration via ROS generation. These results suggest that unicellular yeast might provide a useful system for elucidating the toxicity of endosulfan.

Biotransformation of an organochlorine insecticide, endosulfan, by Anabaena species.

This study assesses the role of the blue-green algal species present in the soil in the dissipation of endosulfan and its metabolites in the soil environment. Two Anabaena species, Anabaena sp. PCC 7120 and Anabaena flos-aquae, were used in this study. Anabaena sp. PCC 7120 produced three principal biotransformation compounds, chiefly endosulfan diol (endodiol), and minor amounts of endosulfan hydroxyether and endosulfan lactone. Trace amounts of endosulfan sulfate were detected. In comparison, the biotransformation of endosulfan by Anabaena flos-aquae yielded mainly endodiol with minor amounts of endosulfan sulfate. An unknown compound was produced up to 70% from endosulfan spiked in the medium inoculated by A. flos-aquae after 8 days of incubation. Therefore, the endosulfan fate was dependent on the species. Within 1 day of incubation, two Anabaena species produced low amounts of beta-endosulfan after application of alpha-endosulfan. These results suggest the presence of isomerase in the Anabaena species. Further studies using a fermentor to control the medium pH at 7.2 to minimize chemical hydrolysis of endosulfan revealed a major production of endodiol with minor amounts of endosulfan sulfate and the unknown compound. These results showed that the production of the unknown compound might be dependent on the alkaline pH in the medium and that the production of endodiol by A. flos-aquae might be biologically controlled. This study showed that two algal species could contribute in the detoxification pathways of endosulfan in the soil environment.

Involvement of oxidative stress in the regulation of H(2)S production during ultradian metabolic oscillation of Saccharomyces cerevisiae.

Periodic evolution of H(2)S during aerobic chemostat culture of Saccharomyces cerevisiae resulted in ultradian metabolic oscillation via periodic inhibition of respiratory activity. To understand the nature of periodic H(2)S evolution, we investigated whether oxidative stress is associated with H(2)S production. The cellular oxidative states represented by intracellular level of lipid peroxides oscillated out of phase with the oscillation of dissolved O(2). Pulse addition of antioxidant, oxidative agent or inhibitor of antioxidation enzymes perturbed metabolic oscillation producing changes in H(2)S evolution. Analysis of H(2)S production profiles during perturbation of oscillation revealed that the amount of H(2)S production is closely linked with cellular oxidative states. Based on these results and our previous reports, we suggest that oxidative stresses result in periodic depletion of glutathione and cysteine, which in turn causes stimulation of the sulfate assimilation pathway and H(2)S production.

Klebsiella pneumoniae KE-1 degrades endosulfan without formation of the toxic metabolite, endosulfan sulfate.

For bioremediation of toxic endosulfan, endosulfan degradation bacteria, which do not form toxic endosulfan sulfate, were isolated from various soil samples using endosulfan as sole carbon and energy source. Among the 40 isolated bacteria, strain KE-1, which was identified as Klebsiella pneumoniae by physiological and 16S rDNA sequence analysis, showed superior endosulfan degradation activity. Analysis of culture pH, growth, free sulfate and endosulfan and its metabolites demonstrated that KE-1 biologically degrades 8.72 microg endosulfan ml(-1) day(-1) when incubated with 93.9 microg ml(-1) endosulfan for 10 days without formation of toxic endosulfan sulfate. Our results suggest that K. pneumoniae KE-1 degraded endosulfan by a non-oxidative pathway and that strain KE-1 has potential as a biocatalyst for endosulfan bioremediation.