Enhancement of chlortetracycline biodegradation with Trichoderma harzianum LJ245 and its spore-producing mutants using co-metabolism.

Chlortetracycline (CTC) has been widely used in veterinary medicine in recent years, which has resulted in severe environmental issues due to its low degradation rate and high risk to induce antibiotic resistance bacteria and genes. In previous studies, CTC could be efficiently degraded by Trichoderma harzianum LJ245. Nevertheless, the strain itself suffers from relatively poor adaptability due to the limited number of spores produced. In this paper, ultraviolet (UV) mutagenesis was conducted on LJ245, and various mutants with high sporulation rate were generated to expand the environmental adaptability and enhance CTC degradation. An OmniLog-based method, where 95 types of carbon sources were applied, was first proposed to acquire the carbon metabolic profile of the strains. Several controlled experiments were performed to evaluate the impact of co-substrate metabolism on strain growth, CTC biodegradation, and metabolites biotoxicity removal. The result shows that produced mutants could significantly broaden the carbon metabolic profile and expand the environmental adaptability compared to the original LJ245, where the mutants obtained remarkable increase in total number of usable carbon sources. Meanwhile, as the sole carbon source, CTC could not be fully degraded by the strains. However, the use of co-metabolism could considerably enhance CTC degradation and completely remove CTC degradation products biotoxicity by all strains. Specifically, amino acids and carboxylic acids had the best performance on both strain growth and CTC degradation among all carbon source categories. The results can be applied to the biodegradation treatment of CTC in solid residue, waste water and other environments.

Imaging mass spectrometry-guided fast identification of antifungal secondary metabolites from Penicillium polonicum.

The discovery of antibiotics from microorganisms using classic bioactivity screens suffers from heavy labor and high re-discovery rate. Recently, largely uncovered biosynthetic potentials were unveiled by new approaches, such as genetic manipulation of "silent" biosynthetic gene clusters, innovative data acquisition, and processing methods. In this work, a fast and efficient antibiotic identification pipeline based on the MALDI-TOF imaging mass spectrometry was applied to study the antifungal metabolites during the confrontation of two fungal species, Penicillium polonicum and wilt-inducing fungus Fusarium oxysporum. By visualizing the spatial distribution of metabolites directly on the microbial colony and surrounding media, we predicted the antifungal candidates before isolating pure compounds and individually testing their bioactivity, which subsequently guided the identification of target molecules using classic chromatographic methods. Via this procedure, we successfully identified two antifungal metabolites, fructigenine A and B, which belong to indole alkaloid class and were not reported for antifungal activity. Our work assigned new bioactivity to previously reported compounds and more importantly showed the efficiency of this approach towards quick discovery of bioactive compounds, which can help study the vast unexploited synthetic potential of microbial secondary metabolites.

Haloprofundus marisrubri gen. nov., sp. nov., an extremely halophilic archaeon isolated from a brine-seawater interface.

We isolated a Gram-stain-negative, pink-pigmented, motile, pleomorphic, extremely halophilic archaeon from the brine-seawater interface of Discovery Deep in the Saudi Arabian Red Sea. This strain, designated SB9T, was capable of growth within a wide range of temperatures and salinity, but required MgCl2. Cells lysed in distilled water, but at 7.0 % (w/v) NaCl cell lysis was prevented. The major polar lipids from strain SB9T were phosphatidylglycerol, phosphatidylglycerolphosphate methyl ester, sulfated mannosyl glucosyl diether, mannosyl glucosyl diether, an unidentified glycolipid and two unidentified phospholipids. The major respiratory quinones of strain SB9T were menaquinones MK8 (66 %) and MK8 (VIII-H2) (34 %). Analysis of the 16S rRNA gene sequence revealed that strain SB9T was closely related to species in the genera Halogranum and Haloplanus; in particular, it shared highest sequence similarity with the type strain of Halogranum rubrum (93.4 %), making it its closest known relative. The unfinished draft genome of strain SB9Twas 3 931 127 bp in size with a total G+C content of 62.53 mol% and contained 3917 ORFs, 50 tRNAs and eight rRNAs. Based on comparisons with currently available genomes, the highest average nucleotide identity value was 83 % to Halogranum salarium B-1T (GenBank accession no. GCA_000283335.1). These data indicate that this new isolate cannot be classified into any recognized genera of the family Haloferacaceae, and therefore strain SB9T is considered to be a representative of a novel species of a new genus within this family, for which the name Haloprofundus marisrubri gen. nov., sp. nov. is proposed. The type strain of Haloprofundus marisrubri is SB9T (=JCM 19565T=CGMCC 1.14959T).

Roseomonas chloroacetimidivorans sp. nov., a chloroacetamide herbicide-degrading bacterium isolated from activated sludge.

A Gram-negative, aerobic, short rod-shaped, pink-pigmented, non-motile bacterium, designated BUT-13(T), was isolated from activated sludge of an herbicide-manufacturing wastewater treatment facility in Jiangsu province, China. Growth was observed at 0-5.5 % NaCl, pH 6.0-9.0 and 12-37 °C. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain BUT-13(T) is a member of the genus Roseomonas, and shows high sequence similarities to R. pecuniae N75(T) (98.0 %) and R. rosea 173-96(T) (97.5 %), and lower (<97 %) sequence similarities to all other Roseomonas species. Chemotaxonomic analysis revealed that strain BUT-13(T) possesses Q-10 as the predominant ubiquinone; summed feature 8 (C18:1 w7c and/or C18:1 w6c; 38.8 %), C18:0 (16.6 %), C16:0 (15.2 %), summed feature 3 (C16:1 ω6c and/or C16:1 ω7; 7.9 %) and C18:1 w9c (4.7 %) as the major fatty acids. The polar lipids were found to consist of two aminolipids, a glycolipid, a phospholipid, a phosphoglycolipid, phosphatidylcholine, phosphatidylethanolamine and diphosphatidylglycerol. Strain BUT-13(T) showed low DNA-DNA relatedness with R. pecuniae N75(T) (45.2 %) and R. rosea 173-96(T) (51.2 %). The DNA G+C content was determined to be 67.6 mol%. Based on the phylogenetic analysis, DNA-DNA hybridization and chemotaxonomic analysis, as well as biochemical characteristics, strain BUT-13(T) can be clearly distinguished from all currently recognised Roseomonas species and should be classified as a novel species of the genus Roseomonas, for which the name Roseomonas chloroacetimidivorans sp. nov. is proposed. The type strain is BUT-13(T) (CCTCC AB 2015299(T) = JCM 31050(T)).

Sphingomonas chloroacetimidivorans sp. nov., a chloroacetamide herbicide-degrading bacterium isolated from activated sludge.

Strain Y1(T), a Gram-negative, non-spore-forming, rod-shaped bacterium, was isolated from activated sludge. This strain is able to degrade several commonly used chloroacetamide herbicides, such as butachlor, acetochlor and alachlor. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain Y1(T) is a member of the genus Sphingomonas and shows high sequence similarities with S. starnbergensis 382(T) (95.7 %), S. sanxanigenens NX02(T) (95.7 %) and S. haloaromaticamans A175(T) (95.3 %), and shows low (<95 %) sequence similarities to all other Sphingomonas species. Chemotaxonomic analysis revealed that strain Y1(T) possesses Q-10 as the predominant ubiquinone, C14:0 2-OH as the major 2-hydroxy fatty acid and sym-homospermidine as the major polyamine. The main cellular fatty acids of strain Y1(T) were found to be C18:1 ω7c (38.2 %), C16:1 ω6c/C16:1 ω7c (28.5 %), C16: 0 (10.7 %) and C14:0 2-OH (14.3 %). The main polar lipids were determined to be diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipids (SGL1-SGL3), phosphatidyl dimethylethanolamine and aminophospholipid. The DNA G+C content was found to be 66 ± 0.4 mol%. Based on phylogenetic analysis, phenotypic characteristics and chemotaxonomic data, strain Y1(T) is considered to represent a novel species of the genus Sphingomonas, for which the name Sphingomonas chloroacetimidivorans sp. nov. is proposed. The type strain is Y1(T) (=CCTCC AB 2011178(T) = KACC 16607(T)).

[Isolation of microorganisms producing enzyme capable of degrading tobacco straw and nicotine].

OBJECTIVE: The aim of this study was to screen tobacco straw and nicotine degrading microorganism. METHODS: The bacterium was isolated from tobacco field soil using medium containing tobacco straw as the sole carbon and nitrogen source. We identified the bacterium through morphological and physiological characterization combined with the result of 16S rRNA gene sequence and data analysis. We also studied the lignocelluloses degradation and enzyme activities related to the degradation of lignin and cellulose in liquid state fermentation of tobacco stalk. RESULTS: The bacterium was identified as Bacillus megaterium and we had demonstrated that it has a good ability to degrade lignin in tobacco straw when fermented in liquid state. It showed the highest laccase production of 418. 52 U/L while the highest lignin peroxides and manganese peroxides activity was 19. 71 U/L and 64. 71 U/L. On the other hand, we also found that nicotine in tobacco stem was totally degraded 20 d after inoculation. CONCLUSION: to the isolated Bacillus megaterium is capable of degrading tobacco straw partially and nicotine totally.

Roseomonas rhizosphaerae sp. nov., a triazophos-degrading bacterium isolated from soil.

A novel aerobic, non-spore-forming, non-motile, catalase- and oxidase-positive, Gram-stain-negative, coccoid to short-rod-shaped bacterial strain, designated YW11(T), was isolated from soil under long-term application of triazophos. The strain was able to hydrolyse triazophos. Strain YW11(T) grew at 15-40 °C (optimum at 28 °C), at pH 5.0-8.0 (optimum at pH 7.5) and with 0-5.0 % (w/v) NaCl (optimum at 0.5 %). The major respiratory quinone was ubiquinone 10 (Q-10) and the major cellular fatty acids were C18 : 1ω7c, C16 : 0, C18 : 1 2-OH and C18 : 0. The genomic DNA G+C content of strain YW11(T) was 69.6±0.5 mol%. The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylcholine, an unknown glycolipid and two unknown aminolipids. Phylogenetic analysis based on 16S rRNA gene sequence comparison revealed that strain YW11(T) was a member of the genus Roseomonas, and showed the highest sequence similarity to Roseomonas cervicalis KACC 11686(T) (97.9 %) and Roseomonas aestuarii KACC 19645(T) (97.8 %) and then to Roseomonas ludipueritiae KACC 13843(T) (96.9 %). Strain YW11(T) showed low DNA-DNA relatedness with R. cervicalis KACC 11686(T) (32.3±2.9 %), R. aestuarii KACC 16549(T) (28.2±2.6 %) and R. ludipueritiae KACC 13843(T) (30.2±2.6 %). Based on the results of phylogenetic analysis and DNA-DNA hybridization, the whole-cell fatty acid composition as well as biochemical characteristics, strain YW11(T) was clearly distinguished from all recognized species of the genus Roseomonas and should be assigned to a novel species of the genus Roseomonas, for which the name Roseomonas rhizosphaerae sp. nov. is proposed. The type strain is YW11(T) ( = KACC 17225(T) = CCTCC AB2013041(T)).

Fermented Purslane (Portulaca oleracea L.) Supplementation Enhances Growth and Immune Function Parallel to the Regulation of Gut Microbial Butyrate Production in Weaned Piglets.

Weaning is a challenging period for piglets, characterized by stress-related growth checks, compromised immunity, and gut dysbiosis. Purslane (Portulaca oleracea L.), known for its rich content of antioxidants, has potential as a functional feed ingredient. This study investigates the effects of feeding fermented purslane (FP) on the growth performance, immune function, intestinal microbiota, and metabolic profiles of weaned piglets. Forty-eight weaned piglets were randomly divided into two groups, with eight pens in each group and three pigs in each pen: a control diet (CON group) and a diet supplemented with 0.20% FP (FP group). The experiment lasted 28 days. The results show that FP supplementation did not affect the average daily feed intake (ADFI) but significantly increased the average daily gain (ADG) during the initial 14 days post-weaning. FP supplementation decreased diarrhea occurrence, with a pronounced reduction from days 10 to 13 (p < 0.05). Immunologically, the FP group had a trend towards reduced serum IgA levels on day 14 (p < 0.10). Importantly, the serum concentrations of the pro-inflammatory cytokine IL-6 were significantly reduced on both days 14 and 28 post-weaning. The antioxidative analysis showed increased serum superoxide dismutase (SOD) and decreased catalase (CAT) activities on day 14 (p < 0.05). In addition, FP supplementation significantly decreased serum diamine oxidase (DAO) activity and D-lactate levels by day 28, indicating a potential improvement in gut integrity. Fecal microbiota assessment demonstrated a distinctive clustering of microbial communities between the FP and CON groups, with an increase in the abundance of Clostridium_sensu_stricto_1, Tyzzerella, and Prevotellaceae_NK3B31_group and a decrease in Lactobacillus, Bacillus, and Subdoligranulum in the FP group (p < 0.05). Functional predictions suggested that the relative abundance of microbial butyrate synthesis enzymes (EC 2.7.2.7 and EC 2.3.1.19) was significantly enhanced by FP treatment. This modulation was further corroborated by elevated fecal butyrate levels (p < 0.05). In summary, dietary supplementation with FP promotes early-growth performance and has beneficial effects on immune function and intestinal health in weaned piglets. The enhancements may be attributed to distinct microbiota compositional changes and targeted modulation of microbial butyrate metabolism, which are crucial for piglet post-weaning adaptation and overall health.

Enchanced levels of apolipoprotein M during HBV infection feedback suppresses HBV replication.

BACKGROUND: Chronic liver diseases can interfere with hepatic metabolism of lipoproteins, apolipoproteins. Hepatitis B virus (HBV) is a major etiological agent causing acute and chronic liver diseases. Apolipoprotein M (ApoM) is a high-density lipoprotein (HDL) apolipoprotein and exclusively expressed in the liver parenchyma cells and in the tubular cells of the kidney. This study was to determine the correlation between HBV infection and ApoM expression. MATERIALS AND METHODS: Serum ApoM levels in patients with HBV infection and in healthy individuals were measured by ELISA, ApoM mRNA expression were determined by RT-PCR, and the expression of S and E proteins of HBV, as well as the synthesis of viral DNA were measured by ELISA and real-time PCR. RESULTS: The levels of serum ApoM was significantly elevated in patients as compared to healthy individuals (P < 0.001), ApoM promoter activity, mRNA and protein expression were all stimulated in cells transfected with infectious HBV clone. In addition, ApoM decreases the expression of S and E proteins of HBV and the synthesis of viral DNA. CONCLUSION: Raised ApoM levels in HBV infection may in turn suppress HBV replication, one of the protective mechanisms of nature.

Effect of Carbonized Herba schizonepetae on the Bioavailability of Eight Active Components from Pulsatillae Decoction in its Particular Adsorption and Release Performance.

BACKGROUND: Carbonized herbal medicine has been used clinically for centuries in China; however, its influence on the bioavailability of compatible medicinal herbs is still unknown. OBJECTIVES: To explore the effect of a carbonized herbal medicine on the in vivo adsorption and release and absorption of other active pharmaceutical ingredients in a compound prescription. METHODS: The bioavailability of carbonized Herba schizonepetae (CHS) to eight active components (epiberberine, coptisine, palmatine, berberine, phellodendrine, aesculin, aesculetin, and anemoside B4) in the aqueous extract of Pulsatillae Decoction (PDAE) was evaluated by the in vitro adsorption and release and in vivo pharmacokinetics tests. Activated carbon (AC) was used as the control. RESULTS: In vitro experiment showed that the cumulative adsorption rates of CHS to the eight active components were 33.17%, 54.32%, 21.48%, 42.01%, 39.1%, 25.11%, 32.11%, and 23.08% which was characterized by copsitine > berberine > phellodendrine > epiperberine > aesculetin > anemoside B4 > palmatine., and they were significantly lower than those of AC. The stable release concentration in sequence was 3.23, 3.04, 3.32, 7.29, 3.17, 2.80, 1.45, and 3.81 µg/mL, which was characterized by berberine > anemoside B4 > palmatine > epiberberine > phellodendrine > coptisine > aesculin > aesculetin, and they were significantly higher than those of AC. The animal experiment indicated that the areas under the concentration-time curve (AUC0-∞) of epiberberine, berberine, aesculetin, and anemoside B4 in PDAE+CHS group were significantly higher than those in the PDAE and PDAE+AC groups, and the other four components in the PDAE+CHS group were lower than those in PDAE group but higher than those in PDAE+AC group. CONCLUSION: CHS could significantly improve the bioavailability of epiberberine, berberine, aesculetin, and anemoside B4 in Pulsatillae Decoction and has a sustained-release effect on berberine, aesculin, aesculetin, and anemoside B4.

Biochemical characterization of a GH19 chitinase from Streptomyces alfalfae and its applications in crystalline chitin conversion and biocontrol.

Chitinases play crucial roles in enzymatic conversion of chitin and biocontrol of phytopathogenic fungi. Herein, a chitinase of glycoside hydrolase (GH) family 19, SaChiB, was cloned from Streptomyces alfalfae ACCC 40021 and expressed in Escherichia coli BL21(DE3). The purified SaChiB displayed maximal activities at 45 °C and pH 8.0, and showed good stability up to 55 °C and in the range of pH 4.0-11.0, respectively. It exhibited substrate specificity towards chitin and chitooligosaccharides (degree of polymerization 3-6) with the endo-cleavage manner. In combination with the N-acetyl hexosaminidase SaHEX, it yielded a conversion rate of 95.2% from chitin powder to N-acetyl-D-glucosamine in 8 h and a product purity of >98.5%. Furthermore, the enzyme strongly inhibited the growth of tested pathogenic fungi. These results indicated that SaChiB has the great potential for applications in the conversion of raw chitinous waste in industries as well as the biocontrol of fungal diseases in agriculture.

[Cloning, expression and characterization of a new endo-ß-N-acetylglucosaminidase from Streptomyces alfalfae].

Endo-ß-N-acetylglucosaminidase is used widely in the glycobiology studies and industries. In this study, a new endo-ß-N-acetylglucosaminidase, designated as Endo SA, was cloned from Streptomyces alfalfae ACCC 40021 and expressed in Escherichia coli BL21 (DE3). The purified recombinant Endo SA exhibited the maximum activity at 35 ºC and pH 6.0, good thermo/pH stability and high specific activity (1.0×106 U/mg). It displayed deglycosylation activity towards different protein substrates. These good properties make EndoSA a potential tool enzyme and industrial biocatalyst.

Berberine ameliorates CCl4­induced liver injury in rats through regulation of the Nrf2­Keap1­ARE and p53 signaling pathways.

Berberine (BBR) is an isoquinoline alkaloid, reported to have multiple pharmacological functions. However, its effects against CCl4­induced oxidative damage remain poorly studied. Therefore, the present study investigated the protective action of BBR, and its antioxidant mechanisms, against CCl4­induced liver injury in rats. A total of 48 rats were randomly arranged into six groups: Control; model; positive control (PC); BBR low­dose (BL); BBR middle­dose (BM); and BBR high­dose (BH). The BL, BM and BH animals received BBR (5, 10 and 15 mg/kg by weight, respectively) orally for 7 consecutive days. Rats in the PC group were given silymarin (150 mg/kg), and the control and model groups were administered distilled water orally. At the end of the experiment, blood samples and livers were collected. To measure the liver biochemical indices, the reactive oxygen species (ROS) generation and the expression levels of related genes and protein, the following methods were used: An automatic biochemical analyzer; flow cytometry; spectrophotometry; reverse transcription­quantitative PCR; western blotting; and hematoxylin and eosin staining. The results revealed that BBR significantly decreased the serum levels of alanine transaminase, aspartate transaminase and alkaline phosphatase, and increased those of glutathione and superoxide dismutase, but decreased malondialdehyde activity in hepatic tissue, and significantly decreased the reactive oxygen species level in hepatocytes. In hepatic tissue, the expressions of nuclear factor erythroid 2­related factor 2 (Nrf2), kelch­like ECH­associated protein 1 (Keap-1), NAD(P)H quinone dehydrogenase 1 (NQO-1), heme oxygenase 1 (HO­1), Bcl­2 and Bcl­xL mRNA, and HO­1 protein were elevated, and the expression of p53 mRNA was decreased, particularly in the BH group (15 mg/kg). In conclusion, BBR exerts a protective action against CCl4­induced acute liver injury in rats via effectively regulating the expression of Nrf2­Keap1­antioxidant responsive element­related genes and proteins, and inhibiting p53 pathway­mediated hepatocyte apoptosis.

Biochemical characterization of a ß-N-acetylhexosaminidase from Streptomyces alfalfae and its application in the production of N-acetyl-d-glucosamine.

N-Acetyl-d-glucosamine (GlcNAc) is a valuable monosaccharide widely used in the medical, agricultural, biofuel, and food industries. Its efficient and environment-friendly production depends on the binary system of ß-N-acetylhexosaminidase (HEX) and chitinase. In the present study, a HEX of glycoside hydrolasefamily 20 was identified in Streptomyces alfalfae ACCC40021, and was overexpressed in Escherichia coli. The purified recombinant SaHEX showed maximal activities at 60°C and pH 5.5, and retained stable up to 45°C. The enzyme not only exhibited broad substrate specificity including p-nitrophenyl ß-N-acetylglucosaminide, p-nitrophenyl ß-N-acetylgalactosaminide, chitooligosaccharides and colloidal chitin, but also had higher specific activities (up to 1149.7 ± 72.6 U/mg) towards natural and synthetic substrates. When combined with a commercial chitinase, it achieved a conversion rate of 93.7% from 1% of colloidal chitin to GlcNAc in 6 h, with the product purity of >98%. These excellent properties make SaHEX a potential enzyme candidate for the chitin conversion for various industrial purposes.

An alkaline and surfactant-tolerant lipase from Trichoderma lentiforme ACCC30425 with high application potential in the detergent industry.

Alkaline lipases with adaptability to low temperatures and strong surfactant tolerance are favorable for application in the detergent industry. In the present study, a lipase-encoding gene, TllipA, was cloned from Trichoderma lentiforme ACCC30425 and expressed in Pichia pastoris GS115. The purified recombinant TlLipA was found to have optimal activities at 50 °C and pH 9.5 and retain stable over the pH range of 6.0-10.0 and 40 °C and below. When using esters of different lengths as substrates, TlLipA showed preference for the medium length p-nitrophenyl octanoate. In comparison to commercial lipases, TlLipA demonstrated higher tolerance to various surfactants (SDS, Tween 20, and Triton X100) and retained more activities after incubation with Triton X100 for up to 24 h. These favorable characteristics make TlLipA prospective as an additive in the detergent industry.

Rhizoma smilacis glabrae protects rats with gentamicin-induced kidney injury from oxidative stress-induced apoptosis by inhibiting caspase-3 activation.

ETHNOPHARMACOLOGICAL RELEVANCE: Rhizoma smilacis glabrae (RSG), which is mild-natured and tastes sweet or bland, has pharmacological action of eliminating dampness, detoxifying, and ensuring that joints were healthy and supple in traditional Chinese medicine. AIM OF THE STUDY: To discuss the protective effect of RSG on gentamicin (GM)-induced kidney injury in rats and its regulatory mechanisms of oxidative stress-induced apoptosis by inhibiting caspase-3 activation. MATERIALS AND METHODS: A total of 40 Sprague-Dawley (SD) rats were randomly divided into 5 groups: control group, model group, and RSG low, middle, and high dose groups (0.75，1.5，3gkg-1). Six hours after intramuscular GM injections, rats in the model group were given distilled water by intragastric administration, and rats in the 3 RSG intervention groups were given different dosages of RSG water-extracts. Twenty-four hours after the last administration, blood and kidney samples were collected to test for biochemical indexes of kidney injury, oxidative stress, histopathological defects, apoptosis rate, and caspase-3 protein expression to assess the protective effect of RSG water-extracts against GM-induced kidney injury. RESULTS: Compared with the model group, serum TP and ALB levels were significantly higher (P<0.05), and BUN, CRE, and UA levels were significantly lower (P<0.05) in the 3 RSG intervention groups. In kidney tissues, SOD, CAT, and GSH levels increased significantly (P<0.05), while MDA level decreased significantly (P<0.05). Total apoptosis rate dropped markedly (P<0.01), and the protein expressions of caspase-3 increased, while expressions of activated caspase-3 decreased. Histopathological analysis showed shrinkage of kidney cells reduced with appearance of complete kidney structure and decrease in activated caspase-3 expressions in impaired renal tubules decreased. Among the 3 RSG intervention groups, the middle dose group (1.5gkg-1) showed the best protective effect. CONCLUSIONS: RSG water-extracts had protective effects against GM-induced kidney injury in rats, and its mechanism of action was related to oxidative stress-induced apoptosis by inhibiting caspase-3 activation.

[Mechanism linking atherosclerosis and type 2 diabetes: increased expression of scavenger receptor CD36 in monocytes].

BACKGROUND: We investigated the pathogenesis of atherosclerosis in diabetes, and detected the expression of scavenger receptor CD36 in monocytes in patients with type 2 diabetes. METHODS: According to the criteria by WHO, diabetic patients were classified into two groups: well controlled diabetic patients (WCP) and poorly controlled diabetic patients (PCP). The expression of CD36 protein and mRNA were evaluated by flow cytometry and reversal transcription polymerase chain reaction (RT-PCR). Plasma levels of accumulation of oxidized LDL (oxLDL) were directly measured by sandwich enzyme-linked immunosorbent assay (ELISA) method. RESULTS: Flow cytometry and RT-PCR showed that the mean fluorescence intensity (MFI) of CD36 in monocyte and CD36 mRNA were significantly higher in the PCP and WCP in comparison with healthy controls (P<0.01). CD36 MFI and mRNA in the PCP were increased by 78% and 36% compared to the WCP. In both groups, CD36 MFI and mRNA were significantly higher in patients with diabetic atherosclerosis in comparison with those without diabetic atherosclerosis (P<0.05). No significant difference was found in CD14 expression between the groups (P>0.05). The concentrations of plasma oxLDL were higher in the PCP group compared to WCP and control group (P<0.05), whereas oxLDL average values did not differ significantly between WCP and control groups (P>0.05). In the WCP and PCP groups, oxLDL levels were higher in patients with diabetic atherosclerosis than those without diabetic atherosclerosis (P<0.05). CONCLUSIONS: The increased expression of scavenger receptor CD36 may be one of the mechanism of accelerated atherosclerosis in diabetic. The poorly controlled diabetes patients are at higher risk for the vascular complications than the well controlled diabetic patients.

Biodegradation of nicosulfuron by a Talaromyces flavus LZM1.

The fungal strain LZM1 was isolated from activated sludge and found to be capable of utilizing nicosulfuron as the sole nitrogen source for growth. Based on morphological and internal transcribed spacer evaluations, LZM1 was identified as a Talaromyces flavus strain. Under optimum conditions (pH 6.1, 29°C), T. flavus LZM1 degraded 100% of the initially added nicosulfuron (100 mg L(-1)) within 5d. T. flavus LZM1 was also found to be highly efficient in degrading tribenuron methyl, chlorsulfuron, bensulfuron methyl, ethametsulfuron methyl, cinosulfuron, and rimsulfuron. Metabolites from nicosulfuron degradation were identified by liquid chromatography mass spectrometry, and a possible degradation pathway was deduced. These results show that T. flavus LZM1 may possess potential to be used in bioremediation of nicosulfuron-contaminated environments.

[Effects of Trichoderma longbrachitum and Streptomyces jingyangensis combination on the growth and disease resistance of tobacco seedlings].

An agar plate antagonism experiment in combining with in vivo screening experiment was conducted to study the affinity and bacteriostasis spectrum of the combination of biocontrol agents Trichoderma longbrachitum and Streptomyces jingyangensis to Nicotiana tabacum seedlings, with the effects of each agent and their combination on the N. tabacum seedlings growth, induced resistance, and resistance to Phytophthora nicotianae analyzed. The two agents had no interactive inhibitory effect and showed higher affinity to N. tabacum, and the agents themselves as well as their metabolites had higher bacteriostasis activities and wider bacteriostasis spectrum to P. nicotiaonae, Pythium aphanidermatum, and Alternaria alternate in different habitats. The combination of the two agents affected the morphological characteristics of the seedlings underground and aboveground parts, promoted the growth of root, stem, and leaf, and increased the root volume, total surface area, length, and average diameter as well as the stem height and size and the leaf length, width, and biomass, with these promotion effects being superior than those of the single-agent treatment. The combination of the two agents also increased the activities of the defensive enzymes superoxide dismutase, catalase, phenylalanine ammonia lyase, and peroxidase in the seedlings root significantly, with the relative control efficiency against P. nicotianae reached 69.3%, as compared to the conventional treatment. This study showed that the combination of T. longbrachitum and S. jingyangensis was a compatible combination with higher affinity and efficiency. This combination showed a synergistic effect of the two agents in plant disease control and in promoting plant growth, being able to promote the tobacco seedlings growth and control the P. nicotianae effectively.