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1.
The keratinase degrade highly rigid, cross linked structural polypeptides with different efficiency depending on the type of source. Two newly isolated strains of Bacillus subtilis (RSE163 and RSE165; NCBI Accession no JQ887983 and JQ887982) were found to be efficient keratinase producers with unusual catalytic activity result in different morphological changes in degradation pattern of feather, confirmed by their scanned electron micrographs. Maximum keratinolytic activity of both the strains B. subtilis RSE163 and RSE165 were found to be 366 ± 15.79 and 194 ± 7.26 U after 72 h of incubation. While the disulphide reductase activity of RSE163 and RSE165 estimated 0.24 ± 0.05 and 0.15 ± 0.03 U/ml of enzyme after 24 h of incubation. A total of 16 free amino acids of variable concentration were also analyzed in the cell free supernatant of hydrolyzed feather from two strains. Present study demonstrates the action of two different keratinases in feather degradation.

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2.
Indigenous formulations based on cow dung fermentation are commonly used in organic farming. Three biodynamic preparations viz., Panchagavya (PG), BD500 and ‘Cow pat pit’ (CPP) showed high counts of lactobacilli (109 ml−1) and yeasts (104 ml−1). Actinomycetes were present only in CPP (104 ml−1) and absent in the other two. Seven bacterial isolates from these ferments were identified by a polyphasic approach: Bacillus safensis (PG1), Bacillus cereus (PG2, PG4 PG5), Bacillus subtilis (BD2) Lysinibacillus xylanilyticus (BD3) and Bacillus licheniformis (CPP1). This is the first report of L. xylanilyticus and B. licheniformis in biodynamic preparations. Only three carbon sources—dextrose, sucrose and trehalose out of 21 tested were utilized by all the bacteria. None could utilize arabinose, dulcitol, galactose, inositol, inulin, melibiose, raffinose, rhamnose and sorbitol. All the strains produced indole acetic acid (1.8–3.7 μg ml−1 culture filtrate) and ammonia. None could fix nitrogen; but all except B. safensis and B. licheniformis could solubilize phosphorous from insoluble tri-calcium phosphate. All the strains except L. xylaniliticus exhibited antagonism to the plant pathogen Rhizoctonia bataticola whereas none could inhibit Sclerotium rolfsi. In green house experiment in soil microcosms, bacterial inoculation significantly promoted growth of maize; plant dry weight increased by ~21 % due to inoculation with B. cereus (PG2). Results provide a basis for understanding the beneficial effects of biodynamic preparations and industrial deployment of the strains.

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3.
In this study was conducted the in vitro antimicrobial, antibiofilm, antioxidant, antigenotoxic and anticancer activities investigations on the moss Bryum capillare Hedw (BC). Antimicrobial and antibiofilm activity were tested by MIC and microplate biofilm methods on antibiotic resistant bacteria. While the antioxidant activity of the extract was evaluated by DPPH, metal chelating, plasma lipid peroxidation and total phenolic content, the antigenotoxicity and cytotoxicity were established by Comet test and the WST-1 Cell proliferation assay kit respectively. The MIC values were found to be ≥ 125 µg.mL−1 and a biofilm inhibition of 3–5% against only S. epidermidis was observed. Total phenolic compounds were determined as 23.26 mg/g. The results of DPPH assay, chelating and plasma lipid peroxidation activity were found to be 15%, 3% and 4% respectively. The extract was observed to decrease the affect of H2O2 that cause DNA damage. The BC was also determined 60 ± 5% anticancer activity against SKBR 3 and 76 ± 5% anticancer activity against HeLa cells, where this concentration had only 18 ± 5% cytotoxicity against MCF-12A cells. Also, these results have indicated the potential of Bryum capillare for the first time in novel natural compounds search.  相似文献   

4.
The present experiment was designed to isolate bacterial strains from the brick kiln soil and to check the activity and enzyme kinetics of amylase from these isolates. The bacterial colonies were isolated from soil samples through the serial dilution method. The bacterial isolates were identified through morphological, electron microscopic and molecular analysis. The 16S ribosomal RNA sequences of the isolates IR-1, IR-2, IR-3, IR-8, and IR-9 showed high similarities with Bacillus tequilensis, Bacillus paramycoides, Proteus alimentorum, Bacillus wiedmannii, and Pseudomonas aeruginosa, respectively. All of the bacterial isolates showed a positive catalase activity except IR-9. Furthermore, the isolates showed variable antagonistic effects against different bacterial pathogens. All of the strains produced indole acetic acid (IAA), and the concentrations increased in the presence of tryptophan application. The isolates showed the amylase enzyme activity and maximum activity of isolates was achieved in 4% starch concentration. The IR-9 isolate showed the highest amylase activity of 5.9 U/ml. The Vmax values of the extracellular amylase from different bacterial isolates ranged between 12.90 and 50.00 IU ml−1. The lowest Km value of 6.33 mg starch was recorded for IR-8 and the maximum Kcat value of 2.50 min−1 was observed for IR-3. The amylase activity of the isolates was significantly affected by a range of different incubation time, temperature, and pH values. Further tests are required before the potential utilization of these isolates for amylase production, and in the biopesticide and biofertilizer applications.  相似文献   

5.
Xanthine oxidase is an important enzyme of purine metabolism that catalyzes the hydroxylation of hypoxanthine to xanthine and then xanthine to uric acid. A thermostable xanthine oxidase is being reported from a thermophilic organism RL-2d isolated from the Manikaran (Kullu) hot spring of Himachal Pradesh (India). Based on the morphology, physiological tests, and 16S rDNA gene sequence, RL-2d was identified as Bacillus pumilus. Optimization of physiochemical parameters resulted into 4.1-fold increase in the xanthine oxidase activity from 0.051 U/mg dcw (dry cell weight) to 0.209 U/mg dcw. The xanthine oxidase of B. pumilus RL-2d has exhibited very good thermostability and its t1/2 at 70 and 80 °C were 5 and 1 h, respectively. Activity of this enzyme was strongly inhibited by Hg2+, Ag+ and allopurinol. The investigation showed that B. pumilus RL-2d exhibited highest xanthine oxidase activity and remarkable thermostability among the other xanthine oxidases reported so far.  相似文献   

6.
Two hundred and thirty-two bacterial strains were isolated from the rhizospheric soil of Populus euphratica which is the dominant tree living in extreme arid regions in northwest China. Some strains with plant growth-promoting bacteria related metabolic characteristics were able to promote drought resistance in plants after inoculation. Ten strains with the greatest effects increased the dry weight of wheat shoots from 0.5 to 34.4 %, and the surface area of the root systems from 12.56 to 212.17 % compared to the control after drought treatment whereas no obvious promoting effect was observed in normal water conditions. These 10 strains were identified to be of the genera Pseudomonas, Bacillus, Stenotrophomonas and Serratia by 16S rRNA (rrs) gene sequence alignment. Among these strains, Serratia sp. 1-9 and Pseudomonas sp. 5-23 were the two most effective strains. Both of them produced auxin and the production increased significantly when cultured under simulated drought conditions which are inferred to be the most plausible mechanism for their plant growth-promoting effect under drought stress.

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7.
Streptococcus pyogenes is the frequent cause of purulent infections in humans. Formation of a biofilm is one of the important aspects of its pathogenicity. Streptococcus pyogenes biofilm communities tend to exhibit significant tolerance to antimicrobial challenge during infections. Exploring novel targets against biofilm-forming pathogens is therefore an important alternative treatment measure. We attempted to screen marine bacteria, especially coral-associated bacteria (CAB), for antibiofilm activity against streptococcal biofilm formation. The bacterial biofilms were quantified by crystal violet staining. Of 43 CAB isolates, nine clearly demonstrated antibiofilm activity. At biofilm inhibitory concentrations (BIC), biofilm formation was reduced up to 80%, and sub-BIC (0.5 and 0.25 BIC) significantly reduced biofilm formation by up to 60% and 40–60%, respectively. Extracts of Bacillus horikoshii (E6) displayed efficient antibiofilm activity. As quorum sensing (QS) and cell surface hydrophobicity (CSH) are crucial factors for biofilm formation in S. pyogenes , the CAB were further screened for QS inhibition properties and CSH reduction properties. This study reveals the antibiofilm and QS inhibition property of CAB.  相似文献   

8.
Microbial diversity was assessed in the soils of non-polluted rice fields of Central Rice Research Institute and Choudwar, and textile effluent contaminated (about 30 years) rice fields of Choudwar about 4 years after cessation of pollution. The soils contained 0.62–1.01 % organic C and 0.07–0.12 % total N, and measured 6.18–8.24 pH and 0.6–2.68 mS/cm Eh which were more in the polluted Choudwar soil. The microbial populations (×106 cfu/g soil) in the soils were: heterotrophs 1.21–10.9, spore formers 0.9–2.43, Gram (−)ve bacteria 4.11–8.0, nitrifiers 0.72–1.5, denitrifiers 0.72–2.43, phosphate solubilizers 0.14–0.9, asymbiotic nitrogen fixers 0.34–0.59, actinomycetes 0.07–0.11, fungi 0–0.5 and Bacillus thuringiensis (Bt) 0.4–0.61 which predominated in the polluted soil of Choudwar. The fungi were scarce in the polluted rice fields. The Bt isolates belonged to three motile and one non-motile group. Two motile Bt isolates were phenotyped as Bt subsp. sotto and israelensis, whereas, the non-motile isolate was Bt subsp. wahuensis. All Bt isolates produced extracellular protease, lipase and amylase enzymes. The microbial guilds had positive correlation among themselves, as well as, with soil physico-chemical characters but the fungi had negative relation and the nitrogen fixers were unrelated with the biotic and abiotic components.  相似文献   

9.
Dietary polyunsaturated fatty acids (PUFAs) can be converted to prostaglandins and leukotrienes. Oxygenation of omega-6 PUFAs generally results in the production of pro-inflammatory mediators, whereas oxygenated products of omega-3 (n-3) PUFAs generally have lower inflammatory activity. We hypothesize that elevated n-3 PUFA intakes from fish are associated with lower risk of colorectal cancer among those with genetic variants that result in higher levels of pro-inflammatory mediators. In population-based case–control studies of colon (case n = 1,574) and rectal cancer (case n = 791) and disease-free controls (n = 2,969), we investigated interactions between dietary fatty acid intake and 107 candidate polymorphisms and tagSNPs in PTGS1, PTGS2, ALOX12, ALOX5, ALOX15, and FLAP. The two studies used an identical genotyping protocol. We observed interactions and statistically significant increases in colon cancer risk for low docosahexaenoic acid intake among those with the PTGS1 rs10306110 (−1,053 A > G) variant genotypes (OR = 1.6, 95 % confidence interval = 1.1–2.3, adj. p = 0.06) and rectal cancer risk for low total fat intake among those with the variant PTGS1 rs10306122 (7,135 A > G) (ORvs.wt = 1.80, 1.02–2.99; adj. p = 0.08). The ALOX15 rs11568131 (10,339 C > T) wild type in combination with a high inflammation score (low EPA intake, high AA intake, no regular NSAID use, high BMI, smoking) was associated with increased colon cancer risk (OR = 2.28, 1.7–3.07). Rectal cancer risk was inversely associated with a low inflammation score among PTGS2 rs4648276 (3,934 T > C) variant allele carriers (OR = 0.49, 0.25–0.75). Overall, these data provide some modest evidence for interactions between dietary fat intake and genetic variation in genes involved in eicosanoid metabolism and colorectal cancer risk.

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10.
Sweet sorghum juice was a cheap and renewable resource, and also a potential carbon source for the fermentation production of lactic acid (LA) by a lactic acid bacterium. One newly isolated strain Lactobacillus salivarius CGMCC 7.75 showed the ability to produce the highest yield and optical purity of LA from sweet sorghum juice. Studies of feeding different concentrations of sweet sorghum juice and nitrogen source suggested the optimal concentrations of fermentation were 325 ml l−1 and 20 g l−1, respectively. This combination produced 142.49 g l−1 LA with a productivity level of 0.90 g of LA per gram of sugars consumed. The results indicated the high LA concentration achieved using L. salivarius CGMCC 7.75 not only gives cheap industrial product, but also broaden the application of sweet sorghum.

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The online version of this article (doi:10.1007/s12088-013-0377-0) contains supplementary material, which is available to authorized users.  相似文献   

11.
The present study investigated the antimicrobial and antibiofilm potential of biosurfactants derived from Lactobacillus fermentum Lf1, L. fermentum LbS4 and Lactobacillus plantarum A5 against clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA). The cell wall-bound and intracellular biosurfactants were extracted by solvent extraction method. Fourier-transform infrared spectroscopy-based characterization of biosurfactants revealed the heterogeneous chemical composition involving proteins, fatty acids and carbohydrate moieties in LbS4 and A5, while only the sugar and lipid fractions in Lf1. Fatty acid profiling using Gas chromatography-mass spectrometry indicated hexadecanoic acid and stearic acid as the predominant fatty acids in the biosurfactants of all these strains. Biosurfactants demonstrated dose-dependent antibacterial action against MRSA isolates with the highest inhibition zone diameter (30·0 ± 0·0 to 35·0 ± 0·0 mm) recorded at 400 mg ml−1. Biosurfactants showed an excellent staphylococcal antibiofilm activity by preventing the biofilm formation and disrupting the preformed biofilms. Visual inspection through scanning electron microscopy witnessed the biosurfactants-induced alteration in the cell membrane integrity and subsequent membrane pore formation on staphylococcal cells. Taken together, our findings emphasize the prospects of biomedical applications of biosurfactants as bactericidal and biofilm controlling agents to confront staphylococcal nosocomial infections.  相似文献   

12.
The anti-inflammatory potential of eight indigenous probiotic Lactobacillus isolates was evaluated in vitro in terms of modulating the expression of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) in human acute monocytic leukemia (THP-1) cells under inflammatory conditions. Amongst these, Lactobacillus plantarum Lp91 was the most potent anti-inflammatory strain as it evoked a significant (P < 0.001) down-regulation of TNF-α by −1.45-fold relative to the control in THP-1 cells. However, in terms of IL-6 expression, all the strains could up-regulate its expression considerably at different levels. Hence, based on in vitro expression of TNF-α, Lp91 was selected for in vivo study in lipopolysaccharide (LPS)-induced mouse model to look at the expression of TNF-α, IL-6, monocyte chemotactic protein-1 (MCP-1), vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule (ICAM-1) and E-selectin in mouse aorta. In LPS challenged (2 h) mice group fed with Lp91 for 10 days, TNF-α, IL-6, MCP-1, VCAM-1, ICAM-1 and E-selectin expressions were significantly down-regulated by 3.10-, 10.02-, 4.22-, −3.14-, 2.28- and 5.71-fold relative to control conditions. In conclusion, Lp91 could serve as a candidate probiotic strain to explore it as a possible biotherapeutic anti-inflammatory agent against inflammatory diseases including cardiovascular disease.

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13.
Extracellular glucoamylase of Colletotrichum sp. KCP1 produced through solid state fermentation was purified by two steps purification process comprising ammonium sulphate precipitation followed by gel permeation chromatography (GPC). The Recovery of glucoamylase after GPC was 50.40 % with 19.3-fold increase in specific activity. The molecular weight of enzyme was found to be 162.18 kDa by native-PAGE and was dimeric protein of two sub-units with molecular weight of 94.62 and 67.60 kDa as determined by SDS-PAGE. Activation energy for starch hydrolysis was 26.45 kJ mol−1 while temperature quotient (Q10) was found to be 1.9. The enzyme was found to be stable over wide pH range and thermally stable at 40–50 °C up to 120 min while exhibited maximum activity at 50 °C with pH 5.0. The pKa1 and pKa2 of ionisable groups of active site controlling Vmax were 3.5 and 6.8, respectively. Vmax, Km and Kcat for starch hydrolysis were found to be 58.82 U ml−1, 1.17 mg (starch) ml−1 and 449 s−1, respectively. Activation energy for irreversible inactivation (Ea(d)) of glucoamylase was 74.85 kJ mol−1. Thermodynamic parameters of irreversible inactivation of glucoamylase and starch hydrolysis were also determined.  相似文献   

14.
Metabolites of azo dyes are often carcinogenic, teratogenic, mutagenic and recalcitrant in nature. In this study, four biofilm consortia such as C1 (Vitreoscilla sp. ENSG301, Acinetobacter lwoffii ENSG302, Klebsiella pneumoniae ENSG303 and Pseudomonas fluorescens ENSG304), C2 (Escherichia coli ENSD101, Enterobacter asburiae ENSD102 and E. ludwigii ENSH201), C3 (E. asburiae ENSD102, Vitreoscilla sp. ENSG301 and Bacillus thuringiensis ENSW401), and C4 (E. coli ENSD101, E. ludwigii ENSH201 and B. thuringiensis ENSW401) were applied to degrade and detoxify methyl orange (MO), a carcinogenic, sulfonated mono azo dye, used in textile dyeing industry worldwide. The consortia of C1, C2, C3 and C4 showed 97.30, 98.75, 99.51 and 99.29% decolorization, respectively in yeast extract peptone (YEP) broth containing 200 mg L−1 MO within 60 h of incubation in static condition. The optimum pH and temperature for decolorization was 7.0 and 28 °C, respectively. Some divalent metal ions including Mg2+, Ca2+, Zn2+ and Mn2+ could stimulate MO decolorization. UV–Vis spectral analysis showed that the absorption peak at 465 nm originated from the azo (N Created by potrace 1.16, written by Peter Selinger 2001-2019 N) bond was completely disappeared within 60 h of incubation. Fourier transform infrared spectroscopy (FTIR) results also revealed that several major peaks including azo bond peak at 1602.6 cm−1 are completely or partly vanished, deformed or shifted. Activities of azoreductase, NADH-DCIP reductase and laccase were significantly increased in the bacterial cells within 60 h of incubation in comparison to that of control (0 h). The chemical oxygen demand was incredibly reduced by 85.37 to 91.44% by these consortia. Accordingly, plant (wheat seed germination) and microbial (growth of the plant probiotic bacteria such as Pseudomonas cedrina ESR12 and Bacillus cereus ESD3 on biodegraded products) toxicity studies showed that biodegraded products of MO are non-toxic. Thus, all these consortia can be utilized in bioremediation of MO from wastewater for safe disposal into environment. To our knowledge, this is the first report on degradation and detoxification of MO from wastewater by bacterial biofilm consortia.  相似文献   

15.
Fifty-eight typical EAEC isolates from children with diarrhoea were examined for HEp-2 cell adherence assay, presence of dispersin (aap), yersiniabactin (irp2), plasmid encoded toxins (pet), Shigella enterotoxin1 (set1A) and cryptic open reading frame (shf) putative virulence genes by polymerase chain reaction as well as for biofilm production. All the isolates showed aggregative adherence pattern on HEp-2 cells. All but five isolates (91.3 %) carried aap gene. While irp2, pet, set1A and shf genes were detected in 68.9, 5.1, 39.6, and 60.3 % isolates, respectively. Thirty-three (64.7 %) isolates out of 51 tested were found to produce biofilm which was found to be significantly associated only with set1A virulence gene (P = 0.025). Highest amount of biofilm was produced by a strain that possessed all the genes studied. Out of 14 isolates in which the most frequent gene combination (aap, irp2 and shf) was observed, only six produced biofilm. It is concluded that there is significant heterogeneity in putative virulence genes of EAEC isolates from diarrhoeic children and biofilm formation is associated with multiple genes.  相似文献   

16.
Present article depicts microbiology of starter (Balma) used in traditional solid-state fermentation of alcoholic beverage (Chhang) by Bhotiya tribe of Uttarakhand. It also highlights the importance of herbs in Balma preparation and kinetics of lactic acid and ethanol fermentation under Chhang preparation using Balma. Balma contains 214 × 106 cfu/g yeasts, 2.54 × 106 cfu/g lactic acid bacteria (LAB) and 1.4 × 106 cfu/g other mesophilic bacteria. ITS sequence analysis revealed a rich diversity of yeast comprising of Saccharomyces cerevisiae, Saccharomycopsis fibuligera and Saccharomycopsis malanga in Balma. 16S rDNA sequence analysis revealed Lactobacillus pentosus and Pediococcus pentosaceus among LAB, while amylolytic Bacillus subtilis and B. aerophilus among other bacteria in Balma. Based on the results, it is speculated that herbs such as Inula cuspidata, Micromeria biflora, Origanum vulgare, Rubus sp. and Thymus linearis used earlier by Bhotiya in Balma preparation contribute as a source of yeasts, LAB and amylolytic bacilli. Study also demonstrates that Bhotiya tribe is rational in preparation of starter as they have circumvented the need of plants by using previous year Balma as inoculum and possibility of deficient quality of Balma due to weak colonization of phyllosphere and rhizosphere microbiota. Results suggest that simultaneous saccharification and lactic acid–ethanol fermentation take place in traditional cereal based Chhang fermentation system of Bhotiya.  相似文献   

17.
Ammonia oxidation is the rate limiting step in nitrification and thus have an important role in removal of ammonia in natural and engineered systems with participation of both ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB). However, their relative distribution and activity in fish processing effluent treatment plants (FPETPs) though significant, is hitherto unreported. Presence of AOA in sludge samples obtained from FPETPs was studied by amplification and sequencing of thaumarchaeal ammonia monooxygenase subunit A (AOA-amoA) gene. Different primer sets targeting 16S rRNA and AOA-amoA gene were used for the detection of AOA in FPETPs. Phylogenetic analysis of the gene revealed that the AOA was affiliated with thaumarchaeal group 1.1a lineage (marine cluster). Quantitative real time PCR of amoA gene was used to study the copy number of AOA and AOB in FPETPs. The AOA-amoA and AOB-amoA gene copy numbers of sludge samples ranged from 2.2 × 106 to 4.2 × 108 and 1.1 × 107 to 8.5 × 108 mg−1 sludge respectively. Primer sets Arch-amoAF/Arch-amoAR and 340F/1000R were found to be useful for the sensitive detection of AOA-amoA and Archaeal 16S rRNA genes respectively in FPETPs. Their presence suggests the widespread occurrence and possible usefulness in removing ammonia from FPETPs which is in line with reports from other waste water treatment plants.

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18.
In the present study we investigated whether single nucleotide polymorphisms (SNPs) in the P2RX4, which alter the P2X4R function, are associated with the development of osteoporosis and whether an interaction between the P2X4R and P2X7R confer a synergistic effect of these two receptors on osteoporosis risk. Patients with fracture (690 females and 231 males, aged ≥50 years) were genotyped for three non-synonymous P2X4R SNPs. Bone mineral density (BMD) was measured at the total hip, lumbar spine, and femoral neck. Subject carrying the variant allele of the Tyr315Cys polymorphism showed a 2.68-fold (95 % CI, 1.20–6.02) higher risk of osteoporosis compared with wild-type subject. Furthermore, significant lower lumbar spine BMD values were observed in subjects carrying the Cys315 allele as compared with wild-type (0.85 ± 0.17 and 0.93 ± 0.17 g/cm2, respectively; p < 0.001). Assuming a recessive model, carriers of the variant allele of the Ser242Gly polymorphism showed increased BMD values at the lumbar spine compare to wild-type subject (1.11 ± 0.35 and 0.92 ± 0.17 g/cm2, respectively; p = 0.0045). This is the first study demonstrating an association of non-synonymous polymorphisms in the P2RX4 and the risk of osteoporosis, suggesting a role of the P2X4R in the regulation of bone mass.

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19.

Abstract

Solanum torvum Swartz. (Solanaceae) fruit is traditionally used for the treatment of bacterial and fungal infections. The methanolic extract was subjected to activity guided fractionation by column chromatography over silica gel. The structure of the compound was elucidated using physical and spectroscopic data. The antimicrobial activity was screened using five Gram-positive bacteria, six Gram-negative bacteria, seven clinical isolates and four fungi. Antimycobacterial activity was screened against two Mycobacterium strains. The zone of inhibition by methyl caffeate ranged from 0 to 22 mm. The lowest minimum inhibitory concentration (MIC) values of methyl caffeate were: 50 μg/ml against P. vulgaris, 25 μg/ml against K. pneumoniae (ESBL-3971), 8 μg/ml against M. tuberculosis (H37Rv) and 8 μg/ml against M. tuberculosis (RifR). Methyl caffeate showed moderate antimicrobial and prominent antimycobacterial activities. Methyl caffeate can be evaluated further for drug development.  相似文献   

20.
Novel Bacillus thuringiensis isolates GS4, GN24 and UP1 were isolated and characterized by determination of serotyping, insecticidal protein by SDS-PAGE, plasmid composition, cry gene content and insect toxicity. Serologically two isolates GS4 and UP1 were allocated to the H3abce which is a new serovar while isolate GN24 was of H3ab type. Isolate GS4 produced flat crystal inclusions while UP1 produced cuboidal crystals. PCR analysis found that both isolates contained cry1 and cry1Ac genes. The major protein bands found of isolate GS4 were of molecular weights 175, 135, 97, 88, 66, 54 and 27 kDa, isolate UP1 were of 85, 60 and 40 kDa and isolate GN24 were of 130, 90, 66 and 45 kDa. Though isolates GS4 and UP1 belonged to a new serovar H3abce, they showed different crystal inclusions and cry gene content. Isolate GS4 was toxic to lepidopteran insect larvae of Helicoverpa armigera but UP1 did not showed any toxicity.  相似文献   

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