ABSTRACT
In this investigation an attempt has been made to characterize and identify Lysinibacillus sp. 3HHX by 16S-rDNA sequencing. The bacterium exhibited occurrence of PHAs granules on an average 11±1 per cell of 1.0µm length and breadth 0.72µm, revealed from TEM studies. Under optimized condition, 4.006gm/L of PHAs was extracted using hypochlorite digestion and multi-solvent extraction process. PhaC gene of â¼540bp and higher PHA synthase activity was detected at 48h of cultivation. The extracted PHAs was structurally characterized by GC-MS and 1H NMR reported to be P(3HB-co-3HDD-co-3HTD) and amorphous in nature with 112°C melting point, -11.0°C glass transition point and 114.76°C decomposition temperature detected by DSC & TGA respectively. The C/O of biopolymer disc was 1:65 as revealed from C1s and O1s spectra of XPS, that was completely biodegradable within 30 days. This biopolymer was observed to be non-cytotoxic to NIH 3T3 mouse fibroblast cells. The report is of its kind in establishing the abilities of Lysinibacillus sp. 3HHX for non-growth associated PHA co-polymer production. Moreover the biocompatible and biodegradable nature of the biopolymer conferred to its substantial biomedical applications.
Subject(s)
Bacillaceae/metabolism , Fermentation , Polyhydroxyalkanoates/biosynthesis , Polyhydroxyalkanoates/chemistry , Animals , Cell Survival/drug effects , Immersion , Mice , NIH 3T3 Cells , Polyhydroxyalkanoates/metabolism , Polyhydroxyalkanoates/toxicity , Rhizosphere , Soil MicrobiologyABSTRACT
In the present investigation, anti-Candida activity of four essential oils i.e. Black cumin (Nigella sativa), Curry leaf (Murraya koienigii), Ajwain (Trachiyspirum ammi), and Betel leaf (Piper betel) were screened against four human pathogenic species of Candida viz. Candida albicans, Candida tropicalis, Candida glabrata, and Candida parapsilosis. The minimum inhibitory concentration (MIC) values of the oils ranged between 15.62 and 250 µl/ml while studied through tube dilution method. The oils retained their anti-Candida activities even after heat treatment (at 45ÎC, 60ÎC, 100ÎC for 1 hour) and also on autoclaving. Both Ajwain and Black Cumin leaf oils showed better anti-Candida activity against Candida albicans, resulting in an irreversible damage to the cells. The anti-Candida activity of these essential oils could be attributable to the membrane inhibition mechanism. The activity of the oils is reported to be microbicidal (Candida-cidal).
Subject(s)
Candida/drug effects , Microbial Sensitivity Tests , Oils, Volatile/pharmacology , Antifungal Agents/pharmacology , Humans , Plant Oils/pharmacology , TemperatureABSTRACT
The antibacterial activity of Jasmine (Jasminum sambac L.) flower hydro steam distilled essential oil, synthetic blends and six major individual components was assessed against Escherichia coli (MTCC-443) strain. The activity was bactericidal. Minimum inhibitory concentration was determined by tube dilution technique, and the Minimum inhibitory concentration ranged between 1.9-31.25 mul/ml. Phenolcoefficient of the oil, synthetic blends and components varied between 0.6-1.7. The activity of the chemicals was possibly due to the inhibition of cell membrane synthesis.
ABSTRACT
The antibacterial activity of Karanj (Pongamia pinnata) and Neem (Azadirachta indica) seed oil in vitro against fourteen strains of pathogenic bacteria was assessed. Using the tube dilution technique, it was observed that 57.14 and 21.42% of the pathogens were inhibited at 500 microl/ml; 14.28 and 71.42% at 125 microl/ml; and 28.57 and 7.14% at 250 microl/ml of Karanj and Neem oils, respectively. The activity with both the oils was bactericidal and independent of temperature and energy. Most of the pathogens were killed more rapidly at 4 degrees C than 37 degrees C. The activity was mainly due to the inhibition of cell-membrane synthesis in the bacteria.
Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Derris/chemistry , Glycerides/pharmacology , Meliaceae/chemistry , Plant Oils/pharmacology , Terpenes/pharmacology , Bacteria/growth & development , Microbial Sensitivity Tests , Plants, Medicinal/chemistry , Seeds/chemistry , Temperature , Time FactorsABSTRACT
Thermotolerant bacteria (35 in toto) isolated from three hot springs (Atri, Taptapani and Deuljhari, Orissa), were screened for lipase activities. Of these, nine strains of Bacillus spp. and three strains of Pseudomonas spp. showed heat stable lipase activity at 60 degrees C. The hydrolytic activity of these bacteria was tested using Tween-20 and Tween-80 as substrates at different temperatures using plate assay and titration techniques. The hydrolytic activity at different pH values and salt concentrations was investigated.
Subject(s)
Bacillus/enzymology , Lipase/metabolism , Pseudomonas/enzymology , Staphylococcus/enzymology , Water Microbiology , Enzyme Stability , Fresh Water , Heating , IndiaABSTRACT
The four essential oils (aromatic plant products) from palmarosa (Pm), lemongrass (Lg), peppermint (Pt) and eucalyptus (Eu) plants were found to be bactericidal to Escherichia coli strain SP-11, at a concentration of 1.66 (Pm, Lg and Eu) or 2.5 (Pt) microl ml-1. This effect was observed both at 37 degrees C and 4 degrees C and was not prevented by immediate tenfold dilution or by the presence of 0.5 M sucrose. Pm and Pt but not Lg or Eu induced the formation of elongated filamentous forms, some measuring 60-70 micrometers long.
Subject(s)
Escherichia coli/drug effects , Oils, Volatile/pharmacology , Escherichia coli/physiologyABSTRACT
A Curvularia species was isolated from a chronic ulcer on the lower limb of a 21-year-old man. The histopathological findings supported the mycological diagnosis. An enzyme-linked immunosorbent assay (ELISA) was performed using a crude soluble fungal antigen. The patient's serum contained significantly more antibodies than 10 sera from control subjects (P < 0.05, t-test).