Isolation, Purification, and Characterization of Fungal Laccase from Pleurotus sp.

Laccases are blue copper oxidases (E.C. 1.10.3.2 benzenediol: oxygen oxidoreductase) that catalyze the one-electron oxidation of phenolics, aromatic amines, and other electron-rich substrates with the concomitant reduction of O2 to H2O. They are currently seen as highly interesting industrial enzymes because of their broad substrate specificity. A positive strain was isolated and characterized as nonspore forming Basidiomycetes Pleurotus sp. Laccase activity was determined using ABTS as substrate. Laccase was purified by ionexchange and gel filtration chromatography. The purified laccase was a monomer showed a molecular mass of 40 ± 1 kDa as estimated by SDS-PAGE and a 72-fold purification with a 22% yield. The optimal pH and temperature were 4.5 and 65°C, respectively. The Km and Vmax values are 250 (mM) and 0.33 (μmol/min), respectively, for ABTS as substrate. Metal ions like CuSO4, BaCl2, MgCl2, FeCl2, ZnCl2 have no effect on purified laccase whereas HgCl2 and MnCl2 moderately decrease enzyme activity. SDS and sodium azide inhibited enzyme activity, whereas Urea, PCMB, DTT, and mercaptoethanol have no effect on enzyme activity. The isolated laccase can be used in development of biosensor for detecting the phenolic compounds from the effluents of paper industries

ANTIMICROBIAL AND ANTIOXIDANT ACTIVITY OF METHANOLIC ROOT EXTRACT OF TABERNAEMONTANA ALTERNIFOLIA L

Objective: The infectious diseases caused by bacteria are a major problem and most of them are resistant to the present antibiotics. Also the free radicals act on structural and functional architecture of the cell in turn lead to cytotoxicity and genotoxicity of the cell. In this regard plants would have molecules alternative to antibiotics with higher safety, efficiency and will play a key role in maintaining human health.Methods: In this study antimicrobial activity of methanolic crude extract of Tabernaemontana alternifolia root extract was determined by an agar gel diffusion method against Bacillus flexus, Pseudomonas aeruginosa, Staphylococcus aureus and Proteus aureus and E. coli bacteria, Aspergillus terreus and Scopulariopsis sp. fungi. Antioxidant potential of root extract was determined by ABTS assay and DPPH method.Results: The methanolic root extracts of T. alternifolia posses significant antibacterial activity and reducing power. The significant inhibition was observed at 250, 500, 750, 1000µg/ml for Bacillus flexus, Proteus aureus bacteria. Staphylococcus aureus was inhibited at 1000µg/ml concentration of the plant extracts. Crude extract inhibited DPPH with IC50 value 250 µg/ml and ABTS with IC50 value 600 µg/ml. No antifungal activity was observed.Conclusion: The overall result can conclude that T. alternifolia root posses marked antibacterial activity and anti oxidant activity at lower concentration of plant extract.Â

Ethnomedicinal plants and isolated compounds against Snake venom activity: A review

491-505Snakebite is an occupational hazard that has affected the population in tropical and subtropical countries. Worldwide approximately 5.4 million bites, 2.7 million envenomations, and 81,000-1,38,000 deaths are observed per annum. The incidences are higher among farmers and plantation workers. Antivenom is the only treatment available and the production of the same is challenging due to geographical variation of snakes, storage conditions, and non-availability of venom for production. Antivenom therapy is associated with immediate or delayed hypersensitivity and does not prevent local tissue damage. Thus the search for medicinal plants by the scientific community has become relevant. The ethnobotanical studies on various plants have revealed their use to treat various ailments including snakebite. Hence, the review is aimed to amass the medicinal plants studied and also emphasize various components isolated that have shown promising results

Ethnomedicinal plants and isolated compounds against Snake venom activity: A review

Snakebite is an occupational hazard that has affected the population in tropical and subtropical countries. Worldwide approximately 5.4 million bites, 2.7 million envenomations, and 81,000-1,38,000 deaths are observed per annum. The incidences are higher among farmers and plantation workers. Antivenom is the only treatment available and the production of the same is challenging due to geographical variation of snakes, storage conditions, and non-availability of venom for production. Antivenom therapy is associated with immediate or delayed hypersensitivity and does not prevent local tissue damage. Thus the search for medicinal plants by the scientific community has become relevant. The ethnobotanical studies on various plants have revealed their use to treat various ailments including snakebite. Hence, the review is aimed to amass the medicinal plants studied and also emphasize various components isolated that have shown promising results

Virtual Sensor Based Feedback Active Noise Control For Neonates in NICU

In this paper, a novel approach based on Feedback Active Noise Control with Virtual sensing has been proposed to reduce the Neonatal Intensive Care Unit (NICU) noise for infants in incubator. In NICU, the noise is due to infant monitoring medical equipments located in the vicinity of incubators. To address this, the algorithms in the literature are based on feedforward approach which requires a good reference to achieve effective attenuation. In an NICU environment, these algorithms require more than one reference microphone, which increases the complexity of the algorithm. This is eliminated by the proposed Feedback Active Noise Control approach as it generates its own reference from the error signal. The baby's ears must fall in the zone of silence (ZOS) to ensure noise reduction at its ears. But the volume of ZOS is inversely proportional to noise frequency and for frequencies above 1 KHz the ZOS is less than an inch. This constraint is overcome by the virtual sensing technique, which focuses the ZOS at baby's ears. The algorithm is evaluated with noise record from Neonatal Intensive Care Unit and it has resulted in 7dB more reduction at the baby’s ears compared to existing algorithms

Biotransformation of Δ3-carene by <i style="mso-bidi-font-style:normal">Penicillium nigricans</i>

217-222A fungus was isolated from forest soil by selective enrichment method with Δ3-carene as a sole source of carbon and identified as Penicillium nigricans. The isolate was capable of transforming Δ3-carene into neutral [dihydrocarvone, carvone, carveol, (+)-trans-p-mentha-5,8-dien-2-ol and (+)-trans-p-mentha-5,8-dien-2-one] and acidic (perillic acid and 2-hydroxy-p-menth-8-ene-7-oic-acid) metabolic compounds. These compounds were identified based on infrared (IR), proton nuclear magnetic resonance (1H NMR) and mass spectrum (MS) studies. Three pathways have been proposed for the transformation of Δ3-carene into the neutral and acid metabolic compounds based on the study of oxygen consumption by Δ3-carene grown fungal cells. As the different metabolic intermediates of Δ3-carene are much used in the perfume industry, the Δ3-carene, which is abundantly available, can be used as a starting material in the perfume industry by microbial techniques, using this fungal strain

Production and Purification of Pectinase from <i>Bacillus subtilis</i> 15A-B92 and Its Biotechnological Applications

Enzymes that degrade pectin are called pectinases. Pectinases of microbial origin are used in juice clarification as the process is cost-effective. This study screened a pectinase-producing bacterium isolated from soil and identified as Bacillus subtilis 15A B-92 based on the 16S rRNA molecular technique. The purified pectinase from the isolate showed 99.6 U/mg specific activity and 11.6-fold purity. The molecular weight of the purified bacterial pectinase was 14.41 ± 1 kD. Optimum pectinase activity was found at pH 4.5 and 50 °C, and the enzyme was 100% stable for 3.5 h in these conditions. No enzymatic inhibition or activation effect was seen with Fe2+, Ca2+, or Mg2+. However, a slight inhibition was seen with Cu2+, Mn2+, and Zn2+. Tween 20 and 80 slightly inhibited the pectinase, whereas iodoacetic acid (IAA), ethylenediaminetetraacetate (EDTA), urea, and sodium dodecyl sulfate (SDS) showed potent inhibition. The bacterial pectinase degraded citrus pectin (100%); however, it was inactive in the presence of galactose. With citrus pectin as the substrate, the Km and Vmax were calculated as 1.72 mg/mL and 1609 U/g, respectively. The high affinity of pectinase for its substrate makes the process cost-effective when utilized in food industries. The obtained pectinase was able to clarify orange and apple juices, justifying its application in the food industry

Evaluation of Anti-Venom Potential of <em>Areca catechu</em> Seed Extract on <em>Bungarus caeruleus</em> Venom

Areca catechu seeds and their extract/s are currently used to treat various ailments and infections including snakebites. The purpose of this investigation was to assess the inhibiting/neutralizing effect of ethyl acetate and aqueous ethanolic seed extracts of A. catechu on Bungarus caeruleus (krait) venom. The enzyme activities and their inhibition were evaluated using standard procedures (in vitro). In vivo studies were conducted using chick embryos and murine models. The extracts inhibited hyaluronidase and phospholipase A2 activities. Protease activity was neutralized by the aqueous ethanolic extract only. The IC50 value of aqueous ethanolic extract for hyaluronidase was 0.001 g/mL, while that for the ethyl acetate extract for phospholipase A2 was 0.006 g/mL. In addition, both the extracts neutralized the indirect hemolysis and fibrinogenolytic activity induced by B. caeruleus venom. The LD50 for the chick embryos was 4.9 µg/egg. The 50 and 100 µg aqueous ethanolic extracts neutralized the LD50 and the challenging dose (3LD50) of venom effectively in the chick embryo model. The LD50 of B. caeruleus venom in mice was 0.1927 µg/kg; the extract extended the survival time of the mice from 25 min to 30 and 35 min in 1:10 and 1:20 ((w/w) venom:extract) ratios, respectively. The extract also neutralized myotoxic activity. The A. catechu seed extract showed promising inhibitory properties against B. caeruleus venom. In this regard, academia and industries should work collaboratively to develop and formulate a cost-effective first-aid drug