Identification of efficient dye decolorizing laccase producing fungi from Kolli Hills

33-43Laccase is one of the most promising ligninolytic enzymes for the industrial application and ecofriendly bioremediation process. Twenty-five carpophores were collected from different places of Kolli Hills (Namakkal district Tamilnadu, India) and screened on the solid media containing guaiacol, which enabled the detection of laccase secretion. Three positive strains were isolated and the quantitative production of laccase was determined in submerged culture to select hypersecretory strain for further study. Among the three strains, “ST02” the best producer of laccase was selected and was analyzed for the dye decolorization potential using dyes like Poly R-478 and Remazol Brilliant Blue R (RBBR). Identification of the isolated organism was carried out by classical and molecular methods. Approximately 625 bp of the ST02 5.8S rDNA was amplified by polymerase chain reaction (PCR). The phylogenetic relationship of the isolated strain was studied by comparing the internal transcribed spacer (ITS) sequences of ST02 with similar related sequences deposited in the GenBank database. The present study showed that relatively simple plate test screening method and ITS analysis can be used for identification of laccase producing new strain. The isolated organism was designated as Pleurotus ostreatus IMI 395545

Exploring bioactive fraction of Sargassum wightii: In vitro elucidation of angiotensin-I-converting enzyme inhibition and antioxidant potential

Bioactive fraction of brown algae Sargassum wightii (SWE) was obtained using silica column chromatography and preparative Thin Layer Chromatography (TLC). FT-IR and LC–mass spectrometry ESI analysis revealed presence of various phlorotannins in the SWE. The IC50 value of SWE was found to be 59.91, 51.04, and 55.21 μg/ml for scavenging of 2,2-diphenyl-1-picrylhydrazyl, 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid), and Ferric Reducing Antioxidant Power assay, respectively. SWE inhibited angiotensin-I-converting enzyme (ACE) in mixed-type manner with IC50 value of 56.96 µg/ml and Ki value of 45 µg/ml. The dual function such as antioxidant and ACE inhibition of SWE warrants further study to understand the antihypertensive potential in vivo

Identification of <img src='/image/spc_char/alpha.gif'> amylase inhibitors from <i style="">Syzygium cumini </i>Linn seeds

677-680 The aqueous extract of S. cumini or Eugenia jambolana seeds and Psidium guajava leaves showed higher inhibition against the porcine pancreatic -amylase among the medicinal plants studied. The -amylase inhibitors from S.cumini seeds were separated from the extract by preparative thin layer chromatography into fractions with different Rf values. The fraction with Rf value between 0.285 and 0.43, which showed maximum inhibitory activity, was eluted and analyzed through LC-MS. The compounds identified from the seed extract of S. cumini were betulinic acid and 3,5,7,4`-tetrahydroxy flavanone, which were reported earlier from S. formosanum and other plants. Dixon plot showed that the inhibition was non-competitive in nature. </smarttagtype

Phyto-synthesis of silver nanoparticles using Alternanthera tenella leaf extract: an effective inhibitor for the migration of human breast adenocarcinoma (MCF-7) cells

In this study, phyto-synthesis of silver nanoparticles (AgNPs) was achieved using an aqueous leaf extract of Alternanthera tenella. The phytochemical screening results revealed that flavonoids are responsible for the AgNPs formation. The AgNPs were characterised using UV-visible spectrophotometer, field emission scanning microscopy/energy dispersive X-ray, transmission electron microscopy, fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction. The average size of the nanoparticles was found to be ≈48 nm. The EDX results show that strong signals were observed for the silver atoms. The strong band appearing at 1601-1595 cm-1 correspond to C-C stretching vibration from dienes in FT-IR spectrum indicating the formation of AgNPs. Human breast adenocarcinoma (MCF-7) cells treated with various concentrations of AgNPs showed a dose-dependent increase in cell inhibition. The IC50 value of the AgNPs was calculated to be 42.5 μg mL-1. The AgNPs showed a significant reduction in the migration of MCF-7 cells

Curcuminoid extraction from turmeric (curcuma longal.): efficacy of bromine-modified curcuminoids against food spoilage flora

Curcuminoids are nutraceutical compounds used worldwide for medicine as well as in food preparations. In the present study, curcuminoid extraction was optimized using response surface methodology. The antimicrobial properties of curcuminoids and bromine-modified curcuminoids (BMCs) were determined against food spoilage flora and foodborne pathogens. The maximum curcuminoid yield was obtained when turmeric, methanol and time were 5.77g, 22.52mL and 12.53h, respectively. The high-performance liquid chromatogram of the extracted curcuminoids indicated three peaks at 9.5, 10.1 and 10.7min, which correspond to bisdemethoxycurcumin, demethoxycurcumin and curcumin in the ratio of 28:24:48, respectively. Curcuminoids had a broad spectrum of antimicrobial activity. The minimum inhibitory concentration value of BMCs was significantly decreased to 34.5, 14.7 and 30.2% for the tested gram-positive bacteria, gram-negative bacteria and fungi, respectively. Practical Applications: This finding suggests that bromine-modified curcuminoids would be a good candidate for food manufacturing industries to control food spoilage flora and foodborne pathogens

Laccase mediated diclofenac transformation and cytotoxicity assessment on mouse fibroblast 3T3-L1 preadipocytes

Diclofenac is recently considered as one of the most devastating environmental pollutants, because of its biomagnification in the food chain which leads to potential harmful effects on non-targeted organisms. This study describes the optimized laccase mediated diclofenac transformation using response surface methodology (RSM) and cytotoxicity testing on mouse fibroblast 3T3-L1 preadipocytes. Three factors (laccase, syringaldehyde, reaction time) were used to optimize the diclofenac transformation. The optimum level of laccase, syringaldehyde and reaction time was found to be 1.91 U mL -1, 187 μg and 51 min for diclofenac transformation (20 mg L -1). The cytotoxicity assessment on mouse fibroblast 3T3-L1 preadipocytes showed that a maximum of 67.9% cell death occurred at 72 h treatment with diclofenac (200 μg mL-1), while the cells treated with laccase treated diclofenac (LTD) showed less toxicity on the cells. These findings can be addressed for the removal of diclofenac toxicit

Novel mechanisms in nutrient activation of the yeast Protein Kinase A pathway

In yeast the Protein Kinase A (PKA) pathway can be activated by a variety of nutrients. Fermentable sugars, like glucose and sucrose, trigger a spike in the cAMP level, followed by activation of PKA and phosphorylation of target proteins causing a.o. mobilization of reserve carbohydrates, repression of stress-related genes and induction of growth-related genes. Glucose and sucrose are sensed by a G-protein coupled receptor system that activates adenylate cyclase and also activates a bypass pathway causing direct activation of PKA. Addition of other essential nutrients, like nitrogen sources or phosphate, to glucose-repressed nitrogen-or phosphate-starved cells, also triggers rapid activation of the PKA pathway. In these cases cAMP is not involved as a second messenger. Amino acids are sensed by the Gap1 transceptor, previously considered only as an amino acid transporter. Recent results indicate that the amino acid ligand has to induce a specific conformational change for signaling. The same amino acid binding site is involved in transport and signaling. Similar results have been obtained for Pho84 which acts as a transceptor for phosphate activation of the PKA pathway. Ammonium activation of the PKA pathway in nitrogen-starved cells is mediated mainly by the Mep2 transceptor, which belongs to a different class of transporter proteins. Hence, different types of sensing systems are involved in control of the yeast PKA pathway by nutrients