Manipal University

About: Manipal University is a education organization based out in Manipal, Karnataka, India. It is known for research contribution in the topics: Population & Medicine. The organization has 9525 authors who have published 11207 publications receiving 110687 citations.

Photocatalytic degradation of Rhodamine B by zinc oxide nanoparticles synthesized using the leaf extract of Cyanometra ramiflora

Abstract: In the current study, the green synthesis of zinc oxide nanoparticles (ZnONPs) using the leaf extract of Cyanometra ramiflora and zinc acetate precursor is presented. The phyto-components of the extract aided the reduction and the formation of nanoparticles. The purified ZnONPs were characterized by UV–Vis spectroscopy, SEM, EDS, XRD, BET, and FTIR techniques. A sharp absorption maximum at 360 nm in the UV–Vis data affirmed the formation of ZnONPs. SEM image revealed the nanoflower morphology and EDS showed strong signals for zinc and oxygen elements. XRD spectrum confirmed the hexagonal wurtzite crystalline structure of size 13.33 nm. A significant large surface area of 16.27 m2/g with mesopores, was affirmed using BET analysis. FTIR substantiated the existence of the characteristic zinc and oxygen bonding vibrations at 557 cm−1, 511 cm−1 and 433 cm−1. The photocatalytic activity of the ZnONPs was examined using the pollutant dye, Rhodamine B. A remarkable degradation efficiency of 98% within 200 min was achieved under sunlight irradiation and a degradation constant of 0.017 min−1 was obtained. Therefore, ZnONPs synthesized using a cheap and abundant source – the leaf extract of C.ramiflora possibly will play a promising part in the degradation of toxic dyes present in the wastewater.

Core–EP inverse

Abstract: In this work, we introduce a notion of ‘core–EP inverse’ for a square matrix which is not essentially of index one. This extends the notion of ‘core inverse’, which was initially defined for the matrices of index one. The properties of matrices having ‘core–EP inverse’ and ‘core–EP generalized inverse’ are studied, and obtained a formula to compute the core–EP generalized inverse from a particular linear combination of minors of given matrix.

Antimicrobial and Enzyme Activity of Mangrove Endophytic Fungi of Southwest Coast of India

Abstract: The antimicrobial potential of 14 endophytic fungi isolated from Acanthus ilicifolius and Acrostichum aureum towards selected bacteria (Bacillus subtilis, Enterococcus sp., Klebsiella pneumoniae, Pseudomonas aerugionsa, Salmonella typhi and Staphylococcus aureus) and fungi (Candida albicans and Trichophyton metagrophytes) was tested using ethyl acetate extract of fungi cultivated under solid-state fermentation (SSF). Aspergillus spp. showed promising antagonistic features. All test bacteria were inhibited by sterile isolate MSI 1. Cumulospora marina and Pestalotiopsis sp. showed considerable inhibition on Gram-positive and Gram-negative bacteria. Crude ethyl extracts derived from submerged fermentation (SmF) of four endophytes showing positive results were further evaluated. Aspergillus sp. 3 and Pestalotiopsis sp. inhibited many bacteria and Candida albicans, while inhibition by Aspergillus sp. 2 and MSI 1 was confined to bacteria. Crude ethyl acetate extracts purified by TLC of four endophytes grown under SmF showed many fluorescent fractions. Two fractions of Aspergillus sp. 3 showed high antimicrobial activity. One of the fractions of Pestalotiopsis sp. showed considerable inhibition of Bacillus subtilis, Staphylococcus aureus and Candida albicans. Seven endophytic fungi were assessed for the production of extracellular enzymes (amylase, cellulase, chitinase, laccase, lipase, protease and tyrosinase) by culture plate method. Cellulase and lipase activity was present in all fungi, while amylase and protease in a few. No fungi exhibited chitinase, laccase and tyrosinase activity. Enzyme production of Pestalotiopsis sp. (cellulase by SmF; xylanase, pectinase and protease by SSF) at pH 7 and pH 9 during 3-15 days of fermentation was assessed. The Cellulase activity was highest at pH 7 on 6 day, while xylanase activity was highest on 9 day at pH 9. Highest activity of pectinase was seen on 6 (pH 7) and 9 days (pH 9). Protease activity was highest on 6 day at pH 7 and 9.