Extraction and partial purification of secondary metabolites from endophytic actinomycetes of marine green algae Caulerpa racemosa against multi drug resistant uropathogens

The aim of this study is to identify potential antibacterial compounds of endophytic actinomycetes (EA) from marine algae Caulerpa racemosa for inhibit the multi drug resistant (MDR) Gram negative bacteria (GNB) including Eschericia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa), Proteus mirabilis (P. mirabilis), Klebsiella pnumonia (K. pnumoniae) and Enterobacter sp., which were confirmed by UTI panel antibiotic discs. Among the 100 EA, five strains were showed better antogonistic activity against all the selected uropathogens. In the ethyl acetate extract, the NMS 5 strains of EA showed excellent anti-bacterial activity against all the MDR uropathogen. Further, the NMS 5 extract was partially purified from thin layar chramatogaraphy (TLC) and spot 3 of TLC crude compound showed 14, 12mm zone of inhibition against both the uropathogens. In addition, the minimum inhibition concentration (MIC) of crude exhibited the inhibition percentage was 87 and 84 at 120 μg/ mL concentration. The MIC was confirmed by minimum bactericidal concentration (MBC) and it was indicated same as MIC. The treated NMS 5 crude compound of P. aeruginosa and K. pneumonia cells were showed more dead cells, intracellular damage and morphological damage with disaggregated cells by confocal laser scanning electron microscope (CLSM) and scanning electron microscope (SEM). Hence, the present study was revealed that the algae derived EA have the potential anti-bacterial metabolites for inhibition of MDR bacteria and it can be applied for various other infections after further purification

Biomarker response of climate change-induced ocean acidification and hypercapnia studies on brachyurian crab Portunus pelagicus

A laboratory level microcosm analysis of the impacts of ocean acidification on the environmental stress biomarkers in Portunus pelagicus (Linneaus 1758)exposed to a series of pH regimes expected in the year 2100 (pH 7.5 and 7.0) and leakage from a sub-seabed carbon dioxide storage site (pH 6.5 - 5.5) was carried out. Levels of the antioxidant enzyme catalase, the phase II detoxification enzyme, glutathione S. transferase, the lipid peroxidation biomarker, malondialdehyde, acetylcholinesterase, and reduced glutathione were estimated in the tissues of the exposed animals to validate theses enzymes as biomarkers of Hypercapnia. The integrated biomarkers indicated a stress full environment in all animals except those exposed to the control seawater (pH 8.1). The reducing pH was also observed to be highly lethal to the animals exposed to lower pH levels which were obvious from the rate of mortality in a short term of exposure. The present study substantiates the role of biomarkers as an early warning of ocean acidification at a sub-lethal level

Chitosan mediated gold nanoparticles against pathogenic bacteria, fungal strains and MCF-7 cancer cells

University Grants Commission, India: 39-559/2010 (SR

Anti-biofilm investigation of graphene/chitosan nanocomposites against biofilm producing P. aeruginosa and K. pneumoniae

In this study graphene/chitosan nanoparticles (GR/CS NCs) were developed. The homogenous combination of GR and CS was confirmed by FTIR spectroscopy. The combination of CS with GR sheets reduced the XRD intensity of the GR peak in GR/CS NCs, while TEM images revealed the immobile CS coating of GR sheets. Further, the anti-biofilm activity of GR/CS NCs was tested. The tests showed that the formation of biofilm by Pseudomonas aeruginosa and Klebsiella pneumoniae was inhibited at 40 square g/mL GR/CS NCs up to 94 and 92 %, respectively. The intracellular and cell surface damage of the bacteria was observed by CLSM and SEM. Also, GR/CS NCs produced a toxic effect of 90 % on Anemia franciscana at 70 square g/mL upon 24 h incubation. The recorded properties of the synthesized GR/CS NCs qualify them as potential agents against mull-drug resistant bacteria.National Natural Science Foundation of China: 41950410573, 91751206. Comisión Nacional de Investigación Científica y Tecnológica (CONICYT), CONICYT FONDECYT: 3180128. Deanship of Scientific Research at King Saud University: RG-1438-074

Anti -oxidant, anti -bacterial and anti-biofilm activity of biosynthesized silver nanoparticles using Gracilaria corticata against biofilm producing K. pneumoniae

Silver nanoparticles (Ag NPs) with anti -bacterial effects against the biofilm-producing bacteria Klebsiella pneu- moniae ( K. pneumoniae ) were synthesized using the marine seaweed Gracilaria corticata ( G. corticata ). Physiochemical characterization using UV -spectrometer, fourier transform infrared spectroscopy (FTIR) and X- ray diffraction (XRD) confirmed that the synthesized material consisted of Ag NPs. Morphological analysis using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) with energy -dispersive X-ray (EDX) analysis confirmed the shape, size, surface morphology, and available chemical composition of the Ag NPs. Furthermore, the rich phenolic and flavonoid content of G. corticata has excellent antioxidant activity, which was confirmed through gas chromatography -mass spectrometry (GC -MS) analysis. The highest anti- bacterial activity and biofilm reduction (88 %) of Ag NPs treated K. pneumoniae was observed at 50 ?g/mL and 100 ?g/mL concentrations respectively. The bacterial viability and exopolysaccharide production of K. pneu- moniae significantly decreased after treatment with Ag NPs. Morphological alterations and intracellular damageNational Natural Science Foundation of China 41950410573 31670009 China Postdoctoral Science Foundation 2019M663213 King Saud University RG-1438-091 Bharathidasan University 05441/URF/K7/2013 Confocal Laser Scanning Electron Microscope (DST-PURSE) SR/FT/LS-113/200

Time dependent inhibition of Morinda citrifolia essential oils against multi drug resistant bacteria and A549 lung cancer cells

Recent years, multi-drug resistant bacteria (MDRs) and lung cancer cells are threatening to human worldwide due to failure of sufficient drugs. It was suggested that the new sources needed to discover new varieties of drugs, antibiotics and other format to eradicate these infections. As like, the medicinal plant of Morinda citrifolia (M. citrifolia) was used in this study to inhibit both the bacterial infection and cancer cells. First, the LC-MS measurement was evidently reported the available essential oils from medicinal plant of M. citrifolia. It has excellent anti-bacterial properties against P. mirabilis, E. coli, P. aeruginosa and S. aureus with 24, 22, 26 and 18 zone of inhibition respectively by agar well diffusion. Subsequently, the liquid interference assay was exhibited 97 %, 96 %, 94 % and 90 % inhibition at 1000 µg/mL concentration for all the tested pathogens. In addition, M. citrifolia EOs have excellent anti-bacterial activity, and it arrested the bacterial growth completely at 1000 µg/mL concentration for 24 h after compared with other time intervals. Subsequently, the intracellular membranes and more death cells with condensed chromosome like structure were effectively observed by confocal laser scanning electron microscope. Then, invitro cytotoxicity result of M. citrifolia EOs treated A549 lung cancer cells was clearly observed. The cytotoxicity result confirmed that the 500 µg/mL of M. citrifolia EOs against A549 lung cancer cells as fixed as IC50 dose. Hence, current study conclude, M. citrifolia is the excellent medicinal plant to inactivate bacterial growth and cancer cells efficiently