Identification of Chlorophene in a Backwater Stream in Kerala (India) and its Sonochemical Degradation StudiesChlorophene, a chlorinated phenolic compound and a well-known emerging pollutant due to its extensive use as an antimicrobial agent, has been identified in a local backwater stream using liquid chromatography quadrupole time of flight MS (LC-Q-TOF-MS). The concentration of chlorophene has been calculated as 6 Â 10 À7 mol L
À1(0.132 ppm). In order to develop a suitable treatment protocol, ultrasound mediated oxidative degradation has been carried out. Prior to the investigation of chlorophene in the backwater sample, the degradation in pure water has been investigated at 620 kHz and 40.25 W mL
À1. Complete disappearance of chlorophene was observed within 40 min of sonication. The presence of various inorganic ions had no significant influence on the degradation. A complete chemical oxygen demand removal in the local backwater samples was achieved within 3 h of sonication. Three major intermediate products have been identified by LC-Q-TOF-MS and a plausible mechanism of the degradation is proposed. The same method was applied for the backwater sample containing chlorophene with a concentration of 6 Â 10 À7 mol L
À1. Complete disappearance of chlorophene and nearly 85.7% COD removal was observed in this system as well.
BACKGROUND
Lipopeptides from the Bacillus spp. possess an excellent spectrum of antimicrobial properties which make them suitable candidates to be explored for the food, agricultural, pharmaceutical and biotechnological applications. As the low yield of the lipopeptides limits their applications, methods to enhance their production are highly significant.
RESULTS
In this study, extracts prepared from endophytic Bacillus sp. Fcl1 cultured in the presence of various supplements were screened for antifungal activity against Pythium aphanidermatum. From the results, the supplementation of carbon sources and zinc oxide nanoparticles (ZnONPs) was found to have an enhancement effect on the antifungal activity of Bacillus sp. Fcl1. Among these, the highest antifungal activity (73.2%) could be observed for the Fcl1 sample cultured with 5 mg L−1 of ZnONP supplementation. The growth of Fcl1 in the presence of ZnONPs also indicated its compatibility with the nano‐supplement in the concentration range used. By liquid chromatography quadrupole time‐of‐flight mass spectrometry (LC‐Q‐TOF‐MS) analysis, the synthesis of increased numbers of lipopeptide surfactin derivatives could be identified from the extracts of Fcl1 prepared from the carbon sources and ZnONP‐supplemented cultures. In addition to the surfactin derivatives, the presence of another lipopeptide iturin was also detected from the extracts of Fcl1 cultured with ZnONPs.
CONCLUSION
ZnONP supplementation was found to enhance antifungal activity and lipopeptide production in the Bacillus sp. Fcl1. The use of nanoparticles to enhance the antifungal mechanisms of Fcl1 as observed in the study provides novel insights to explore its applications for sustainable agricultural productivity.
The presence of emerging contaminants (ECs) in different aquatic systems may contribute to hazardous effects on aquatic organisms and subsequently on human health. In the present work, liquid chromatography coupled to a quadrupole time of flight mass spectrometer (LC-Q-ToF-MS) was used to identify and quantify a series of ECs in Periyar River in Aluva region, Kerala, India. The water samples were pre concentrated using solid-phase extraction (SPE) prior to analysis. The compounds were probed in both positive and negative ionization mode using electro spray ionization (ESI). Method validations were performed for linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy, and precision (intraday and inter day). The ECs were quantified using standard calibration curve. The identified nine ECs include pharmaceuticals, personal care products, steroids, surfactants, and phthalate. A relatively high concentration was observed in the case of 2-dodecyl benzene sulfonic acid (1012 ng/l) and low concentration was observed for lignocaine (4.3 ng/l; since this is below LOQ, the value is only approximate). In addition, we have identified another 28 organic compounds using the technique of non-target analysis out of which seven compounds fall in the category of surfactants. Being the first report on ECs in Periyar River, the data is very important as this river is one of the biggest and important rivers of Kerala having several purification units for drinking water in the province.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.