The effects of different concentrations of cadmium chloride on the extent of lipid peroxidation (LPO) and alterations in the antioxidant enzyme activities were studied in liver, kidney and gill tissues of freshwater murrel, Channa punctatus. The fish specimens were exposed to 6.7, 13.4 and 20.1 mg l(-1) sublethal concentrations of cadmium chloride and the oxidative stress was assessed after 24, 48, 72 and 96 h post-exposure. The biomarkers selected for the study were thiobarbituric acid reactive substances for assessing the extent of lipid peroxidation and antioxidant defense system such as reduced glutathione (GSH), glutathione reductase (GR), glutathione peroxidase (GP(X)), glutathione-S-transferase (GST), catalase (CAT) and superoxide dismutase (SOD) activities. In general, the cadmium exposure elevated the LPO in subject tissues of treated group and modulated the activities of GPx, GST, SOD, CAT, GR and level of GSH after given exposure as compared to the control. All enzymes activities, except CAT (in kidney and gills), and amount of LPO elevated significantly (P < 0.05) in treated group with respect to control in all tissues, while significant difference was not observed between the exposed concentrations and within exposure duration. The results indicated that increase in LPO level and the fluctuation in antioxidant defense system in fish could be due to cadmium-induced increase in the production of reactive oxygen species (ROS). The potential role of these parameters as biomarkers of heavy metal pollution in aquatic system is discussed.

The East River tidal strait, located between New York Harbor and Western Long Island Sound, is characterized by high suspended silt concentrations with low organic content kept in suspension by intense tidal currents. Inorganic nutrients, including nitrate, nitrite, ammonia, and phosphate, were high even during the summer. Dissolved inorganic nitrogen (DIN) concentrations generally were above 20 lM and did not likely limit phytoplankton growth. Despite high nutrient concentrations, median chlorophyll a concentration was only 1.53 lg l -1 , making the East River tidal strait a high-nutrient, low-chlorophyll (HNLC) area, likely a result of suspended silt blocking light penetration into the surface water. There were times at which the ratio of mixed layer to depth of the euphotic zone was generally greater than what has been suggested for phytoplankton to produce net primary production. The high-nutrient East River tidal strait is likely one of the sources of nutrients fueling summer phytoplankton production and consequent hypoxia in the Western Long Island Sound as silt settles from surface water in the lower turbulence conditions of the western narrows of Long Island Sound, thereby allowing light penetration and subsequent consumption of dissolved nutrients by phytoplankton.

Fish, being an important native of the aquatic ecosystem, are exposed to multipollution states and are therefore considered as model organisms for ecotoxicological studies of aquatic pollutants, including metal toxicity. We investigated oxidative stress (OS) in liver, kidney and gill tissues through antioxidant enzyme activities and genotoxicity induced in whole blood and gill tissues through comet assay and micronucleus (MN) test in Cyprinus carpio after 96-hour in vivo static exposure to potassium dichromate at three sublethal (SL) test concentrations, including SL-I [93.95 mg/L, i.e. one quarter of half-maximal lethal concentration (LC50)], SL-II (187.9 mg/L, i.e. one half of LC50), and SL-III (281.85 mg/L, i.e. three quarters of LC50), along with a control. The 96-hour LC50 value for potassium dichromate was estimated to be 375.8 mg/L in a static system in the test species. Tissues samples were collected at 24, 48, 72 and 96 hours postexposure. Results indicated that the exposed fish experienced OS as characterized by significant (p < 0.05) variation in antioxidant enzyme activities, as compared to the control. Activities of superoxide dismutase and glutathione peroxidase increased, whereas activity of catalase decreased with the progression of the experiment. The mean percent DNA damage in comet tail and MN induction in gills and whole blood showed a concentration-dependent increase up to 96-hour exposure. The findings of this study would be helpful in organ-specific risk assessment of Cr(VI)-induced OS and genotoxicity in fishes.

Background. Albizialebbeck is a deciduous tree having tremendous medicinal utilities, for example, respiratory, skin, gastrointestinal, oral disorders, eye, urinary, genital, anorectal, inflammatory, and neurological disorders, and venereal diseases. Several studies have been undertaken on the medicinal and traditional values of A. lebbeck. Objective. The detailed information about its medicinal uses and pharmacological implications is highly scattered and distributed in different data sources. Hence, the study was conducted to supply an inclusive review of its ethnomedicinal uses, phytochemicals, and the available pharmacological attributes supporting its efficiency in traditional medicine. Method. Literature surveys were conducted on this medicinal plant via search engines like Google Scholar, PubMed, and Science Direct, and obtained information up to December 2020 has been assessed and analyzed for this study. Results. Systematic investigation revealed that A. lebbeck consists of various phytochemicals, including major alkaloids, flavonoids, saponins, and terpenoids. Its crude extract, fraction, and bioactive compounds exhibited potent adulticidal, antiallergic, anticancer, anticonvulsant, antidiabetic, antidiarrheal, anti-inflammatory, antimicrobial, antinociceptive, antioxidant, antiparasitic, antipyretic, antivenom, estrogenic, neuroprotective, nootropic, ovicidal, and wound healing activities. Conclusions. This study proposes that A. lebbeck remains a rich source of phytochemicals with various biological activities which possess outstanding therapeutic benefits to humanity across the world. However, studies are required to estimate the potential side effects. Moreover, mechanistic physiognomies of the isolated compounds with known bioactivities are quite limited; thus, forthcoming research needs to focus on the mechanisms of these active phytochemicals to facilitate their potential enrolling for drug discovery.