South Asian Journal of Experimental Biology

Bacterial accumulation in edible bivalve, Villorita cyprinoides of Ashtamudi estuarine wetland, a Ramsar site in Kerala State, India

Letty Titus, Sulekha Balakrishnan Thamarakshi — Sat, 25 Jan 2025 00:00:00 +0000

The Ashtamudi Lake in Kerala, recognized under the Ramsar Convention, showcases rich biodiversity but faces pollution threats from human activities. Of particular concern is the potential bacterial contamination of inland fishery resources due to these anthropogenic influences. The present study, seasonally analysed the total heterotrophic bacteria (THB) and E. coli in water, sediment and Villorita cyprinoides respectively using pour plate and MPN methods. Water temperature, pH, salinity, DO and BOD of water samples were also estimated. The results showed the presence of THB in water was more in monsoon season and in sediments and the organism in premonsoon season. However, E. coli counts were more in all the media in monsoon season. The E. coli count slightly exceeded the standards set by European Union for Class A waters. In general, THB and MPN E. coli values were the highest in the oyster. Pearson’s correlation showed highly significant positive correlation between THB and E. coli in all the phases. pH and salinity showed highly significant positive correlation with BAF and highly significant negative correlation with DO and rainfall. Conversely, rainfall and BOD showed significant negative correlation with BAF. The present study indicates that the density of E. coli in shellfish at some locations exceeds the standard limit set by Indian Standards.

Studies on biological activities with effect of temperature on curry and neem leaves nanoparticles

Rajasekhar Eruva — Sat, 25 Jan 2025 00:00:00 +0000

Curry and neem leaves nanoparticles were designed to estimate the biological activities such as conductivity, pH-values, transmission percent, concentration and temperature. An experiment was carried out based on diffusion method. Results show that hydrogen ion concentration (pH) for the distilled water was neutral (7.0), the average pH-value of CU (7.44) and NE (7.42).The results indicated that the neem and curry leaves nanoparticles shown nearly same pH- value. It implies that antacid potentials present which will be caused by biological infective resistance to human beings. This kind of activity in general found to be rheumatic reluctance for many orthopedically pains. Significant differences were found with the effect of temperature, conductivity, concentration and pH-values of the curry and neem leaves nanoparticles. Concentration of the neem nanoparticles increases the conductivity also increases but the concentration of the curry leaves nanoparticles increases the conductivity will show interweave. It indicates that conductivity levels were responsible for the biological activity of the sample and positive significant (p<0.05) relationship between the conductivity of the curry and neem leaves nanoparticles.

Enhancing green chili growth using eggshell waste as a carrier for NPK biofertilizer consortium in soil

Palash Ghorai, Dipankar Ghosh — Sat, 25 Jan 2025 00:00:00 +0000

Biofertilizer technology continues to be derailed by the short shelf life of inoculants. The survival efficiency of rhizobacterial inoculants in biofertilizer formulations dramatically depends on the choice of carrier material. The use of wastes as carriers for biofertilizer formulations is a commonly explored option because of their ready availability, cost-effectiveness and ability to affect soil health. The present study investigated the suitability of eggshell (ES) as a carrier for cow dung waste (CDC) and lignite (L) in the combined formulation of green chili plant growth using three rhizobacterial inoculants, namely, the N-fixing bacterium Enterobacter sp. GG1, the P-solubilizing bacterium Bacillus sonorensis GG2, and the K-solubilizing bacterium Lysinibacillus fusiformis GG3, under room-temperature conditions. The combination of eggshell and lignite supported the maximum viability of Enterobacter sp. GG1 (9.09±0.025 log CFU g-1), B. sonorensis GG2 (9.19±0.023025 log CFU g-1), and L. fusiformis GG3 (9.09±0.042025 log CFU g-1) under six-month room conditions. A new physiochemically formulated eggshell with an NPK consortium exhibited a significant correlation at the 0.05 significance level (2-tailed). Considering the results of this study on the optimization of green chili plants after two months of treatment under environmental conditions, the maximum growth of plants inoculated with the NPK consortium (ES+L) was 159.16% shoot and 40.58% root growth, with increased available plant nutrients in clayey soil (i.e., N 64.54±1.81 ppm, P 29.51±1.65 ppm, and K 73.95±6.43 ppm). The findings of this study highlight the potential of eggshell waste as a sustainable and effective carrier material for biofertilizer formulations, addressing waste management challenges to enhance rhizobacterial viability and improve nutrient availability in soil.

Toxicological Impacts of Pendimethalin on the Brain of Cyprinus carpio: A Histopathological Approach

Inder Singh Rana, Sushma Sharma, Rajinder Kumar, Jyoti Verma — Sat, 25 Jan 2025 00:00:00 +0000

Agricultural pesticides negatively impact aquatic ecosystems. A dinitroaniline herbicide pendimethalin is used to control weeds and unwanted grasses in crop fields but it can reach water streams indirectly and harm aquatic fauna including fish. The main objective of our study was to find histopathological alterations caused by pendimethalin in the brain of Cyprinus carpio. The whole procedure was done using a histopathological approach by processing brain tissue, making slides, and analyzing these slides under a light microscope to observe changes in brain tissue. Acute toxicity was found by obtaining 96h LC50 value i.e., 2.20μl/L. Fishes were divided into 3 groups: The first group was assigned as the control group., second and third groups was administered with 1/10th and 1/15th concentration of calculated 96 h LC50 (I.e., 0.22μl/L and .146μl/L). The key findings of our study demonstrated that control fish brains do not show any morphological changes in structure. The second and third groups exposed to pendimethalin showed severe damage to the brain including vacuolization, necrosis in neurons, deformed pyramidal cells, clustering of nuclei, binucleate formation and nuclear infiltration compared to the control fish brain. The findings of our study have significant implications for understanding the neurotoxic effects of pendimethalin on aquatic species, specifically about brain structure and function. The study emphasizes the crucial role of neurotoxicity assessments in environmental risk assessments, which can save particular species and preserve the general equilibrium and resilience of aquatic habitats.

Comparative Study of the Synthesis of Silver, Copper, and Iron oxide Nanoparticles via Chemical and Green Methods Using Corn Bract for Enhanced Antibacterial Activity

B. Sadhbhavana, Y.V. Tanishq, Isha Deep, K. Deepak Raj, Chaitanya Kumari Samala — Sat, 25 Jan 2025 00:00:00 +0000

The increasing demand for sustainable and eco-friendly solutions in nanotechnology highlights the importance of exploring novel methods for the synthesis of nanoparticles. Metal nanoparticles have unique properties and are particularly significant in addressing antimicrobial resistance and environmental challenges. This study aimed to synthesize silver, copper, and iron nanoparticles from waste corn bract using chemical and green synthesis methods and evaluate their antibacterial properties. Corn bract extract was prepared and used as a reducing and stabilizing agent in green synthesis, while the comparison was done by conventional chemical methods. The nanoparticles were characterized using UV-visible spectroscopy, FTIR, and SEM, and their antibacterial activity was tested against Gram-positive (Bacillus sp., Staphylococcus sp.) and Gram-negative (Escherichia coli, Klebsiella sp., Pseudomonas sp.) bacteria through the well diffusion method. The green-synthesized silver nanoparticles exhibited the highest antibacterial efficacy, especially against Pseudomonas sp. and E. coli, followed by copper and iron nanoparticles. Phytochemicals in corn bract extract enhanced the stability and bioactivity of green-synthesized nanoparticles, as confirmed by FTIR analysis. The results of this investigation underscore the capabilities of agricultural waste in facilitating sustainable nanoparticle production, wherein green synthesis provides enhanced antibacterial attributes in comparison to traditional chemical approaches. This research emphasizes the significance of nanoparticles synthesized through green methods in addressing antimicrobial resistance and highlights their role as a scalable and environmentally sustainable option for generating effective antimicrobial agents.