Annamalai University

About: Annamalai University is a education organization based out in Chidambaram, Tamil Nadu, India. It is known for research contribution in the topics: Lipid peroxidation & Antioxidant. The organization has 8098 authors who have published 10758 publications receiving 203872 citations.

Environmental hydrogeochemistry and genesis of fluoride in groundwaters of Dindigul district, Tamilnadu (India)

Abstract: Fluoride (F−) is an indispensable element for the human’s skeletal and dental health at prescribed levels and becomes lethal at higher levels. Spatial–temporal variability of F− and its geochemical control/association with other dissolved ions in groundwater in the Dindigul district of Tamilnadu (India) were conducted to describe the geochemical dynamics of F– in response to seasonal variability. High concentrations of fluoride (≥1.5 mg L−1) were observed in the northern region of the district. High levels of F− were observed in non-monsoon periods and low levels in monsoon, because of dilution by precipitation. Bicarbonate was well correlated with F− which explains that both ions were derived from the weathering. While F− has a very weak correlation with silica, this implies that the silicate weathering does not supply F− to the groundwater system. The F− pollution in Dindigul groundwaters is mainly driven by two factors: (1) the geogenic weathering inputs, the geology of this area mainly comprises fluoride bearing minerals (e.g. hornblende biotite gneiss and charnockite); (2) the anthropogenic inputs (agri-fertilizers and tannery waste). Further, F− in the study area is mainly attributed to geogenic sources during pre and postmonsoons and anthropogenic sources in monsoon periods.

Antihyperglycemic activity of Eclipta alba leaf on alloxan-induced diabetic rats.

Abstract: Eclipta alba, an indigenous medicinal plant, has a folk (Siddha and Ayurvedha) reputation in rural southern India as a hypoglycemic agent. In order to confirm this claim, the present study was carried out to evaluate the antihyperglycemic effect of E. alba and to study the activities of liver hexokinase and gluconeogenic enzymes such as glucose-6-phosphatase and fructose 1,6-bisphosphatase in the liver of control and alloxan-diabetic rats. Oral administration of leaf suspension of E. alba (2 and 4 g/kg body weight) for 60 days resulted in significant reduction in blood glucose (from 372.0 +/- 33.2 to 117.0 +/- 22.8), glycosylated hemoglobin HbA(1)c, a decrease in the activities of glucose-6 phosphatase and fructose 1,6-bisphosphatase, and an increase in the activity of liver hexokinase. E. alba at dose of 2 g/kg body weight exhibited better sugar reduction than 4 g/kg body weight. Thus, the present study clearly shows that the oral administration of E. alba possess potent antihyperglycemic activity.

Nonquenching of Charge Carriers by Fe3O4 Core in Fe3O4/ZnO Nanosheet Photocatalyst

Abstract: Fe3O4-implanted ZnO and pristine ZnO nanosheets have been synthesized hydrothermally High-resolution scanning electron microscopy, high-resolution transmission electron microscopy, energy dispersive X-ray spectroscopy, elemental mapping, selected area electron diffractometry, powder X-ray diffractometry, Raman spectroscopy, vibrating sample magnetometry, solid state impedance spectroscopy, UV–visible diffuse reflectance spectroscopy, and photoluminescence spectroscopy show implantation of Fe3O4 in ZnO nanosheets Fe3O4 core with ZnO shell is of type I core/shell heterostructure which is to quench charge carriers and suppress photocatalysis But the photocatalytic activity is not suppressed on implantation of Fe3O4 in ZnO nanosheets, and time controlled single photon counting lifetime spectroscopy shows that the photogenerated charge carriers are not quenched by the Fe3O4 core in the ZnO nanosheets The composite nanosheets are photostable, reusable, and magnetically recoverable, revealing potential appli

Studies on the impact of biosynthesized silver nanoparticles (AgNPs) in relation to malaria and filariasis vector control against Anopheles stephensi Liston and Culex quinquefasciatus Say (Diptera: Culicidae)

Abstract: Biosynthesized nanoparticles have been achieved using environmentally acceptable plant extract and eco-friendly reducing and capping agents. The present study was based on assessments of the larvicidal activities to determine the efficacies of synthesized silver nanoparticles (AgNPs) using aqueous leaf extract of Vinca rosea (L.) (Apocynaceae) against the larvae of malaria vector Anopheles stephensi Liston and filariasis vector Culex quinquefasciatus Say (Diptera: Culicidae). Larvae were exposed to varying concentrations of aqueous extract of V. rosea and synthesized AgNPs for 24, 48, and 72 h. AgNPs were rapidly synthesized using the leaf extract of V. rosea, and the formation of nanoparticles was observed within 15 min. The results recorded from UV–Vis spectrum, Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) support the biosynthesis and characterization of AgNPs. The formation of the AgNPs synthesized from the XRD spectrum compared with the Bragg reflections at 2θ = 29.36, 38.26, 44.51, 63.54, and 77.13° which can be indexed to the (121), (111), (200), (220), and (311) orientations, respectively, confirmed the presence of AgNPs. The FTIR spectra of AgNPs exhibited prominent peaks at the spectra showed sharp and strong absorption band at 3,406.71 to 3,431.90 cm−1 double in case of NH2 group of a primary amine (N–H stretch). The presence of the sharp peak at 2,926.54 to 2,925.80 cm−1 very broad often looks like distorted baseline (O–H carboxylic acids). The band 1,633.26 to 1,625.81 cm−1 was assigned to C = C alkenes, aromatic ring stretching vibration, respectively. SEM analysis of the synthesized AgNPs clearly showed the clustered and irregular shapes, mostly aggregated and having the size of 120 nm. TEM reveals spherical shape of synthesized AgNPs. Particle size analysis revealed that the size of particles ranges from 25 to 47 nm with average size of 34.61 nm. Energy-dispersive X-ray spectroscopy showed the complete chemical composition of the synthesized AgNPs. In larvicidal activity, the results showed that the maximum efficacy was observed in synthesized AgNPs against the fourth instar larvae of A. stephensi (LC50 = 12.47 and 16.84 mg/mL and LC90 = 36.33 and 68.62 mg/mL) on 48 and 72 h of exposure and against C. quinquefasciatus (LC50 = 43.80 mg/mL and LC90 = 120.54 mg/mL) on 72-h exposure, and aqueous extract showed 100 % mortality against A. stephensi and C. quinquefasciatus (LC50 = 78.62 and 55.21 mg/mL and LC90 = 184.85 and 112.72 mg/mL) on 72-h exposure at concentrations of 50 mg/mL, respectively. The AgNPs did not exhibit any noticeable toxicity on Poecilia reticulata after 24, 48, and 72 h of exposure. These results suggest that the synthesized AgNPs have the potential to be used as an ideal eco-friendly approach for the control of the A. stephensi and C. quinquefasciatus. This method is considered as a new approach to control vectors. Therefore, this study provides the first report on the mosquito larvicidal activity of V. rosea synthesized AgNPs against vectors.

Probiotics - the versatile functional food ingredients.

Abstract: Probiotics are live microbes which when administered in adequate amounts as functional food ingredients confer a health benefit on the host. Their versatility is in terms of their usage which ranges from the humans to the ruminants, pigs and poultry, and also in aquaculture practices. In this review, the microorganisms frequently used as probiotics in human and animal welfare has been described, and also highlighted are the necessary criteria required to be fulfilled for their use in humans on the one hand and on the other as microbial feed additives in animal husbandry. Further elaborated in this article are the sources from where probiotics can be derived, the possible mechanisms by which they act, and their future potential role as antioxidants is also discussed.