Review: Endocrine disrupting chemicals (phenol and phthalates) in the South African environment: a need for more monitoring

There has been increasing concern about the impacts of exposure to chemical compounds with endocrine disrupting activities in the environment, especially aquatic environments, to wildlife and humans. South Africa is known to have used and abused most chemicals listed by developed and developing countries as endocrine-disrupting chemicals. Endocrinedisrupting chemicals have been reported in water, sediment and serum, as well as in fish tissue samples, at a level that could trigger endocrine disruption in humans and wildlife. Although some monitoring has been reported, particularly in watersystems within the country, information on EDCs in other environmental matrices is scanty. The water systems monitored so far are very few. The strongest economy in Africa, and an emerging world economy depending on agriculture, mining, manufacturing and industry, needs to focus more on monitoring and to strengthen government organs and institutions to monitor and ensure environmental safety.Keywords: Endocrine disrupting chemicals (EDCs), phenols, phthalates, monitoring, South Afric

Biological synthesis of silver nanoparticles using Citrus sinesis seeds: Effects on hepatic and renal functional integrities and antioxidant activities.

Objective: This work reports the possible toxicological effects of AgNPs on the liver and kidney. Additionally, it also beamed its searchlight on its effects on the antioxidant defense mechanism in male Wistar rats.Method: Male Wistar rats (n=28) were used for the study. Control animals (n=7) were exposed to only drinking ware ad-libitum for 12 weeks. The remaining 21 rats were randomized into 3 groups of 7 animals each and were exposed to 50, 150 and 250 kg/mg body weight AgNPs biosynthesized from Citrus sinensisi for the same period after which blood and liver were removed from the rats and analyzed spectrophotometrically.Results: A non-significant reduction of plasma ALT, AST, ?GT and ALP characterized the effects of AgNPs in the animal tested. Similarly, AgNPs significantly depleted the plasma creatinine and urea level. The exposure also up-regulated the activities/concentration of antioxidant markers. Malondialdehyde concentration was also significantly depleted by AgNPs.Conclusion: The findings from this study revealed that biologically synthesized AgNPs induced no toxicological potential on hepatic and renal structural and functional integrity. Meanwhile, it enhanced the activities and concentration of antioxidant markers

Inhibition of lipid peroxidation and free radical scavenging activities of methanolic leaf extract of Psidium guajava

Objectives: Studies have linked the generation of free radicals with the incidence of degenerative diseases. Antioxidants from plant origin have been proved to play a major role in mitigating against free radicals-induced oxidative damage. This study aimed at assessing the in-vitro and in-vivo antioxidant capability of Psidium guajava leafMethods: The leaves were collected and extracted with 70% methanol. Total phenolic, and flavonoids contents, 2,2-diphenyl-1-picrylhydrazyl and Hydroxyl radicals scavenging activities, and inhibition of lipid peroxidation potential of the extract were assessed. Furthermore, rats (n=21) randomized into three groups were exposed to 50, 150, and 250 mg/kg body weight of the extract for 30 days. Control animals (n=7) received corn oil, after which blood and liver were excised for antioxidant assay.Results: The extract is rich in phenolic and flavonoid compounds. It scavenged DPPH and hydroxyl radicals and inhibits lipid peroxidation in-vitro. In-vivo, it increased the activities of hepatic superoxide dismutase, catalase, glutathione peroxidase, and plasma paraoxonase, and the concentration of hepatic reduced glutathione and MDA.Conclusion: Psidium guajava leaf extract is a potential source of natural antioxidant compounds, capable of supplementing the body's antioxidant defense system