Effects of Moringa oleifera leaves extract, vitamin C, and taurine co-exposures on calcium and metallothionein levels, oxidative stress, and gill histopathological changes in Clarias gariepinus exposed to sub-lethal cadmium.

Cadmium aquatic environmental pollution poses great threats to fish and their would-be consumers. The present work investigated the effects of ethyl acetate extract of Moringa oleifera leaves (EAEMOL), vitamin C, and taurine co-exposures on calcium and metallothionein levels, oxidative stress, and gill histopathological changes in Clarias gariepinus exposed to sub-lethal cadmium (CdCl2) for 28 days. Fish were exposed to CdCl2 only (1.048 mg/L) as well as co-exposed with EAEMOL (20 mg/L), vitamin C (5 mg/L), and taurine (5 mg/L) separately. There was significant (p < 0.05) deterioration in fish water quality with increasing exposure period but no significant (p > 0.05) changes occurred between the exposed groups. However, the co-exposure of EAEMOL, vitamin C, and taurine did not significantly (p > 0.05) improve the CdCl2-induced fish water quality deterioration. Sub-lethal exposure to CdCl2 only caused significant (p < 0.05) increase in the serum malondialdehyde (MDA) and liver metallothionein (MT) levels with significant (p < 0.05) decrease in serum catalase activity only. However, EAEMOL, vitamin C, and taurine co-exposures did not significantly (p > 0.05) improve the MDA, superoxide dismutase, catalase, and glutathione activities, as well as MT and calcium (Ca2+) levels, condition factor (CF), hepatosomatic index (HSI), and gill histopathological changes induced by the CdCl2 exposure. Similarly, none of the present exposures, CdCl2 only or its co-exposures with EAEMOL, vitamin C, and taurine significantly (p > 0.05) altered the normal functioning of the gills despite the observed histopathological changes based on the degree of tissue change protocol. Therefore, EAEMOL, vitamin C, and taurine co-exposures, as administered in the present case, did not considerably alter the physicochemical parameters of the experimental fish water. However, outside significantly (p < 0.05) increasing MDA level, EAEMOL, vitamin C, and taurine co-exposures did not significantly (p > 0.05) improve the CdCl2-induced Ca2+, MT, CF, HSI, and gill histopathological alterations by sub-lethal CdCl2 exposure of C. gariepinus.

Methanolic soluble fractions of lingzhi or reishi medicinal mushroom, Ganoderma lucidum (higher Basidiomycetes) extract inhibit neuraminidase activity in Newcastle disease virus (LaSota).

The antineuraminidase activity of different organic soluble fractions of Ganoderma lucidum extract was investigated using inhibition of hemagglutination and elution of chicken erythrocytes by Newcastle disease virus (NDV). Fractions of methanol, ethylacetate, and normal butanol (n-butanol) of the G. lucidum were tested against neuraminidase producing NDV as antigen. Different dilutions of the organic soluble fractions inhibited elution of 1% red blood cells by neuraminidase of NDV While the methanolic and n-butanol extracts inhibited neuraminidase activity even at a dilution of 1:16 and that of ethylacetate fraction inhibited even at 1:32 respectively. This finding indicates that G. lucidum has some antineuraminidase activity against NDV and may be exploited in the management of NDV infection.