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This study was carried out to determine physiological and biochemical changes in C. moschata inoculated with a Nigerian strain of MWMV isolated from Lagenaria breviflora in Calabar, Nigeria. The virus infection resulted in significant (p#0.05) reductions in plant height, leaf area and number of leaves produces with highest percentage difference of 39.3% (42 PID), 60.9% (35 PID) and 25.7% (49 PID), respectively. There was a significant (p#0.05) difference in chlorophyll content between inoculated and healthy plants. The chlorophyll content of inoculated plants at all stages of growth was lower compared with the healthy plants. Chlorophyll b content was higher than Chl a in both inoculated and healthy plants. Chlorophyll a, b and total Chlorophyll were significantly reduced in inoculated plants when compared with the healthy ones. Of the twelve photochemicals screened, alkaloids, glycosides, saponins, tannins, terpenoids, steroids, polyphenols and reducing sugars were present while phlobatanins, anthraquinones and hydroxymethyl anthraquinones were absent. Moroccan watermelon mosaic virus engendered reductions in alkaloids (32.1%), reducing sugars (42.0%), saponins (33.6%), terpenoids (25.0%) and steroids (15.0%) and increase in inoculated samples of glycosides (14.8%) and flavonoids (12.5%). Effect of MWMV on proximate compositions of C. moschata revealed significant p#0.05) reductions in lipid (25.0%) and ash (14.6%) and significant (p$0.05) increases in protein (23.4%) and fibre (10.5%). Effect of the virus on carotene, vitamin A and C were insignificant. Infection of MWMV also led to significant decreases in the contents of K (48%), Fe (28.6%), Zn (25.0%) and Mg (22.0%), while Cu recorded 100% increase in inoculated samples. Marginal increase in Ca and P were recorded in inoculated samples. Infection of MWMV on antioxidants caused significant increase in inoculated samples of hydrocyanic acid and insignificant increases in total and soluble oxalate and phytic acid. Increases recorded in the antioxidant contents in plants inoculated with MWMV resulted in reduced bioavailability of minerals in the vegetable. Reduction in chlorophyll contents in inoculated plants would be a major factor explaining poor growth of host plants with attendant reductions in mineral elements of C. moschata. Changes in physiological and biochemical parameters induced by MWMV altered vital metabolic processes of C. moschata.

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Background: Mangroves are among the most productive intertidal ecosystems on earth. They serve as nursery and breeding grounds for several commercially important species of marine fauna. Despite their economic and ecological importance, they are under threat from over-exploitation and organic and inorganic pollution sources. This has led to their use as bio-indicators for pollution monitoring programmes. Therefore, the need to periodically monitor the Cross River Estuary mangroves for heavy metals pollution should not be overemphasized given the high premium placed on this ecosystem. Objectives: The present study was aimed at evaluating mangrove sediments and tissues for heavy metals accumulation in the different tidal levels of Cross River Estuary which will be an indicator for pollution. Method: Ten random samples of composite surface sediments (0-5 cm) were collected from low, mid and high tidal levels using a modified Van Veen (0.1 m 2 ) grab sampler. Also samples of senescent leaves, barks and roots of randomly selected ten individual plants of Nypa fruticans (low tide), Rhizophora racemosa (mid tide) and Avicennia africana (high tide) were also collected for heavy metal analyses during the year 2011. Result: The results showed that there were significant variations (p<0.05) in heavy metals deposition across the tidal levels. In the mangrove sediments, iron (Fe) content (415.8 mg gG 1 dry weight) was highest in the high tidal level where A. africana was predominantly sampled while N. fruticans (low tide) had the lowest deposition of the metal (304.4 mg gG 1 dry weight). The accumulation of heavy metals in the mangrove tissues took the general trend of root >bark >leaves, the mangrove notwithstanding. It was also observed that cadmium deposition in sediments was comparatively higher than RSV indicating possible cadmium pollution. Generally, accumulation of heavy metals in the mangrove forest of Cross River estuary was within permissible limits. Conclusion: Although the concentrations obtained for the heavy metals studied are generally below documented toxic levels, however, the increasing level of urbanization and industrialization in Calabar municipality and its environs calls for continuous vigilance, surveillance and monitoring of this sensitive and all important ecosystem to protect and ensure that heavy metal pollution is minimal.

Aqueous crude cold-water extract from the fruiting body of the culinary-medicinal oyster mushroom Pleurotus ostreatus was assessed for activity against increased intra-ocular pressure (IOP) in mice. A 0.1% dexamethasone instillation was used to raise the intra-ocular pressure in the animals above the 21-mmHg threshold limit. The extract has intrinsic anti-hypertensive properties that are dose dependent. A comparison analysis indicated that 150 mg/mL of the crude extract produced 57.69% reduction in the intra-ocular pressure, while doses of 100 mg/ mL and 200 mg/mL produced 44.78% and 70.03% IOP reduction, respectively, compared with timolol maleate with 57.69%. The results were significant at 0.05 confidence limit (p < 0.05) when compared to a placebo and therefore support its use for the treatment of increased intra-ocular pressure.

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