PRELIMINARY STUDY ON POTENTIAL EDIBLE COATINGS DERIVED FROM CARBOXYL METHYLCELLULOSE AND FUNGI CULTURED METABOLITES ON THE SHELF-LIFE EXTENSION OF SWEET-ORANGE (CITRUS SINENSIS)

This study focused on assessing the potential of formulated edible coatings derived from a metabolite of Trichoderma viride and Penicillium chrysogenum, combined with carboxyl methylcellulose (CMC) on the postharvest storage quality of orange fruits. The cultured metabolite of fungal bioagents combined with CMC, as well as glycerol (plasticizer), inadequate solution ratio based on wettability, was evaluated for microbiological quality and shelf-life extension of sweet orange. Thereafter, ascorbic acid, total soluble solids, pH, percentage weight loss, among other parameters were assessed for 7 weeks. The results of the study revealed that the pH of CMC + Trichoderma viride and CMC + P. chrysogenum coatings had 3.8 ± 0.02 and 3.17 ± 0.06 respectively, while it was reported 2.90 ± 0.04 for uncoated treatment. Also, the ascorbic acid and total soluble solids of the edible coated oranges were higher than the control. In addition, the percentage of weight loss was higher in the uncoated control compared to the potential edible coated oranges. Further, the microbial load count of the potential edible-coated oranges was less compared to the un-coated oranges. In conclusion, this formulated potential edible coating could be further improved upon and optimized for use in prolonging the storage of sweet oranges

AMINO ACID COMPOSITION AND ANTI-TYROSINASE ACTIVITY OF METABOLITES FROM EDIBLE Pleurotus SPECIES FOR THEIR NUTRITIONAL AND THERAPEUTIC POTENTIAL

Mushrooms are being extensively researched due to their nutritional value and medicinal importance. The genus Pleurotus is the second most cultivated mushroom and is known for its high nutritional value, therapeutic properties, taste, flavor, as well as their application in biotechnology and environmental study. Also, tyrosinase is prevalent in most living organisms. The enzyme catalyzes the oxidation of monophenols to ortho-quinones in a two-step reaction process. This study was aimed to assess the amino acid composition and anti-tyrosinase activity of metabolites obtained from edible Pleurotus species. Assessment of the nutritional content and inhibitory studies of mushroom tyrosinase produced from four Pleurotus strains was carried out using high-performance liquid chromatography (RP-HPLC). The results of the study showed that seventeen different amino acids were identified in the crude and partially purified protein metabolites. Also, the crude extract metabolite had the highest quantity of amino acids than the partially purified. The highest and lowest amino acids value Glutamic acid (1343.26 µmol/mL) and valine (0.34 µmol/mL). The anti-tyrosinase inhibition studies of the four Pleurotus strains showed varying results from significantly inhibitory effects to slightly inhibitory effects on mushroom tyrosinase. The highest inhibition was 14.86% (Pleu-W), while the lowest inhibition was 51.42% (Plof-30) respectively. The high point of this study is that the Pleurotus species contains a significant number of amino acids and also, they possess good anti-tyrosinase activity. Therefore, these are a good source of nutritional and therapeutic metabolites and these can be explored further for their nutritional and medicinal importance to man

Effect of soil type on chemical composition and antioxidant properties of Solanum nigrum (L.) shoot oil extracts

Purpose: To investigate the effect of different soil textures on chemical composition and antioxidant properties of essential oils from Solanum nigrum. Methods: Four soils of differing texture were formulated from soil under fallow to cultivate S. nigrum in a glasshouse. Essential Oil was extracted from fresh shoots by solvent-free microwave extraction (SFME) and analysed using gas chromatography-mass spectrometry (GC-MS). Antioxidant properties were assayed (DPPH) and ABTS Results: GC-MS profiling revealed variations in the quality index (QI), number of chemical constituents and antioxidant results of S. nigrum oil. Geraniol and citronellol were the two principal components. The highest activity of the antioxidant was found in plants cultivated on clay loam soil. Fifty percent (50%) Inhibitory Concentration (IC50) ranged from 1.196 to 1.594 μg/mL and 0.067 to 3.59 μg /mL in DPPH and ABTS assays, respectively. Conclusions: This research work indicates that soil texture influences the oil quality, quantity and chemical composition of oil extracted from S. nigrum shoots. Essential oil extracts from S. nigrum grown on clay loam soils recorded the highest antioxidant properties