Aims: To document the amino acid content of six wild edible mushrooms - Lentinus squarrosulus Mont., Auricularia auricular-judae (Bull.) Wettst., Mycetinis copelandii (Desjardin) A.W. Wilson & Desjardin, Baeospora myosura (Fr.) Singer, Pleurotus ostreatus (Jacq. ex. fr) Kummer and Volvariella volvacea (Bull. ex. Fr.) Singer - found in southern Cross River State, Nigeria. Place and duration of study: Department of Plant and Ecological Studies, University of Calabar, Cross River State, Nigeria, between May 2018 and August 2018. Methodology: The amino acids content of these mushrooms were quantitatively estimated. The samples were obtained and analyzed for amino acids on dry weight basis using standard methods. Results: The amino acid analysis quantitatively estimated the alanine, arginine, aspartic acid, cystine, glutamic acid, glycine, histidine, Isoleucine, leucine, lysine, methionine, norleucine, phenylalanine, proline, serine; threonine; tryptophan; tyrosine and valine component of the mushroom samples. All the mushrooms studied contained nine essential, five conditionally essential and four non-essential amino acids with glutamic acid as the most predominant (values ranging from 6.66 to 17.26g/100g protein). Cysteine (0.30-0.48g/100g protein) and methionine (0.64-1-1.7g/100g protein) were the lowest in concentration. The concentrations of five of these essential amino acids phenylalanine (3.55 mg/100g protein), valine (3.62 mg/100g protein), threonine (3.39 mg/100g protein), tryptophan (1.58 mg/100g protein), and lysine (3.23 mg/100g protein) in P. ostreatus were significantly (P≤0.05) higher than found in the other mushrooms. For the nonessential and conditionally essential amino acids, the concentrations of arginine (6.02 mg/100g protein), aspartic acid (6.88 mg/100g protein), cysteine (0.48 mg/100g protein), glutamine (17.26 mg/100g protein) and glycine (2.61 mg/100g protein) in P. ostreatus were significantly higher (P≤0.05) than found in the other mushrooms. Conclusion: This information reveals that mushrooms are potential sources of quality protein with substantial proportion of essential amino acids indicating they can play a significant role in the fight against malnutrition.

Pleurotus ostreatus, an edible mushroom is an essential food product. Recognised as one of the cheapest sources of proteins, their high nutritional and anti-nutritional properties are of immense importance to humans. The present study evaluated the effect of sawdust and dried plantain leaves on the growth and yield of Pleurotus ostreatus. Sawdust and dried plantain leaves were composted into seven substrates; as single substrates and at different combinations. The composted substrates include sawdust 100 % (M0), Dry plantain leaves 100% (M1), Dry plantain leaves + sawdust at the ratio of 1:4 (M2), 2:3 (M3), 3:2 (M4), 1:1 (M5) and 4:1(M6). Growth parameters of interest assessed flush include mycelia running rate (MRR), area of pileus, length of the stipe, the girth of the stipe, fresh weight and dry weight, number of fruit body, total yield and biological efficiency. At the end of the three weeks spawn running period, M0 was overall best in supporting mycelia running rate with a mean MRR of 16.00 cm. M1 substrates produced mushroom with longer and bigger stipes (7.17 cm) at the first flush. A higher number of fruit bodies (82.66), total yield (130.35 g), and biological efficiency (43.45 g) were all seen in M0 substrates. Sawdust at 100 % (M0) proved to be the best substrate for the cultivation of Pleurotus ostreatus.

Aims: To investigate the growth response of Pleurotus ostreatus, a wood-rotting fungus, to different growth substrates [Sawdust (SD), dry banana leaves (BL) and a combination of both BL and SD (BLSD)] amended with waste [salon effluent (SE) and spent calcium-carbide (SC)]. Place and duration of study: Department of Plant and Ecological Studies, University of Calabar, Cross River State, Nigeria, between May 2015 and August 2015. Methodology: Amendments were applied to growth substrates at different levels of concentration as follows: 0 ml and 0 g, 5 ml and 5 g, 10 ml and 10 g, 15 ml and 15 g per kg substrate. Mature mushrooms were harvested and assessed on the following parameters; number of fruit bodies, fresh weight, dry weight, length of stipe, girth of stipe, pileus area using conventional method. Results: Number of fruitbodies, fresh weight, dry weight and stipe length increased with increase in concentration of additives. Best performances of these growth parameters were obtained at 15 g/kg and 15 ml/kg concentration. The highest number of fruitbodies (with a peak mean value of 28.42 fruitbodies at 15 g/kg concentration), highest value of fresh weight and dry weight were observed in SD. The longest stipe length, largest stipe girth and pileus area were observed in BLSD, though it exhibited least performances in other growth parameters. BLSD amended with salon effluent produced mushrooms with the largest pileus area (with a peak mean value of 53.8 cm2 at 15ml concentration) compared to the other substrates. Conclusion: This study reveals that all growth parameters of P. ostreatus assessed were positively influenced by all the levels of amendments on the substrates used in this study. Therefore, these wastes could be used to increase the yield of P. ostreatus and possibly remediate sites polluted by these wastes.

This study was carried out to assess the capacity of Pleurotus ostreatus to bio-accumulate trace elements from petroleum product-amended growth substrates. The test mushroom was grown on two (2) substrates namely, banana leaves (BL) and sawdust (SD) substrates which were amended with (5 ml, 10 ml and 15 ml) of crude oil, diesel and spent engine oil separately. The fruit-bodies harvested from the substrates were subjected to analysis for trace elements. The ten elements of interest were cadmium, copper, chromium, cobalt, manganese, zinc, iron, lead, mercury and nickel. All the elements analyzed for were found in reasonable levels in the mushroom except for mercury (Hg) which was below detectable levels (BDL). The highest amounts of elements were detected in mushrooms from crude oil-based substrates with zinc at the top of the list with 51.19 mg/100g, Iron (32.40 mg/100g) and manganese (28. 36 mg/100g) were next. Less than one milligram (1mg) of copper was bio-accumulated per 100g of the edible portion. In spent oil-and diesel-amended substrates, zinc was still the highest bio-accumulated with values of 33.00mg/100g and 27.22mg/100g respectively. About 18.9mg/100g and 13.92mg/100g of manganese were extracted and retained the mushroom fruit-body harvested from diesel and spent oil-rich substrates respectively. The amount of iron found in the test mushroom was, however, lower (14.93mg/100g) in fruit-bodies harvested from spent oil when compared with those (21.20mg/100g) from dieselamended substrates while copper bio-accumulated more in fruit-bodies obtained from spent oil than those from diesel-rich substrates. The levels of these important trace elements reported in some commonly consumed plants and animal products are low. The use of mushrooms to extract useful trace elements from amended growth substrates is here presented as an alternative to inorganic food supplements for the treatment of nutrition-related illnesses.

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