Effect of Pleurotus ostreatus growth on the Mineral and Proximate Composition of Spent Composted Pycnanthus angolensis and Spondias mombin.







Mushrooms are produced on natural materials taken from agricultural waste and lignocellulosic residues produced through the activities of various industries. After mushroom are harvested, “spent” (used) mushroom substrate become available. The aim of this research was to evaluate the mineral and proximate composition of spent mushroom (Pleurotus ostreatus) substrate (SMS), made from composted  Pycnanthus angolensis (African nut) and Spondias mombin (Hog plum) at ratio 9:1 of wood dust: cow dung .The spent substrates obtained after the 2nd flushes was observed to contain all mineral nutrients inquantities that is of agricultural importance. Protein content increased from 15.11±0.02% to 19.10±0.00% in substrates of P. angolensis wood dust.  While there was increase in protein from 15.18±0.02% to 18.96±0.02% and ash from 3.23±0.01 to 9.91±0.01 in substrate of S. mombin wood dust. There was a general increase in the quantity of mineral element except Fe. There was tremendous increase in the amount of Mn in the spent substrates. The highest was observed in spent substrates of Spondias mombin where Mn increased from 23.30±0.00 to 516.30±0.02%. These results show that SMS should be considered as an alternative for the widely used but expensive inorganic resource in vegetable cultivation.

Key words: Cultivation, mushroom, proximate analysis, mineral substrates