The Use of the Valuable Oyster Mushroom, Pleurotus sajor-caju, for Conversion of Waste Materials Produced from Seaweed and Brewing Industries: Preliminary Investigations

摘要

Preliminary tests on growing the oyster mushroom, Pleurotus sajor-caju on commonly available wastes generated by the seaweed and brewing industries were conducted. Various combinations of these wastes and scrub grass were used. The fungus grew well, vegetatively on all combinations of substrate except pure spent barley, but was slower on substrates with higher salt concentrations. Fruiting (mushroom production) was best on those substrates containing kelp rather than Gracilaria gracilis, probably due to the high salt content of the G. gracilis. No mushrooms were produced on 100 percent seaweed substrates probably due to nutrients being too readily available. For the most part, Namibia has a semiarid to desert environment, consequently terrestrial biological production is low and therefore organic wastes from agriculture and the natural environment are not abundant. In contrast, the marine environment of Namibia is extremely productive and supports a valuable fishing industry, which is one of the mainstays of the economy. On the coast of Namibia seaweed growth rates are amongst the highest in the world (1, 2) and this is only now being taken advantage of by the local seaweed industry. This industry collects beach-cast seaweeds for agar production, fertilizers, and soil conditioners and also cultivates the agarophyte (red seaweed) Gracilaria gracilis on floating systems. Inevitably, not all of the raw material collected and grown is suitable for production and so, becomes waste.