The lignocellulosic biomass constitutes a major portion of the total carbon fixed by photosynthesis. It consist of cellulose, hemicellulose and lignin that are closely associated with each other constituting cellular complex of the vegetal biomass. However, only a small fraction of this biomass is utilized; most of it is considered waste material. The abundant availability of wastes pose a problem of disposal. Bio-conversion of these renewable wastes would solve pollution problems, and also these organic wastes may become available for soil enrichment. Biodegradation of various agro and agro-industrial wastes could be accomplished through several microorganisms to degrade the lignocellulosic complex. Among these microbes, oyster mushrooms are known to produce extracellular enzymes, such as manganese peroxidase, laccase, lignin peroxidase, and aryl alcohol oxidase, which are capable of degrading this biomass. Hence, biological pretreatment of lignocellulosic biomass with this mushrooms become economically and environmentally attractive.
Cultivation methodology
Various lignocellulosic wastes like sugarcane trash (ST), corn cob (CC), mango sawdust (MSD), paddy straw (PS), waste paper (WP) and wheat straw (WS) were used alone and in combination with wheat straw substrate (1:1) for the cultivation of Pleurotus flabellatus. Among these, traditionally used wheat straw was considered as control. First of all, big sized substrates were chopped into small pieces of about 1 cm length. Thereafter, these were filled separately and in combination in 42×30 cm sized polypropylene bags. These were then washed throughly in fresh water, and pasteurized in a solution of formaldehyde (500 ppm ) and Bavistin (75 ppm ) for 18 h. Under aseptic conditions, these were inoculated with mushroom spawn (@ 5% w/w on dry weight basis) and incubated at 25-30°C for mycelial growth. Once mycelium has completely colonized the substrate, several cuts (1.0-1.5 cm diameter) are made on the mushroom bags. The humidity of room is maintained 80-95% with the help of humidifier. Completely randomized design (CRD) were employed for this study. Yield data were statistically analysed. The critical difference was worked out at five percent probability level.
Mushroom has utilized all substrates and their combinations for their mycelial growth and fruit body development although their magnitude varies among themselves. All the substrate combinations showed quick substrate colonization and early fruit body maturation than individual substrates (Table 1&2). The mycelial growth of mushroom on diverse range of waste indicates that the substrate materials meet all the nutritional requirements desired for fungal growth. It is well established that mushroom growth directly depends upon the amount of nutrients present in the substrate and their availability to fungus.
 |
| Table.1 Effect of substrates on mushroom production |
 |
| Table.2 Effect of substrate combination on mushroom production *Average of three replications |
The mushrooms which grow on waste material are also capable of degrading various substrate components but all of them are not similar in their enzymatic activities and therefore, they show preference for specific substrate. Due to this, yield and biological efficiency varies among the substrates and their combinations. Every substrate mixed with wheat straw showed better response than individual form (Table 1&2). It illustrates that better yield can be achieved from low yielding substrates by using substrate combination strategy. In our investigation, paddy straw was proved high yielding substrate in both the form. It was due to high cellulose content in straw substrate that would result in enhancing cellulase enzyme production. This enzyme is positively correlated with yield of mushroom.
 |
| Fruiting of Pleurotus flabellatus on various wastes -Sugarcane trash (ST), Corn cob (CC), paddy straw (PS), Waste paper (WP), CC+WS, MSD+WS, PS+WS, WP+WS and Wheat straw(WS) |
0 comments:
Post a Comment