This study was undertaken to isolate ligninase-producing white-rot fungi for use in the extraction of fibre from pineapple leaf agriwaste. Fifteen fungal strains were isolated from dead tree trunks and leaf litter. Ligninolytic enzymes (lignin peroxidase (LiP), manganese peroxidase (MnP), and laccase (Lac)), were produced by solid-state fermentation (SSF) using pineapple leaves as the substrate. Of the isolated strains, the one showing maximum production of ligninolytic enzymes was identified to be Ganoderma lucidum by 18S ribotyping. Single parameter optimization and response surface methodology of different process variables were carried out for enzyme production. Incubation period, agitation, and Tween-80 were identified to be the most significant variables through Plackett-Burman design. These variables were further optimized by Box-Behnken design. The overall maximum yield of ligninolytic enzymes was achieved by experimental analysis under these optimal conditions. Quantitative lignin analysis of pineapple leaves by Klason lignin method showed significant degradation of lignin by Ganoderma lucidum under SSF
Padma, Nambisan; Jasmin, Koshy(IJPAES, April 5, 2012)
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Abstract:
Bioethanol is a liquid fuel obtained from fermentation of sugar/starch crops. Lignocellulosic
biomass being less expensive is considered a future alternative for the food crops. One of the main
challenges for the use of lignocellulosics is the development of an efficient pre-treatment process.
Pretreatments are classified into three - physical, chemical, and biological pretreatment. Chemical process
has not been proven suitable so far, due to high costs and production of undesired by-products.
Biologically, hydrolysis can be enhanced by microbial or enzymatic pretreatment. Studies show that the
edible mushrooms of Pleurotus sp. produce several extracellular enzymes which reduce the structural and
chemical complexity of fibre. In the present study, P. ostreatus and P. eous were cultivated on paddy straw.
Spent substrate left after mushroom cultivation was powdered and used for ethanol production.
Saccharomyces sp. was used for fermentation studies. Untreated paddy straw was used as control.
Production of ethanol from P. ostreatus substrate was 5.5 times more when compared to untreated paddy
straw, while the spent substrate of P. eous gave 5 times increase in ethanol yield. Assays showed the
presence of several extracellular enzymes in the spent substrate of both species, which together contributed
to the increase in ethanol yield
Description:
International Journal of Plant, Animal and Environmental Sciences,vol 2,issue 2,april-june 2012
Padma, Nambisan; Renuka, Devi P S; Sabu, A; Sheeja, T E(2013)
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Abstract:
The morphological and biochemical response of calli and seedlings of different
rice cultivars were compared under acid saline conditions. Calli of
both tolerant and sensitive varieties showed severe stress symptoms like
browning and necrosis, but the onset of stress symptoms was delayed in
Pokkali. Seedlings of Pokkali showed minimal stress symptoms in lower
salinities, and curling and senescence of older leaves in higher salinities
although plants revived on amelioration of stress. Seedlings of the other
varieties showed severe stress symptoms even at low salinities and plant
death at higher salinities. Salt stress induced accumulation of the putative
osmoprotectant proline in calli and seedlings of all varieties. Proline accumulation
was higher in sensitive varieties than in Pokkali. These results
indicate that proline accumulation is not directly correlated with salt
tolerance in rice.
Somatic embryos were induced from scutellar callus of immature zygotic embryos of T aestivum cv.
Chinese Spring. Observations on precociously germinating somatic embryos revealed that: (i) In the initial
stages the coleoptile is split, exposes the shoot apex and forms a green trichomatous leafy structure.
In the germinating zygotic embryo, the coleoptile is tubular, (ii) Unlike what has been inferred earlier the
leafy structure is the coleoptile and not the scutellum, (iii) Bipolarity of the embryoid is established later
when root develops at the basal end.
Kerala in south India grows several cash crops such as banana and
pineapple, the crop residues of which are sources of natural fibres that
can be used in hand papermaking. Kerala, however, does not have a
tradition in hand papermaking. The following is an account of an attempt
to popularize the art and craft of hand papermaking among self-help
groups as a means of self-employment and waste utilization, using fibres
extracted from agriwaste and local plants