Treating Bambusa vulgaris with neem seed oil against basidiomycetic biodegradation
A A Erakhrumen
Realising maximum benefits from bamboo stems/culms in Nigeria are presently constrained by their almost non-acceptance for applications in most structural and construction purposes, except in comparatively low quality and some temporary applications, such as scaffolding, owing to their susceptibility to easy destruction by agents of biodegradation as a result of their poor inherent natural durability. Therefore, there is the need for value-addition to this lignocellulosic material using low cost preservatives, particularly the environmentally benign ones, in order to encourage sustainable utilisation for higher valued products and contribute to poverty alleviation in this part of the world. This report is an outcome of an investigation on the efficacy of neem (Azadirachta indica A. Juss) seed oil-treatment for bamboo (Bambusa vulgaris Schrad. ex J.C. Wendl.) against a fungus, also a basidiomycete, known as Pycnoporus sanguineus (L. ex Fr.) Murr. Oven-dried split-bamboo samples conditioned to 11.76% mean moisture content were converted to test specimens for percentage weight loss (PWL) and treated with mechanically extracted neem seed oil (NSO) at two different treatment temperature regimes by completely soaking a set in NSO at ambient room temperature of 25 ± 2oC for 24 hours and soaking the other in NSO at 60oC for 4 hours with untreated samples serving as control. The oil-treated and control samples were initially weighed and subsequently inoculated with cultured P. sanguineus and monitored in an incubating room maintained at ambient temperature of 25 ± 2oC and 65 ± 5% relative humidity for 12 weeks (84 days). After the 84 days incubation period, the test specimens were then reweighed and the PWL determined. Results showed that mean values for PWL was highest for those obtained for control samples (18.21%), comparatively lower for samples soaked in NSO at 25 ± 2oC for 24 hours (5.88%) and lowest for samples soaked in NSO at 60oC for 4 hours (2.21%). Implications of these values were discussed while conclusions and recommendations were based on the outcome of the study.
Keywords: bamboo, neem, oil-treatment, basidiomycetes, environment, weight loss