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Abstract: Chitosanase (EC3.2.1.132) catalyzes the hydrolysis of β-1,4-glycosidic bonds in chitosan, converting it into chitooligosaccharides, which exhibit versatile application potentials in food, pharmaceutical, and agricultural areas. In this paper we present a new inducible chitosanase, isolated, and purified from a bacterial culture medium of Streptomyces roseolus DH by precipitation with ammonium sulfate and combined column chromatographies. The SDS–PAGE results show its molecular mass is around 41kDa, with a purity of more than 95%. The purified chitosanase exhibits optimum activity at 50°C, pH 5.0. It is stable between 30 and 60°C and at pH values between 5 and 7. It shows the highest activity towards colloidal chitosan and breaks down glycol chitosan and glycol chitin weakly. The enzyme is significantly inhibited by Cu2+, Co2+, Mn2+, Zn2+, and EDTA, but slightly activated by Mg2+. Further action mode analysis based on chitosan oligomers and a polymer reveals that the chitosanase could split chitooligosaccharides with degree of polymerization (DP) >4 and chitosan in an endolytic manner. The resultant hydrolytes are mainly chitotrisaccharides, indicating it is suitable for the uniform bioconversion of chitosan and its derivatives with high efficiency. [Copyright &y& Elsevier]

Bamboo Winding Composite Pipe (BWCP) is a novel product that reintroduces and modernizes the use of bio-based pipes in below ground water reticulation infrastructure, and can replace PVC and concrete pipe in many low to medium pressure water service and sewerage applications. Pipes are built to accommodate service pressures of up to 1.6 MPa, with a long-term hydrostatic pressure projection of 50 years. Maximum burst pressures are up to 3.75 MPa. The new technology overcomes the structure and performance limitations of earlier wood veneer-based hollow tubes by encasing helically wound layers of thin but strong bamboo sliver curtains in a protective matrix of gauze wrap, thermosetting resin and powdered bio-filler. Bamboo has unique and very high tensile strength fiber and aligning this around the pipe circumference produces a high strength, ductile and pressure resistant pipe. This fabrication technology is extremely versatile, producing pipes ranging from 150 mm to 5000 mm in diameter with a wall thickness of 9 mm–38 mm for a wider range of applications including non-round shells for train cars and modular housing construction. An integrated supply chain model of satellite fabrication sites for curtain winding elements at the source and centralized manufacturing of pipes close to market locations can provide employment and income for remote villages and increase transportation efficiency. BWCP is energy efficient, requiring less than a quarter of the energy of steel pipes per meter. It presents a significant potential for carbon storage over time, holding an estimated 0.5 t of sequestered atmospheric CO 2 per t of pipe manufactured. • Development and testing of novel bamboo-based pipe technology. • Can replace significant quantities of concrete and plastic water pipes. • Energy efficient, carbon sequestration and below ground storage. • Sustainable, localized element fabrication close to bamboo source. • Further applications as utility tunnels, poles, train cars, modular housing. [ABSTRACT FROM AUTHOR]