Influence of Solvent Extract on Properties of Biomaterial PHA Derived from Novosphingobium sp. THA_AIK7

Abstract

Polyhydroxyalkanoates (PHA) production by Novosphingobium sp. THA_AIK7 was investigated in Mineral salt medium (MSM) supplemented with 2% (v/v) of crude  glycerol as a carbon source. The polymer were extracted by sodium hypochlorite and chloroform. Both of extracted films was white, opaque and has a smooth surface. PHA film casting from sodium hypochlorite extraction had bigger pore size than chloroform casted film. The contact angle obtained from polystyrene tissue culture plate (TCP), sodium hypochlorite and chloroform casted film were 78, 81 and 80 degree, respectively. Decomposition temperature (Td), melting temperature (Tm) and crystallization temperature (Tc) were examined against PHB standard. Td of 285, 299 and 298 ° C were acquired from PHB, sodium hypochlorite and chloroform casted film, respectively. Tm value of 170, 167 and 178 ° C and Tc value of 66, 54 and 92 ° C were acquired from sodium hypochlorite,  chloroform and PHB, respectively. Biocompatibility study of PHA film was tested with Vero cell. Vero cells grown on tissue culture plate (TCP) presented typical fibroblast  morphology. However, Vero cells were unable to adhere on sodium hypochlorite casted film and consequently cell lysis was observed. Vero cells could attach on chloroform  casted film but could not develop normal fibroblast appearance and was incapable of proliferating on casted film. The results shown here indicated that the extraction methods were still not proper for biocompatible test. The finding of a suitable method for biomaterial preparation will be done in the next phase.