Antibacterial activity of anti-acne preparation of Polysaccharide gel from durian fruit-hulls

Abstract

Polysaccharide gel (PG) from durian fruit-hulls at concentration 2.5% w/v have been demonstrated bactericidal activity, the present studies was to determine factors effecting the viscosity of PG. Divalent cations showed high effect on increasing PG viscosity. Organic solvents and humectants at higher concentration than 15% increase PG viscosity but paraben shows less effect. Phosphate buffer increases PG viscosity greatly, whereas citrate buffer slightly increases viscosity of PG dispersion. Screening test for antimicrobial activity of betel vine oil against 10 bacteria and 2 fungi was performed. The susceptibility test was determined by agar diffusion method. The zones of inhibition were obtained at the lowest concentration 0.08% v/v of betel vine oil against bacteria, Micrococcus luteus ATCC 9341, Bacillus subtilis ATCC 6633, Proteus vulgaris ATCC 13315, Pseudomonas aeruginosa ATCC 9721; and fungus, Saccharomyces cerevisiae ATCC 9763; inhibition zone against Candida albicans ATCC 10230 was at 0.16%; and against Propionibacterium acnes ATCC 6919, Staphylococcus aureus ATCC 6538P, Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 25922, Salmonella typhimurium ATCC 14028 and Klebsiella pneumoniae ATCC 10031 was at 0.31%. Broth macrodilution test was used to determine a quantitative antimicrobial activity of betel vine oil. Minimal inhibitory concentrations (MICs) of betel vine oil against tested microorganisms were in ranges 0.010 to 0.078% (v/v) and minimal bactericidal concentrations (MBCs) were at 0.020 to 0.156%. Antimicrobial PG gel preparations were formulated together with betel vine oil in order to obtain broader antimicrobial activity of the products. The formulation contained betel vine oil gave a satisfactory clear gel products. After stability tested by freeze-thaw cycle for 6 cycles, the products remain unchanged and the gel characteristics was the same as after freshly prepared. The antibacterial potential of the antimicrobial PG gel finished products which composed of PG and 1 or 2% betel vine oil was explored. The susceptibility test of the products was evaluated by agar diffusion method and broth microdilution method against bacteria, S. epidermidis, S. aureus and P, acnes, which cause skin infection and pimples. The results indicated that both antimicrobial PG gel products exhibited antibacterial activity against target bacteria.