Quality Index Of Chitosan Oligosaccharide Study On The Testing Method And Its Antibacterial Properties

Chito-oligosaccharide has many unique features and wide applications due to its properties such as high water solubility and biological activity. With the wide application and in-depth study of chito-oligosaccharide in the fields of medicine, food, agriculture and cosmetics etc., there is an urgent need to develop an array of quality standards for chito-oligosaccharide production so that its production process and quality control be easy to follow up.This paper investigated the means for testing the qualities of chito-oligosaccharide and determined its physical and chemical characters. In the reference of quality standards of chitin and the market quality requirements for chito-oligosaccharide, combined with its unique properties, we now draw up the quality indicators of chito-oligosaccharide according to its characters, identification, molecular weight, degree of deacetylation, content, moisture, ash content, pH value and heavy metal contents, as well as the means to detect them.In addition, this paper also examined chito-oligosaccharide's roles as antimicrobial reagent and growth-promoter to plants as a kind of biological chemical. In the field trials performed in Jiande and Ningbo, the protective effects of chito-oligosaccharide on Botrytis cinerea Strawberry reached 63.3% and 58.4% respectively. In an indoor bioactivity experiment with 2.8% chito-oligosaccharide solution , the treatment concentrations, 2800, 1400 and 700μg/ml were tested for all the plant diseases, cucumber powdery mildew, cucumber downy mildew and rice sheath blight, and 2800, 1400, 700, 350 and 175μg/ml for Anthrax Melons and melons Botrytis cinerea diseases. All the experiments above were repeated three times, and blank controls were set up for each experiment. The results showed that the protective efficacy of chito-oligosaccharide reached 59.3%, 96.5% and 69.5% respectively on Anthrax melons, melons Botrytis cinerea and rice sheath blight respectively, and among them Specially Botrytis cinerea was the most sensitive disease to chito-oligosaccharide. Besides, chito-oligosaccharide could work as a growth-promoter to strawberry plants. In a concentration ladder used, 10, 25, 50, 75, and 100 mg/l chito-oligosaccharide solution was sprayed three times with the interval of 7 days on strawberry plants. After the third spraying, plant height was measured and it showed that the height averagely increased by 7.8%, 12.6%, 18.9%, 25.4%, 30.2% respectively compared to water controls. These results indicate that chito-oligosaccharide can be used as a kind of biological chemical to protect fruits and vegetables from microbe infection, as well as to help some plants growing.