The use of hazardous formalin in increasing shelf life of fruits and protecting them from microbial decay by unscrupulous traders is a big health concern for the consumers in Bangladesh. Chitosan is a natural biopolym...The use of hazardous formalin in increasing shelf life of fruits and protecting them from microbial decay by unscrupulous traders is a big health concern for the consumers in Bangladesh. Chitosan is a natural biopolymer produced from the exoskeletons of shrimp and crab, which slows antimicrobial activities and induces immunity of plants against microbial pests. This study aimed to evaluate the efficacy of chitosan on the shelf life extension of some local ripened fruits compared to untreated control. Three doses of chitosan solution viz. 0, 500 and 1000 ppm were sprayed in alternate day on banana (cvs. Shabri and Champa), strawberry, tomato, and oranges. It revealed that chitosan extended shelf life of all fruits by delaying the decay;however, level of protection varied in different kinds of fruits as well as in doses of the chitosan used. Among the tested fruits, decay of tomatoes was most delayed by chitosan. Spraying of both 500 and 1000 ppm of chitosan equally protected 100% decay in tomatoes until 8 days of treatments at room temperature. More than 80% protection of other fruits viz. banana, orange and strawberries by chitosan were recorded at 8, 8 and 4 day after treatment, respectively, which were remarkably higher than the untreated control. Interestingly, 500 ppm of chitosan spray gave better protection than 1000 ppm in all the tested fruits. These results suggest that lower doses of chitosan can be utilized as a natural preservative of fruits alternative to hazardous formalin. A further study with higher number of fruits, and at varying temperature and chitosan doses are needed for recommending it for practical application as a fruit preservative.展开更多
Quantitative analysis of saccharin in preserved fruits was performed by High Performance Liquid Chromatography （HPLC）. The separation was observed on a reversed phase ODS C）8 column （4.6 × 250 mm）. Mobile ph...Quantitative analysis of saccharin in preserved fruits was performed by High Performance Liquid Chromatography （HPLC）. The separation was observed on a reversed phase ODS C）8 column （4.6 × 250 mm）. Mobile phase system consisted of ammonium acetate buffer： Methanol （60：40 v/v） at a flow rate of 1.0 mL.min^-1, and UV detector was set at 235 nm. The calibration curve of saccharin was linear in the concentration range between 1 to 100 mg·L^-1）, while the detection limit of saccharin was found to be 0.08 mg.L^-1. The mean value of recovery was 98.24% with standard deviation of0.32% （n=12）. The proposed method was successfully applied to determine the amount of saccharin in 12 preserved fruits, commercially available in Chiang Mai local markets. The results showed that the saccharin contents were found in the range of 6.22-78.60 mg.kg^-1.展开更多
文摘The use of hazardous formalin in increasing shelf life of fruits and protecting them from microbial decay by unscrupulous traders is a big health concern for the consumers in Bangladesh. Chitosan is a natural biopolymer produced from the exoskeletons of shrimp and crab, which slows antimicrobial activities and induces immunity of plants against microbial pests. This study aimed to evaluate the efficacy of chitosan on the shelf life extension of some local ripened fruits compared to untreated control. Three doses of chitosan solution viz. 0, 500 and 1000 ppm were sprayed in alternate day on banana (cvs. Shabri and Champa), strawberry, tomato, and oranges. It revealed that chitosan extended shelf life of all fruits by delaying the decay;however, level of protection varied in different kinds of fruits as well as in doses of the chitosan used. Among the tested fruits, decay of tomatoes was most delayed by chitosan. Spraying of both 500 and 1000 ppm of chitosan equally protected 100% decay in tomatoes until 8 days of treatments at room temperature. More than 80% protection of other fruits viz. banana, orange and strawberries by chitosan were recorded at 8, 8 and 4 day after treatment, respectively, which were remarkably higher than the untreated control. Interestingly, 500 ppm of chitosan spray gave better protection than 1000 ppm in all the tested fruits. These results suggest that lower doses of chitosan can be utilized as a natural preservative of fruits alternative to hazardous formalin. A further study with higher number of fruits, and at varying temperature and chitosan doses are needed for recommending it for practical application as a fruit preservative.
文摘Quantitative analysis of saccharin in preserved fruits was performed by High Performance Liquid Chromatography （HPLC）. The separation was observed on a reversed phase ODS C）8 column （4.6 × 250 mm）. Mobile phase system consisted of ammonium acetate buffer： Methanol （60：40 v/v） at a flow rate of 1.0 mL.min^-1, and UV detector was set at 235 nm. The calibration curve of saccharin was linear in the concentration range between 1 to 100 mg·L^-1）, while the detection limit of saccharin was found to be 0.08 mg.L^-1. The mean value of recovery was 98.24% with standard deviation of0.32% （n=12）. The proposed method was successfully applied to determine the amount of saccharin in 12 preserved fruits, commercially available in Chiang Mai local markets. The results showed that the saccharin contents were found in the range of 6.22-78.60 mg.kg^-1.
