Effects Of Crude Extracts From Aloe On Postharvest Fresh-keeping And The Mechanism Of Bio-control Research

The objective of the present work was to evaluate the protective effects of Aloe extractson Red Fuji apple fruit decay caused by Botrytis cinerea, as well as the effect of Aloe extractson the disease resistance ability in Red Fuji apple fruit.1. In ex-vivo, the results of the antibacterial activity of aloe extract: aloe juice and crudeextracting from aloe vera have a certain inhibition effect on three pathogenic fungi(gray mold,penicillium, anthrax). The antibacterial rate of aloe vera juice against grey mold, penicillium,anthrax inhibition rate were34.39%,25.43%,29.03%respectively, but compared to inhibiteffect is not obvious; Crude extracting from aloe vera on three kinds of pathogenic bacteriainhibition rate are97.85%,50.9%and97.85%respectively, compared with controls,antibacterial effect is remarkable.2. In vitro, the results showed that Aloe extract flavonoid significantly decreased theincidence of gray mold rot in Red Fuji apple fruits, and effectively suppressed the expansionof lesions in vivo. After four-day storage, the gray mold rot incidence of Red Fuji apple fruitsthat were treated with the concentration of Aloe extract flavonoid (0.035g/L,0.050mg/L)was73%and53%respectively, which was significantly lower than that of the control (93%)(P <0.05). The effect of control grey mold is closely related to the quality of the crude extractconcentration. The best concentration of flavonoids of mass concentration is0.05g/L.3. The determination of crude extracting from aloe vera effects on fruit quality: Theresults showed that aloe crude extract treatments could prevent the apples weight loss，andREC(relative electric conductivity)rising，maintain the low respiration rate and the release rateof ethylene， and also delay the degeneration of total soluble solid sand titratableacidity．Thus, aloe crude extract processing can well inhibit Fuji apple physiological changesduring storage. The best result of treatments was received from the treatmentwith0.05concentration of aloe crude extract which effectively delay ripening of ageingprocess of fruit．4. Aloe extract flavonoid increased the activity of peroxidase (POD), polyphenol oxidase(PPO), phenylalanine ammonia enzyme (PAL), chitinase (CHT), and β-1,3-glucanase (GLU). Phenolics content also increased significantly.