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Management of anthracnose caused by Colletotrichum spp. is the most important issue for the tropical fruit industry because of resulting financial losses. Antifungal effects of gum arabic (GA) (10%), lemongrass oil (LG) (0.05%), cinnamon oil (CM) (0.4%), and their combinations were investigated in vitro and in vivo for controlling postharvest anthracnose of banana and papaya. LG at 0.05% and 0.4% CM showed fungicidal effects against Colletotrichum musae and Colletotrichum gloeosporioides, causal organisms of banana and papaya anthracnose, respectively. GA alone did not show any fungicidal effects while the combination of 0.05% LG and 0.4% CM with Ten percent GA alone showed more fungicidal effects. However, potato dextrose agar (PDA) medium modified with 10% GA combined with 0.4% CM showed the most promising results among all treatments against C. musae and C. gloeosporioides in suppressing the mycelial growth (73.4%) and (70.0%) and spore germination inhibition (88%) and (85%), respectively. In vivo studies also revealed that 10% GA combined with 0.4% CM was the optimal concentration in controlling decay (80%) and (71%), showing a synergistic effect in the reduction of C. musae and C. gloeosporioides, respectively, in artificially inoculated bananas and papayas. The results regarding quality evaluation also confirmed the efficacy of 10% GA combined with 0.4% CM coatings since ripening was significantly delayed, in terms of percentage weight loss, fruit firmness, soluble solids concentration and titratable acidity. The results suggest the possibility of using 10% gum arabic combined with 0.4% cinnamon oil as a biofungicide for controlling postharvest anthracnose in major tropical fruit such as banana and papaya.

a b s t r a c tEffect of gum arabic (GA) 10% and calcium chloride (CA) 3% on the physiological and biochemical properties of mango (Mangifera indica L. CV. Choke Anan) fruits stored at 6 ± 1 • C and 90 ± 3% relative humidity for 28 days and then transferred to 25 ± 2 • C for 5 days shelf life were investigated. Significant (P ≤ 0.05) differences were observed in fruits treated with GA 10% and CA 3% as compared to control. The combined treatment of CA 3% + GA 10% significantly alleviated the increase in decay incidence. Furthermore, GA 10% alone or combined with CA 3% effectively reduced weight loss, color changes, soluble solid concentration, respiration rate, ethylene production and maintained high firmness, titratable acidity and ascorbic acid. The result of transmission electron microscopy revealed that these treatments also protected the ultrastructure of mitochondria. These results suggest that application of GA 10% coating combined with CA 3% might be a simple and effective technique for preserving mango fruit quality during low temperature storage.

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The present research was conducted to discover antimicrobial compounds in methanolic leaf extracts of Jatropha curcas and Andrographis paniculata and ethanolic leaf extract of Psidium guajava and the effectiveness against microbes on flower preservative solution of cut Mokara Red orchid flowers was evaluated. The leaves were analyzed using gas chromatography-mass spectrometry. A total of nine, 66, and 29 compounds were identified in J. curcas, P. guajava, and A. paniculata leaf extracts, with five (88.18%), four (34.66%), and three (50.47%) having unique antimicrobial compounds, respectively. The experimental design on vase life was conducted using a completely randomized design with 10 replications. The flower vase life was about 6 days in the solution containing the P. guajava and A. paniculata leaf extracts at 15mg/L. Moreover, solution with leaf extracts of A. paniculata had the lowest bacterial count compared to P. guajava and J. curcas. Thus, these leaf extracts revealed the presence of relevant antimicrobial compounds. The leaf extracts have the potential as a cut flower solution to minimize microbial populations and extend flower vase life. However, the activities of specific antimicrobial compounds and double or triple combination leaf extracts to enhance the effectiveness to extend the vase life need to be tested.