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Longkong (Aglaia dookkoo Griff.) fruit is prone to rapid pericarp browning and shortened shelf life (<7 days) under prolonged low-temperature storage. This study investigates the effect of an edible coating, comprising carboxymethyl cellulose (CMC) and gelatin in a fixed 3:1 ratio, integrated with various concentrations of melatonin (MT) (0.4, 0.8, and 1.2 mM/L) to mitigate chilling injury in longkong fruit. Coated longkong fruits were stored at 13 °C with 90% relative humidity for 18 days and underwent physicochemical evaluations every three days. Samples coated with CMC-Gel without MT and uncoated fruits were served as controls. The findings indicated that the CMC-Gel-MT coating significantly mitigated pericarp browning, chilling injury, weight loss, and respiration rate increase under extended cold storage conditions. High concentrations of MT (≥0.8 mM/L) in the coating notably inhibited the activities of cellular degrading enzymes such as lipoxygenase and phospholipase D. This inhibition contributed to reduced membrane permeability, lower reactive oxygen species accumulation (H2O2, OH−, O2−), and decreased malondialdehyde levels in the longkong pericarp. Furthermore, the CMC-Gel-MT coating increased the activity of phenylalanine ammonia lyase, leading to an enhancement in phenolic content. Consequently, it improved the fruit's ability to scavenge DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,20-azino-di-3-ethylbenzthiazoline sulfonic acid) radicals. Control samples exhibited high levels of pericarp browning-related enzymes (polyphenol oxidase, peroxidase), whereas CMC-Gel-MT-coated fruits, particularly at higher MT concentrations, showed significant reductions in those enzyme activities. In conclusion, incorporating high concentrations of MT in a CMC-Gel-based edible coating is a promising alternative for mitigating chilling injury in longkong fruit. [ABSTRACT FROM AUTHOR]

Soursop ( Annona muricata L.) leaves are a rich source of bioactive compounds and antioxidant properties. However, they are non-economical and rapidly diminish due to insect damage and biochemical degradation. This study investigates the impact of different drying methods, including tray drying (TD), vacuum drying (VD), and freeze-drying (FD), on the phytochemical and antioxidant properties of soursop leaves at two maturity stages (young (YL) and mature (ML)). By analyzing their proximate composition, mineral content, color characteristics, pH, extraction yield, chlorophyll, ascorbic acid, total phenolics, flavonoids, and antioxidant activities, this study aims to optimize and select the appropriate drying techniques for soursop leaves. Results demonstrate that FD samples achieved the highest preservation of moisture-sensitive bioactive compounds and antioxidant properties followed by VD and TD. FD samples retained higher levels of chlorophyll (10.09-16.88 mg/g), ascorbic acid (15.91-19.89 mg/100g), phenolics (111.98-121.43 mg GAE/g), and flavonoids (68.91-72.45 mg QE/g) exhibited minimal browning and maintained stable pH (6.81-7.01) values. VD effectively reduced moisture content (3.03%) and preserved mineral concentrations, while TD led to significant nutrient loss despite its moisture removal efficiency. Additionally, ML consistently displayed higher nutrient and phytochemical concentrations than YL. This study highlights FD as the optimal method for preserving the health benefits of soursop leaves and suggests VD as a viable alternative when FD is not feasible. These findings are significant for developing cost-effective and efficient preservation strategies, enhancing the economic value of soursop leaves in various applications., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Two novel species of Aspergillus section Nigri from Thai coffee beans are described as Aspergillus aculeatinus sp. nov. and Aspergillus sclerotiicarbonarius sp. nov. Their taxonomic status was determined using a polyphasic taxonomic approach with phenotypic (morphology and extrolite profiles) and molecular (beta-tubulin, internal transcribed spacer and calmodulin gene sequences) characteristics. A. aculeatinus sp. nov. is a uniseriate species with a similar morphology to Aspergillus aculeatus and Aspergillus japonicus, but producing smaller conidia (2-5 microm). A. aculeatinus sp. nov. produced neoxaline, secalonic acid D and F, and aculeacins. A. sclerotiicarbonarius sp. nov. is a biseriate species similar to Aspergillus carbonarius and Aspergillus ibericus, but produces abundant sclerotia and some unique indol-alkaloids. The type strain of Aspergillus sclerotiicarbonarius sp. nov. is CBS 121057(T) (=IBT 28362(T)) and the type strain of Aspergillus aculeatinus sp. nov. is CBS 121060(T) (=IBT 29077(T)).