Postharvest melatonin treatment reduces chilling injury in sapota fruit.

BACKGROUND: Sapota is a popular tropical fruit characterized by a very short postharvest life. Low-temperature storage prolongs postharvest life of sapota fruit, but chilling injury symptoms can develop if the storage temperature is less than 14 °C. There have been no reports on the effects of postharvest melatonin application on the development of chilling injury in sapota fruit during cold storage. The objective of this study was to investigate the effects of different concentrations of postharvest melatonin application (0, 30, 60 and 90 µmol L-1 ) during cold storage (8 °C) for up to 30 days with an additional 1-day shelf life at ambient temperature. RESULTS: All melatonin treatments reduced chilling injury symptoms, reduced electrolyte leakage, malondialdehyde (MDA) content, H2 O2 and superoxide anion (O2 - ), and increased proline content and the activity of superoxide dismutase (SOD), catalase (CAT) and γ-aminobutyric acid (GABA), and reduced the activities of phospholipase D (PLD) and lipoxygenase (LOX) compared to the control. CONCLUSION: Postharvest melatonin treatment could be a useful strategy for reducing chilling injury during cold storage and transport of sapota fruit. The results indicate that melatonin reduces chilling injury of sapota fruit through maintaining membrane integrity, SOD and CAT activities, and reducing PLD and LOX activities. © 2019 Society of Chemical Industry.

Pharmacobotanical study of Manilkara zapota (L. ) P. Royen (Sapotaceae)

Manilkara zapota (L.) P. Royen, popularly known as sapoti or sapota (sapodilla), is a tree bearing an important fruit, in addition to different parts of the plant being widely used in folk medicine in the management of inflammation, pain, fevers, coughs, diarrhea, dysentery, among other ailments. This study aimed to conduct a pharmacobotany standardization study of M. zapota. Semi-permanent slides, containing transversal sections of stem, petiole, leaf blade and fruit; and paradermic sections of leaf blade were prepared, and analyzed by light microscopy. Histochemical tests were also performed in cross-sections of the leaf blade. Microscopic analysis allowed the identification of important elements in the diagnosis of the species; while the use of histochemical techniques on the leaf blade showed evidence of the presence of phenolic compounds, tannins, triterpenes and steroids, lipophilic compounds, starch, lignin and calcium oxalate crystals. The results presented contributed to characterization of the species.