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In recent years, there has been an increase in the study of phytomelatonin. Having numerous functions in animals, melatonin produced by plants (phytomelatonin) is also a multi‐regulatory molecule with great potential in plant physiology and in mitigating abiotic stresses, such as drought, salinity, chilling, heat, chemical contamination, and UV‐radiation stress. This review highlights the primary functions of phytomelatonin as an anti‐stress molecule against abiotic stress. We discuss the role of phytomelatonin as a master regulator, oxidative stress manager, reactive oxygen species and reactive nitrogen species regulator, and defense compounds inducer. Although there exist a handful of reviews on the crosstalk of phytomelatonin with other signaling molecules like auxin, cytokinin, gibberellin, abscisic acid, ethylene, nitric oxide, jasmonic acid, and salicylic acid, this review looks at studies that have reported a few aspects of phytomelatonin with newly discovered signaling molecules along with classical signaling molecules with relation to abiotic stress tolerance. The research and applications of phytomelatonin with hydrogen sulfide, strigolactones, brassinosteroids, and polyamines are still in their nascent stage but hold a promising scope for the future. Additionally, this review states the recent developments in the signaling of phytomelatonin with nitrogen metabolism and nitrosative stress in plants. [ABSTRACT FROM AUTHOR]

The best strategy to extend the shelf life of fresh horticultural produce is to keep it at a low temperature. However, storing fruits and vegetables at a temperature lower than their recommended storage temperature and above the freezing point for a prolonged time leads to the development of chilling injury (CI). Melatonin (MT) being a versatile biological signal has been reported to possess antioxidant properties that aid in mediating stress response and extending the postharvest storage life of horticultural crops. Among CI‐induced mechanisms, MT substantially reduces oxidative stress by elevating the reactive oxygen species scavenging and triggering the phenol accumulation in association with 2, 2‐diphenyl‐1 picryl hydrazyl scavenging activity. Besides, MT increases intracellular energy by maintaining a proper ratio of unsaturated to saturated fatty acid and improving cellular fluidity. Additionally, MT regulates arginine metabolism by maintaining the γ‐aminobutyric acid synthesis. Furthermore, MT encodes the mitogen‐activated protein kinases, and calcium‐dependent protein kinases cascade and acclimate to cold stress by activating C‐repeat binding factors and helps in maintaining postharvest quality. This review reports the recent progress of MT‐induced physiological, biochemical, and molecular mechanisms for enhancing chilling tolerance, which can elevate the marketability and earnings from postharvest horticultural crops. Core Ideas: Chilling injury during storage is a common problem in fruits and vegetables.Melatonin plays a vital role in mitigating postharvest chilling injury.Melatonin increases intracellular energy by maintaining a proper ratio of unsaturated to saturated fatty acid.Melatonin imparts chilling tolerance via reactive oxygen species, arginine pathway, GABA, and proline accumulation. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: A randomized block design experiment was performed to investigate the influence of drying on the physical, chemical and nutritional quality attributes of five prominent cultivars of India under sun drying (SD) (mean temperature 35.5 °C, average daily radiation 5.26 kW h m−2 and mean relative humidity 73.66% RH), hot air drying (HD) at 65 °C, microwave vacuum drying (MVD) (800 W, 5 kPa) and freeze drying (FD) (−50 °C, 5 kPa). Water activity, pH, total phenolic content (TPC), ascorbic acid (AA), capsaicin, β‐carotene, color and Scoville heat unit were studied. RESULTS: TPC, AA, capsaicin content, β‐carotene, color and water activity were significantly affected by the drying method. FD was observed to be most efficient in minimizing the loss of color, capsaicin and β‐carotene. The hotness of analyzed samples decreased in the order ‘Bird's Eye’ > ‘Sannam S4’ > ‘CO‐4’ > ‘PLR‐1’ > ‘PKM‐1’ among the studied cultivars, and FD > MVD > HD > SD among the drying methods. CONCLUSION: The FD method was observed to be the most efficient drying method for retaining capsaicin content over other drying methods (SD, HD, MVD), whereas MVD was found to be most efficient in minimizing the loss to nutritional attributes for all five pepper cultivars. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: Fruits and vegetables are the most utilized commodities among all horticultural crops. They are consumed raw, minimally processed, as well as processed, due to their nutrients and health‐promoting compounds. With the growing population and changing diet habits, the production and processing of horticultural crops, especially fruits and vegetables, have increased very significantly to fulfill the increasing demands. Significant losses and waste in the fresh and processing industries are becoming a serious nutritional, economical, and environmental problem. For example, the United Nations Food and Agriculture Organization (FAO) has estimated that losses and waste in fruits and vegetables are the highest among all types of foods, and may reach up to 60%. The processing operations of fruits and vegetables produce significant wastes of by‐products, which constitute about 25% to 30% of a whole commodity group. The waste is composed mainly of seed, skin, rind, and pomace, containing good sources of potentially valuable bioactive compounds, such as carotenoids, polyphenols, dietary fibers, vitamins, enzymes, and oils, among others. These phytochemicals can be utilized in different industries including the food industry, for the development of functional or enriched foods, the health industry for medicines and pharmaceuticals, and the textile industry, among others. The use of waste for the production of various crucial bioactive components is an important step toward sustainable development. This review describes the types and nature of the waste that originates from fruits and vegetables, the bioactive components in the waste, their extraction techniques, and the potential utilization of the obtained bioactive compounds. [ABSTRACT FROM AUTHOR]

Pomegranate is a subtropical and tropical fruit of great importance from a health point of view. Despite increasing consumer awareness of the health benefits of pomegranate, consumption of the fruit is still limited owing to poor postharvest handling, storage recommendations, short shelf life and quality deterioration during transportation, storage and marketing. The occurrence of physiological disorders such as husk scald, splitting and chilling injury is another challenge reducing marketability and consumer acceptance. Recently, notable work on postharvest biology and technology has been done. Pomegranate is highly sensitive to low-oxygen (<5 kPa) atmospheres, chilling injury and decay. One of the major problems associated with pomegranate fruit is excessive weight loss, which may result in hardening of the husk and browning of the rind and arils. To reduce chilling injury incidence and to extend storability and marketing of pomegranates, good results were obtained with polyamine, heat, salicylic acid, methyl jasmonate or methyl salicylate treatments prior to cold storage. This article reviews the maturity indices, changes during maturation and ripening, postharvest physiology and technology of pomegranate fruit as well as the various postharvest treatments for maintaining fruit quality. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Loquat ( Eriobotrya japonica Lindl.) is a subtropical evergreen tree whose fruit is consumed both fresh and processed. Loquat fruit is a good source of minerals and carotenoids, while the kernel is rich in protein and carbohydrates. It has been considered a non-climacteric fruit, but there is evidence that some cultivars have a ripening pattern similar to that of climacteric fruits. The fruit has a short postharvest life at ambient temperatures and is susceptible to physical and mechanical damage, loss of moisture and nutrients, and decay. Low-temperature storage extends the shelf life of loquat fruit, but some cultivars are severely affected by chilling injury and flesh browning during cold storage. Purple spot, browning and leatheriness are major postharvest disorders. The shelf life of loquat can be extended by modified or controlled atmosphere storage as well as by postharvest treatment with 1-methyl cyclopropene or methyl jasmonate. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Background The effect of storage temperature on physiological responses in Indian jujube ( Ziziphus mauritiana Lamk. cv. Gola) fruit was investigated. Freshly harvested fruits at physiological maturity characterised by colour-turning stage were stored at ambient temperature, 12 and 6 °C for 21, 35 and 35 days respectively. Headspace O2, CO2 and C2H4, moisture content, respiration, ethylene production, firmness, tristimulus colour, chroma, hue angle and chilling injury index were monitored during fruit storage. RESULTS Rates of respiration and ethylene production increased after 1 week of storage at ambient temperature, while peaks were observed after 2 weeks at 12 and 6 °C. Headspace O2 decreased continuously during storage, while CO2 and C2H4 increased at all storage temperatures. Moisture content and firmness also decreased during storage. Hunter L* values increased during storage, which correlated with the darkening of fruit colour. Fruit stored at ambient temperature did not show any chilling injury symptoms, while chilling injury appeared on day 28 under 12 °C storage and on day 21 under 6 °C storage. CONCLUSION Indian jujube fruit showed high rates of respiration and ethylene production that were significantly affected by different storage temperatures. Lower temperatures increased the shelf life of the fruit, but chilling injury was a problem under 6 °C storage. Indian jujube fruit could be stored at 6 °C for up to 35 days if chilling injury could be alleviated. © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]