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The potential of salicylic acid (SA) in delaying postharvest fruit senescence has been extensively documented; nevertheless, its effect on antioxidant activity and quality of 'France' prune fruit is largely unknown. The study investigated the effects of SA (0.5 mM) on postharvest quality deterioration of 'France' prune fruit. Results indicated that SA impeded the increase in respiration rate and weight loss, and mitigated the decrease of soluble solids content (SSC), titratable acidity (TA) content, firmness, and hue angle. SA sustained the ascorbate-glutathione cycle by inducing the production of ascorbic acid (AsA) and glutathione (GSH) and attenuates flavonoids, total phenols, and anthocyanins degradation by inhibiting polyphenol oxidase (PPO) activity and PdPPO. Moreover, SA significantly improved superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), peroxidase (POD), and glutathione reductase (GR) activities and gene expression levels, sustained higher 2,2′-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) and 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging capacity, ferric reducing antioxidant power (FRAP), and hydroxyl radical (·OH) inhibition capacity, and impeded the production of hydrogen peroxide (H2O2) and superoxide anion (O2•−). Overall, SA improved the antioxidant capacity by inducing the synthesis of defense response-related substances and promoting antioxidant enzyme activities to sustain the storage quality of 'France' prune fruit. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of 1‐methylcyclopropene (1‐MCP) treatment on the storage quality and volatile compounds of Xiaobai apricot fruit stored at 4°C. Three groups of apricot fruit were set in a 1 m3 container and treated with 0.5, 1, 1.5 μl/L of 1‐MCP for 20 hr at 20°C, respectively. The physiological parameters and volatile compounds of 1‐MCP‐treated and untreated apricot fruit were examined. Twenty‐eight volatile compounds were isolated and identified, and the main aroma compounds were determined to be linalool, α‐terpenol, 6‐methyl‐5‐hepten‐2‐one, theaspirane, benzaldehyde, nonanal, linalyl formate, butyl acetate, and hexyl acetate. The result showed that 1 μl/L of 1‐MCP treatment had the most effective impact on delaying the ethylene production, respiration rates, soluble solids content, and maintaining firmness, titratable acidity, and ascorbic acid content, and 0.5 and 1 μl/L inhibited the production of most volatile compounds during storage. Novelty impact statement: 1‐MCP treatment can keep apricot fruit in good quality, but decreased the production of Volatile compounds.Linalyl formate and the aspirane were isolated and identified, and these were hardly found in apricot fruit in the previous report.A high concentration of 1‐MCP treatment may promote the production of volatile compounds. [ABSTRACT FROM AUTHOR]

Melatonin (MT) treatment has been proven to improve fruit quality. Herein, the efficacy of 0.5 mmol L−1 MT treatment on carbohydrate metabolism, fruit softening, and their relationship during storage of harvested Hami melons was investigated. The results indicated that compared with those in control group, MT treatment markedly delayed fruit softening and the total soluble solids/titratable acid ratio, inhibited cell wall polysaccharide degradation, and maintained the cell wall integrity in Hami melons. Besides, MT treated also increased the starch, sucrose, and sorbitol contents, enhanced sucrose phosphate synthase and sucrose synthase synthesis activities, whereas reduced pectin methyl esterase, polygalacturonase, cellulase, β-galactosidase, β-glucosidase, xyloglucan endotransglycosylase, amylase, sucrose synthase-cleavage, acid invertase, neutral invertase, sorbitol oxidase, NAD-sorbitol dehydrogenase, NADP-sorbitol dehydrogenase activities in Hami melons. Additionally, MT treatment downregulated the expression levels of CmPG , Cmβ-gal , CmAmy , CmAI , CmNI and CmSOX , and upregulated the expression of CmSPS. Collectively, MT could slow fruit softening and prolong its shelf life by regulating carbohydrate metabolism. [Display omitted] • Melatonin maintained high firmness and delayed the senescence of Hami melon fruit. • Melatonin inhibited cell wall polysaccharide degradation and cell plasmolysis. • Melatonin maintained the cell wall integrity and delayed Hami melon fruit softening. • Melatonin treatment alters carbohydrate metabolism of Hami melons. • Carbohydrate metabolism is closely related to fruit softening. [ABSTRACT FROM AUTHOR]

Epicuticular wax is the outermost protective layer of fruit against abiotic stress. It is easily removed or destroyed during the postharvest transportation and handling of fruit. In this study, the effects of wax layer removal on the postharvest quality of Hami melon fruit and its possible mechanism were explored. The results showed that wax removal accelerated fruit softening, water loss, and decay, reduced sensory and nutritional quality, and shortened shelf life. At the end of storage, the antioxidant enzyme activity and non-enzymatic antioxidant content of wax-removed fruit were reduced, while the accumulation of reactive oxygen species and lipid peroxidation were accelerated. Moreover, the organelle membrane structure and plastids were destroyed. Therefore, epicuticular wax layer plays an important role in maintaining postharvest fruit quality. This study will improve our understanding of the biological function of Hami melon fruit epicuticular wax and helpful for developing effective preservation measures to delay fruit decay. • Epicuticular wax layer of Hami melon fruit has an irregular lamellar structure. • Wax layer loss affects the sensory and nutritional quality of Hami melon fruit. • Epicuticular wax removal disrupts reactive oxygen metabolism and membrane structure. [ABSTRACT FROM AUTHOR]

• NFTS had the best effect on storage quality compared to low and room temperatures. • Near-freezing temperature storage (NFTS) delayed senescence in P. domestica fruit. • NFTS reduced ROS accumulation and enhanced antioxidant enzymes activity. • NFTS is effective for maintaining P. domestica fruit quality during storage. P. domestica fruit are highly perishable due to its intense metabolic activity. To increase the storage time while preserving the quality, the effects of postharvest storage at near-freezing temperature (NFTS) (−1 to −1.5 °C) on the physiological indexes and antioxidant enzyme activities of P. domestica fruit were investigated. The results showed that the weight loss rate (4.04 %), soluble solid content (1.08 %), color difference (18.27 %), respiration rate (23.90 %), anthocyanin content (41.13 %), malondialdehyde content (5.39 %), hydrogen peroxide content (13.32 %), and superoxide anion activity (13.97 %) of P. domestica fruit in the NFTS group were reduced, but the firmness (4.95 %), ascorbic acid content (31.71 %), total phenol content (2.54 %), and the activities of superoxide dismutase (SOD, 4.67 %), catalase (CAT, 168.92 %), ascorbate peroxidase (APX, 127.17 %), and peroxidase (POD, 34.54 %) were increased, compared with the room temperature (25 °C) group. Therefore, NFTS could effectively preserve the quality of harvested P. domestica fruit, improve the antioxidant properties, and delay the senescence. This study proposed that NFTS could be used as a promising storage technique to reduce postharvest oxidative stress. [ABSTRACT FROM AUTHOR]

Winter jujube inevitably suffers from rapid oxidation after harvest, leading to quality deterioration. Temperature plays an important role in the ripening and senescence of fruit. This study aimed to investigate the effect of different temperatures on the quality parameters, antioxidant enzyme activities, and antioxidant enzyme-related gene expressions of winter jujube. Jujube fruit were stored at room temperature (RT: 25 °C) and low temperature (LT: 0 °C) for 35 days, respectively. Compared with RT, LT maintained higher firmness and lower respiratory rate, inhibited the increase of weight loss, decay rate, total soluble solids (TSS) and reddening rate, delayed the decrease of titratable acid (TA) and ascorbic acid (AsA) content. LT-stored jujube fruit also showed higher antioxidant enzyme activities and related gene expression (Mn-SOD, APX, and GR , except CAT). We observed a significant correlation between fruit quality parameters and antioxidant enzymes, suggesting that fruit senescence is closely related to antioxidant ability. In short, LT delayed the ripening rate by inducing a series of physiological and molecular reactions, thereby improving antioxidant levels and storage quality. • Jujube ripening and senescence were investigated at room temperature and 0 °C. • Low temperature storage reduced respiration, weight loss, and decay. • Low temperature induced higher antioxidant enzyme activities and gene expressions. • Fruit quality parameters and antioxidant enzymes correlated significantly. • Fruit senescence may be closely related to the plant's antioxidant ability. [ABSTRACT FROM AUTHOR]

• Compound treatment (1-MCP+chitosan) was applied to the storage and preservation of jujube fruit. • The effect of composite treatment is better than that of single treatment of chitosan and 1MCP. • The compound treatment can effectively improve the activity of antioxidant enzymes and delay the senescence of fruit. • Compound treatment has a great contribution to prolong the storage and fresh-keeping period of jujube fruit. The purpose of this study was to investigate the effects of 1-methylcyclopropene (1-MCP) and chitosan treatment on the storage of Xinjiang jujube fruit at 0 ± 1 °C (relative humidity 90 %–95 %) for 42 d. Indicators such as rotting rate, firmness, and soluble solids as well as peroxidase (POD), polyphenol oxidase (PPO), lipoxygenase (LOX), superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) activities were measured. The results showed that 1-MCP or chitosan treatment alone inhibits rotting, delays the decline of soluble solids, maintains fruit firmness, and inhibits the accumulation of malondialdehyde. Furthermore, the activities of antioxidant enzymes such as POD, SOD, CAT, and APX are increased, while those of PPO and LOX are inhibited. However, the effect of 1-MCP and chitosan together is superior to that of 1-MCP or chitosan treatment alone. In conclusion, our results indicate that combined 1-MCP and chitosan treatment is an effective strategy for improving the postharvest quality and prolonging the shelf life of Xinjiang jujube fruit. [ABSTRACT FROM AUTHOR]