Journal of Horticulture and Postharvest Research

Abstract Purpose: The application of natural organic compounds without harmful environmental effects in the production of horticultural and agricultural products is considered as a new method to reduce waste before and after harvesting, increase the storage life and maintain antioxidant activity in developed agriculture. As regards, this study investigated the impact of foliar applications of brown macroalga extract on antioxidant enzyme activity and mineral uptake in 'Hayward' kiwifruits. Research method: Four treatment levels of brown macroalga extract (0, 1, 2, and 3 g/L) were applied at three distinct phases, occurring 110, 125, and 140 days after full bloom. Fruit samples were stored at 1±0.5°C with 95% relative humidity for 90 days, with measurements taken every 30 days. Findings: Results revealed that the 3 g/L extract treatment significantly increased the uptake of calcium (47.82 %), nitrogen (20.52 %), potassium (12.06 %), phosphorus (19.81 %), and iron (25.77 %) compared to the control. The extract demonstrated a substantial effect on all recorded traits. Among the applied treatments, 3 g/L of brown macroalga extract concentration had the best effect in reducing electrolyte leakage (25.10%), malondialdehyde accumulation (96.73%), hydrogen peroxide content (54.54%) and increasing activities of antioxidant enzymes including superoxide dismutase (50.42%), catalase (84.90%), ascorbate peroxidase (79.02%), and peroxidase (49.40%) compared to the control in 90 days of storage. Research limitations: No limitations were found. Originality/Value: The results suggest that the 3 g/L brown macroalga extract concentration holds promise for enhancing the quality of 'Hayward' kiwifruits.

Abstract Purpose: The aim of the study was to identify the impacts of storage temperature on strawberries coated with 3% calcium chloride (CaCl₂) and 0.2% nano-chitosan. Research method: Fresh strawberry fruit were immersed in CaCl₂ solution of 3% for 1 min and drained at room temperature before coating with nano chitosan solution of 0.2 %. The treated fruit was then stored at 0 ^oC, 2 ^oC, 4 ^oC and 25 °C. Physico-chemical analysis was performed in each three-day interval. Findings: Of the four examined temperatures tested, storing the fruit at 0 ^oC was the most effective in maintaining the overall quality index of strawberries up to 21 days. The treatment also reduced weight loss, preserved ascorbic acid content, antioxidant capacity, and total anthocyanin content, prevented microbial growth and prolonged storage-life of treated strawberries up to 21 days. Limitations: the industrial packaging that could affect the actual influences of the studied temperatures was not investigated in this work. Originality/Value: storing fresh strawberries coated with CaCl₂ 3%, nano-chitosan 0.2% at 0 ^oC was the most effective treatment in lengthening the shelf life of the fruit up to 21 days. The combination treatment of coating and storing at 2 ^oC extents strawberry storage life by 6 days when compared to uncoated fruit.

Abstract Purpose: Recently, there are researches showed positive effects of nano-chitosan in prolonging the postharvest quality and shelf life of strawberry, however, influences of storage temperatures on the nano-chitosan coated fruit have been overlooked. Therefore, in this work, changes of physiological traits of strawberry (Fragaria × ananassa Duch.) coated with 0.2% nano-chitosan and stored at different temperatures were studied. Research Method: Strawberry was coated with 0.2% nano-chitosan and stored at different temperatures (2°C, 5°C, 10°C and 25°C) for 12 days. The effects of temperatures on the coated fruits were tested by measuring visual quality, weight loss, antioxidant properties, malondialdehyde content, firmness, total soluble solid, polyphenol oxidase activity in three days intervals. Findings: After storing 0.2% nano-chitosan coated strawberry at four different temperatures, 2°C showed the most effective one as maintaining the overall quality of strawberry higher than the acceptable/marketable level after 12 days; meanwhile, fruits stored at 25°C were quickly decayed after 3 days. The treatments at low temperatures (2°C, and 5°C) significantly reduced weight loss, maintained firmness, total soluble solid, polyphenol oxidase activity and malondialdehyde content of the stored fruits. Limitations: Nano-chitosan has not been widely traded. Originality/Value: Coating strawberry with nano-chitosan and storing at 2°C effectively maintained the postharvest quality of strawberry as well. This treatment is quite simple and would be useful for stakeholders in the strawberry supply chain.