Ensuring high-quality agricultural products has become important in agriculture since society’s standard of living has risen. Meanwhile, Moringa oleifera L. leaf extract (MLE) has been used as a plant biostimulant to improve product quality. The effectiveness of MLE is associated with its beneficial components, consisting of nutrients, phytohormones, secondary metabolites, amino acids, and bioactive compounds. Previous studies have been carried out to find the effects of MLE application on the quality of different crops, including basil, kale, spinach, maize, radish, brinjal, pepper, tomato, grape, strawberry, and more. The results are generally positive concerning physical, nutritional, and chemical qualities. This review comprises recent findings regarding MLE application as a plant biostimulant to increase quality attributes, with its underlying mechanism.

‘Lady Finger’ banana is one of the most-produced bananas in Indonesia. Unfortunately, it has a short fruit shelf life, which became a major problem in post-harvest handling. Shelf life in climacteric fruits can be improved through the inhibition of physiological processes such as ethylene production, respiration, and transpiration by the application of 1-Methylcyclopropene (1-MCP) and chitosan. Physiological process inhibition will influence fruit color, firmness, sugar content, and other postharvest qualities. The potential use of 1-MCP, chitosan, and a combination of both toward postharvest life quality of ‘Lady Finger’ banana were assessed in this study. Four concentrations of 1-MCP (0.25, 0.50, 0.75, and 1.00 µL/L) and also its combination with 1.25% chitosan were applied to the ‘Lady Finger’ banana. The result showed that the combination of 1-MCP and chitosan improved the postharvest life quality of the ‘Lady Finger’ banana. The combination of 1-MCP (0.5–1.0 µL/L) and chitosan increased fruit shelf life up to 5–6 days longer compared to control and inhibited the change of fruit pH, TA, TSS, total sugar, color index, and weight loss. These results indicate that the effect of 1-MCP will be more effective in improving the fruit shelf life of bananas if it is combined with chitosan.

The presence of ethylene during postharvest handling of tomatoes can be the main problem in maintaining fruit shelf-life by accelerating the ripening process and causing several quality changes in fruit. Several researchers have studied the methods for improving the postharvest life of tomato fruit by controlling ethylene response, such as by mutation. New ethylene receptor mutants have been identified, namely Sletr1-1, Sletr1-2, Nr (Never ripe), Sletr4-1, and Sletr5-1. This review identifies the favorable and undesirable effects of several ethylene receptor mutants. Also, the impact of those mutations on the metabolite alteration of tomatoes and the future perspectives of those ethylene receptor mutants. The review data is taken from the primary data of our experiment related to ethylene receptor mutants and the secondary data from numerous publications in Google Scholar and other sources pertaining to ethylene physiology. This review concluded that mutation in the SlETR1 gene was more effective than mutation in NR, SLETR4, and SLETR5 genes in generating a new ethylene mutant. Sletr1-2 mutant is a potential ethylene receptor mutant for developing new tomato cultivars with prolonged fruit-shelf life without any undesirable effect. Therefore, that has many challenges to using the Sletr1-2 mutant for future purposes in breeding programs.

Strawberry (Fragraria x ananassa Duch) cv. Tochiotome is nutrient rich. However, it has a short shelf life, especially at room temperature. Coating is one of the methods used to prolong fruit shelf life. Coating materials, such as nano chitosan (NC) and Aloe vera (AV) gel, are edible and safe to consume. The objective was to analyze the interaction between AV gel and NC concentrations and determine the optimal concentration to improve the quality of strawberries at room temperature. This experiment used a factorial randomized block design with treatments of NC (0, 0.5, and 1%) and AV gel (0, 25, and 50%). The results showed an interaction between AV gel and NC concentrations for all variables. The optimum concentrations to improve the fruit quality of strawberries cv. Tochiotome were 25% AV gel with 1% NC, which increased the value by more than twofold compared with the control (no AV gel and NC) until four days after storage. The fruit quality characteristics were fruit hardness (6.57 N), weight loss (1.23%), titratable acidity (0.74 mL), total phenolic (1.79 µg GAE/FW), total flavonoid (29.85 mg QE/g), vitamin C concentration (43.83 mg/100 g), and shelf life (4.66 days). More than 1% NC may enhance quality. In conclusion, AV and NC are a potential treatment for improving the postharvest quality of strawberry.