The effects of red and blue light-emitting diode (LED) lights on the senescence of broccoli (Brassica oleracea L. var. italica) after harvest were investigated. The results showed that irradiation with red LED light was effective in delaying senescence in broccoli after harvest. Under red LED light, the yellowing process was delayed, and ethylene production and reduction of ascorbate (AsA) were suppressed in broccoli after harvest. In contrast, the blue LED light treatment did not significantly affect the senescence process of broccoli after harvest. As the red light is inconvenient for customers in selecting broccoli in the supermarket, we designed a type of modified white LED light. In this modified white LED light, the ratio of blue light was decreased, while the ratio of red light was increased. Under the modified white LED light, AsA reduction in broccoli was slightly delayed on the first and second days after harvest. Moreover, the modulation of AsA reduction by the modified white LED light treatment was highly regulated at the transcriptional level. The up-regulation of the AsA biosynthetic genes (BO-VTC2 and BO-GLDH) and AsA regeneration genes (BO-MDAR1 and BO-MDAR2) contributed to the higher AsA content in the modified white LED light treatment on the first and second days after harvest. The results presented might provide new strategies to improve the nutritional quality of broccoli after harvest.

Cassava is one of the many crops developed in the Gunung Kidul to be used as food. There are many of varieties planted and characteristic are unknown of various cassava varieties, requires the need for research on the characteristics of nutrient content and physical properties, especially for Mocaf production. This research was arranged in a Completely Randomized Design (CRD) with single factor and consisting of 5 treatments, Kirik, Gambyong, Jawa, Gatotkaca, and Bamban varieties. Every treatment was repeated 3 times and every varieties was 9 months of harverst age. Observed variables include moisture content, protein, ash, starch, fiber, fat, carbohydrate, HCN, white color, organoleptic, and viscosity. The result showed that kind varieties of fresh cassava possess nutrient content and different physical properties. Bamban variety is the best quality for making Mocaf which is has the white color (91,53), HCN content of 18,10 ppm, starch content of 77,84 %, protein content of 1,11 %, and dietary fiber content of 9,04 %, but not yet meet the standards of SNI on HCN variables and the amount of starch.

Ascorbate is one of the most abundant soluble antioxidants in the plant. Multiple functions of ascorbate in photo protection have been proposed, including scavenging of reactive oxygen species generated by oxygen photoreduction and photorespiration. There is still unclear information relation to LED light with Ascorbate biosynthesis and metabolism, yellowing, chlorophyll content, and ethylene production in broccoli florets. The effect of light-emitting diodes (LED) light on ascorbate (AsA) biosynthesis and metabolism in broccoli (Brassica oleracea L. var. Italica) cultivar “Ryokurei” were studied using red (660 nm), blue (470 nm) and white LED lights as the light source and also no light treatment as the control. Gene expression involved in the biosynthesis and metabolism of AsA, AsA content, color, chlorophyll content and ethylene production rate on the postharvest broccoli were observed in 4 days. The result showed that after two days, red light treatment significantly (p < 0,05) delayed the decrease of ascorbate content. The result was supported by observations using Real-Time Quantitative RT-PCR showed that red light treatment can suppress mRNA level of BO-APX1, BO-APX2, and BO-sAPX on the third day. Observation of BO-GLDH mRNA level was increased in the third-day exposure of red LED light. Therefore red LED light showed up-regulated AsA biosynthesis transcriptional level. Enzymes which possibility responsible for AsA metabolism and biosynthesis in a row were Ascorbate Peroxide (APX) and L-Galactono-1,4-Lactone Dehydrogenase (GLDH). The regulation of this gene expression might contribute to the suppression of AsA reduction by red LED light treatment in broccoli. Red LED also showed suppression of yellowing and decline the chlorophyll content in postharvest broccoli florets. Keywords: ascorbate, LED; broccoli; gene expression; real-time quantitative RT-PCR.

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Cutting treatment on fresh-cut apple could lead to browning incident in fruit. Several chemicals could be used as an antibrowning agent. In this study, we compared several antibrowning agents in fresh-cut Apple cv Manalagi. This study was carried out in a single factor experimental design and arranged in completely randomized design (CRD) consisting of four treatments: 100 mmol L-Arginine, 150 ppm Citric Acid, 150 ppm Ascorbic Acid, 50 ppm Natrium metabisulfite, and control with no treatment. The result showed that Sodium metabisulfite and L-Arginine treatment significantly could inhibit browning in fresh-cut Apple cv Manalagi on day 10. L-arginine also showed a high overall score in panelist preferences in sensory test. Further study could explore on L-arginine potential as antibrowning agent for other fresh-cut fruit and vegetables.