Ripening of pepper (Capsicum annuum L.) fruits is characterized a shift in the fruit color from green to red, yellow, orange or purple depending on the variety. This event implies chlorophyll breakdown and synthesis of new carotenoids and anthocyanins, emission of organic volatiles, new protein synthesis and cleavage of existing ones and cell wall softening, among others [1]. From a metabolic point of view, this physiological process is accompanied by an increase of the lipid peroxidation, the activity of some enzymes such the superoxide-generating respiratory burst oxidative homolog (Rboh) and NADP-dehydrogenases, as well as by higher NADPH levels and some post-translational modification of proteins. Conversely, during ripening nitric oxide (NO) content and catalase activity lower [2]. NO has been proved to delay pepper fruit ripening and to enhance about 40% the ascorbate concentration [3,4]. Recent research carried out in our laboratory found that garlic (Allium sativum L.) clove samples release considerable amounts of NO. In this work, incubation of pepper fruits in the presence of garlic preparations was achieved. Then, diverse biochemical, nutritional and commercial parameters such as ascorbate, glutathione, carotenoids and flavonoids, among others, were determined in treated pepper fruits. Our data indicate that garlic preparations exerted similar effects as NO in pepper fruits, delaying ripening and increasing some trait values such as ascorbate, glutathione and flavonoids. These results suggest that this experimental design could be up-scaled for agro-biotechnological purposes with the circular economy being promoted.

[1] Palma et al., 2020, Antioxidants 9, 878.

[2] Chu-Puga et al., 2019, Antioxidants 8, 9.

[3] Chaki et al., 2015, Ann. Bot. 116: 637-647.

[4] Rodríguez-Ruiz et al., 2017, Redox Biol. 12, 171-181.

[Supported by grants PID2019-103924GB-I00 and P18-FR-1359 from MICINN and PAIDI-Junta de Andalucía, Spain]