Antioxidant Systems in Ripening Tomato Fruits

Abstract

Two cultivars of tomato (Lycopersicon esculentum Mill.), Selection-7 (shelf life 7-8 d) and ARTH-3 (shelf life 14-15 d) were analyzed for oxidative stress and the antioxidant enzyme system at different stages of fruit ripening. The results presented here suggest that during the early stages of fruit ripening, efficient antioxidant system protects the tomato fruits against the damaging effect of progressive oxidative stress. At later stages, however, oxidative damage occurs due to decreased activities of the ROS scavenging enzymes.

Oxidative stress and antioxidant systems in Guava (Psidium guajava L.) fruits during ripening

“…These observations are in agreement with those reported earlier in tomato fruits (Ahn et al, 2002;Thakur and Pandey, 1999). However, contrary to this, Mondal et al (2004) and Reddy and Srivastava (2003) found highest SOD activity during MG stage in tomato and mango, respectively. SOD has been reported to decrease during senescence in many plant systems resulting in an increased accumulation of O •-2 radicals and thus oxidative stress (Dhindsa et al, 1981).…”

“…In contrast to SOD (H 2 O 2 producing enzyme), catalase (H 2 O 2 degrading enzyme) activity throughout was higher in L-49 as compared to (Masia, 1998). However, catalase activity increased continuously during ripening of tomato (Andrews et al, 2004;Mondal et al, 2004) fruit, whereas, in saskatoon (Rogiers et al 1998) and orange (Huang et al, 2007), it has been reported to decrease continuously.…”

“…3 Hisar Safeda suggest that membrane deterioration and hence loss of membrane integrity and tissue structure is much faster in soft variety than in the firm one. Membrane deterioration due to increased LOX activity has been reported to be responsible for loss of tissue structure in saskatoon, avocado, pear and tomato fruit during ripening (Kausch and Handa, 1997;Rogiers et al, 1998;Mondal et al, 2004;Liu et al, 2008). Lurie and Ben Arie (1983) demonstrated increased lipid peroxidation in ripening apple and attributed this to increase in LOX activity.…”

“…Therefore, mechanism of membrane deterioration and loss of tissue structure during ripening may also probably be similar to that characterized in true senescing systems involving the accumulation of ROS. Fruits like saskatoon (Rogiers et al, 1998), tomato (Mondal et al, 2004) and orange (Huang et al, 2007) fruits have been reported to accumulate ROS during ripening. Guava (Psidium guajava) is a crop of economic importance and is considered to be a poor man's fruit in India.…”

Partial purification of superoxide dismutase and peroxidase from ber (Zizyphus mauritiana Lamk.) fruit using anion exchange chromatography

“…Though ber tree is hardy and native to hot and arid climate, fruit is highly perishable and undergoes cell wall degradation and fruit softening during ripening and storage (Kohar, 2003). In our laboratory, investigations have been carried out on these aspects in tomato (Mondal et al, 2003(Mondal et al, , 2004. In continuation of these studies, attempts were made to purify SOD from ber fruits.…”