international units (IU) per gram dry weight of spawn (1 IU = quantity of enzyme required to produce 1 μmol of glucose per minute under the assay conditions). The isozyme patterns of esterase, peroxidase, and polyphenol oxidase of immobilized spawn and solid
Lanqing Wang, Yinfeng Li, Dehai Liu, Chaohui Zhang, Yuancheng Qi, Yuqian Gao, Jinwen Shen, and Liyou Qiu
Shiow Y. Wang, Kim S. Lewers, Linda Bowman, and Min Ding
main antioxidant enzymes in strawberry fruit are superoxide dismutase (SOD), guaiacol peroxidase (G-POD), glutathione peroxidase (GSH-POD), ascorbate peroxidase (AsA-POD), monodehydroascorbate reductase (MDAR), dehydroascorbate reductase (DHAR), and
Na Zhang, Lu Han, Lixin Xu, and Xunzhong Zhang
). Ascorbate peroxidase is a H 2 O 2 -scavenging enzyme that is unique to plants and is indispensable to protect chloroplasts and other cellular constituents from damage caused by H 2 O 2 and hydroxyl radicals (•HO) produced from it ( Asada, 1992 ). Better
Yali He and Bingru Huang
substrates, and it is therefore likely to be central in the defense mechanism ( Bowler et al., 1992 ). Hydrogen peroxide is scavenged by catalase (CAT) and peroxidases, which convert hydrogen peroxide to water and molecular oxygen ( Bowler et al., 1992
Jing Tian, Li-Ping Wang, Yan-Juan Yang, Jin Sun, and Shi-Rong Guo
reduction of nitroblue tetrazolium (NBT), which was monitored at 560 nm using a spectrophotometer (WFZ ultraviolet/VIS-2600; UNIC, Shanghai, China). Peroxidase (POD) (EC 1.11.1.7) activity was measured according to Kochba et al. (1977) , and one unit of
Xunzhong Zhang, Damai Zhou, Erik H. Ervin, Greg K. Evanylo, Derik Cataldi, and Jinling Li
H 2 O 2 , and 0.1 mL enzyme extract. Ascorbate peroxidase activity. APX activity was assayed by following the decline in absorbance at 290 nm as a result of ascorbate acid oxidation (ɛ = 2.8 m m −1 ·cm −1 ) for 1 min. The reaction mixture contained 0
Ju Ding, Kai Shi, Yan-Hong Zhou, and Jing-Quan Yu
). In cucumber plants, increased activities of peroxidase (POD) and polyphenoloxidase (PPO) enzymes, which are involved in the metabolism of polyphenols, have been suggested as a factor contributing to BR-induced disease resistance ( Khripach et al
Lixin Xu, Mili Zhang, Xunzhong Zhang, and Lie-Bao Han
Bergmeyer (1974) . Leaf sample (200 mg) was homogenized in 3 mL of 100 m m sodium phosphate buffer (pH 6.8) and the extracts were centrifuged at 16,000 g n for 5 min at 4 °C. Then 0.17 mL of supernatant was added to 0.83 mL peroxidase reagent containing
Xinhua Zhang, Fujun Li, Nana Ji, Shujun Shao, Dongyang Wang, Ling Li, and Fansheng Cheng
activity during the entire storage periods ( Fig. 5D ). Fig. 5. Effect of methyl jasmonate (MeJA) treatment on superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD) activities in tomato fruit during storage at 2 °C
Yiwei Jiang, Eric Watkins, Shuwei Liu, Xiaoqing Yu, and Na Luo
different cellular locations ( Alscher et al., 2002 ). The H 2 O 2 can be decomposed through cycles of ascorbate-glutathione, glutathione peroxidase, and catalase (CAT) ( Mittler, 2002 ). The mechanisms of these antioxidative pathways suggest that