Changes of Antioxidant Enzyme and Phenylalanine Ammonia-Lyase Activities during Chimonanthus praecox Seed Maturation

Abstract

Changes in peroxidase (POD), superoxide dismutase (SOD), catalase (CAT) and phenylalanine ammonia-lyase (PAL) activities were studied during Chimonanthus praecox seed maturation. According to our findings the protein content increased steadily from 8 to 12 weeks after flowering, and thereafter decreased significantly. Similarly, SOD and POD activities increased gradually up to 12 weeks after flowering and then declined. PAL activity declined gradually during seed maturation. CAT activity, however, showed no changes during seed maturation. By means of polyacrylamide gel electrophoresis (PAGE), SOD and POD isoenzymes were observed during seed maturation. The staining intensities of SOD and POD isoenzymes correlated well with SOD and POD activities as obtained by an assay in solution. These findings suggest that POD, SOD and PAL may be involved in the growth and development during Chimonanthus praecox seed maturation.

The effect and mechanism of ultrasonic treatment on the postharvest texture of shiitake mushrooms (Lentinula edodes)

“…Catalase is an enzyme used by organisms to degrade H 2 O 2 and resist oxidative stress, SOD is a key fungal enzyme for resistance to oxidative stress, and PAL is important for the lignin metabolic pathway in edible fungi, which directly affects lignin content. It was reported that the accumulation of PAL was important for the defence function (He & Gao, ; Notsu et al ., ). In another report, γ‐irradiation was applied for the preservation of mushrooms, which caused PAL excitation and total phenolic accumulation (Benoît et al ., ).…”

Physiological changes and sHSPs genes relative transcription in relation to the acquisition of seed germination during maturation of hybrid rice seed

“…Similarly, the SOD activities in the wheat embryos had no significant changes in fresh seeds after the end of filling, and remained at a similar value after artificial drying . The SOD activity increased significantly from 8 to 12 weeks after flowering, and then slightly decreased at 15 weeks after flowering . The high activity of SOD suggested that it may play an important role in combating oxidative stress, and obviously no change during the seed development suggested that losing water naturally had little influence on the free radicals removal and production.…”

“…The changes of the POD and CAT activity had no significant correlation with hybrid rice seed maturation and seed vigour. The POD activity increased continuously up to 12 weeks after flowering, while the activity decreased significantly at 15 weeks after flowering during Chimonanthus praecox seed development . The CAT activity increased significantly during seed development and was dependent on seed moisture content in sunflower .…”

“…Reactive oxygen species (ROS) are known to occur during seed development, where they have a dual function being either cytotoxic or playing a role in development, dormancy breakage, and defence against biotic and abiotic stresses . The activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) significantly changed during seed development . The small heat shock proteins (sHSPs) are usually undetectable in vegetative tissues under normal growth conditions, but can be induced by environmental stresses and developmental stimuli.…”

Maturation and Resting of Sweet Pepper Fruits on Physiological Quality and Biochemical Response of Seeds

“…Activity of the POD enzyme increased with fruit age, with maximum values at 80 DAA estimated at 0.32 and 0.22 μmol purpurogaline min -1 mg -1 protein in treatments with and without fruit rest, respectively (Figure 3). Increases in SOD and POD activities, especially in the early stage of seed maturation, indicate increased oxidative stress to regulate ROS level [27], as well as increases in CAT activity represents a greater ability to eliminate H2O2 [1], because it is the main enzyme involved in hydrogen peroxide removal [28]. However, this enzyme is only actived at high concentrations of H2O2 [27], thus, it can be supposed that the enzyme that acted during the seed maturation process from 50 to 80 DAA was possibly POD.…”