Biosynthesis of ascorbic acid in germinating rapeseed cultivars

Area of Science:

• Agricultural Science
• Biochemistry
• Plant Physiology

Background:

• Ascorbic acid (vitamin C) is a vital antioxidant and essential nutrient.
• Rapeseed (Brassica napus) is a globally important oilseed crop.
• Understanding vitamin biosynthesis in plants is crucial for nutritional enhancement.

Purpose of the Study:

• To investigate ascorbic acid biosynthesis in germinating rapeseed.
• To evaluate the effects of gamma irradiation and soaking on vitamin C levels.
• To determine the relationship between germination time and ascorbic acid production.

Main Methods:

• Rapeseed cultivars were germinated at ambient temperatures (20-35°C).
• Seeds were subjected to varying doses of gamma irradiation (0.05-0.20 kGy) or soaking.
• Ascorbic acid content was quantified at different germination intervals (up to 96 hours).

Main Results:

• Ascorbic acid content ranged from 19.8-24.1 mg/100 g in seeds.
• Vitamin C synthesis increased significantly (three-fold) with germination time (p < 0.05).
• Maximum ascorbic acid levels were observed at 0.10 kGy (342.1 mg/100 g dry weight) and 0.15 kGy (113.8 mg/100 g wet weight) after 96 hours.
• Soaking seeds for 24 hours led to a decrease in vitamin C content.
• A significant linear correlation (r = 0.96) was found between vitamin biosynthesis and germination time up to 96 hours.

Conclusions:

• Germination time is a key factor influencing ascorbic acid biosynthesis in rapeseed.
• Specific gamma irradiation doses can enhance vitamin C accumulation in germinating rapeseed.
• Soaking negatively impacts ascorbic acid levels during rapeseed germination.