关键词: 竹叶, 挥发油, 化学成分, 抗氧化活性

Abstract:

The antioxidant capacity of essential oils obtained by steam distillation from four bamboo species of the Bambusa vulgaris, Bambusa multiplex, Phyllostachys pubescens, and Dendrocalamus latiflorus, were evaluated using the DPPH assays. The yield of oils from the leaves of the four species was variable with the greater amount obtained from Bambusa vulgaris（0.827%）, and the least from Phyllostachys pubescens（0.391%）. The chemical compositions in bamboo leaves were analyzed by GC-MS. The results showed that 168 chromatographic humps were gained. 132 kinds of composition were identified. The major volatile components detected and identified by GC-MS were also variable. A major volatile was 3-methyl-2-butanol, detected in four bamboo species（maximum in Dendrocalamus latiflorus at 46.25%）.Other major components detected were 2-methoxy-4-vinylphenol, 2-hexenal, 3,7,11-trimethyl-1,6,10-dodecatrien-3-ol, phytol, benzeneacetaldehyde, nonanal, 6,10,14-trimethyl-2-pentadecanone, 5,6,7,7a-tetrahydro-4,4,7a-trimethyl-2（4H） benzofuranone and isophytol. In the DPPH assays, strong antioxidant capacity was evident in all the oils but the greater antioxidant capacity was shown by that obtained from Bambusa vulgaris （IC₅₀=2.705 mg·mL^-1） compared to Bambusa multiplex（IC₅₀=3.442 mg·mL^-1）. Antioxidant capacity was positively correlated （r=0.91） with the concentration of essential oils. The data indicated that essential oils obtained from various bamboo leaves may play an important role in functional foods and in the preservation of pharmacologic products.

Key words: bamboo leaves, essential oil, chemical compositions, antioxidant activity