甘蔗茎叶的化学成分及抗氧化活性研究

Chemical constituents and antioxidant activities from the stems and leaves of Saccharum officinarum

关键词:  化学成分, 甘蔗, 茎叶, 抗氧化, 活性

Key words:  chemical constituents, Saccharum officinarum, stems and leaves, antioxidant, activity

摘要:

为研究甘蔗(Saccharum officinarum)茎叶的化学成分及抗氧化活性,该文对甘蔗茎叶以甲醇提取,提取物采用柱色谱(SiO₂、Sephadex LH-20、Rp-18)进行分离纯化,根据质谱和核磁共振技术鉴定所得化合物的结构,并通过DPPH法测定化合物的清除自由基能力。结果表明:(1)从甘蔗茎叶部位共分离鉴定22个化合物,分别为对羟基苯甲醛(1)、对甲氧基桂皮酸(2)、4-甲氧基苯甲醛(3)、香草醛(4)、4-羟基肉桂酸甲酯(5)、对羟基苯甲酸(6)、(2-羟基苯基)(苯基)甲酮(7)、对甲基苯甲酸(8)、咖啡酸甲酯(9)、乌头酸A(10)、乌头酸E(11)、5-O-二甲氧基肉桂酰基奎尼酸(12)、槲皮素(13)、槲皮素-3-O-α-L-阿拉伯糖苷(14)、槲皮素-3-O-β-D-吡喃半乳糖苷(15)、硫代二丙酸双十八烷基酯(16)、α-conidendrin(17)、rel-(2α,3β)-7-O-methylcedrusin(18)、3-O-阿魏酰奎宁酸甲酯(19)、木犀草素(20)、(5S,6S)-5,6-dihydro-3,8,10-trihydroxy-5-(4-hydroxy-3-methoxyphenyl)-6-hydroxymethyl-2, 4-dimethoxy-7H-benzo [c]xanthen-7-one)(21)和5-O-阿魏酰奎宁酸甲酯(22),其中化合物2-3、7-11、14-19、21-22为首次从该植物中分离得到。(2)通过DPPH法对含量大的15个化合物(1-9、11-16)进行自由基清除能力的筛选,其中化合物12(5-O-二甲氧基肉桂酰基奎尼酸)显示了较好的抗氧化活性(IC₅₀值为 49.58 μg·mL^-1)。该研究结果丰富了甘蔗抗氧化活性物质基础,为其进一步开发利用提供了科学依据。

Abstract:

To study the chemical constituents and antioxidant activities from the stems and leaves of Saccharum officinarum. Twenty-two compounds were isolated and purified from the MeOH part of the stems and leaves of S. officinarum by means of various column chromatographic techniques, including SiO₂, Sephadex LH-20 and Rp-18 silica gel. Their structures were identified by mass spectrometry and nuclear magnetic resonance; The DPPH method was used to determine the free radical scavenging abilities of the components from S. officinarum. The results were as follows:(1)The compounds were identified as p-hydroxybenzaldehyde(1), p-methoxy-cinnamic acid(2), 4-methoxybenzaldehyde(3), vanillin(4), 4-hydroxy-cinnamic acid methylester(5), p-hydroxybenzoic acid(6),(2-Hydroxyphenyl)(phenyl)methanone(7), p-methylbenzoic acid(8), caffeic acid methyl ester(9), aconitate A(10), aconitate E(11), 5-O-dimethoxycinnamoylquinic acid(12), quercetin(13),quercetin-3-O-α-L-arabinoside(14), quercetin-3-O-β-D-galactopyranoside(15), didodecyl thiodipropionate(propionic acid, 3,3-sulfinyl di-1,1'-didodecyl ester)(16), α-conidendrin(17), rel-(2α,3β)-7-O-methylcedrusin(18), 3-O-Ferulylquinic acid methyl ester(19), luteolin(20),(5S,6S)-5,6-dihydro-3,8,10-trihydroxy-5-(4-hydroxy-3-methoxyphenyl)-6-hydroxymethyl-2,4-dimethoxy-7H-benzo [c]xanthen-7-one)(21), 5-O-Ferulylquinic acid methyl ester(22). Compounds 2-3, 7-11, 14-19, 21-22 were isolated from this plant for the first time.(2)Determination of free radical scavenging abilities of 15 compounds(1-9, 11-16)were selected by DPPH method. Compound 12(5-O-dimethoxycinnamoylquinic acid)had great antioxidant activity(IC₅₀ value was 49.58 μg·mL^-1). This study enrich the material basis of antioxidant activity of S. officinarum, which provides a scientific basis for the further development of S. officinarum.