Accumulation Characteristics of Total Phenolics, Flavonoids and Polysaccharides in Vegetable Jute Leaves of Different Growth Stages
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摘要:
目的 探究不同生育期菜用黄麻(Corchorus capsularis L.)叶片总酚、总黄酮、多糖等生物活性成分的积累特性,为菜用黄麻的合理采收及开发利用提供参考依据。 方法 以桂麻菜1号和桂麻菜2号为试验材料,以秋葵、山药、油麦菜为对照,分别于苗期、打顶期、开花期、蒴果期测定分析菜用黄麻叶片总酚、总黄酮、多糖含量的积累变化规律,比较菜用黄麻与对照品种的差异,分析生育期与总酚、总黄酮、多糖含量的相关性。 结果 同一品种在不同生育期总酚、总黄酮和多糖含量均存在差异。2个菜用黄麻品种的总酚含量随生育期延长呈现先下降后上升的趋势,蒴果期的含量显著高于(P<0.05,下同)其他生育期,分别达4.064 mg·g−1和3.852 mg·g−1;生育期相同时桂麻菜1号的总酚含量在苗期和蒴果期高于桂麻菜2号。随生育期延长桂麻菜1号的总黄酮含量呈现先上升后下降的趋势,在开花期时含量最高,达2.755 mg·g−1;桂麻菜2号呈现上升的趋势,在蒴果期含量最高,达4.755 mg·g−1,显著高于其他生育期;生育期相同时桂麻菜2号的总黄酮含量均显著高于桂麻菜1号。随生育期的延长桂麻菜1号的多糖含量呈现波动上升的趋势,桂麻菜2号的多糖含量呈现先下降后上升的趋势;2个菜用黄麻品种蒴果期时的多糖含量均显著高于其他生育期,分别达3.175%和1.240%;生育期相同时桂麻菜2号仅在苗期时多糖含量高于桂麻菜1号。2个菜用黄麻品种各生育期的总酚、总黄酮含量均显著高于对照品种,但多糖含量显著低于秋葵和山药,在蒴果期时多糖含量显著高于油麦菜。仅桂麻菜2号的总黄酮含量与生育期呈显著的正相关,其他均不显著相关。 结论 蒴果期采收菜用黄麻叶更有利于总酚、总黄酮、多糖的累积。 Abstract:Objective To study the accumulation characteristics of bioactive components such as total phenolics, flavonoids and polysaccharides in vegetable jute leaves at different growth stages, and to provide a reference for the rational harvesting, development and utilization of vegetable jute. Method Guimacai 1 and Guimacai 2 were used as experimental materials, and okra, Chinese yam and lettuce were used as control. The contents of total phenolics, flavonoids and polysaccharides in leaves of vegetable jutes were measured and analyzed at seedling stage, topping stage, flowering stage and capsule stage. The differences between vegetable jutes and control varieties were compared, and the correlation between growth stage and total phenolics, flavonoids, polysaccharides were analyzed. Result There were differences in the contents of total phenolics, flavonoids and polysaccharides in the same variety at different growth stages . With the extension of growth stage, the total phenolics content of the two vegetable jutes showed a trend of decreased first and then increased, and the total phenolics content in capsule stage was significantly higher than that in other growth stages, reaching 4.064 mg·g−1 and 3.852 mg·g−1, respectively. The total phenolics content of Guimacai 1 was higher than Guimacai 2 at seedling stage and capsule stage. With the extension of growth stage, the total flavonoids content of Guimacai 1 showed a trend of increased first and then decreased, and the highest content reached 2.755mg·g−1 at flowering stage. With the extension of growth stage, the total flavonoids content of Guimacai 2 showed an showed an increasing trend and the highest content in capsule stage was 4.755 mg·g−1, which was significantly higher than that in other growth stages.The total flavonoids content of Guimacai 2 was significantly higher than that of Guimacai 1 at the same growth stage.With the extension of growth stage, the polysaccharide content of Guimacai 1 showed showed a trend of fluctuated upward, the polysaccharide content of Guimacai 2 showed a trend of first decrease and then increase. The polysaccharide content of two vegetable jute varieties in the capsule stage was significantly higher than that in other growth stages, up to 3.175% and 1.240%, respectively. At the same growth stage, the polysaccharide content of Gammacai 2 was higher than that of Gammacai 1 only at the seedling stage. The contents of total phenolics and flavonoids of the two vegetable jute varieties were significantly higher than those of the control varieties at each growth stage, but the polysaccharide content was significantly lower than that of okra and Chinese yam, and the polysaccharide content was significantly higher than that of lettuce at capsule stage. Only the total flavonoid content of Guimacai2 was significantly positively correlated with the growth stage, while the others were not significantly correlated. Conclusion The vegetable jute leaves harvested at capsule stage were more conducive to the accumulation of total phenolics, total flavonoids and polysaccharides. -
Key words:
- vegetable jute /
- total phenolics /
- total flavonoids /
- polysaccharides /
- growth stage
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表 1 不同生育期各品种总酚含量的变化
Table 1. Changes of total phenolics content in different varieties at different growth stages
生育期
Growth stage总酚含量
Total phenolics content/(mg·g−1)桂麻菜1号
Guimacai 1桂麻菜2号
Guimacai 2山药
Chinese yam秋葵
Okra油麦菜
Lettuce苗期
Seedling stage3.631±0.036 Ba 3.614±0.022 Ba 0.710±0.005 Ad 2.625±0.046 Ab 2.453±0.022 Ac 打顶期
Topping stage2.769±0.065 Db 3.101±0.019 Ca 0.710±0.005 Ae 2.625±0.046 Ac 2.453±0.022 Ad 开花期
Flowering stage3.494±0.045 Ca 3.626±0.162 Ba 0.710±0.005 Ad 2.625±0.046 Ab 2.453±0.022 Ac 蒴果期
Capsule stage4.064±0.032 Aa 3.852±0.038 Ab 0.710±0.005 Ae 2.625±0.046 Ac 2.453±0.022 Ad 同一品种同列数据后不同大写字母表示不同生育期间差异显著(P<0.05),同行数据后不同小写字母表示不同品种间差异显著(P<0.05)。下同。
Different capital letters in the same column of the same cultivar indicated significant difference between growth stage (P<0.05). Different lowercase letters in the same row indicated significant difference between different varieties (P<0.05). Same for below.表 2 不同生育期各品种总黄酮含量的变化
Table 2. Changes of total flavonoids content in different varieties at different growth stages
生育期
Growth stage总黄酮含量
Total flavonoids content/(mg·g−1)桂麻菜1号
Guimacai 1桂麻菜2号
Guimacai 2山药
Chinese yam秋葵
Okra油麦菜
Lettuce苗期
Seedling stage1.870±0.040 Cb 2.435±0.065 Da — — 1.245±0.015 Ac 打顶期
Topping stage2.745±0.015 Ab 3.170±0.090 Ca — — 1.245±0.015 Ac 开花期
Flowering stage2.755±0.005 Ab 4.085±0.075 Ba — — 1.245±0.015 Ac 蒴果期
Capsule stage2.485±0.015 Bb 4.755±0.155 Aa — — 1.245±0.015 Ac —表示未检出。
—indicated undetected.表 3 不同育期各品种多糖含量的变化
Table 3. Changes of polysaccharides content in different varieties at different growth stages
生育期
Growth stage多糖含量
Polysaccharides content/ %桂麻菜1号
Guimacai 1桂麻菜2号
Guimacai 2山药
Chinese yam秋葵
Okra油麦菜
Lettuce苗期
Seedling stage0.441±0.017 Cd 0.717±0.020 Bc 6.795±0.085 Ab 8.140±0.300 Aa 0.378±0.010 Ad 打顶期
Topping stage0.737±0.012 Bc 0.271±0.008 Cd 6.795±0.085 Ab 8.140±0.300 Aa 0.378±0.010 Ad 开花期
Flowering stage0.315±0.011 Dc 0.240±0.009 Cc 6.795±0.085 Ab 8.140±0.300 Aa 0.378±0.010 Ac 蒴果期
Capsule stage3.175±0.045 Ac 1.240±0.030 Ad 6.795±0.085 Ab 8.140±0.300 Aa 0.378±0.010 Ae 表 4 生育期与菜用黄麻叶片总酚、总黄酮、多糖含量的相关性分析
Table 4. Correlation analysis between growth stage and contents of total phenolics, total flavonoids and polysaccharides in vegetable jute leaves
品种
Varieties因素
Factors生育期
Growth stage总酚
Total phenolics总黄酮
Total flavonoids多糖
Polysaccharides桂麻菜1号
Guimacai 1生育期 Growth stage 1.000 总酚 Total phenolics 0.576 1.000 总黄酮 Total flavonoids 0.495 −0.410 1.000 多糖 Polysaccharides 0.754 0.622 0.068 1.000 桂麻菜2号
Guimacai 2生育期 Growth stage 1.000 总酚 Total phenolics 0.596 1.000 总黄酮 Total flavonoids 0.995** 0.520 1.000 多糖 Polysaccharides 0.479 0.719 0.397 1.000 **表示在0.01水平上呈极显著相关。
**indicates extremely significant difference at P<0.01. -
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