不同花期石斛花主要营养成分分析与品质比较

为了确定铁皮石斛(Dendrobium officinale)、杂交石斛(Dendrobium officinale×Dendrobium nobile)、球花石斛(Dendrobium thyrsiflorum)及鼓槌石斛(Dendrobium chrysotoxum)花的最佳采收期,测量3个不同花期(花苞期、微花期、盛花期)的多糖、总黄酮和水溶性浸出物含量,并进一步测定最佳采收期的石斛花中氨基酸及矿物质元素含量等营养成分。结果表明:盛花期的铁皮石斛、杂交石斛、球花石斛及微花期的鼓槌石斛花的多糖、总黄酮和水溶性浸出物含量总体上较其他2个时期高;铁皮石斛盛花、杂交石斛盛花、球花石斛盛花、鼓槌石斛微花中必需氨基酸种类齐全,药效氨基酸占总氨基酸的比例为63.8%~66.7%,氨基酸比值系数分(SRC)分别为66.4、65.9、63.1、66.0,第一限制氨基酸均为蛋氨酸+半胱氨酸;4种石斛花中K含量最高(≥2.52×10~6 mg/kg),铁皮石斛盛花中Fe(177.33 mg/kg)、鼓槌石斛微花中Cu(107.00 mg/kg)含量较高。这表明石斛花具有较高的营养价值,为石斛花资源的开发提供了一定的理论依据。

Comparative Analysis of Quality Properties and Main Nutrients in Dendrobium Flowers During Different Flowering Phases

To determine the best harvest time of the flower in Dendrobium offtcinale,D.offwinale × D.nobile,D.thyrsiflorum and D.chrysotoxum,the contents of polysaccharides,total flavonoids and aqueous extract in three stages (budding stage,petals spreading stage and petals opening stage) were analyzed,and then the amino acids and mineral elements in the flower of the best harvest time were measured.The results showed that the contents of polysaccharides,total flavonoids and aqueous extract in the petals opening stage of D.offwinde,D.offtcinale × D.nobile,D.thyrsiflorum and in the petals spreading stage of D.chrysotoxum were,on the whole,higher than the others.Among the total amino acids of the flowers,the medicinal amino acids accounted for 63.8％ to 66.7％,including seven kinds of essential amino acids.The score of ratio coefficient were 66.4,65.9,63.1 and 66.0 in the four Dendrobium flowers,respectively.Methionine and cysteine were the first limiting amino acids.K content was the highest among the four Dendrobium flowers.Fe (177.33 mg/kg) and Cu (107.00mg/kg) were significantly higher in the petals opening stage of D.officinale flower and in the petals spreading stage of D.chrysotoxum flower,respectively.Based on the results,it was concluded that the flower of Dendrobium had higher trophic value.These results showed a certain theoretical basis for the development of Dendrobium flower.