採收時期與炮製方法對臺灣白及有效成分品質之評估

Abstract

臺灣白及 (Bletilla formosana (Hayata) Schltr.) 為蘭科多年生草本植物，並為臺灣原生種，其假球莖為傳統中藥白及的理血藥。為了解生長時期與採收季節對臺灣白及產量與成分之影響，本研究以花蓮縣光復鄉栽培的臺灣白及為材料，於冬季採收栽培 1、2、3 年的全株，於夏季採收 1.5、2.5、3.5 年的全株，以假球莖直徑 3 公分為界進行分級，調查農藝性狀與產量構成要素，並且測定假球莖的代謝物含量；同時，為了解臺灣白及炮製處理的理想條件，本研究於夏季採收栽培 3.5 年的假球莖，分別進行 5 種時長的蒸製、煮製處理，分析假球莖的代謝物含量。結果顯示，隨著栽培年分增加，臺灣白及的假球莖總數與總乾重提升，大、小假球莖間的植化素含量差異縮小；採收季節中，冬季採收的假球莖之天麻苷、Militarine 含量顯著高於夏季，顯示冬季為較佳的採收時期；複合產量與品質評估，推斷於冬季採收栽培 3 年的臺灣白及假球莖較佳。另一方面，不同炮製方法與處理時長下，假球莖的代謝物含量皆有顯著差異，當以天麻苷與 Militarine 含量為炮製品質的共同判斷標準時，推斷理想的蒸製處理時長為大假球莖 45 分鐘、小假球莖 30 分鐘；理想的煮製處理時長於大、小假球莖皆為 15 分鐘。本篇研究結果可以做為臺灣白及生產栽培與炮製處理之規劃參考。

Bletilla formosana (Hayata) Schltr. is one of the native species of the Orchidaceae family in Taiwan, of which pseudobulb can be used as traditional Chinese medicine, Bletillae Rhizoma. As a perennial herb, research based on yearly and seasonal changes of the phytochemical content in Bletilla formosana pseudobulbs remains insufficient; additionally, regarding the thermal processing of traditional medicine, there is no detailed method in the literature of Bletillae. In this study, in the aim to determine the effect of harvest time on the yield and the quality of Bletilla formosana, the materials were grown in Guangfu township, Hualien county; plants aged 1, 2, and 3 years were collected in winter, while plants aged 1.5, 2.5, and 3.5 years were collected in summer, then the grading of large and small pseudobulbs was set based on a diameter of 3cm; next, agronomic traits and yield components were measured, and metabolites content was analyzed. Simultaneously, in order to examine the effect of the processing method on the quality of Bletilla formosana, plants aged 3.5 years were collected, and the pseudobulbs were processed through 5 sequential time settings of steaming and boiling treatments, respectively; afterwards, metabolites content was analyzed. The results showed that, as the growing year length extended, the number and the dry weight of pseudobulbs per hill increased, and the gap in phytochemical content between graded pseudobulbs decreased; pseudobulbs harvested in winter contained more gastrodin and militarine content than those in summer; based on the quality and quantity of Bletilla formosana pseudobulbs, the optimal time to harvest is during winter for plants aged 3 years. Meanwhile, significant changes in metabolites content were observed under different processing treatments, and the quality of pseudobulbs was estimated based on the gastrodin and militarine content. The ideal steaming treatment duration for the large pseudobulbs is 45 minutes, for the small is 30 minutes; the ideal boiling treatment duration for both the large and small pseudobulbs is 15 minutes. The findings of this study could assist in scheduling the cropping calendar based on the quality and quantity of Bletilla formosana; on the other hand, this study had shed more light on the quality control of Bletilla formosana pseudobulbs during thermal processing.