ABSTRACT
Objective: To establish a method for the determination of three main volatile components (menthone, menthol, and pulegone) in Yinqiao Powder (YQP) distillate and provide the evidence for elucidating the scientific connotation of its traditional decocting method "taking when the fragrance volatilized fiercely". Methods: YQP distillates with different decocting time were prepared to study the dynamic changes of chemical components during decocting process. GC-MS was used to analyze the volatile components qualitatively and determine the contents of menthone, menthol, and pulegone in YQP distillate. Results: GC-MS total ion chromatograms of YQP volatile oil included 26 peaks, of which the relative contents of 14 peaks were greater than 1.5%, mainly from Forsythiae Fructus, Menthae Haplocalycis Herba, and Schizonepetae Herba. With the extension of the boiling time, the evaporation rates of menthone, menthol, and pulegone all increased to maximum and then decreased gradually. When boiling for 5-10 min, the maximum average evaporation rates of menthone, menthol, and pulegone were 13.77, 147.74, and 31.26 ìg/min, respectively. When boiling for 0-5, 5-10, 10-15, 15-20, 20-25, 25-30, 30-40, 40-50, 50-60, 60-80, 80-100, and 100-120 min, the average evaporation rates of total three volatile components were 160.23, 192.77, 120.71, 70.85, 54.01, 42.41, 30.36, 17.87, 14.98, 10.01, 7.79, and 7.58 ìg/min, respectively. Conclusion: The evaporation rates of menthone, menthol, and pulegone in YQP are heavily influenced by decocting time. The fragrance is volatilized fiercely at about 5 min after boiling, while the average evaporation rates of menthone, menthol, and pulegone are high, so after boiling for 5-10 min, menthone, menthol, and pulegone were evaporated a lot. The fragrance gets weak after 15 min of boiling, the average evaporation rates of menthone, menthol, and pulegone are decreasing heavily. It is suggested that the traditional decocting method has some scientific foundation.
ABSTRACT
To establish a method for the determination of chemical specific chromatograms and five components in Yinqiao powder decoction, and provide basis for elucidating the scientific connotation of ″taking in when the fragrance volatilized fiercely″. Yinqiao powder decoctions with different decocting times were prepared to study the changes of chemical components during decocting process. Specific chromatograms and contents of chlorogenic acid, phillyrin, arctiin, liquiritin and glycyrrhizin were determined by high performance liquid chromatography. According to the results, the similarities of Yinqiao powder decoctions with different decocting times were high, which indicated that their chemical compositions were similar. The dissolutions of the five components in Yinqiao powder reached more than 39.7% of 2 hour maximum dissolution amounts (MDA) after 20 minutes of soaking, more than 69.5% of MDA when boiling, more than 79.1% of MDA at the 5th minute after boiling, and more than 85.7% of MDA at the 10th minute after boiling. The concentrations of five components were not increasing obviously after 15 minutes of boiling (RSD<4.3%). The fragrance volatilized fiercely at about the 5th minute after boiling, which indicated that the contents of volatile components in Yinqiao powder decoctions were high, but it became weak after boiling for 15 minutes, which indicated that the contents of volatile components in Yinqiao powder decoctions were low. The results showed that the contents of five components in Yinqiao powder decoctions were heavily influenced by the decocting time. When boiling for about 5 minutes, the fragrance volatilized fiercely, both the contents of volatile components and non-volatile components were high. It is suggested that the traditional decocting method has a certain scientific basis.
ABSTRACT
To establish a method for the determination of three volatile components: menthone, menthol and pulegone in Yinqiao powder (YQP) decoction, explore the change rules of volatile components in decocting process, and provide evidence for elucidating the scientific connotation of its traditional decocting method "taking when the fragrance is volatilized fiercely". YQP decoctions with different decocting time were prepared, and GC-MS was used to qualitatively analyze the volatile components and determine the contents of menthone, menthol and pulegone in decoctions. Then the effects of different decocting time on contents of volatile components were investigated. The results showed that the volatile components in YQP decoctions mainly come from Menthae Haplocalycis Herba, Schizonepetae Herba and Forsythiae Fructus. With the extension of decocting time, the concentrations of all the above 3 volatile components in Yinqiao powder decoction were first increased and then decreased. When soaking for 30 minutes, as well as boiling for 0, 5, 10, 15, 20, 30, 40, 50, 60 minutes, the concentrations of menthone in YQP decoction were 0.058, 0.268, 0.216, 0.073, 0.065, 0.048, 0.048, 0.041, 0.038, 0.034 mg•L ⁻¹; the concentrations of menthol were 0.965, 2.847, 3.633, 2.420, 1.539, 1.189, 1.273, 1.188, 0.905, 0.663 mg•L ⁻¹; the concentrations of pulegone were 0.355, 0.522, 0.598, 0.477, 0.374, 0.374, 0.339, 0.355, 0.248, 0.251 mg•L ⁻¹; and the total concentrations were 1.377, 3.637, 4.446, 2.970, 1.979, 1.611, 1.660, 1.583, 1.191, 0.947 mg•L ⁻¹, respectively. The results showed that the contents of menthone, menthol and pulegone in YQP decoctions were heavily influenced by the decocting time. The fragrance was volatilized fiercely at about 5 minutes after boiling, with larger concentrations of the above three volatile components in decoction; the fragrance got weak after 15 minutes of boiling, the concentrations of menthone, menthol and pulegone in YQP decoctions were significantly decreased, indicating that the traditional decocting method "taking when the fragrance is volatilized fiercely" has some scientific foundation.