Metabolic Accumulation Pattern Of Volatiles In Houttuynia Cordata Thunb.

The effective components of medicinal plants(Including Traditional Chinese Medicine, TCM) are mostly secondary metabolites, but their distribution of the whole plant with the quantity, quality time and space are not evenly and have highly specific of species, organs, tissues and growth stages. Recognizing metabolic accumulation pattern of secondary metabolites and exploring mechanism of the metabolic accumulation will be important significance to reveal stable and controllable quality of medicinal plants(TCM). So this paper is that metabolic accumulation pattern of volatiles in Houttuynia cordata Thunb. is clarified and mechanism of the metabolic accumulation is explored via H. cordata volatiles analyzed by gas chromatoraphy-mass spectrometry(GC-MS).The results obtained were following:1. The validated methods using naphthalene as the internal standard, using GC-MS, developed for simultaneous determination of 24 volatiles was established including α-pinene, camphene, β-pinene, β-myrcene, limonene, cineole, trans-2-hexenal, γ-terpinene, cis-3-hexenyl-acetate, hexanol, α-pinene oxide, cis-3-hexen-1-ol, trans-2-hexen-1-ol, decanal, linalool, bornyl acetate, 2-undecanone, β-caryophyllene, borneol, decanol, 2-tetradecanone, eugenol, iso-phytol, phytol. Analysis condition optimized: Factor FourTM capillary column VF- WAXms(30 m × 0.25 mm × 0.25 μm), Temperature programming, helium as carrier gas(99.999%), EI ion source, Selective ion scan. The method has good linear relationship with the values of r2 situated between 0.9991 ~ 0.9997 and their recoveries varied from 98 ~ 102%. The relative standard deviation, repeatability and stability for this method were not more than 5%. The method could be appied by to analyzing 24 volatiles of H. cordata.2. Metabolic accumulation pattern of H. cordata volatiles at different growth period. Experimental results show that the average concentrations of β-pinene and β-myrcene, which are mainly accumulated in the leaf margin of new leaf, is increasing with growth from one leaf to two leaves. However, the average concentration of β-pinene in petiole is lower, and the average concentration of β-myrcene in the stem is the lowest. Metabolic accumulation of decanal mainly distributes in right leaf margin and its concentration is least in stem growthing one leaf. While H. cordata is growing to two leaves metabolic accumulation of decanal mainly distributes in the end of leaf, and lesser in stem. The concentration of decanal is increasing and the average concentration of decanal is lower from a leaes to two leaves. When H. cordata is growing from three leaves to four leaves, metabolic accumulation of β-pinene and β-myrcene distributes around the stem connected to petiole and the average concentrations of β-pinene and β-myrcene, where the new leaves is more than old leaves, is increasing. Nevertheless, their average concentrations at the point of leaves are lower. At a whole, the average concentration of decanal is increasing, and distribution is well-proportioned relatively from three leaves to four leaves. Metabolic accumulation of 2-undecanone mainly distributes in the leaves and the new leaves are is more than old leaves in the growth process of H. cordata. The concentration of β-pinene, β-myrcene, decanal and 2-undecanone increased markedly when H. cordata is growing to bud stage. Metabolic accoumnlation of β-pinene and β-myrcene distributes mainly in leaves and in the leaf margin, respectively. Metabolic accoumnlation of decanal and 2-undecanone distribute mainly in bud and leaves.Metabolic accoumnlation of cis-3-hexen-1-ol and 2-tetradecanone distribute in bud stage significantly higher than other periods.3. The concentrations of 24 H. cordata volatiles from 72 sample sites at 6 different areas(Danzhai, Fenggang, Guiding, Renhuai, Weng’an, Zhijin) in Guizhou were analyzed. The results obtained show that concentrations of volatiles in different areas are significantly different, and volatiles at the same area are significantly different. The total content of volatiles is the highest at Fenggang, lowest at Weng’an. The concentration of β-pinene, β-myrcene, cis-3-hexenyl-acetate, borneol, 2-tetradecanone and phytol were higher at Danzhai. And the concentration of trans-2-hexenal, cis-3-hexen-1-ol, trans-2-hexen-1-ol, decanal, linalool, β-caryophyllene, 2-undecanone and decanol were higher at Fenggang. The concentration of α-pinene, camphene and bornyl acetate were higher at Guiding. The concentration of γ-terpinene was higher at Renhuai. The concentration of limonene and hexanol were higher at Zhijin.