GC-MS analyses of the volatiles of Houttuynia cordata Thunb.

GC-MS is the basis of analysis of plant volatiles. Several protocols employed for the assay have resulted in inconsistent results in the literature. We developed a GC-MS method, which were applied to analyze 25 volatiles [alpha- pinene, camphene, beta-pinene, 2-methyl-2-pentenal, myrcene, [+]-limonene, eucalyptol, trans-2-hexenal, gamma-terpinene, cis- 3-hexeneyl-acetate, 1-hexanol, alpha-pinene oxide, cis-3-hexen-1-ol, trans-2-hexen-1-ol, decanal, linalool, acetyl-borneol, beta- caryophyllene, 2-undecanone, 4-terpineol, borneol, decanol, eugenol, isophytol and phytol] of Houttuynia cordata Thunb. Linear behaviors for all analytes were observed with a linear regression relationship [r[2]>0.9991] at the concentrations tested. Recoveries of the 25 analytes were 98.56-103.77% with RSDs <3.0%. Solution extraction [SE], which involved addition of an internal standard, could avoid errors for factors in sample preparation by steam distillation [SD] and solidphase micro extraction [SPME]. Less sample material [[almost equal to] 0.05g fresh leaves of H. cordata] could be used to determine the contents of 25 analytes by our proposed method and, after collection, did not affect the normal physiological activity or growth of H. cordata. This method can be used to monitor the metabolic accumulation of H. cordata volatiles

Correlation analysis of nutrients and microorganisms in soils with polyphenols and total flavonoids of Houttuynia cordata / 中国中药杂志

The relationship of nutrients and microorganisms in soils with polyphenols and total flavonoids of Houttuynia cordata were investigated by measuring nutrients, enzyme activity, pH, concentrations of microbe phospholipid fatty acids (PLFAs) in soils, and determining concentrations of polyphenols and total flavonoids of H. cordata. The research is aimed to understand characteristics of the planting soils and improve the quality of cultivated H. cordata. The soils at different sample sites varied greatly in nutrients, enzyme activity, pH, microbic PLFAs and polyphenols and all flavonoids. The content of total PLFAs in sample sites was following: bacteria > fungi > actinomyces > nematode. The content of bacteria PLFAs was 37.5%-65.0% at different sample sites. Activities of polyphenol oxidease, concentrations of available P and content of PLFAs of bacteria, actinomyces and total microorganisms in soils were significantly and positively related to the concentrations of polyphenols and total flavonoids of H. cordata, respectively (P < 0.05) . The Content of fungi PLFAs in soils was significantly and negatively related to concentrations of polyphenols and total flavonoids of H. cordata, respectively (P < 0.05). This study provides evidence that effectiveness of the soil nutrient, which may be improved due to transformation of soil microorganisms and enzymes to N and P in the soils, was beneficial to adaptation of H. cordata adapted to different soil conditions, and significantly affects metabolic accumulation of polyphenols and flavonoids of H. cordata.

Quality evaluation of Houttuynia cordata Thunb. by high performance liquid chromatography with photodiode-array detection [HPLC-DAD]

A new, validated method, developed for the simultaneous determination of 16 phenolics [chlorogenic acid, scopoletin, vitexin, rutin, afzelin, isoquercitrin, narirutin, kaempferitrin, quercitrin, quercetin, kaempferol, chrysosplenol D, vitexicarpin, 5-hydroxy-3,3',4',7-tetramethoxy flavonoids, 5-hydroxy-3,4',6,7-tetramethoxy flavonoids and kaempferol-3,7,4'-trimethyl ether] in Houttuynia cordata Thunb. was successfully applied to 35 batches of samples collected from different regions or at different times and their total antioxidant activities [TAAs] were investigated. The aim was to develop a quality control method to simultaneously determine the major active components in H. cordata. The HPLC-DAD method was performed using a reverse-phase C[18] column with a gradient elution system [acetonitrilemethanol-water] and simultaneous detection at 345 nm. Linear behaviors of method for all the analytes were observed with linear regression relationship [r[2]>0.999] at the concentration ranges investigated. The recoveries of the 16 phenolics ranged from 98.93% to 101.26%. The samples analyzed were differentiated and classified based on the contents of the 16 characteristic compounds and the TAA using hierarchical clustering analysis [HCA] and principal component analysis [PCA]. The results analyzed showed that similar chemical profiles and TAAs were divided into the same group. There was some evidence that active compounds, although they varied significantly, may possess uniform anti-oxidant activities and have potentially synergistic effects

Chemical constituents of Psammosilene tunicoides and bacteriostatic activity / 中国中药杂志

<p><b>OBJECTIVE</b>To study the chemical constituents and bacteriostatic activity of Psammosilene tunicoides.</p><p><b>METHOD</b>Such methods as silica gel column chromatography and gel column chromatography were adotped separate and purify the compounds, and their structures were indentified on the basis of their spectral data and physicochemical properties.</p><p><b>RESULT</b>Ten compounds were separated from ethanol extracts and identified as methyl-4-hydroxybenzoate (1), N-methylsaccharin (2), 3-hydroxy-4-methoxybenzoic acid (3), germanicol (4), tricosanoic acid (5), octacosane (6), amber acid (7), succinic acid (8), stellarine A (9), and oleanane-12-ene-3alpha, 16alpha-two hydroxy-23,28-acid (10).</p><p><b>CONCLUSION</b>All compounds except compound 10 were separated from P. tunicoides for the first time. Compounds 8 and 9 showed the bacteriostatic activity to a certain extent.</p>