Physicochemical and elemental studies of Hydrocotyle javanica Thunb. for standardization as herbal drug

Objective: To explore the leaves of Hydrocotyle javanica Thunb. as a source of safe and effective antibacterial herbal medicine.Methods: The standardization was validated by stepwise physicochemical studies,element analysis, determination of ash values, fluorescence analysis, assessment of moisture content, extractive values in different solvent systems and extraction methods.Heavy metal contents, mineral and element contents were analysed by atomic absorption spectrophotometry, inductively coupled plasma-mass spectrometer and CHNS/O analyser, respectively.Results: The methanol extract of the folklore medicinal plant having antibacterial efficacy contained flavonoids and phenolic OH groups. The ICP multi standard indicated the presence of three major compounds with molecular mass of 161 190 and 221 Da. Heavy metals viz. lead, mercury and copper content were 4.38 ppm, < 0.05 ppm and 24.70 ppm,respectively. Minerals content of calcium, phosphorus, potassium and iron were 1 190.94 mg/100 g, 375.57 mg/100 g, 2 820 mg/100 g and 340.20 mg/100 g of plant sample, respectively. Elements like carbon, hydrogen, nitrogen and sulphur contents were38.18%, 5.67%, 2.23% and 0.51%, respectively. Heavy metal profile of the tested plant was within the permissible limits of the regulatory authorities.Conclusions: Hence the present physicochemical and elements studies reveals that the plant Hydrocotyle javanica Thunb. could be a potent source of herbal preparation as well as a safe and novel synthetic antibacterial drug.

Evaluation of antioxidant enzymes activities and identification of intermediate products during phytoremediation of an anionic dye(C.I. Acid Blue 92) by pennywort(Hydrocotyle vulgaris)

The potential of pennywort （Hydrocotyle vulgaris） for phytoremediation of C.I. Acid Blue 92 （AB92） was evaluated. The effects of various experimental parameters including pH, temperature, dye concentration and plant weight on dye removal efficiency were investigated. The results showed that the optimal condition for dye removal were pH 3.5 and temperature 25~C. Moreover, the absolute dye removal enhanced with increase in the initial dye concentration and plant weight. Pennywort showed the same removal efficiency in repeated experiments （four runs） as that obtained from the first run （a 6-day period）. Therefore, the ability of the plant in consecutive removal of AB92 confirmed the biodegradation process. Accordingly, a number of produced intermediate compounds were identified. The effect of treatment on photosynthesis and antioxidant defense system including superoxide dismutase, peroxidase and catalase in plant roots and leaves were evaluated. The results revealed a reduction in photosynthetic pigments content under dye treatments. Antioxidant enzyme responses showed marked variations with respect to the plant organ and dye concentration in the liquid medium. Overall, the increase in antioxidant enzyme activity under AB92 stress in the roots was much higher than that in the leaves. Nevertheless, no significant increase in malondialdehyde content was detected in roots or leaves, implying that the high efficiency of antioxidant system in the elimination of reactive oxygen species. Based on these results, pennywort was founded to be a capable species for phytoremediation of AB92-contaminated water, may be effective for phytoremediation dye-contaminated polluted aquatic ecosystems.

克隆整合对天胡荽分株间有性和克隆繁殖策略的影响

研究了克隆整合特性对天胡荽在异质性土壤养分环境中繁殖策略的影响。结果表明:克隆整合可显著提高相连分株中处于低资源条件下近端分株的结果数和坐果率、总种子数量,及其单个克隆分株的平均结籽数,但对各处理单果重量的无显著影响。克隆整合有利于促进资源缺乏端的有性繁殖;促进生理顶端分株的克隆繁殖。在低资源条件下,克隆整合促进近端分株的有性繁殖以及远端分株的克隆繁殖;相反则促进远端分株的有性繁殖和克隆繁殖。因此,克隆整合特性是天胡荽对异质性环境的重要适应对策,它使天胡荽能够扩展到不适合植物生长的低养分斑块中,从而增加了天胡荽对恶劣环境的繁殖适合度及适应能力。

铜钱草对城市生活污水的净化效果

以铜钱草(Hydrocotyle vulgaris L.)为试材,在3种浓度梯度的城市生活污水中进行培养,研究了铜钱草对城市生活污水的处理效果.结果表明,铜钱草在3种浓度的城市生活污水中均生长良好,其株高、根长及生物量均有显著增加;铜钱草对高质量浓度(CODCr 287.21 mg/L,TN 14.68 mg/L,TP 3.87 mg/L)、中质量浓度(CODCr 191.62 mg/L,TN 9.69 mg/L,TP 2.74 mg/L)和低质量浓度(CODCr 139.24 mg/L,TN 6.94 mg/L,TP1.46 mg/L)城市生活污水中CODCr的去除率分别为94.99%、84.97%和88.71%;对TN的去除率分别为76.85%、65.24%和57.34%;对TP的去除率分别为92.17%、84.71%和73.24%.表明铜钱草对城市生活污水具有良好的净化效果,可作为城市生活污水治理的优良物种进行推广.