Alisma genus: Phytochemical constituents, biosynthesis, and biological activities

The genus Alisma contains 11 species distributed worldwide, of which at least two species (A. orientale [Sam.] Juzep. and A. plantago-aquatica Linn.) have been used as common herbal medicines. Secondary metabolites obtained from the genus Alisma are considered to be the material basis for the various biological functions and medicinal applications. In this review, we mainly focused on the recent investigations of secondary metabolites from plants of the genus Alisma and their biological activities, with the highlighting on the diversity of the chemical structures, the biosynthesis of interesting secondary metabolites, the biological activities, and the relationships between structures and bioactivities.

A 90-Day Repeated Oral Dose Toxicity Study of Alismatis Rhizoma Aqueous Extract in Rats

Alismatis rhizoma (AR), the dried rhizome of Alisma orientale (Sam.) Juzep, is a well-known, traditional medicine that is used for the various biological activities including as a diuretic, to lower cholesterol and as an anti-inflammatory agent. The present study was carried out to investigate the potential toxicity of the Alismatis rhizoma aqueous extract (ARAE) following 90-day repeated oral administration to Sprague-Dawley rats. ARAE was administered orally to male and female rats for 90 days at 0 (control), 500, 1,000 and 2,000 mg/kg/day (n = 10 for male and female rats for each dose). Additional recovery groups from the control group and high dose group were observed for a 28-day recovery period. Chromatograms of ARAE detected main compounds with four peaks. Treatment-related effects including an increase in the red blood cells, hemoglobin, hematocrit, albumin, total protein, and urine volume were observed in males of the 2,000 mg/kg/day group (p < 0.05). However, the diuretic effect of ARAE was considered, a major cause of hematological and serum biochemical changes. The oral no-observed-adverse-effect level (NOAEL) of the ARAE was > 2,000 mg/kg/day in both genders, and no target organs were identified.

Traditional uses, phytochemistry, pharmacology, toxicology and quality control of Alisma orientale (Sam.) Juzep: a review

ETHNOPHARMACOLOGICAL RELEVANCE

Rhizoma alismatis (simplified as RA, "Zexie" in Chinese, ) is a well-known natural medicine with long history in Chinese medicine. As a traditional medicine in China, RA is an important part of many prescriptions and has been commonly used for treating a wide range of ailments related to dysuria, edema, nephropathy, hyperlipidaemia, diabetes, inflammation as well as tumor in clinical applications. Based on scientific literatures, the present paper aims to provide comprehensive and up-to date information about the traditional uses, phytochemistry, pharmacology, toxicology and quality control of RA as well as critical analysis of the research. The review will provide a new foundation and direction for the further studies of RA.

MATERIALS AND METHODS

All available information about RA was supplied by library database and electronic search (ScienceDirect, Web of Science, Pubmed, Google Scholar, etc.). The different types of useful information were collected and arranged in corresponding part of the paper.

RESULTS

Phytochemical studies showed that the main chemical composition of RA was the terpenoid including sesquiterpene, diterpene and triterpene. The crude extracts and isolated compounds from RA showed diverse pharmacological activities including diuretic, nephroprotective, anti-hyperlipidemic, anti-atherosclerotic, anti-cancer, anti-inflammatory and anti-oxidative activities. However, high-dose or long-term use of RA can lead to water-electrolyte imbalance, bloody urine, acidosis and even hepatotoxicity or nephrotoxicity, which have been proven by several studies.

CONCLUSIONS

Pharmacological researches show RA possessing various bioactivities including diuresis, nephroprotective effect, anti-hyperlipidemia, etc. However, more bioactive components especially diuretic and nephroprotective compounds need to be isolated and identified, and more rigorous researches on action mechanisms are required. More experiments in vitro or in vivo and clinical studies are encouraged to clarify correlation between traditional uses and modern applications, and the toxicity need to be further and precisely explored. In addition, a standardized fingerprint for RA is indispensable and emergent. These achievements will further expand to therapeutic potential and usage of RA and provide a powerful support for clinical use.