The genus Polygonatum: A review of ethnopharmacology, phytochemistry and pharmacology.

ETHNOPHARMACOLOGICAL RELEVANCE: The genus Polygonatum (Asparagaceae) comprises 71 species distributed throughout the temperate Northern Hemisphere. The medicinal plants of Polygonatum have been traditionally used as tonics in China, India, Pakistan, Iran and Japan, and have been demonstrated to be highly effective in clinical practice for treating age-related diseases, diabetes, lung diseases, fatigue, feebleness and indigestion. AIM OF THE REVIEW: This paper aims to provide the links among traditional uses, chemical constituents, pharmacological effects and toxicity to support their therapeutic potential and uncover opportunities for future research. MATERIALS AND METHODS: The relevant information on the genus Polygonatum was gathered from scientific databases (Google Scholar, Web of Science, SciFinder, ScienceDirect, ACS Publications, PubMed, Wiley Online Library, CNKI). Information was also obtained from online databases, books, Ph.D. dissertations and M.Sc. theses. The literature cited in this review dates from 1917 to June 2017. RESULTS: At least 37 species and 1 variety of Polygonatum plants have been used as traditional medicine and functional food. The major chemical constituents of Polygonatum plants are steroidal saponins, triterpenoid saponins, homoisoflavanones, polysaccharides and lectins. A putative biosynthetic pathway of steroidal saponins and triterpenoid saponins has been established based on the compounds isolated from Polygonatum plants. The crude extracts and certain pure compounds from Polygonatum plants have shown a wide range of pharmacological effects such as anti-aging, anti-diabetic, anti-fatigue, and anticancer effects. The rhizomes of Polygonatum plants have a low degree of toxicity after processing. CONCLUSIONS: Based on this review, some traditional uses of Polygonatum species have been confirmed by pharmacological studies, such as its anti-osteoporosis, neuroprotective, immunomodulatory, anti-diabetic and anti-fatigue effects. Most of the pharmacological effects of this genus can be attributed to its polysaccharides, saponins and lectins. However, to clarify the chemical differences that lead to the different traditional uses between "Huangjing" (derived from P. sibiricum, P. kingianum, P. cyrtonema) and "Yuzhu" (derived from P. odoratum), a systematic comparison of the small molecule compositions and polysaccharides of these four species is needed. In addition to these four species, other locally used medicinal Polygonatum species should be the subject of research, and the chemical and pharmacological relationships of these species should be investigated to expand the medicinal resources and standardize the use of Polygonatum species.

De Novo Assembly and Analysis of Polygonatum sibiricum Transcriptome and Identification of Genes Involved in Polysaccharide Biosynthesis.

Polygonatum sibiricum polysaccharides (PSPs) are used to improve immunity, alleviate dryness, promote the secretion of fluids, and quench thirst. However, the PSP biosynthetic pathway is largely unknown. Understanding the genetic background will help delineate that pathway at the molecular level so that researchers can develop better conservation strategies. After comparing the PSP contents among several different P. sibiricum germplasms, we selected two groups with the largest contrasts in contents and subjected them to HiSeq2500 transcriptome sequencing to identify the candidate genes involved in PSP biosynthesis. In all, 20 kinds of enzyme-encoding genes were related to PSP biosynthesis. The polysaccharide content was positively correlated with the expression patterns of ß-fructofuranosidase (sacA), fructokinase (scrK), UDP-glucose 4-epimerase (GALE), Mannose-1-phosphate guanylyltransferase (GMPP), and UDP-glucose 6-dehydrogenase (UGDH), but negatively correlated with the expression of Hexokinase (HK). Through qRT-PCR validation and comprehensive analysis, we determined that sacA, HK, and GMPP are key genes for enzymes within the PSP metabolic pathway in P. sibiricum. Our results provide a public transcriptome dataset for this species and an outline of pathways for the production of polysaccharides in medicinal plants. They also present more information about the PSP biosynthesis pathway at the molecular level in P. sibiricum and lay the foundation for subsequent research of gene functions.

[Effects of constant low temperature on cold resistance of different strains Polygonatum odoratum].

In this paper, the five strains of Polygonatum odoratum were used as the experimental materials to test the supercooling point, freezing point, the degree of supercooling, the transition stage time, cooling time and water composition of the plant tissue. The cold resistance of P. odoratum was analyzed with the Gray Correlation Method. The results showed that the cold resistances of the five strains of P. odoratum were different, and the water content of plant tissue had some relevance with freezing point and supercooling point, whereas, it could not be measured when the moisture content was too low. The order of cold resistance of the five strains of P. odoratum was ZJCY, DYYZ, XYYZ, CYYZ and JZ I.

[The research on the identification of some polygonatum crude drugs by Fourier transform infrared spectrometry].

The common peak ratio and variant peak ratio were calculated by FTIR spectroscopy of six medicinal plants of polygonatum. The index sequence of common peak ratio and variant peak ratio of six medicinal plants was established and the FTIR spectroscopy was analyzed by cluster analysis, which indicated the sibship of the six medicinal plants, polygonati rhizoma, polygonati odorati rhizoma and their adulterant such as Polygonatum filipes Merr., Polygonatum macropodium Turcz. and Polygonatum humile Fisch Ex Maxim. could be identified by comparing second derivative spectrum of the samples. FTIR with good characteristics such as simple and rapid procedures, nondestructive testing, small amount of sample required, good reproducibility and specificity of fingerprint, provides a new method for identification of polygonati rhizoma, polygonati odorati rhizoma and their adulterant.

[Studies on phonological phases of cultivated Polygonatum].

OBJECTIVE: To determine the phonological phases of cultivated Polygonatum by investigating the dynamic pattern of its growth and development, which would provide the guides for normal planting in the field. METHODS: Fix-point and real-time observation combining with comprehensive survey were used in the field. RESULT: Cultivated Polygonatum had obvious processes of development including emergence of seedlings, extension of leaves, growth of stems and leaves, floral initiation, flowering, seed setting, death of plant-germinating-in-spring, plant shoot regeneration and hibernating shoot emergence, and hibernation with dead aerial part of plant. There were small differences in these processes of development among species and sites, but the whole phonological pattern hold relatively constant. CONCLUSION: The phonological phases of Polygonatum with eight stages, including seedlings emergence stage, plant extension stage, leaves extension stage, anthesis stage, seed stage, aerial part death stage, germination-in-autumn stage, and hibernation stage, were finally determined.