https://bioone.org/journals/harvard-papers-in-botany/volume-13/issue-2/1043-4534-13.2.299/Flora-of-China/10.3100/1043-4534-13.2.299.pdf

Flora of China

A number of essential oils are currently in use as aromatherapy agents to relieve anxiety, stress, and depression Popular anxiolytic oils include lavender (Lavandula angustifolia), rose (Rosa damascena), orange (Citrus sinensis), bergamot (Citrus aurantium), lemon (Citrus limon), sandalwood (Santalum album), clary sage (Salvia sclarea), Roman chamomile (Anthemis nobilis), and rose-scented geranium (Pelargonium spp) This review discusses the chemical constituents and CNS effects of these aromatherapeutic essential oils, as well as recent studies on additional essential oils with anxiolytic activities

https://journals.sagepub.com/doi/pdf/10.1177/1934578X0900400928

Essential oils and anxiolytic aromatherapy.

The adulteration of herbal products is a threat to consumer safety. Here we surveyed the species composition of commercial Rhodiola products using DNA barcoding as a supervisory method. A Rhodiola dietary supplement DNA barcode database was successfully constructed using 82 voucher samples from 10 Rhodiola species. Based on the DNA barcoding standard operating procedure (SOP), we used this database to identify 100 Rhodiolae Crenulatae Radix et Rhizoma decoction piece samples that were purchased from drug stores and hospitals. The results showed that only 36 decoction piece sequences (40%) were authentic R. crenulata, which is recorded in Chinese Pharmacopeia, whereas the other samples were all adulterants and may indicate a potential safety issue. Among the adulterants, 35 sequences (38.9%) were authenticated as R. serrata, nine sequences (10%) were authenticated as R. rosea, which is documented in the United States Pharmacopeia, and the remaining samples were authenticated as other three Rhodiola species. This result indicates decoction pieces that are available in the market have complex origins and DNA barcoding is a convenient tool for market supervision.

/pdf/survey-of-commercial-rhodiola-products-revealed-species-35b8gq2zh7.pdf

Survey of commercial Rhodiola products revealed species diversity and potential safety issues

Complete Pathway Elucidation and Heterologous Reconstitution of Rhodiola Salidroside Biosynthesis

Rheum officinale Baill., an important but endangered medicinal herb, is endemic to China. Inter-simple sequence repeat (ISSR) markers were employed to investigate the genetic diversity and differentiation of 12 populations of R. officinale. Thirteen selected primers yielded 189 bright and discernible bands, with an average of 14.54 per primer. The genetic diversity was low at the population level, but pretty high at the species level (H = 0.1008, I = 0.1505, PPB = 28.95% vs. H = 0.3341, I = 0.5000, PPB = 95.24%, respectively) by POPGENE analysis. Analysis of molecular variance (AMOVA) showed that the genetic variation was found mainly among populations (74.38%), in line with the limited gene flow (Nm = 0.2766) among populations. Mantel test revealed a significant correlation between genetic and geographic distances (r = 0.5381, P = 0.002), indicating the role of geographic isolation in shaping the present population genetic structure. Both Bayesian analysis and UPGMA cluster analysis demonstrated the similar results. Our results imply that the conservation efforts should aim to preserve all the extant populations of this endangered species, and cultivation is proposed in this study.

/pdf/genetic-diversity-of-the-endemic-and-medicinally-important-10g02vago2.pdf

Genetic diversity of the endemic and medicinally important plant Rheum officinale as revealed by Inter-Simpe Sequence Repeat (ISSR) Markers.

The plant Rhodiola crenulata is a perennial herbaceous species distributed in the plateau region of southwestern China, especially the Hengduan Mountains region. It has been one of the most important traditional herbal remedies in Tibet for more than one thousand years, but the accelerated and uncontrolled collection of this plant since the 1980s has lead to deforestation. We used inter-simple sequence repeats (ISSR) to assess levels of genetic variation in R. crenulata from nine diverse natural populations in eastern Tibet and northern Yunnan, the first time such a study has been carried out. The 12 primers we used were able to detect 184 polymorphic loc. Analysis of molecular variance (AMOVA) indicated that species level genetic diversity was relatively high (p = 97.83%, and Ho = 0.464) and analysis using Shannons index showed that the within and between genetic diversity of R. crenulata are approximately equal. Neis genetic distance and unweighted pair-group method with arithmetic averages (UPGMA) cluster analysis showed that the three populations from Tibet and the six populations from Yunnan form two major clusters. The Yunnan populations from three locations were further divided into three corresponding groups, indicating that genetic differentiation was correlated to geographic distribution. Understanding the genetic structure of R. crenulata provides insight for the conservation and management of this endangered species.

http://www.scielo.br/pdf/gmb/v29n2/a23v29n2.pdf

Determination of genetic variation in Rhodiola crenulata from the Hengduan Mountains Region, China using inter-simple sequence repeats

As a N2-fixing tree species, sea buckthorn (Hippophae rhamnoides) is well adapted to arid regions and is utilized for multiple purposes in China. Current knowledge of genetic variability of H. rhamnoides is limited in terms of rangewide distributions. Eleven natural populations of sea buckthorn in northeastern and northwestern China were analyzed to detect genetic variation among and within populations, by use of ISSR (inter-simple sequence repeats) markers. Using eight primers, 207 polymorphic loci were observed, ranging in size from 250 to 2500 bp. The coefficient of gene differentiation (Gst = 0.0679) showed that the total molecular variance of 11 populations was mainly existed within populations. The genetic variation within and among the 11 populations was 93.21 and 6.79%, respectively. No significant correlation between genetic and geographic distances of the populations was found using ISSR markers. Our study provides a population-level genetic profile for further investigation and conservation of genetic diversity of sea buckthorn.

Genetic diversity of sea buckthorn (Hippophae rhamnoides) populations in northeastern and northwestern China as revealed by ISSR markers

The essential oils from rhizomes of Rhodiola crenulata and R. fastigiata in eastern Tibet were analyzed by using GC-MS. The major constituents were geraniol (53.3%), n-octanol (13.4%), 2-methyl-3-buten-2-ol (10.8%), citronellol (5.3%), 3-methyl-2-buten-1-ol (4.0%), myteol (3.0%), and linalool (2.4%) for R. crenulata and geraniol (45.3%), n-octanol (12.3%), 2-methyl-3-buten-2-ol (8.0%), linalool (5.1%), isogeraniol (4.5%), citronellol (4.4%), and cis-sabinenehydrate (3.6%) for R. fastigiata.

/pdf/chemical-composition-of-the-essential-oils-of-two-rhodiola-1x6zfqvnv9.pdf

Chemical composition of the essential oils of two Rhodiola species from Tibet.

Interpopulation variability of rhizome essential oils in Rhodiola crenulata from Tibet and Yunnan, China

In this paper, the internal transcribed spacer (ITS) regions of nuclear ribosomal DNA(nrDNA) were sequenced from six species of Rhodiola in Yunnan. The sequences of the ITS regions ranged from 604 to 617 base pairs (bp). Using Sedum bulbiferum as the outgroup, phylogenetic trees of 22 Rhodiola species were constructed with the maximum parsimony (MP) and the neighbor-joining (NJ) methods. Two clades were then classified in both MP and NJ trees with relatively high bootsrap values.

Yidong Lei

Papers

Determination of genetic variation in Rhodiola crenulata from the Hengduan Mountains Region, China using inter-simple sequence repeats

Genetic diversity of sea buckthorn (Hippophae rhamnoides) populations in northeastern and northwestern China as revealed by ISSR markers

Chemical composition of the essential oils of two Rhodiola species from Tibet.

Interpopulation variability of rhizome essential oils in Rhodiola crenulata from Tibet and Yunnan, China

A Preliminary Phylogenetic Analysis of Some Rhodiola Species Based on nrDNA ITS Sequences