Rhododendron dauricum

Background

Chinese Name (pinyin): Manshanhong

Chinese Name  :

Common Name  :Dahurian Rhododendron Leaf

Specific Name  : Folium rhododendri daurici

Scientific Name:
Collection  : The drug is collected in summer and autumn and dried in the shade.

Description  : Mostly recurved, tubular, sometimes crumpled and broken, when whole, elliptical or long obovate, 2 - 7.5cm long, 1 - 3cm wide, apex obtuse, base subrounded or broadly cuneate, margin entire, upper surface dark green or brownish green, scattered with pale glandular scales, lower surface greyish green, glandular scales numerous. Petioles 3 - 10mm long, texture nearly leathery, odor, aromatic and characteristic, taste relatively bitter and slightly pungent.

Identification  : 1.Transverese section: Upper epidermal cells rectangular, covered with cuticle bearing glandular scales, lower epidermal cells subrounded with sinuous walls, stomata and galndular scales. Palisade tissue of 2 - 3 rows of cells, spongy cells subrounded. Vascular bundle of midrib bicollateral, pericyclic fibres arranged in an interrupted ring, numerous rows of collenchymatous cells occurring inside the upper and lower epidermis, the upper epidermis of midrib bearing unicellular non-glandular hairs. Parenchymatous cells and spongy cellss containing clusters of calcium oxalate.2.Heat under reflux 5g of the drug in 50ml of ethanol for 1 hour, filtrate, evaporate the filtrate to dryness, dissolve the residue by heating in 10ml of saturated sodium carbonate solution, filter and adjust pH to 2 - 3 with hydrochloric acid. Extract with 2 quantities, each of 15ml of ether. Combine the ether extract, evaporate ether to about 1ml as the test solution. Dissolve farrerol CRS in ether to prepare a solution containing 0.5mg per ml as the reference solution. Carry out the method for thin layer chromatograpghy (Appendix Vl B) using silica gel G as the coating substance and upper layer of toluene-ethyl acetate-formic acid (7:2:0.5) as the mobile phase. Apply separately 5µl of the two solutions to the plate, allow to be presaturated in the chamber for 15 minutes. After developing and removal of plate, dry it in the air, spray with aluminum chloride TS, examine under ultra violet light (365nm), the fluorescent spot in the chromatogram obtained with the test solution correspond in position and color to the spot in the chromatogram obtained with the reference solution.Assay Standard Preparation: weigh accurate 6mg of rutin CRS, previously dried in vacuum over phosporous pentoxide to constant weight, dissolve in an appropriate quantity of 60% ethanol and dilute to volume, mix well, use as the standard solution (containing 60 µg of anhydrous rutin per ml)Preparation of standard curve: measure accurately 0.5, 1.0, 2.0, 3.0, and 4.0 ml of standard soution in 10ml volumetric flask separately, add 2ml of 0.1mol/L aluminum chloride solution, 3ml of 1mol/L potassium acetate solution to each flask, dilute with 60% ethanol to volume, mix well and allow to stand for 30 minutes. Carry out the method for spectrophotometry (Appendix V B) measure the absobance at 420nm taking the reagent solution as a blank, plot the standard curve, using absorbance as ordinate and concentration as abscissa.Procedure: Measure accurately 1g of the coarse powder in a round bottom flask, add accurately 50ml of 60% ethanol and weigh. Heat under reflux for 1 hour, cool, weigh again and compansate the loss of the weight with 60% ethanol, shake thoroughly, filter and discard the initial filtrate. Measure accurately 5ml of the successive filtrate to a 25ml volumetric flask, dilute with 60% ethanol to volumn. Transfer accurately 1ml of above solution to a 10ml volumetric flask, carry out the procedure as describe under preparation of standard curve, beginning at the words "add 2ml of 0.1mol/L aluminum chloride solution?", measure the absorbance, read out the weight of rutin (µg) in the test solution from the standard curve, calculate the content fo rutin (C27H30O16). It contains not less than 2.0% flavonoids calculated as rutin and the dried basis.

Processing  :

Action  : Antitusiive and expectorant.

Indication  : acute and chronic bronchitis

Precautions  :

Dosage  : 25 to 50 g in aquenous decoction; 6 to 12 g macerated with 40% ehtanol.

Storage  : Preserve in a cool and dry place, protected from moisture and heat.

Background

Chinese Name (pinyin): Manshanhongyou

Chinese Name  :

Common Name  :Dahurian Rhododendron oil

Specific Name  : Oleum rhododendri daurici

Scientific Name:
Collection  :

Description  : A pale yellowish yellowish-green to yellowish brown clear liquid with crystal separating out when cooled below -10ºC. Odour, strongly irritant and aromatic; taste cool and pungent.Relatively density: 0.935 - 0.950 (Appendix Vll A)Refractive index: 1.500-1.520 (Appendix Vll F)Identification: To 0.1ml, add 0.5ml of ethanol, mix well. Add 2 drops of 1% solution of vanillin in sulfuric acid, shake well, a purplish-red to dark purplish-red color is produced.

Identification  : To 1ml of the oil add 10ml of hydrochloric acid containing 0.1g of sucrose, shake for 30 seconds, the acid layer appears pink colour which becomes red gradually on standing.Heating test: Carry out the method for heating test (Appendix lX N) using 50 ml of the oil, no precipitate is produced.Foreign matter: Not more than 0.2% (Appendix lX N)Water and volatile matter: Not mre than 0.2% (Appendix lX N).

Processing  :

Action  : Antitussive and expextorant.

Indication  : acute and chronic bronchitis

Precautions  :

Dosage  : 0.05 to 0.1g, two or three times a day.

Storage  : Preserve in tightly closed containers, stored in a cool place, and protected from light.

Evidence or the Use of Rhododendron dauricum in the Treatment of Epilepesy

1st Five Results: pubmed search

Dan Wang, Guiling Liu, Juan Yang, Gongfa Shi, Zhaoqian Niu, Huijun Liu, Nuo Xu, Ling Wang
Integrated metabolomics and transcriptomics reveal molecular mechanisms of corolla coloration in Rhododendron dauricum L.
Plant Physiol Biochem: 2024, 207;108438
[PubMed:38367387] [WorldCat.org] [DOI] (I p)

Ying Wu, Xin Yu, Hongying Gao, Peipei Gao, Zhihong Gao
##Title##
Nat Prod Res: 2024;1-6
[PubMed:38300706] [WorldCat.org] [DOI] (I a)

Jin Liu, Yang Xu, Yan-Ji Si, Bin-Qi Li, Peng Chen, Ling-Ling Wu, Pu Guo, Rui-Qing Ji
##Title##
J Fungi (Basel): 2024, 10(1);
[PubMed:38248974] [WorldCat.org] [DOI] (I e)

Shijia Wang, Yafen Guo, Xiaoyang Cui
Effects of nitrogen addition on greenhouse gas fluxes during continuous freeze-thaw cycles in a cold temperate forest.
Environ Sci Pollut Res Int: 2023, 30(38);88406-88416
[PubMed:37438500] [WorldCat.org] [DOI] (I p)

Yuanyuan Feng, Hanqi Zhang, Biao Gao, Guijuan Zheng, Suqin Zha, Guangmin Yao
Highly oxygenated grayanane diterpenoids with structural diversity from the flowers of Rhododendron dauricum and their analgesic activities.
Bioorg Chem: 2023, 132;106374
[PubMed:36682149] [WorldCat.org] [DOI] (I p)