Kun Jiang1, Qian Song2, Lei Wang3, Tianzhu Xie4, Xi Wu5, Ping Wang6, Guo Yin7, Wencai Ye8, Tiejie Wang9. 1. Institute of Traditional Chinese Medicine & Natural Products, Jinan University, Guangzhou 510632, China; Shenzhen Engineering Laboratory of Exploitation and Utilization of Medicinal Material Resources in Lingnan, Shenzhen 518057, China; Shenzhen Key Laboratory of Drug Quality Standard Research, Shenzhen 518057, China; Shenzhen Institute for Drug Control, Road Gao Xin middle 2nd, No.28, Shenzhen 518057, China. 2. Shenzhen Institute for Drug Control, Road Gao Xin middle 2nd, No.28, Shenzhen 518057, China; Department of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China. 3. Institute of Traditional Chinese Medicine & Natural Products, Jinan University, Guangzhou 510632, China; Shenzhen Engineering Laboratory of Exploitation and Utilization of Medicinal Material Resources in Lingnan, Shenzhen 518057, China. 4. Shenzhen Institute for Drug Control, Road Gao Xin middle 2nd, No.28, Shenzhen 518057, China. 5. Shenzhen Engineering Laboratory of Exploitation and Utilization of Medicinal Material Resources in Lingnan, Shenzhen 518057, China; Shenzhen Institute for Drug Control, Road Gao Xin middle 2nd, No.28, Shenzhen 518057, China. 6. Shenzhen Key Laboratory of Drug Quality Standard Research, Shenzhen 518057, China; Shenzhen Institute for Drug Control, Road Gao Xin middle 2nd, No.28, Shenzhen 518057, China. 7. Shenzhen Engineering Laboratory of Exploitation and Utilization of Medicinal Material Resources in Lingnan, Shenzhen 518057, China; Shenzhen Key Laboratory of Drug Quality Standard Research, Shenzhen 518057, China; Shenzhen Institute for Drug Control, Road Gao Xin middle 2nd, No.28, Shenzhen 518057, China. 8. Institute of Traditional Chinese Medicine & Natural Products, Jinan University, Guangzhou 510632, China; Shenzhen Engineering Laboratory of Exploitation and Utilization of Medicinal Material Resources in Lingnan, Shenzhen 518057, China. Electronic address: chyewc@gmail.com. 9. Shenzhen Engineering Laboratory of Exploitation and Utilization of Medicinal Material Resources in Lingnan, Shenzhen 518057, China; Shenzhen Key Laboratory of Drug Quality Standard Research, Shenzhen 518057, China; Shenzhen Institute for Drug Control, Road Gao Xin middle 2nd, No.28, Shenzhen 518057, China; Department of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China. Electronic address: szyjwtj@163.com.
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE: Exocarpium Citri grandis (C. grandis, Huajuhong in Chinese), the epicarp of C. grandis 'Tomentosa', is used as an antitussive, expectorant and anti-inflammatory drug for hundreds of years in China. The study was aimed at evaluating the antitussive, expectorant and anti-inflammatory effects of different extracts of C. grandis, providing experimental evidence for its traditional use, and laying a foundation for its further researches. MATERIALS AND METHODS: Crude drugs of C. grandis were extracted with four kinds of solvents (water, 50% ethanol, 70% ethanol and 90% ethanol) in reflux conditions, respectively. Solutions were concentrated in reduced pressure and lyophilized in vacuum to yield the aqueous extract, 50% ethanolic extract, 70% ethanolic extract, and 90% ethanolic extract of C. grandis. Antitussive evaluations were carried out with ammonia liquor induced mice cough; expectorant effects were tested with phenol red secretion experiments in mice; anti-inflammatory effects were assessed by murine model of xylene induced ear edema in mice. RESULTS: Only aqueous and 70% ethanolic extracts of C. grandis displayed significant antitussive, expectorant and anti-inflammatory activities. Aqueous extract of C. grandis significantly decreased cough frequency caused by ammonia liquor, increased phenol red secretion and inhibited the development of ear edema in anti-inflammatory assay at the dose of 1005 mg/kg (P<0.05). However, aqueous extract of C. grandis did not lengthened the cough period. It was worth noting that, 70% ethanolic extract of C. grandis showed strong effect of decreasing cough frequency, prolonging cough period, increasing phenol red secretion and decreasing the extent of ear edema at the dose of 493 mg/kg (P<0.001). The low, middle, and high dose (247, 493, and 986 mg/kg) of 70% ethanolic extract of C. grandis showed significant antitussive, expectorant and anti-inflammatory effects in good dose dependant manner. CONCLUSION: The results supported the folk use of C. grandis (decoction of C. grandis) with scientific evidence, and indicated that the 70% ethanolic extract of C. grandis might have better effects of antitussive, expectorant and anti-inflammatory than those of aqueous extract. Further investigation needs to be conducted to study the bioactive constituents of 70% ethanolic extract of C. grandis and the mechanism of observed antitussive, expectorant and anti-inflammatory activities.
ETHNOPHARMACOLOGICAL RELEVANCE: Exocarpium Citri grandis (C. grandis, Huajuhong in Chinese), the epicarp of C. grandis 'Tomentosa', is used as an antitussive, expectorant and anti-inflammatory drug for hundreds of years in China. The study was aimed at evaluating the antitussive, expectorant and anti-inflammatory effects of different extracts of C. grandis, providing experimental evidence for its traditional use, and laying a foundation for its further researches. MATERIALS AND METHODS: Crude drugs of C. grandis were extracted with four kinds of solvents (water, 50% ethanol, 70% ethanol and 90% ethanol) in reflux conditions, respectively. Solutions were concentrated in reduced pressure and lyophilized in vacuum to yield the aqueous extract, 50% ethanolic extract, 70% ethanolic extract, and 90% ethanolic extract of C. grandis. Antitussive evaluations were carried out with ammonia liquor induced mice cough; expectorant effects were tested with phenol red secretion experiments in mice; anti-inflammatory effects were assessed by murine model of xylene induced ear edema in mice. RESULTS: Only aqueous and 70% ethanolic extracts of C. grandis displayed significant antitussive, expectorant and anti-inflammatory activities. Aqueous extract of C. grandis significantly decreased cough frequency caused by ammonia liquor, increased phenol red secretion and inhibited the development of ear edema in anti-inflammatory assay at the dose of 1005 mg/kg (P<0.05). However, aqueous extract of C. grandis did not lengthened the cough period. It was worth noting that, 70% ethanolic extract of C. grandis showed strong effect of decreasing cough frequency, prolonging cough period, increasing phenol red secretion and decreasing the extent of ear edema at the dose of 493 mg/kg (P<0.001). The low, middle, and high dose (247, 493, and 986 mg/kg) of 70% ethanolic extract of C. grandis showed significant antitussive, expectorant and anti-inflammatory effects in good dose dependant manner. CONCLUSION: The results supported the folk use of C. grandis (decoction of C. grandis) with scientific evidence, and indicated that the 70% ethanolic extract of C. grandis might have better effects of antitussive, expectorant and anti-inflammatory than those of aqueous extract. Further investigation needs to be conducted to study the bioactive constituents of 70% ethanolic extract of C. grandis and the mechanism of observed antitussive, expectorant and anti-inflammatory activities.
Authors: Zhangyong Dong; Ishara S Manawasinghe; Yinghua Huang; Yongxin Shu; Alan J L Phillips; Asha J Dissanayake; Kevin D Hyde; Meimei Xiang; Mei Luo Journal: Front Microbiol Date: 2021-02-09 Impact factor: 5.640