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Ulmus davidiana, commonly known as yugeunpi, has a long history of use in Korea in treating burns, eczema, frostbite, difficulties in urination, inflammation, and psoriasis,1 and has also been used in China for some of these indications, including skin inflammation.2,3 Currently, there are several areas in which the bioactivity of U. davidiana are under investigation, with numerous potential applications in dermatology. This column focuses briefly on the evidence supporting the traditional uses of the plant and potential new applications.
Anti-inflammatory activity
Eom and colleagues studied the potential of a polysaccharide extract from the root bark of U. davidiana to serve as a suitable cosmetic ingredient for conferring moisturizing, anti-inflammatory, and photoprotective activity. In this 2006 investigation, the composition of the polysaccharide extract was found to be primarily rhamnose, galactose, and glucose. The root extract exhibited a similar humectant moisturizing effect as hyaluronic acid, the researchers reported. The U. davidiana root extract was also found to dose-dependently suppress prostaglandin E2. The inhibition of the release of interleukin-6 and IL-8 was also reported to be significant. The use of the U. davidiana extract also stimulated the recovery of human fibroblasts (two times that of positive control) exposed to UVA irradiation. The researchers suggested that their overall results point to the viability of U. davidiana root extract as a cosmetic agent ingredient to protect skin from UV exposure and the inflammation that follows.2
In 2013, Choi and colleagues found that a methanol extract of the stem and root barks of U. davidiana revealed anti-inflammatory properties, with activity attributed to two trihydroxy acids [then-new trihydroxy fatty acid, 9,12,13-trihydroxyoctadeca-10(Z),15(Z)-dienoic acid, and pinellic acid], both of which blocked prostaglandin D₂ production.4
That same year, Lyu and colleagues studied the antiallergic and anti-inflammatory effects of U. davidiana using a 1-fluoro-2,4-dinitrofluorobenzene (DNFB)–induced contact dermatitis mouse model. They found that treatment at a dose of 10 mg/mL successfully prevented skin lesions caused by consistent DNFB application. Further, the researchers observed that topically applied U. davidiana suppressed spongiosis and reduced total serum immunoglobulin and IgG2a levels. Overall, they concluded that the botanical treatment improved contact dermatitis in mice.1
In 2019, So and colleagues studied the chemical components of U. davidiana root bark (isolating a chromane derivative and 22 known substances) and reported data supporting the traditional use of the root bark for gastroenteric and inflammatory indications.3
Bakuchiol [(1E,3S)-3-ethenyl-3,7-dimethyl-1,6-octadien-1-yl]phenol, a prenylated phenolic monoterpene found in the seeds and leaves of various plants, including U. davidiana, is used for its anti-inflammatory properties in traditional Korean medicine.5 Choi and colleagues determined that bakuchiol exhibited robust anti-inflammatory activity in a study of U. davidiana constituents, at least partially accounting for the anti-inflammatory functions of the plant.5
Antifungal activity
In 2021, Alishir and colleagues conducted a phytochemical analysis of the root bark extract of U. davidiana, resulting in the isolation of 10 substances including the novel coumarin glycoside derivative ulmusakidian. Some of the compounds exhibited antifungal activity against Cryptococcus neoformans, though none demonstrated antifungal activity against Candida albicans.6
Wound dressing
Park and colleagues demonstrated in 2020 that superabsorbing hydrogel wound dressings composed of U. davidiana root bark powders, which exhibit gelling activity, performed effectively in speeding up wound closure and cutaneous regeneration in skin-wound mice models. These dressings also displayed thermal stability and superior mechanical properties to pullulan-only gel films. The researchers concluded that gel films composed of U. davidiana have potential to surpass the effectiveness of current products.7
Anti–hair loss activity
Early in 2022, Kwon and colleagues investigated the anti–hair loss mechanism of U. davidiana and determined that supercritical extraction-residues of U. davidiana significantly hinder the secretion of transforming growth factor–beta but dose dependently salvage insulinlike growth factor 1, and substantially decrease dihydrotestosterone synthesis. They concluded that these U. davidiana supercritical fluid extract residues have the potential to halt the loss of human hair.8
Photoprotective potential
Late in 2020, Her and colleagues reported on their development and analysis of a new distillate derived from a fermented mixture of nine anti-inflammatory herbs including U. davidiana. The investigators assessed the effects of the topically applied distillate on UVB-induced skin damage in Institute of Cancer Research mice, finding significant improvements in the dorsal skin photodamage. Application of the distillate also ameliorated collagen production impairment and diminished proinflammatory cytokine levels of tumor necrosis factor (TNF)–alpha and IL-1B. The researchers concluded that this anti-inflammatory herbal distillate, which includes U. davidiana, displays the potential to serve as a photoprotective agent.9
Antiaging activity
In 2011, Yang and colleagues set out to identify constituent substances of the root bark of U. davidiana that have the capacity to suppress cellular senescence in human fibroblasts and human umbilical vein endothelial cells. They isolated 22 compounds, of which epifriedelanol, ssioriside, and catechin-7-O-beta-D-glucopyranoside impeded adriamycin-induced cellular senescence in human dermal fibroblasts and friedelin, epifriedelanol, and catechin-7-O-beta-apiofuranoside in the umbilical vein endothelial cells. Epifriedelanol was the most potent of the substances, leading the researchers to conclude that this U. davidiana component can diminish cellular senescence in human primary cells and has the potential as an oral and/or topical antiaging agent.10
Also that year, in a study on the protective effects of U. davidiana on UVB-irradiated hairless mice, the authors claimed that an ethanol extract of U. davidiana significantly suppressed wrinkle development in mice chronically exposed to UVB.11 This study showed that U. davidiana extract exerts antioxidant activity as evidenced by a decrease in MMP-1 activity. It also demonstrated antielastase activity. The treated mice showed a decrease in wrinkles as compared with water-treated mice.11 Although this is just one study in mice, it may demonstrate a protective effect on elastic fibers on skin exposed to UVB light.
Late in 2020, Lee and colleagues reported on their study of the possible antiaging effects on the skin of (-)-phenolic compounds isolated from the root bark of U. davidiana. The function of collagenase MMP-1 was found to be inhibited by the isolate (-)-catechin, which also halted collagen degradation caused by TNF-alpha in normal human dermal fibroblasts. Further, the investigators demonstrated that the U. davidiana isolate (-)-catechin reduced the expression of proinflammatory cytokines such as IL-1B and IL-6. They concluded that the U. davidiana isolate exhibits the potential to combat intrinsic as well as extrinsic cutaneous aging.12
These findings are particularly intriguing. There is much overlap between intrinsic and extrinsic aging. If U. davidiana can keep collagen intact and inhibit cellular senescence, it may serve as an early intervention toward slowing or preventing skin aging.
Summary
Of greatest interest now, perhaps, is its potential to impede cellular senescence. Senescent cells release a multitude of inflammatory and other factors that hasten intrinsic aging. Blocking cellular senescence is an important approach to the prevention and treatment of skin aging.
Dr. Baumann is a private practice dermatologist, researcher, author, and entrepreneur in Miami. She founded the division of cosmetic dermatology at the University of Miami in 1997. The third edition of her bestselling textbook, “Cosmetic Dermatology,” was published in 2022. Dr. Baumann has received funding for advisory boards and/or clinical research trials from Allergan, Galderma, Johnson & Johnson, and Burt’s Bees. She is the CEO of Skin Type Solutions, a SaaS company used to generate skin care routines in the office and as an ecommerce solution. Write to her at dermnews@mdedge.com.
References
1. Lyu J et al. J Pharmacopuncture. 2013 Jun;16(2):41-5.
2. Eom SY et al. J Cosmet Sci. 2006 Sep-Oct;57(5):355-67.
3. So HM et al. Bioorg Chem. 2019 Oct;91:103145.
4. Choi HG et al. Phytother Res. 2013 Sep;27(9):1376-80.
5. Choi SY et al. J Med Food. 2010 Aug;13(4):1019-23.
6. Alishir A et al. Bioorg Med Chem Lett. 2021 Mar 15;36:127828.
7. Park TH et al. Saudi Pharm J. 2020 Jul;28(7):791-802.
8. Kwon YE et al. Molecules. 2022 Feb 19;27(4):1419.
9. Her Y et al. Molecules. 2020 Dec 29;26(1):124.
10. Yang HH et al. Planta Med. 2011 Mar;77(5):441-9.
11. Kim YO et al. Korean Journal of Medicinal Crop Science. 2011;19(6):508-13.
12. Lee S et al. Antioxidants (Basel). 2020 Oct 13;9(10):981.
Ulmus davidiana, commonly known as yugeunpi, has a long history of use in Korea in treating burns, eczema, frostbite, difficulties in urination, inflammation, and psoriasis,1 and has also been used in China for some of these indications, including skin inflammation.2,3 Currently, there are several areas in which the bioactivity of U. davidiana are under investigation, with numerous potential applications in dermatology. This column focuses briefly on the evidence supporting the traditional uses of the plant and potential new applications.
Anti-inflammatory activity
Eom and colleagues studied the potential of a polysaccharide extract from the root bark of U. davidiana to serve as a suitable cosmetic ingredient for conferring moisturizing, anti-inflammatory, and photoprotective activity. In this 2006 investigation, the composition of the polysaccharide extract was found to be primarily rhamnose, galactose, and glucose. The root extract exhibited a similar humectant moisturizing effect as hyaluronic acid, the researchers reported. The U. davidiana root extract was also found to dose-dependently suppress prostaglandin E2. The inhibition of the release of interleukin-6 and IL-8 was also reported to be significant. The use of the U. davidiana extract also stimulated the recovery of human fibroblasts (two times that of positive control) exposed to UVA irradiation. The researchers suggested that their overall results point to the viability of U. davidiana root extract as a cosmetic agent ingredient to protect skin from UV exposure and the inflammation that follows.2
In 2013, Choi and colleagues found that a methanol extract of the stem and root barks of U. davidiana revealed anti-inflammatory properties, with activity attributed to two trihydroxy acids [then-new trihydroxy fatty acid, 9,12,13-trihydroxyoctadeca-10(Z),15(Z)-dienoic acid, and pinellic acid], both of which blocked prostaglandin D₂ production.4
That same year, Lyu and colleagues studied the antiallergic and anti-inflammatory effects of U. davidiana using a 1-fluoro-2,4-dinitrofluorobenzene (DNFB)–induced contact dermatitis mouse model. They found that treatment at a dose of 10 mg/mL successfully prevented skin lesions caused by consistent DNFB application. Further, the researchers observed that topically applied U. davidiana suppressed spongiosis and reduced total serum immunoglobulin and IgG2a levels. Overall, they concluded that the botanical treatment improved contact dermatitis in mice.1
In 2019, So and colleagues studied the chemical components of U. davidiana root bark (isolating a chromane derivative and 22 known substances) and reported data supporting the traditional use of the root bark for gastroenteric and inflammatory indications.3
Bakuchiol [(1E,3S)-3-ethenyl-3,7-dimethyl-1,6-octadien-1-yl]phenol, a prenylated phenolic monoterpene found in the seeds and leaves of various plants, including U. davidiana, is used for its anti-inflammatory properties in traditional Korean medicine.5 Choi and colleagues determined that bakuchiol exhibited robust anti-inflammatory activity in a study of U. davidiana constituents, at least partially accounting for the anti-inflammatory functions of the plant.5
Antifungal activity
In 2021, Alishir and colleagues conducted a phytochemical analysis of the root bark extract of U. davidiana, resulting in the isolation of 10 substances including the novel coumarin glycoside derivative ulmusakidian. Some of the compounds exhibited antifungal activity against Cryptococcus neoformans, though none demonstrated antifungal activity against Candida albicans.6
Wound dressing
Park and colleagues demonstrated in 2020 that superabsorbing hydrogel wound dressings composed of U. davidiana root bark powders, which exhibit gelling activity, performed effectively in speeding up wound closure and cutaneous regeneration in skin-wound mice models. These dressings also displayed thermal stability and superior mechanical properties to pullulan-only gel films. The researchers concluded that gel films composed of U. davidiana have potential to surpass the effectiveness of current products.7
Anti–hair loss activity
Early in 2022, Kwon and colleagues investigated the anti–hair loss mechanism of U. davidiana and determined that supercritical extraction-residues of U. davidiana significantly hinder the secretion of transforming growth factor–beta but dose dependently salvage insulinlike growth factor 1, and substantially decrease dihydrotestosterone synthesis. They concluded that these U. davidiana supercritical fluid extract residues have the potential to halt the loss of human hair.8
Photoprotective potential
Late in 2020, Her and colleagues reported on their development and analysis of a new distillate derived from a fermented mixture of nine anti-inflammatory herbs including U. davidiana. The investigators assessed the effects of the topically applied distillate on UVB-induced skin damage in Institute of Cancer Research mice, finding significant improvements in the dorsal skin photodamage. Application of the distillate also ameliorated collagen production impairment and diminished proinflammatory cytokine levels of tumor necrosis factor (TNF)–alpha and IL-1B. The researchers concluded that this anti-inflammatory herbal distillate, which includes U. davidiana, displays the potential to serve as a photoprotective agent.9
Antiaging activity
In 2011, Yang and colleagues set out to identify constituent substances of the root bark of U. davidiana that have the capacity to suppress cellular senescence in human fibroblasts and human umbilical vein endothelial cells. They isolated 22 compounds, of which epifriedelanol, ssioriside, and catechin-7-O-beta-D-glucopyranoside impeded adriamycin-induced cellular senescence in human dermal fibroblasts and friedelin, epifriedelanol, and catechin-7-O-beta-apiofuranoside in the umbilical vein endothelial cells. Epifriedelanol was the most potent of the substances, leading the researchers to conclude that this U. davidiana component can diminish cellular senescence in human primary cells and has the potential as an oral and/or topical antiaging agent.10
Also that year, in a study on the protective effects of U. davidiana on UVB-irradiated hairless mice, the authors claimed that an ethanol extract of U. davidiana significantly suppressed wrinkle development in mice chronically exposed to UVB.11 This study showed that U. davidiana extract exerts antioxidant activity as evidenced by a decrease in MMP-1 activity. It also demonstrated antielastase activity. The treated mice showed a decrease in wrinkles as compared with water-treated mice.11 Although this is just one study in mice, it may demonstrate a protective effect on elastic fibers on skin exposed to UVB light.
Late in 2020, Lee and colleagues reported on their study of the possible antiaging effects on the skin of (-)-phenolic compounds isolated from the root bark of U. davidiana. The function of collagenase MMP-1 was found to be inhibited by the isolate (-)-catechin, which also halted collagen degradation caused by TNF-alpha in normal human dermal fibroblasts. Further, the investigators demonstrated that the U. davidiana isolate (-)-catechin reduced the expression of proinflammatory cytokines such as IL-1B and IL-6. They concluded that the U. davidiana isolate exhibits the potential to combat intrinsic as well as extrinsic cutaneous aging.12
These findings are particularly intriguing. There is much overlap between intrinsic and extrinsic aging. If U. davidiana can keep collagen intact and inhibit cellular senescence, it may serve as an early intervention toward slowing or preventing skin aging.
Summary
Of greatest interest now, perhaps, is its potential to impede cellular senescence. Senescent cells release a multitude of inflammatory and other factors that hasten intrinsic aging. Blocking cellular senescence is an important approach to the prevention and treatment of skin aging.
Dr. Baumann is a private practice dermatologist, researcher, author, and entrepreneur in Miami. She founded the division of cosmetic dermatology at the University of Miami in 1997. The third edition of her bestselling textbook, “Cosmetic Dermatology,” was published in 2022. Dr. Baumann has received funding for advisory boards and/or clinical research trials from Allergan, Galderma, Johnson & Johnson, and Burt’s Bees. She is the CEO of Skin Type Solutions, a SaaS company used to generate skin care routines in the office and as an ecommerce solution. Write to her at dermnews@mdedge.com.
References
1. Lyu J et al. J Pharmacopuncture. 2013 Jun;16(2):41-5.
2. Eom SY et al. J Cosmet Sci. 2006 Sep-Oct;57(5):355-67.
3. So HM et al. Bioorg Chem. 2019 Oct;91:103145.
4. Choi HG et al. Phytother Res. 2013 Sep;27(9):1376-80.
5. Choi SY et al. J Med Food. 2010 Aug;13(4):1019-23.
6. Alishir A et al. Bioorg Med Chem Lett. 2021 Mar 15;36:127828.
7. Park TH et al. Saudi Pharm J. 2020 Jul;28(7):791-802.
8. Kwon YE et al. Molecules. 2022 Feb 19;27(4):1419.
9. Her Y et al. Molecules. 2020 Dec 29;26(1):124.
10. Yang HH et al. Planta Med. 2011 Mar;77(5):441-9.
11. Kim YO et al. Korean Journal of Medicinal Crop Science. 2011;19(6):508-13.
12. Lee S et al. Antioxidants (Basel). 2020 Oct 13;9(10):981.
Ulmus davidiana, commonly known as yugeunpi, has a long history of use in Korea in treating burns, eczema, frostbite, difficulties in urination, inflammation, and psoriasis,1 and has also been used in China for some of these indications, including skin inflammation.2,3 Currently, there are several areas in which the bioactivity of U. davidiana are under investigation, with numerous potential applications in dermatology. This column focuses briefly on the evidence supporting the traditional uses of the plant and potential new applications.
Anti-inflammatory activity
Eom and colleagues studied the potential of a polysaccharide extract from the root bark of U. davidiana to serve as a suitable cosmetic ingredient for conferring moisturizing, anti-inflammatory, and photoprotective activity. In this 2006 investigation, the composition of the polysaccharide extract was found to be primarily rhamnose, galactose, and glucose. The root extract exhibited a similar humectant moisturizing effect as hyaluronic acid, the researchers reported. The U. davidiana root extract was also found to dose-dependently suppress prostaglandin E2. The inhibition of the release of interleukin-6 and IL-8 was also reported to be significant. The use of the U. davidiana extract also stimulated the recovery of human fibroblasts (two times that of positive control) exposed to UVA irradiation. The researchers suggested that their overall results point to the viability of U. davidiana root extract as a cosmetic agent ingredient to protect skin from UV exposure and the inflammation that follows.2
In 2013, Choi and colleagues found that a methanol extract of the stem and root barks of U. davidiana revealed anti-inflammatory properties, with activity attributed to two trihydroxy acids [then-new trihydroxy fatty acid, 9,12,13-trihydroxyoctadeca-10(Z),15(Z)-dienoic acid, and pinellic acid], both of which blocked prostaglandin D₂ production.4
That same year, Lyu and colleagues studied the antiallergic and anti-inflammatory effects of U. davidiana using a 1-fluoro-2,4-dinitrofluorobenzene (DNFB)–induced contact dermatitis mouse model. They found that treatment at a dose of 10 mg/mL successfully prevented skin lesions caused by consistent DNFB application. Further, the researchers observed that topically applied U. davidiana suppressed spongiosis and reduced total serum immunoglobulin and IgG2a levels. Overall, they concluded that the botanical treatment improved contact dermatitis in mice.1
In 2019, So and colleagues studied the chemical components of U. davidiana root bark (isolating a chromane derivative and 22 known substances) and reported data supporting the traditional use of the root bark for gastroenteric and inflammatory indications.3
Bakuchiol [(1E,3S)-3-ethenyl-3,7-dimethyl-1,6-octadien-1-yl]phenol, a prenylated phenolic monoterpene found in the seeds and leaves of various plants, including U. davidiana, is used for its anti-inflammatory properties in traditional Korean medicine.5 Choi and colleagues determined that bakuchiol exhibited robust anti-inflammatory activity in a study of U. davidiana constituents, at least partially accounting for the anti-inflammatory functions of the plant.5
Antifungal activity
In 2021, Alishir and colleagues conducted a phytochemical analysis of the root bark extract of U. davidiana, resulting in the isolation of 10 substances including the novel coumarin glycoside derivative ulmusakidian. Some of the compounds exhibited antifungal activity against Cryptococcus neoformans, though none demonstrated antifungal activity against Candida albicans.6
Wound dressing
Park and colleagues demonstrated in 2020 that superabsorbing hydrogel wound dressings composed of U. davidiana root bark powders, which exhibit gelling activity, performed effectively in speeding up wound closure and cutaneous regeneration in skin-wound mice models. These dressings also displayed thermal stability and superior mechanical properties to pullulan-only gel films. The researchers concluded that gel films composed of U. davidiana have potential to surpass the effectiveness of current products.7
Anti–hair loss activity
Early in 2022, Kwon and colleagues investigated the anti–hair loss mechanism of U. davidiana and determined that supercritical extraction-residues of U. davidiana significantly hinder the secretion of transforming growth factor–beta but dose dependently salvage insulinlike growth factor 1, and substantially decrease dihydrotestosterone synthesis. They concluded that these U. davidiana supercritical fluid extract residues have the potential to halt the loss of human hair.8
Photoprotective potential
Late in 2020, Her and colleagues reported on their development and analysis of a new distillate derived from a fermented mixture of nine anti-inflammatory herbs including U. davidiana. The investigators assessed the effects of the topically applied distillate on UVB-induced skin damage in Institute of Cancer Research mice, finding significant improvements in the dorsal skin photodamage. Application of the distillate also ameliorated collagen production impairment and diminished proinflammatory cytokine levels of tumor necrosis factor (TNF)–alpha and IL-1B. The researchers concluded that this anti-inflammatory herbal distillate, which includes U. davidiana, displays the potential to serve as a photoprotective agent.9
Antiaging activity
In 2011, Yang and colleagues set out to identify constituent substances of the root bark of U. davidiana that have the capacity to suppress cellular senescence in human fibroblasts and human umbilical vein endothelial cells. They isolated 22 compounds, of which epifriedelanol, ssioriside, and catechin-7-O-beta-D-glucopyranoside impeded adriamycin-induced cellular senescence in human dermal fibroblasts and friedelin, epifriedelanol, and catechin-7-O-beta-apiofuranoside in the umbilical vein endothelial cells. Epifriedelanol was the most potent of the substances, leading the researchers to conclude that this U. davidiana component can diminish cellular senescence in human primary cells and has the potential as an oral and/or topical antiaging agent.10
Also that year, in a study on the protective effects of U. davidiana on UVB-irradiated hairless mice, the authors claimed that an ethanol extract of U. davidiana significantly suppressed wrinkle development in mice chronically exposed to UVB.11 This study showed that U. davidiana extract exerts antioxidant activity as evidenced by a decrease in MMP-1 activity. It also demonstrated antielastase activity. The treated mice showed a decrease in wrinkles as compared with water-treated mice.11 Although this is just one study in mice, it may demonstrate a protective effect on elastic fibers on skin exposed to UVB light.
Late in 2020, Lee and colleagues reported on their study of the possible antiaging effects on the skin of (-)-phenolic compounds isolated from the root bark of U. davidiana. The function of collagenase MMP-1 was found to be inhibited by the isolate (-)-catechin, which also halted collagen degradation caused by TNF-alpha in normal human dermal fibroblasts. Further, the investigators demonstrated that the U. davidiana isolate (-)-catechin reduced the expression of proinflammatory cytokines such as IL-1B and IL-6. They concluded that the U. davidiana isolate exhibits the potential to combat intrinsic as well as extrinsic cutaneous aging.12
These findings are particularly intriguing. There is much overlap between intrinsic and extrinsic aging. If U. davidiana can keep collagen intact and inhibit cellular senescence, it may serve as an early intervention toward slowing or preventing skin aging.
Summary
Of greatest interest now, perhaps, is its potential to impede cellular senescence. Senescent cells release a multitude of inflammatory and other factors that hasten intrinsic aging. Blocking cellular senescence is an important approach to the prevention and treatment of skin aging.
Dr. Baumann is a private practice dermatologist, researcher, author, and entrepreneur in Miami. She founded the division of cosmetic dermatology at the University of Miami in 1997. The third edition of her bestselling textbook, “Cosmetic Dermatology,” was published in 2022. Dr. Baumann has received funding for advisory boards and/or clinical research trials from Allergan, Galderma, Johnson & Johnson, and Burt’s Bees. She is the CEO of Skin Type Solutions, a SaaS company used to generate skin care routines in the office and as an ecommerce solution. Write to her at dermnews@mdedge.com.
References
1. Lyu J et al. J Pharmacopuncture. 2013 Jun;16(2):41-5.
2. Eom SY et al. J Cosmet Sci. 2006 Sep-Oct;57(5):355-67.
3. So HM et al. Bioorg Chem. 2019 Oct;91:103145.
4. Choi HG et al. Phytother Res. 2013 Sep;27(9):1376-80.
5. Choi SY et al. J Med Food. 2010 Aug;13(4):1019-23.
6. Alishir A et al. Bioorg Med Chem Lett. 2021 Mar 15;36:127828.
7. Park TH et al. Saudi Pharm J. 2020 Jul;28(7):791-802.
8. Kwon YE et al. Molecules. 2022 Feb 19;27(4):1419.
9. Her Y et al. Molecules. 2020 Dec 29;26(1):124.
10. Yang HH et al. Planta Med. 2011 Mar;77(5):441-9.
11. Kim YO et al. Korean Journal of Medicinal Crop Science. 2011;19(6):508-13.
12. Lee S et al. Antioxidants (Basel). 2020 Oct 13;9(10):981.