A study published earlier this month in the scientific journal Cosmetics by researchers from Thailand has concluded that extracts from the Dendrobium sulcatum Lindl Orchid plant are “a promising source of natural active ingredients for anti-skin-aging.” Researchers examined “the biological activities, including antioxidation, anti-lipid peroxidation, antiglycation, anti-inflammatory and anti-tyrosinase properties of ethanolic extract of D. sulcatum stems, leaves and flowers, which were successfully elucidated and revealed for the first time.”
Study background and goals
Thailand is one of the largest Orchid growing areas globally. As detailed in the study, Dendrobium species specifically have been used historically in Chinese folk medicine for their anti-inflammatory properties, and recently, “cosmetic and cosmeceutical applications of the Orchidaceae family and some Dendrobium species have been reported to be potentially active in lowering melanin production, antioxidation, anti-aging with MMP2 inhibitory effect and tyrosinase inhibition. However, until researchers conducted this study, the potential benefits of Dendrobium sulcatum in topical cosmetic applications remained unexplored.
The research team sought to first derive and determine the phytochemical makeup of Dendrobium sulcatum extracts before investigating the potential anti-aging benefits, including the extract’s possible antioxidant, antiglycation, anti-inflammatory, and anti-tyrosinase properties. To begin the study, researchers harvested a whole plant specimen from Muang, Nan Province, Thailand. They first separated the stem, leaves, and flowers then cleaned and dried each. The plant matter was then ground into a fine powder, extracted with ethanol, and filtered into a crude extract for testing and analysis.
Testing flavonoid and phenolic content
“The flavonoid and phenolic compounds are known as plant secondary metabolites for antioxidation, anti-inflammation, etc., which might be related to the traditional use of this plant as a health tonic and anti-aging treatment,” researchers reported. “Therefore, the content of flavonoids and phenols was characterized in this study.”
Testing to examine total phenolic and flavonoid contents were performed first, utilizing gallic acid and quercetin, respectively. The results of phenolic contents determined that “the stem and leaf extracts had a higher content of total phenolic contents than the flower extract, which indicated that all ethanolic extracts of D. sulcatum contain phenolic compounds.”
Flavonoid content testing also utilized the ethanolic extract of the stems, leaves, and flowers of D. sulcatum, and “results showed that the highest value of total flavonoid content was obtained from the leaf extract followed by the flower and stem extracts.” Results revealed that the “flavonoid constituents found in Dendrobium species were flavone C-glycosides and flavonols.”
Determining antioxidant and anti-inflammatory potential
Following these assessments, “the three different parts of D. sulcatum, namely stem, leaf and flower extracts were investigated for antioxidant properties using DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP) and ABTS radical scavenging assays.”
The primary antioxidant screening utilized DPPH free radical scavenging assay, and “among the test samples, the one exhibiting the highest antioxidant effect was the leaf extract, which was about 1.5 and 3 times higher than stem and flower extracts, respectively. These results suggest that the ethanolic extract of D. sulcatum leaves has greater potential for DPPH free radical scavenging than the other parts.”
Additional testing utilizing the FRAP and ABTS radical scavenging assays confirmed “higher antioxidant activities in the ethanolic extracts of the leaves and stems than in those of the flower extracts, and that the leaf extract tends to be more active in antioxidation than extracts of other parts.”
Based on the results of the extensive testing performed, researchers concluded that there is strong scientific evidence supporting Dendrobium sulcatum’s efficacy as an anti-inflammatory, anti-aging bioactive ingredient in topical cosmetic products. Test results indicate that extracts from the stems and leaves show more significant potential benefits than the Orchid plant’s flowers.
Researchers also noted that “the limitation of this study is that the major chemical constituents associated with the biological activities of D. sulcatum extracts are not known,” as this study was the first of its kind. Therefore, “further studies to identify the biomarkers, evaluate the cytotoxicity of human cells, and perform quality control and pre-formulation study of the plant extracts would be essential for further application of the extracts in cosmetic and cosmeceutical products.”
2023; 10(2):43. https://doi.org/10.3390/cosmetics10020043
"Assessment of Antioxidant, Anti-Lipid Peroxidation, Antiglycation, Anti-Inflammatory and Anti-Tyrosinase Properties of Dendrobium sulcatum Lindl"
Authors: Rungsang T., et al