Abstract
Centella asiatica has been included in Thai traditional medicinal plants and recipes, as a well-established historical use as a vegetable and tonic. However, when applied in modern formulations, the progressive degradation of the plant pigments occurs, causing color-fading and color variation in the products. Depigmentation of the comminuted sample using supercritical carbon dioxide (scCO2) fluid extraction with a cosolvent was introduced as a pretreatment to solve the color-fading problem. The contents of compounds with known biological activities and the wound healing activities (antioxidant screening by DPPH and ABTS+ scavenging activities; cell migration assay; matrix metallopeptidase [MMP]-2 inhibition on human skin fibroblast; endothelial cell tube formation assay) of the C. asiatica leaf extracts obtained by conventional ethanolic extraction (CV) and pretreatment using scCO2 extraction, were determined. Total triterpenoids (madecassoside, asiaticoside B, asiaticoside, madecassic acid, terminolic acid and asiatic acid) and total triterpenoid glucosides (madecassoside, asiaticoside B and asiaticoside) were notably more abundant in the extract that had been pretreated using scCO2 than the extract obtained by CV. Moreover, the scCO2 pretreatment not only caused greater relative MMP-2 inhibition (58.48 ± 7.50% of the control), but also exhibited a higher cell migration (59.83 ± 1.85% of the initial) and number of vessels (18.25 ± 4.58) of angiogenesis in the wound healing process. Additionally, positive correlations were observed between the DPPH antioxidant activity and madecassoside content (r = 0.914, p < 0.01), as well as between the cell migration activity and asiaticoside content (r = 0.854, p < 0.05). It can be concluded that the scCO2 pretreatment of C. asiatica can eliminate color pigments from the extract and improve its in vitro wound healing activity.
Highlights
Wound healing is critical in maintaining the physical barrier function of the skin
Cell migration occurs to protect against environmental pathogens, and local hemorrhaging is stopped by coagulation factors
We introduced scCO2 with the cosolvent to extract the pigments from C. asiatica, and thereby eliminate the dark green appearance of the extract before ethanolic maceration
Summary
Wound healing is critical in maintaining the physical barrier function of the skin. It plays a pivotal role to protect the body from pathogens when the skin is damaged. Processes 2020, 8, 277 process involves three overlapping stages: inflammation, proliferation and remodeling [1]. Cell migration occurs to protect against environmental pathogens, and local hemorrhaging is stopped by coagulation factors. In the second or proliferation stage, cells contract to close the wound, and angiogenesis is initiated, forming new blood vessels to deliver nutrients, fluid and oxygen to the cells in the wound area. The remodeling stage is the last recovery process. The stimulation of collagen fiber production in the cells is required to remodel the tissue for full recovery [2]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
