TY - JOUR AU - WINITCHA, SUPANIDA AU - LIENGPRAYOON, SIRILUCK AU - SUPHAMITMONGKOL, WARAWUT AU - TOMORN, NADDAMAS AU - CHAIYUT, JATUPORN AU - LERKSAMRAN, TUKSIN AU - BANCHONG, YUTTHANA AU - TRISONTHI, PIYAPAT AU - SAAH, SAFIAH AU - MUSIGAMART, NATEDAO PY - 2021/12/31 Y2 - 2024/03/29 TI - PHYTOCHEMICAL COMPOSITION AND BIOLOGICAL ACTIVITIES OF CRUDE EXTRACT FROM FLOWERS AND LEAVES OF Rhododendron arboreum Sm. FROM NORTHERN THAILAND JF - Malaysian Applied Biology JA - MAB VL - 50 IS - 3 SE - Research Articles DO - 10.55230/mabjournal.v50i3.2211 UR - https://jms.mabjournal.com/index.php/mab/article/view/2211 SP - 23-37 AB - <p><em> <span class="fontstyle0">Rhododendron arboreum </span></em><span class="fontstyle2">Sm. has wide applications in food and beverage, medicines, and cosmetics because the plant contains bioactive phytochemical components. In Thailand, other than for horticultural purposes, scant literature describes the potential applications of this </span><em><span class="fontstyle0">Rhododendron </span></em><span class="fontstyle2">species. Phytochemical composition, biological activity, and cell cytotoxicity of </span><em><span class="fontstyle0">R. arboreum </span></em><span class="fontstyle2">Sm. flower petal and leaf extracts were determined. Ethanolic extracts of fresh and dried flower petals (FF and DF, respectively) and dried leaves (DL) of </span><em><span class="fontstyle0">R. arboreum </span></em><span class="fontstyle2">were prepared by maceration with 60% ethanol for 7 days. Extraction yields of both FF and DF were higher than DL (19.22, 16.76, and 8.50% for FF, DF, and DL, respectively). Preliminary qualitative phytochemical screening showed different compositions in diverse plant parts. Saponins and tannins were present in every extract, with anthraquinones detected only in flowers and terpenoids only in leaves. Total phenolic (TPC) and flavonoid contents (TFC) were highest in DL (405.21 mg gallic acid equivalent and 127.30 mg catechin equivalent per g of dry extract, respectively), followed by DF and FF. Antioxidant properties were determined using two radical scavenging assays as 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azinobis(3-ethyl-benzthiazoline-6-sulfonic acid (ABTS). Results indicated that all extracts exhibited better inhibitory activity against DPPH radical than ABTS radical as evidenced by lower IC</span><span class="fontstyle2">50 </span><span class="fontstyle2">range 24.65-48.15 ìg/mL for DPPH and 65.19-76.36 ìg/mL for ABTS, respectively. A positive correlation coefficient between the two antioxidant assays and TPC and TFC of </span><em><span class="fontstyle0">Rhododendron </span></em><span class="fontstyle2">extracts indicated antioxidant potential distributed in both components. No cytotoxicity was recorded in the three extracts, with concentrations less than 500 μg/mL for both 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) and CellTiter-Blue</span><span class="fontstyle2">® </span><span class="fontstyle2">assay. </span><span class="fontstyle0">In vitro </span><span class="fontstyle2">studies<br />exhibited dose-dependent and strong anti-melanogenic and anti-inflammatory activities ranging from 50 to 250 μg/mL for FF, DF, and DL. Results identified various bioactive constituents with potential biological activity (antioxidant, antiinflammatory, and anti-melanogenic), while non-cytotoxicity in </span><em><span class="fontstyle0">R. arboreum </span></em><span class="fontstyle2">flower and leaf extracts suggested the possibility of further applications as a functional ingredient in cosmetics.</span></p> ER -