Ethnomedicinal Knowledge Verification for the Antidiarrheal and Antioxidant Effects of Rhus chinensis Mill. Fruits with Identification of Thirty Constituents

Abstract

Background: Ethnobotanical survey in the rural villages in Nepal revealed that the fruits of Rhus chinensis Mill. have been using for the treatment of diarrhea and dysentery. Objective: To evaluate antimicrobial and antioxidant effects, and identification of chemical constituents in the fruits of R. chinensis. Materials and Methods: Phytochemical screening was performed on the hexane and 70% methanolic extracts of the sample followed by gas chromatographymass spectrometry (GC-MS). Total phenolic content (TPC) was estimated using Folin-Ciocalteu method. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radical and hydrogen peroxide scavenging assays were used to evaluate the antioxidant capacity. Antibacterial effect was estabilished by the Agar well diffusion assay. Results: A total of 30 compounds belonging to phenolics, anhydrides, aldehydes, fatty acids and hydrocarbons were identified in the extracts. The TPC value of 123.52±1.29 mg GAE/g dry extract was estimated. IC 50 value of 135.54±0.82 µg/mL was calculated in DPPH free radical scavenging assay. Scavenging of 42.69±0.1% DPPH free radical and 63.20±1.48% hydrogen peroxide at 100 µg/mL concentration of 70% methanolic extract were estimated. The maximum zone of inhibition (ZOI) observed was 23.00±0.57 mm against Escherichia coli at loading dose of 5 mg of the extract. Conclusion: All together 30 compounds were identified in the fruits. The extracts efficiently inhibited the growth of E. coli and Shigella dysenteriae verifying the rural knowledge. At the same time, the extracts displayed efficient antioxidant activity. The phytochemicals identified were responsible for these activities.

Preparation of 3‐pentadecylphenol‐modified cellulose nanocrystal and its application as a filler to polypropylene nanocomposites having improved antibacterial and mechanical properties

“…Others have reported that CNC has small antibacterial activity or non‐antibacterial property 44,91–95 . The larger antibacterial activity value of f‐CNC can be ascribed to the PDP moiety attached on CNC 43 because PDP is expected to have the antibacterial property from the studies by us and others 31–33,38–41 . It is well known that antibacterial moiety attached on the polymers and other substrates can improve the antibacterial property of them 38,96,97 .…”

“…We further found that the antibacterial property of cardanol could be maintained after the UV irradiation that transforms the unsaturated alkyl groups to saturated ones 31,33,38 . In addition, Aegle marmelos (L.) Correa, Rhus chinensis , and Schlechtendalia chinensis containing PDP as one of their components have the antibacterial property 39–41 . Therefore, we used PDP having long alkyl group in this work to functionalize CNC to make a filler system having the antibacterial property and the compatibility with PP.…”

“…31,33,38 In addition, Aegle marmelos (L.) Correa, Rhus chinensis, and Schlechtendalia chinensis containing PDP as one of their components have the antibacterial property. [39][40][41] Therefore, we used PDP having long alkyl group in this work to functionalize CNC to make a filler system having the antibacterial property and the compatibility with PP.…”

“…For example, inorganic particles including copper, 83 silver, [84][85][86] titanium oxide, 87 and zinc oxide 88 have been used as the antibacterial fillers although the deterioration of mechanical properties 84 and the elution of toxic particles 89 are known as the disadvantages. Since the antibacterial activity of CNC 90,91 and PDP [39][40][41] had been reported before, the antibacterial property of PP/CNC and/or PP/f-CNC was expected.…”

“…44,[91][92][93][94][95] The larger antibacterial activity value of f-CNC can be ascribed to the PDP moiety attached on CNC 43 because PDP is expected to have the antibacterial property from the studies by us and others. [31][32][33][38][39][40][41] It is well known that antibacterial moiety attached on the polymers and other substrates can improve the antibacterial property of them. 38,96,97 Therefore, the antibacterial property of CNC that had been ascribed to its intrinsically stiff structure was further improved by the attachment of PDP having the antibacterial property.…”