Antioxdant, antimicrobial and wound healing properties of quercus infectoria gall extracts

Abstract

Quercus infectoria is one of the greatest herbs and contains several bioactive compounds which are believed to possess wound healing property. However, the scientific data to support its wound healing action is very rare and to date, the extraction of local Q. infectoria using various solvents is not well-established. Hence, the objective of the present research is to evaluate the antioxidant, antimicrobial and wound healing properties of Q. infectoria extract using relevant in vitro assay for application in topical wound management. Q. infectoria were extracted by using four solvents, namely 100% water, 99.8% and 70% methanol, 70% ethanol, 99.8% acetone and 99.8% ethanol. The extracts were then subjected to high performance liquid chromatography (HPLC) to identify the presence of gallic acid and tannic acid, while the total phenolics content were measured using Folin-Ciocalteu method. The extracts were tested using appropriate in vitro models, which were antioxidant (DPPH assay), antimicrobial (disc diffusion assay), suitable dose study (MTT assay), and fibroblast migration to the wounded area (scratch assay). Antimicrobial activity was tested against common bacteria found in wounds, which were Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis and Staphylococcus aureus. In HPLC analysis, gallic acid and tannic acid were found in all extracts in the range concentration of 34.04 until 2975.11 mg/g which might be the responsible compounds for wound healing activity. Water extract showed the highest antioxidant activity of approximately 94.55% ± 0.59, while acetone extract showed the largest inhibition zone for disc diffusion assay (19.00 ± 0.14 mm). All extracts were found to stimulate the growth of the fibroblast at 1 μg/ml-0.001 μg/ml, induced the migration rate up to 77% ± 3.05, and statistically significant when compared with control (p<0.05). These findings supported the traditional claim of Q. infectoria for its potential in wound healing activity and it can be a good herbal to incorporate in the topical wound healing product.