Assessment of Wound Healing Properties of Medicinal Plants: The Case of <i>Berlinia confusa</i>

Objectives Berlinia confusa is used as wound healing agent in folklore medicine. However, this has not been scientifically validated and there is dearth of information on its bioactive metabolites. The current research aimed at evaluating the wound healing, antioxidant and antimicrobial activities of the stem bark of the plant and track down some of its metabolites. Methods The dermal excision model in Sprague Dawley rats was used for the in vivo wound healing activity of the 70% ethanol extract (formulated as 1% and 2% cream). The DPPH radical scavenging and in-vivo lipid peroxidation assays were used to assess the antioxidant activity whereas the agar well and broth-dilution assays were used for the antimicrobial activity evaluation. The PrestoBlue cell viability in keratinocytes and acute dermal toxicity assays were used for the safety assessment. Results The 1% w / w extract showed over 70% wound surface closure from day 13-23 whereas the 2% w / w exhibited similar effect from day 15-23. The activity of the extract was comparable to 1% silver sulphadiazine (SSD) used as reference agent. The extract (1% w / w ) also significantly reduced malondialdehyde (MDA) levels (455.2 ± 11.91) compared to the negative control group (739.8 ± 44.93) and was also superior to silver sulphadiazine (MDA level 548.4 ± 10.73). The extract again showed a considerable antimicrobial activity against pathogenic microorganisms with MIC's in the range of 5-10 mg/mL. The 2% extract did not show any skin irritation and were mildly toxic (88.2 ± 3.76% viability) to keratinocytes. Purification of the extract yielded two (2) major known wound healing metabolites including betulinic acid and catechin. Conclusion Berlinia confusa has demonstrated considerable wound healing in vivo and also mitigated healing modifying factors such as microbes and reactive oxygen species.