Exploring Melanin Expression Through Immunohistochemistry in Skin Grafts After Robusta Coffee Bp-42 Extract Gel Administration: A Novel Approach to Understanding Pigmentation and Regeneration

Abstract

This study examines the efficacy of kojic acid and Robusta BP-42 coffee bean extract in reducing skin hyperpigmentation in rats with skin grafts. Kojic acid is a commonly used compound for pigmentation reduction; however, it can cause adverse effects like skin irritation, redness, and itching in some patients. Robusta BP-42 is a superior variety of robusta coffee found in Indonesia, specifically provided by the Indonesian Coffee and Cocoa Research Institute in Jember Regency, East Java. BP-42 coffee beans are distinguished by their exceptional quality and sensory attributes compared to other strains. The experiment involved three groups of rats with grafted skin: one group was treated with a 2% kojic acid gel (positive control), another with a 5% robusta BP-42 coffee extract gel, and the third with a placebo gel (negative control). The grafted skin was observed and photographed on days 0, 4, 7, 11, 18, and 21, with skin pigmentation measurements conducted using Image J software. Histological analysis was performed on days 7, 14, and 21 for all treatment groups.These preparations were stained immunohistochemically with anti-tyrosinase antibody (T311). The results of the immunohistochemical examination in the negative control group showed the presence of melanocyte cell anti-tyrosinase antibody expression that was immunopositive on days 7, 14, and 21. Meanwhile, the positive control and treatment groups showed the same results, decreasing melanocyte cell anti-tyrosinase antibody expression from immunopositive to immunonegative starting on day 14. This research proves that the gel of robusta coffee extract administration decreases melanin production in skin graft wound healing. So robusta coffee extract gel can be an alternative to prevent the process of increasing pigmentation after skin grafting.