Optimal Extraction Process and In Vivo Anti-Inflammatory Evaluation of High Purity Oily Capsicum Oleoresin for Pharmaceutical Applications

Recently, plant-derived anti-inflammatory products have received an increasing attention from researchers due to their excellent in vivo activity with limited side effects. Therefore, the extraction of natural active compounds from the plant with high purity for use in anti-inflammatory formulations is required. In this study, oily Capsicum oleoresin (OCO) was extracted from Capsicum frutescens L. in ethanol by the ultrasound-assisted extraction technique, followed by a centrifugation step for a high purity OCO extract, which can be applied to develop anti-inflammatory formulations. The impact of various conditions (ethanol concentration, sonicating temperature, extraction time, solvent-to-sample ratio, and extraction repetition) on the efficiency of the extraction process was investigated. The results showed that the optimized conditions for the high yield of OCO were 95% ethanol, 50–60°C, 60 minutes, solvent-to-sample ratio of 5 : 1 ml/g, and one extraction repetition, followed by centrifuging at 5000 rpm in 2 hours. Then, the purity and in vivo anti-inflammatory activities of the obtained OCO was then determined by using the HPLC method and carrageenan-induced mice paw edema model, respectively. The purity of OCO was determined as 3.408 mg capsaicin per gram of Capsicum powder; meanwhile, its anti-inflammatory effect value was approximate to that of the commercial drug diclofenac after 48 hours of treatment. The high purity OCO prepared by this low-cost and ecofriendly extraction process would be a promising material for anti-inflammatory formulations.