Characterisation an d phytochemical screening of ethanolic extract Citrus reticulata peel and its anti-inflammatory activity using protein denaturation method

Background: Inflammation is an initial systemic response that occurs in the body and necessitates prompt management to prevent complications and death. Natural therapies, including Citrus reticulata, rich in hesperidin, a potent anti-inflammatory flavonoid, are gaining attention due to accessibility and safety. Objective: The aims of this study were to characterise Citrus reticulata peel simplicia and extract to ensure their quality, phytochemical screening and determining its anti-inflammatory activity. Method: Simplicia characterisation involves testing water content, total ash content, and acid-insoluble ash content while the extract is tested for water and total ash content. Phytochemical screening is done using the tube method, and the anti-inflammatory activity test is conducted using the protein denaturation method. Result: The extract had water content and total ash content of 14.91% and 1.89%, respectively. The ethanol extract of Citrus reticulata peel contains flavonoids, alkaloids, saponins, tannins, quinones, steroids, and terpenoids. It shows anti-inflammatory activity with an IC50 value of 132.13 µg/mL, with a difference of approximately 55% to achieve the same level of protein denaturation inhibition as positive control dexamethasone, with an IC50 value of 73.14 µg/mL. Conclusion: Citrus reticulata peel simplicia and ethanol extract met quality standards, contain flavonoids with anti-inflammatory properties, and inhibit inflammation by up to 50% at 132.13 µg/mL.