Principal component analysis (PCA) of bioactive compounds and antioxidant activity of various sample particle sizes of sea urchin shells from coastal area of Lombok Island

The most common technique in increasing pharmacological activity is by reducing sample particle size. This study aims to investigate the impact of different particle sizes on the bioactive composition and antioxidant activity of sea urchin shells collected from the coastal areas of Lombok Island. Sea urchin shell powders ranging in particle sizes <45 µm, >45 µm, <125 µm, >250 µm, and >2000 µm were extracted using 70% ethanol via the cold maceration method. The composition of bioactive compounds was analyzed using GC-MS, while antioxidant activity was evaluated using the DPPH free radical scavenging assay. Principal Component Analysis (PCA), conducted using Minitab software, was employed to summarize the interrelationships among all variables in the study. The findings reveal that each particle size exhibits a distinct composition of bioactive compounds. The highest concentrations of bioactive compounds and the greatest antioxidant activity were observed in samples with particle sizes >45 µm. PCA identified several bioactive compounds, such as lanolin, palmitic acid, myristic acid, stearic acid, heptadecene-(8)-carboxylic acid, 5,8,11,14-eicosatetraenoic acid, and 9-hexadecanoic acid, contributing significantly to this antioxidant effect. Reducing the particle size was found to alter the composition of bioactive compounds and enhance antioxidant activity. These bioactive compounds show promise for further exploration in the development of new drugs derived from marine sources.