Extraction of fucoxanthin from selected Malaysian brown seaweeds and its effects on 3T3-L1 adipocyte cells

Abstract

Obesity (BMI >30 kg/m2) is becoming a major public problem as it affects over 400 million of the population. Despite advances in the development of more effective weight loss drugs, safety and dependence remains an issue. This study aims to establish the antiobesity potential of Malaysian brown seaweeds Sargassum oligocystum, Padina australis and Dictytota dichotoma. Fucoxanthin has been described as the main bioactive compound in brown seaweed exerting antiobesity effect. Three extraction parameters were optimized in order to retain maximum fucoxanthin content in the extract: solvent, particle size and method of extraction. Optimal solvent and particle size for extraction across all seaweeds was acetone and particles sieved through 500?m mechanical sieve. S. oligocystum and P. australis were best extracted using Soxhlet procedures, while D. dichotoma was best extracted using maceration. The fucoxanthin content was analyzed using HPLC equipment. The highest amount of fucoxanthin present in the seaweeds was found in Sargassum oligocystum (754.8 mg/g dry weight), followed by D. dichotoma (142.9 mg/g) and finally P. australis extracts (91.58 mg/g). The extract showing best antiadipogenic effect on the preadipocytes was SAE (lipid accumulation equivalent to 0.170 ± 0.034 A), followed by DAE (0.196 ± 0.082 A) and finally PAE (0.203 ± 0.047 A). SAE had the best proadipolytic effect on mature lipid cells (31.86 ± 17.56 mg/ml glycerol release), followed by PAE (30.54 ± 15.41 mg/ml) and finally DAE (28.12 ± 11.36 mg/ml). Statistical analysis using one- way ANOVA indicated that the differences were not significant (p>0.05). Overall, antiobesity activity levels did not coincide with fucoxanthin levels present in the extract, indicating the presence of various compounds in the extract that exert diverse effects on 3T3-L1 adipocytes. The study describes fucoxanthin content of the Malaysian seaweeds and its optimal extraction parameters. Furthermore, it indicates the adipogenic and adipolytic potential of the extracts as antiobesity agents and the potential for seaweed extracts to be further developed as a safe and effective natural alternative for the management of obesity.