Effect of red edible seaweed Eucheuma denticulatum on diet-induced obesity in vivo

Eucheuma denticulatum is a red edible seaweed found in the east coast of Malaysia. This seaweed has shown to promote potential health benefits. The present work aimed to assess the anti-obesity effect of E. denticulatum freeze-dried powder supplemented with high-fat diet (HFD) on an in vivo model. Male Sprague Dawley rats aged 6-7 weeks (weighing 200-250 g) were divided into six groups (n = 6 per group) according to the following diet: normal diet group (CTR), high-fat diet group (HFD), HFD with orlistat (50 mg kg(-1)) (HFD + OR), HFD with 10% E. denticulatum (HFD-10), HFD with 15% E. denticulatum (HFD-15), and HFD with 20% E. denticulatum (HFD-20). Each group was fed for 7 weeks ad libitum, and food intake was monitored. At the end of the nutritional period, the rats were sacrificed. Blood was collected for determination of biochemical parameters and obesity biomarkers while tissue samples for histological analysis. Acute oral toxicity was employed to assess E. denticulatum for possible toxicity. Eucheuma denticulatum-fed rats significantly (p < 0.05) reduced weight gain, BMI, Lee index, visceral fat mass, triglyceride, liver enzymes, insulin, and leptin while improving ghrelin level relative to the HFD-fed rat. Food and energy intakes did not differ between the HFD and treatment groups. Histopathological examination showed E. denticulatum supplementation decreased fat size and reduced lipid droplets in the liver. Moreover, E. denticulatum showed no sign of toxicity in rodent acute oral toxicity study. Eucheuma denticulatum effectively attenuates weight gain independent of food intake and improving its related biomarkers, highlighting the potential of E. denticulatum in tackling obesity associated pathologies.