Lipid‐Lowering and LDL‐Oxidation Inhibitory Effects of Aqueous Extract of Freshwater Clam (Corbicula fluminea)—Using Tilapia As an Animal Model

Abstract

A previous study has demonstrated that tilapia able to exhibit hyperlipidemia and hypercholesterolemia is a good model for the evaluation of beneficial effects of nutraceuticals. In this study, tilapia were used to evaluate the in vitro and in vivo effects of a hot water extract (FC-HW) of freshwater clam (Corbicula fluminea). FC-HW prolonged the lag phase of Cu(2+)-induced human and tilapia LDL oxidation. The prolongation of the lag phase was concentration-dependent in human (r(2)= 0.94) and tilapia LDL (r(2)= 0.98). The antioxidative potential of FC-HW was 0.33% (on a weight basis) of Trolox, a positive control. Male tilapia (n= 24) were randomly divided into 2 groups and separately fed for 60 d with an isocaloric also isoprotein diet containing 2% (w/w) FC-HW or a control diet. Body length and body mass were significantly higher in fish fed FC-HW than those of the control group (P < 0.05). Total triacylglycerol, cholesterol, and LDL-C in plasma of the FC-HW group were significantly lower (-89.9%, -61.8%, and -54.5%, respectively), while plasma total antioxidant capacity of the FC-HW group was higher and the lag phase in Cu(2+)-induced LDL oxidation was longer than those of the control group (P < 0.05). FC-HW demonstrated hypolipidemia and hypocholesterolemia effects and inhibited human LDL oxidation in vitro and tilapia LDL both in vitro and ex vivo, indicative that FC-HW can be a potential nutraceutical to reduce the risk factors of atherosclerosis.

Hypocholesterolemic effect of compounded freshwater clam protein hydrolysate and Gracilaria

“…Clams are not only a source of protein, but also have hypocholesterolemic activities, which have been confirmed in freshwater clam (Corbicula fluminea) extract (Chen, Lin, Shiao, & Pan, 2008;Chijimatsu, Tatsuguchi, Abe, Oda, & Mochizuki, 2008), seaweed polysaccharides, and a seaweed mixture including brown and red seaweeds (Suzuki, Ohsugi, Yoshie, Shirai, & Hirano, 1996;Wang, Onnagawa, Yoshie, & Suzuki, 2001). The hypocholesterolemic activity of clam hydrolysates and the dietary fibres of seaweeds have contributed to the suppression of both cholesterol adsorption and cholesterol micellar solubility, in addition to inhibition of ileal re-adsorption of bile acids (Gallaher, Hassel, & Lee, 1993;Zhong, Liu, Ma, & Shoemaker, 2007).…”

“…The hydrolysate shows inhibitory effects on angiotensin I-converting enzyme (ACE) with an IC 50 value of 0.043 mg/ml (Tsai, Lin, Chen, & Pan, 2006). Additional studies showed that the hot water extract of freshwater clam meat has hypocholesterolemic effects on rats (Chijimatsu et al, 2008) and in tilapia, a surrogate animal model (Chen et al, 2008).…”

Nutraceutical Quality of Shellfish

“…35.1). The LDL oxidation rate in the propagation phase and the maximal oxidative state are reduced by the dietary intake of the clam extract [30].…”

“…Total cholesterol, triacylglycerols (TAG), and LDL cholesterol were reduced in the plasma of tilapia fed feed fortified with dried hot-water extract of freshwater clam (Table 35.1) [30], which is effective in cholesterol and lipid regulation.…”

Bacteriostatic Effect of a Calcined Waste Clamshell-Activated Plastic Film for Food Packaging

“…The freshwater clam, Corbicula fluminea, has been successfully cultured in Taiwan and the hot-water extraction of clams has been commercialized for health products [1], domestic consumption, and export to other Asian countries. Small portions of the clamshell are used as food additive and the large remainder is considered commercial waste.…”