Study On Trophic Value And Antioxidant Activity Of Alcohol Soluble Substances From Abalone Viscera

Abalone viscera is rich in nutrition. In recent years many scholars have committed to thedeep processing of abalone viscera and their active substances, especially studying on someactive substances as polysaccharides extracted from abalone viscera. In the pilot scale extractionprocess of polysaccharides from abalone viscera （Haliotis discus hannai Ino）, significantamounts of the supernatant of the ethanol by-product was produced after the ethanolprecipitation. In this paper, in order to reduce enviro nmental pollution and improveresource utilization, ethanol was reclaimed from the supernatant of the ethanol, then thesupernatant was concentrated under reduced pressure and freezed drying to obtain abaloneviscera alcohol soluble substances （termed as AVASS）. The trophic value of AVASS wasanalyzed through measurement of its nutrition constituent and amino acids evaluation.A relatively full evaluation method including chemical models in vitro, cellular models andanimal models in vivo was used to evaluate its antioxidant activities. Abalone viscera alcoholsoluble substances provided a reference in the development of abalone viscera antioxidant drugs,cosmetics and functional food. The conclusions were as follows:（1）The content of protein, polysaccharides, crude fat, moisture and ash in AVASS was47.00%、33.23%、6.37%、8.69%、3.02%respectively. The result indicated that except Trp、Gln、Asn, other17kinds of amino acids were detected in AVASS, which included Phe, Lys, Leu, Ile, Met, Valand Thr seven essential amino acids for humans, the content of essential amino acids was37.43%of the total amino acids. It had nine essential amino acids for children （His and Arg wereessential amino acids for children）, which occupied41.60%of total amino acids content. Flavoramino acids content was45.91%, branched-chain amino acids content was20.00%, and theantioxidant activity of amino acids content was30.00%. RC value of AVASS’s amino acids wasdispersed and the SRC value was37.46. It explained that the essential amino acids of AVASShad greatly negative effect on amino acid balance, and the SRC value was small. The firstlimiting amino acid was Trp, followed by Met and Cys. In short, AVASS was a raw material forfood, with high protein, low fat and good potential to develop into a seasoning and antioxidantfood. （2） The result of chemical models experiment showed that AVASS had strong antioxidantactivity in vitro. With the concentration of the AVASS increasing, abilities of scavenginghydroxyl radical and superoxide radical as well as the total reducing power were increasing,showing a clear dose-effect relationship within a certain range. With the Vc concentration of40μg/mL as the reference, the OD value at700nm was0.420.4mg/mL AVASS’s OD value was0.497and the reducing power was stronger than that in Vc. When the AVASS concentration was10mg/mL, its OD value was0.781and the reducing power was greatly stronger. Thesemi-inhibitory concentrations of AVASS to scavenge O2-· and·OH radical were10.6mg/mL and11.9mg/mL respectively, the regression equations were y=0.040x+0.074with R value0.992andthe square of R0.984, as well as y=0.041x+0.012with R value0.986, the square of R0.973.（3）The antioxidant activity of AVASS was detected by cellular models. AVASS could improvecell viability and SOD activity of injured HepG2cells induced by H₂O₂, and decrease the contentof MDA. It was found that AVASS had protective effect on the hydrogenperoxide-induced injury in HepG2cells by inhibiting oxidative injury. Compared with normalcontrol group, the cell viability and SOD activity significantly decreased in the H₂O₂injurygroup （P<0.01）, the MDA content was significantly higher in the H₂O₂injury group （P<0.01）.With the concentration of AVASS and Vc increasing, the cell viability and SOD activity rose andthe content of MDA dropped. When HepG2cells were given the AVASS concentration of80or100μg/mL, the cell viability was significantly higher （P<0.01）, SOD activity was significantlystronger （P<0.05）, and the MDA content was extremely lower （P<0.01） compared with those inthe H₂O₂injury group. And in high concentration group （100μg/mL）, the three indexes wereclosed to or higher than those in the normal group.（4） Vivo experiments of aging model mice induced by D-galactose proved that, the mice whowere gavaged AVASS delayed senile and were stronger than model group’s mice. Incapable anderect hairs phenomenon was also slighter. A certain dose of AVASS could improve theantioxidant enzymes （SOD） activity and GSH content and reduce the high level of lipidperoxidation product MDA which was produced by “oxidative stress”, in blood and liver of theaging mice induced by D-Gal. Experiments also showed that AVASS had good antioxidanteffects by reducing cell membrane lipid peroxidation and keeping the oxidation-antioxidant equilibrium state in the organism. The capability of retarding aging came to the highest point inthe group with800mg·kg^-1·d^-1AVASS. They hadn’t displayed incapable and erect hairsphenomenon, and their weights were closed to the level of normal group and Vc group. The levelof MDA and SOD activity and the content of GSH approached those of the Vc group. Itindicated that the antioxidant activity of AVASS in the dose of800mg·kg^-1·d^-1was equal to thatof Vc in10mg·kg^-1·d^-1.