It has long been used for fertility, to build up testosterone and to stimulate the libido. More often Oyster extract is utilized by men and athletes in order to build their testosterone in a natural way.
When mice earring human colon cancer were fed with oyster extract at the same dose for 15 days, the tumor size reduced to 44. 6% of the control tumors. The possibility that oyster extract inhibits tumor growth by enhancing host immune function, especially killer cell activity, was discussed.
In this study, the oligopeptide-enriched hydrolysates from oyster (Crassostrea gigas) were produced using the protease from Bacillus sp. SM98011 at laboratory level, and scaled up to pilot (100 L) and plant (1,000 L) levels with the same conditions. And the antitumor activity and immunostimulating effects of the oyster hydrolysates in BALB/c mice were investigated.
These results demonstrated that oyster hydrolysates produced strong immunostimulating effects in mice, which might result in its antitumor activity. The antitumor and immunostimulating effects of oyster hydrolysates prepared in this study reveal its potential for tumor therapy and as a dietary supplement with immunostimulatory activity.
A reduced number and/or reduced activity of natural killer (NK) cells, which are important for defense against a variety of cancers and viral infections, occur under various stress conditions and in patients with various diseases. In this article, we report that the 30% to 50% ethanol precipitate of oyster extract (EPOE50) dose-dependently enhanced the activity of mouse spleen NK cells in vitro and in vivo.
Our results indicate that EPOE50 augmented NK cell activity and that its administration to mice inhibited tumor growth presumably through the activation of NK cells and also suggest that the active substance is a sugar-containing oligomer or polymer and is not of bacterial origin.
In this study, the oligopeptide-enriched hydrolysates from oyster (Crassostrea gigas) were produced using the protease from Bacillus sp. SM98011 at laboratory level, and scaled up to pilot (100 L) and plant (1,000 L) levels with the same conditions.
These results demonstrated that oyster hydrolysates produced strong immunostimulating effects in mice, which might result in its antitumor activity. The antitumor and immunostimulating effects of oyster hydrolysates prepared in this study reveal its potential for tumor therapy and as a dietary supplement with immunostimulatory activity.
Reproduction Function - Zinc is a vital nutrient in the normal reproductive function and embryonic development of mammals, and it is well known that oyster extract contains significant amounts of zinc. The effects of oyster extract on reproductive function, such as embryonic development, serum levels of zinc and sperm maturation were examined in zinc‐deficient mice.
From these findings, it is suggested that oyster extract is a useful supplement that can prevent reproductive defects from zinc deficiency, and the bioavailability of zinc may be identical to zinc carbonate.
Aphrodisiac - Totally natural, oyster extract is excellent for men's reproductive health and endurance. It is a rich source for the amino acid taurine, which has a cardio-protective effect and also in nerve transmission. Historically known as an aphrodisiac, flavanoids in oyster meat have been shown to stimulate the reproductive system.
Moreover, oyster peptide SCAP1 had anticancer activity against human colon carcinoma (HT-29) cell lines. Percentage of cell growth inhibition (MTT assay), apoptotic morphological changes (AO/EtBr staining) and oxidative DNA damage (comet assay) were estimated. We thus conclude that the anticancer and antioxidative peptide (SCAP1) from oyster (S. cucullata) may be useful ingredients in pharmaceutical and nutraceutical applications.
Oyster has gained much attention recently for its anticancer activity but it is unclear whether calcium, the major antitumor ingredient in oyster shell, is responsible for the anticarcinogenic role of the oyster. To address this issue, C57BL/6 mice were fed with the carcinogen 4-nitroquinoline-1-oxide (4NQO, 50 µg/mL) and normal diet or a diet containing oyster powder, oyster calcium, or calcium depleted oyster powder.
The results showed that mice on the diet containing oyster calcium significantly reduced rates of tumors in the tongue and proliferation and enhanced differentiation in the oral epithelium compared with the diet containing calcium depleted oyster powder. These results suggest that calcium in oyster plays a critical role in suppressing formation of oral squamous cell carcinoma and proliferation and promoting differentiation of the oral epithelium.
Antioxidant - The focus of the study was to investigate antioxidant activity and characterize antioxidant peptides from oyster (Saccostrea cucullata) protein hydrolysate.
It was found that the hydrolysate did not show any cytotoxic effect for Vero cell lines and exerted a significant cytotoxic effect on HT-29 cell lines. We thus conclude that the anticancer and antioxidative hydrolysate from oyster (S. cucullata) may be useful ingredients in food and nutraceutical applications.
Apoptosis - The antioxidant, and hepatoprotective properties of 3,5-dihydroxy-4-methoxybenzyl alcohol (DHMBA), a natural phenolic antioxidant isolated from the Pacific oyster, were defined using cultured human hepatocyte-derived cells (C3A).
DHMBA is a novel, potent antioxidant, effectively protecting cultured hepatocytes from apoptosis and necrosis caused by oxidative stress.