Metabolomics and Proteomics Responses of Largemouth Bass (Micropterus salmoides) Muscle under Organic Selenium Temporary Rearing.

Organic selenium has been widely studied as a nutritional supplement for animal feed. However, there are few studies on the effect of organic selenium on flesh quality. In this study, the effects of organic selenium (yeast selenium (YS), Se 0.002 mg/L) on the metabolism and protein expression in Micropterus salmoides muscle under temporary fasting condition (6 weeks) were investigated. The muscle structure was observed through a microscope, and regulatory pathways were analyzed using proteomics and metabolomics methods. Electron microscopy showed that YS made the muscle fibers of M. salmoides more closely aligned. Differential analysis identified 523 lipid molecules and 268 proteins. The numbers of upregulated and downregulated proteins were 178 and 90, respectively, including metabolism (46.15%), cytoskeleton (11.24%) and immune oxidative stress (9.47%), etc. Integrated analyses revealed that YS enhanced muscle glycolysis, the tricarboxylic acid cycle and oxidative phosphorylation metabolism. In the YS group, the content of eicosapentaenoic acid was increased, and that of docosahexaenoic acid was decreased. YS slowed down protein degradation by downregulating ubiquitin and ubiquitin ligase expression. These results suggest that organic selenium can improve M. salmoides muscle quality through the aforementioned pathways, which provides potential insights into the improvement of the quality of aquatic products, especially fish.

Effects of temporary rearing with organic selenium on the muscle flavor and texture properties of largemouth bass (Micropterus salmonides).

In this study, the influences of organic selenium (Se, 0.002 mg/L) on the muscle flavor and texture properties of Micropterus salmonides under fasting temporary rearing (8 weeks) was investigated. Electronic nose and headspace solid-phase microextraction-gas chromatography-mass spectrometry analysis suggested that organic Se regulated the types and contents of volatile compounds, especially aldehydes and ketones, which were increased in the early temporary rearing but decreased in the late stage. Organic Se significantly increased the content of 5'-inosine monophosphate by approximately 15 % (p < 0.05), and decreased the content of hypoxanthine and hypoxanthine ribonucleoside by more than 20 % (p < 0.05). After the 8th temporary rearing week, muscle hardness and springiness increased by at least 10 % (p < 0.01), resilience and gumminess improved by at least 18 % (p < 0.05) and 5.9 % (p < 0.05), respectively. In conclusion, organic Se ameliorates the flesh quality of M. salmonides during long-term temporary rearing.

Antioxidant and antitumor activities of water extracts from the root of Actinidia kolomikta.

The genus of Actinidia is widely distributed throughout the Asian continent. Specific Actinidia species have been used as health foods and medical products for cancer treatment. Actinidia kolomikta is a species of wild plant that grows in the northern part of Indochina. However, few studies on its bioactivity have been reported. In this study, the polysaccharide and polyphenol contents, the SOD-like activity and the DPPH radical-scavenging activity of water extracts from the root of Actinidia kolomikta produced under different extraction temperatures were investigated. Furthermore, the water extraction-ethanol precipitate (WE-EP) fraction and the water extraction-ethanol supernatant (WE-ES) fraction were used to test the anti-proliferative action on DLD-1 colon cancer cells. Extracts produced using the 100°C extraction procedure revealed higher extraction yields and antioxidant activities than extracts produced using the 40°C extraction procedure. The WE-EP and WE-ES fractions exhibited anti-proliferative effects on the DLD-1 cells. Moreover, the WE-ES polyphenol-enriched fraction possessed more potent anti-proliferative effects on the DLD-1 cells by inducing apoptosis compared to the WE-EP polysaccharide fraction. Medicinal plant extracts are generally considered to be relatively non-toxic at low doses and are not thought to cause major side effects compared to those observed with drugs. Wild A. kolomikta may provide an alternative to currently employed cancer therapies, and may be used as a natural health food with antioxidant actions.

Anthocyanins extracted from Chinese blueberry (Vaccinium uliginosum L.) and its anticancer effects on DLD-1 and COLO205 cells.

BACKGROUND: Vaccinium uliginosum L. is a type of blueberry found in the Chinese Changbai Mountains. We extracted Vaccinium uliginosum Anthocyanins (A(V.uli)) to investigate its bioactivity on suppressing cancer cells. METHODS: A(V.uli) was extracted under different conditions of temperature (10°C - 35°C), pH 1.0 - 3.0, and diatomaceous earth (1.0 g - 3.0 g), followed by a HPLC analysis for the determination of the ingredients. Its anticancer bioactivities on human colon and colorectal cancer cells (DLD-1 and COLO205) were compared with those on Lonicera caerulea Anthocyanins (A(L.cae)) and Vaccinium myrtillus Anthocyanins (A(V.myr)), using cell viability assays, DNA electrophoresis and nuclear morphology assays. RESULTS: The optimum process of A(V.uli) extraction involved conditions of temperature 20°C, pH 2.0, and diatomaceous earth 1.0 g/50 g of fruit weight. A(V.uli) contained 5 main components: delphinidin (40.70 ± 1.72)%, cyanidin (3.40 ± 0.68)%, petunidin (17.70 ± 0.54)%, peonidin (2.90 ± 0.63)% and malvidin (35.50 ± 1.11)%. The malvidin percentage was significantly higher (P < 0.05) than it in A(V.myr). A(V.uli) complied with a dose-dependent repression of cancer cell proliferation with an IC(50) (50% inhibitory concentration) value of 50 µg/ml, and showed greater anticancer efficiency than A(L.cae) and A(V.myr) under the same cell treatment conditions. These observations were further supported by the results of nuclear assays. CONCLUSIONS: The extraction protocol and conditions we used were effective for anthocyanin extraction. A(V.uli) could be a feasible practical research tool and a promising therapeutic source to suppress human colon or colorectal cancers.