Enzymatic Hydrolysis of Orange-Footed Sea Cucumber (Cucumaria frondosa)-Effect of Different Enzymes on Protein Yield and Bioactivity.

While sea cucumber is a food delicacy in Asia, these food resources are less exploited in Europe. The aim of this study was to determine the chemical composition and potential food applications of the less exploited orange-footed sea cucumber (Cucumaria frondosa). In particular, the antioxidative capacity and free amino acids associated with the umami flavor released by enzymatic hydrolyses by either Bromelain + Papain (0.36%, 1:1) or Alcalase (0.36%) were studied. Fresh C. frondosa contained approximately 86% water, and low levels of ash (<1%) and lipids (<0.5%). The protein content was 5%, with a high proportion of essential amino acids (43%) and thus comparable to the FAO reference protein. The high concentration of free amino acids associated with umami, sour, sweet, and bitter may contribute to flavor enhancement. Hydrolysis by Bromelain + Papain resulted in the highest protein yield, and the greatest concentration of free amino acids associated with umami and sour taste. All samples showed promising antioxidant capacity measured by FRAP, ABTS, DPPH and ORAC compared to previous reports. The inorganic arsenic concentration of fresh C. frondosa ranged from 2 to 8 mg/kg wet weight and was not affected by processing. This is comparable to other seafood and may exceed regulatory limits of consumption.

Effect of Different Drying Methods on the Nutritional Value of Hibiscus sabdariffa Calyces as Revealed by NMR Metabolomics.

Red mature calyces of Hibiscus sabdariffa were collected from 16 different locations in Meghalaya, India. Samples were processed using shade drying (SD) and tray drying (TD). NMR spectroscopy was used to assess the metabolic composition of the calyces. In this study, 18 polar metabolites were assigned using 1D and 2D NMR spectra, and 10 of them were quantified. Proximate analysis showed that the TD method is more efficient at reducing moisture and maintaining the ash content of the Hibiscus biomass. NMR metabolomics indicates that the metabolite composition significantly differs between SD and TD samples and is more stable in TD plant processing. The differences in post-harvest drying has a greater impact on the metabolite composition of Hibiscus than the plant location.

Inhibitory effects of kiwifruit extract on human platelet aggregation and plasma angiotensin-converting enzyme activity.

Previous human studies suggest that supplementation with kiwifruits lowers several cardiovascular risk factors such as platelet hyperactivity, blood pressure and plasma lipids. The cardiovascular health benefit of fruit and vegetables is usually attributed to the complex mixture of phytochemicals therein; however, kiwifruit's cardioprotective factors are not well studied. In this study, we investigated the effects of kiwifruit extract on human blood platelet aggregation and plasma angiotensin-converting enzyme (ACE) activity. A sugar-free, heat-stable aqueous extract with molecular mass less than 1000 Da was prepared from kiwifruits. Typically, 100 g kiwifruits produced 66.3 ± 5.8 mg (1.2 ± 0.1 mg CE) of sugar-free kiwifruit extract (KFE). KFE inhibited both human platelet aggregation and plasma ACE activity in a dose-dependent manner. KFE inhibited platelet aggregation in response to ADP, collagen and arachidonic acid, and inhibitory action was mediated in part by reducing TxA2 synthesis. The IC50 for ADP-induced platelet aggregation was 1.6 ± 0.2 mg/ml (29.0 ± 3.0 µg CE/ml), whereas IC50 for serum ACE was 0.6 ± 0.1 mg/ml (11.0 ± 1.2 µg CE/ml). Consuming 500 mg of KFE (9.0 mg CE) in 10 g margarine inhibited ex vivo platelet aggregation by 12.7%, 2 h after consumption by healthy volunteers (n = 9). All these data indicate that kiwifruit contains very potent antiplatelet and anti-ACE components. Consuming kiwifruits might be beneficial as both preventive and therapeutic regime in cardiovascular disease.

Effects of similar intakes of marine n-3 fatty acids from enriched food products and fish oil on cardiovascular risk markers in healthy human subjects.

There is convincing evidence that consumption of fish and fish oil rich in long-chain (LC) n-3 PUFA (n-3 LCPUFA), EPA (20 : 5n-3) and DHA (22 : 6n-3) reduce the risk of CHD. The aim of the present study was to investigate whether n-3 LCPUFA-enriched food products provide similar beneficial effects as fish oil with regard to incorporation into plasma lipids and effects on cardiovascular risk markers. A parallel 7-week intervention trial was performed where 159 healthy men and women were randomised to consume either 34 g fish pâté (n 44), 500 ml fruit juice (n 38) or three capsules of concentrated fish oil (n 40), all contributing to a daily intake of approximately 1 g EPA and DHA. A fourth group did not receive any supplementation or food product and served as controls (n 37). Plasma fatty acid composition, serum lipids, and markers of inflammation and oxidative stress were measured. Compared with the control group, plasma n-3 LCPUFA and EPA:arachidonic acid ratio increased equally in all intervention groups. However, no significant changes in blood lipids and markers of inflammation and oxidative stress were observed. In conclusion, enriched fish pâté and fruit juice represent suitable delivery systems for n-3 LCPUFA. However, although the dose given is known to reduce the risk of CVD, no significant changes were observed on cardiovascular risk markers in this healthy population.