Nannochloropsis gaditana and Crypthecodinium cohnii, two microalgae as alternative sources of essential fatty acids in early weaning for gilthead seabream

In this study, the feasibility of the use of heterotrophic dinoflagellate Crypthecodinium cohnii and phototrophic eustigmataceae Nannochloropsis gaditana as a partial or total substitute for fish oil in weaning diets of gilthead sea bream is evaluated. 20 day old larvae were fed with the following microdiets: a control diet based on fish oil, two diets with 11% dry weight of N. gaditana or with 8% of C. cohnii as substitutes for fish oil (diets N and C, respectively), and one last diet that combined N. gaditana (5.5%) and C. cohnii (5.5%) with fish oil (5.5%, diet N+C). At the end of the experiment (after 17 days of treatment), the survival did not differ among the groups, but the total length growth and dry weight of the larvae fed with fish oil and C. cohnii were superior to that of those fed with N. gaditana (p < 0.05). The analysis of fatty acids confirmed that C. cohnii and N. gaditana were used as a source of fatty acids essential in the microdiets of the larvae of gilthead sea bream. The results of this study revealed that the eicosapentaenoic acid (EPA; 20:5n-3) provided by N. gaditana allows the survival of the larvae, and that the docosahexaenoic acid (DHA; 22:6n-3) provided by C. cohnii is necessary in weaning diets in the gilthead sea bream in order to maintain the optimal growth of the larvae

Omega-3 eicosapentaenoic acid (Epa) rich extract from the microalga nannochloropsis decreases cholesterol in healthy individuals: A double-blind, randomized, placebo-controlled, three-month supplementation study

The aim of this trial is to assess the effect of AlmegaPL on improving the Omega-3 Index, cardio-metabolic parameters, and other biomarkers in generally healthy individuals. The benefits of long-chain omega-3 fatty acids for cardiovascular health are primarily built upon mixtures of docosahexaenoic (DHA) and eicosapentaenoic acids (EPA). Highly purified EPA therapy has proven to be particularly effective in the treatment of cardiovascular disease, but less is known about the benefits of EPA-only supplementation for the general healthy population. AlmegaPL is a polar rich oil (>15%) derived from the microalga Nannochloropsis that contains EPA (>25%) with no DHA. Participants (n = 120) were given a capsule of 1 g/day of either AlmegaPL or placebo for 12 weeks. Differences in the Omega-3 Index, cardiometabolic markers, and other general health indicators were measured at the baseline, six, and 12 weeks. Compared to the placebo group, AlmegaPL supplementation significantly increased the Omega-3 Index and EPA concentration from 4.96 ± 0.90 and 0.82 ± 0.37% at the baseline to 5.75 ± 0.90 and 1.27 ± 0.36 at week 12, respectively. Very-low-density lipoprotein cholesterol (VLDL) decreased by 25%, which resulted in a significant decrease in total cholesterol compared to the placebo. Interestingly, the decrease in VLDL was not associated with an increase in LDL, which seems to be a benefit associated with EPA-only based formulations. Collectively, these results show that AlmegaPL provides a natural EPA-only option to increase EPA and manage cholesterol levels in the general population

Nannochloropsis gaditana and Crypthecodinium cohnii, two microalgae as alternative sources of essential fatty acids in early weaning for gilthead seabream

In this study, the feasibility of the use of heterotrophic dinoflagellate Crypthecodinium cohnii and phototrophic eustigmataceae Nannochloropsis gaditana as a partial or total substitute for fish oil in weaning diets of gilthead sea bream is evaluated. 20 day old larvae were fed with the following microdiets: a control diet based on fish oil, two diets with 11% dry weight of N. gaditana or with 8% of C. cohnii as substitutes for fish oil (diets N and C, respectively), and one last diet that combined N. gaditana (5.5%) and C. cohnii (5.5%) with fish oil (5.5%, diet N+C). At the end of the experiment (after 17 days of treatment), the survival did not differ among the groups, but the total length growth and dry weight of the larvae fed with fish oil and C. cohnii were superior to that of those fed with N. gaditana (p < 0.05). The analysis of fatty acids confirmed that C. cohnii and N. gaditana were used as a source of fatty acids essential in the microdiets of the larvae of gilthead sea bream. The results of this study revealed that the eicosapentaenoic acid (EPA; 20:5n-3) provided by N. gaditana allows the survival of the larvae, and that the docosahexaenoic acid (DHA; 22:6n-3) provided by C. cohnii is necessary in weaning diets in the gilthead sea bream in order to maintain the optimal growth of the larvae

Stress response in sea bream (Sparus aurata) held under crowded conditions and fed diets containing linseed and/or soybean oil

The physiological response to stressors in fish, including hormonal profiles and associated tissue responsiveness, is less documented. The aim of this study was to evaluate feeding gilthead sea bream (Sparus aurata) with diets containing linseed oil (LO) and soybean oil (SO) as substitutes to fish oil (FO) and their effect on fatty acid profile of head kidney and the consequent effect on stress response to a crowding challenge. Fish were fed 8 experimental diets with different levels of substitution 0% (FO), 70% (70LO, 70SO, 20LO50SO and 50LO20SO) and 100% (100LO, 100SO and 50LO50SO) over a period of 8 months. At the end of the feeding trial, samples of head kidney were collected for biochemical analysis and the fish were challenged by a crowding test. During the challenge, samples of plasma for cortisol analysis were collected at 0 h, 2 h, 5 h, 24 h, 48 h and 1 week in order to study acute and chronic stress responses. Results showed that fish fed vegetable oils (VO) had significantly decreased ARA, EPA, DHA and n-3 HUFA, while LA, LNA and total C18 PUFAs were significantly increased. The basal cortisol levels were significantly increased in fish fed 70LO, 100LO, 50LO20SO and 50LO50SO. The physiological response to crowding was significantly affected by the diet. After 2 h of crowding, all the treatments showed higher cortisol, with fish fed 100LO had significantly the highest response registering 131.38 pg/ml. After 5 h and 24 h, plasma cortisol was reduced in all treatments except in 50LO20SO. After 48 h of crowding, the plasma cortisol was increased in all treatments with the maximum value seen in fish fed 100LO (72.12 pg/ml). These levels were decreased in fish fed FO, 70LO, 100LO and 50L050SO after 1 week of crowding, but remained higher in fish fed 70SO, 100SO, 20LO50SO and 50LO20SO. In conclusion, fish fed LO diets showed the same response pattern as the control but with higher intensity regaining the basal levels after 1 week as the control, while fish fed SO had a slow response but changed the pattern characterized by a lower response at the beginning and longer recuperation without regaining the control value even after 1 week