Availability and Utilization of Pigments from Microalgae

Dual functions of eicosapentaenoic acid-rich microalgae: enrichment of yolk with n-3 polyunsaturated fatty acids and partial replacement for soybean meal in diet of laying hens

Microalgae (Nannochloropsis sp., NS), with high contents of eicosapentaenoic acid (EPA) and crude protein, may be one of the important n-3 polyunsaturated fatty acid (PUFA) sources and potential protein feed ingredient. The purposes of this study were to enrich yolk with n-3 PUFA by dietary EPA-rich NS supplementation and to evaluate whether it is feasible to partly substitute for soybean meal in laying hens diet. A total of 360 37-wk-old healthy Lohmann Brown laying hens, with similar laying rate and body weight, were randomly allotted to 5 groups (6 replicates, 12 birds/replicate) and fed 5 experimental diets (0, 1, 2, 4, and 8% NS) for 4 wk. The hen performance and egg quality (except yolk color) were not affected (P > 0.05) by the NS supplemental diets. Yolk color score was increased as NS supplementation in diets (P < 0.001), and peaked on about the seventh day in all NS supplemental groups. The concentration of total n-3 PUFA was increased (P < 0.001), while total n-6 PUFA and n-6/n-3 ratio were decreased (P < 0.001) in yolk with increasing NS levels in diets. The 8% NS group had highest docosahexaenoic acid (DHA) and total n-3 PUFA levels, reaching 111.6 mg DHA and 148.6 mg total n-3 PUFA per egg. Maximum DHA, total n-3 PUFA, very long-chain (LC-) n-3 PUFA, and LC-PUFA levels were all observed at day 13 of NS supplementation. In conclusion, dietary NS supplementation enriched yolk with n-3 PUFA (especially DHA) and enhanced yolk color score without adverse effects on performance and egg quality, and indicated the practical feasibility of partial replacement for soybean meal in laying hens diet.

Metabolite Profiling of the Microalgal Diatom Chaetoceros Calcitrans and Correlation with Antioxidant and Nitric Oxide Inhibitory Activities via ¹H NMR-Based Metabolomics

Microalgae are promising candidate resources from marine ecology for health-improving effects. Metabolite profiling of the microalgal diatom, Chaetoceros calcitrans was conducted by using robust metabolomics tools, namely ¹H nuclear magnetic resonance (NMR) spectroscopy coupled with multivariate data analysis (MVDA). The unsupervised data analysis, using principal component analysis (PCA), resolved the five types of extracts made by solvents ranging from polar to non-polar into five different clusters. Collectively, with various extraction solvents, 11 amino acids, cholesterol, 6 fatty acids, 2 sugars, 1 osmolyte, 6 carotenoids and 2 chlorophyll pigments were identified. The fatty acids and both carotenoid pigments as well as chlorophyll, were observed in the extracts made from medium polar (acetone, chloroform) and non-polar (hexane) solvents. It is suggested that the compounds were the characteristic markers that influenced the separation between the clusters. Based on partial least square (PLS) analysis, fucoxanthin, astaxanthin, violaxanthin, zeaxanthin, canthaxanthin, and lutein displayed strong correlation to 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and nitric oxide (NO) inhibitory activity. This metabolomics study showed that solvent extractions are one of the main bottlenecks for the maximum recovery of bioactive microalgal compounds and could be a better source of natural antioxidants due to a high value of metabolites.

Bio-Based Products from Microalgae Cultivated in Digestates

In recent years the increasing demand for food, energy, and valuable chemicals has necessitated research and development on renewable, novel, and sustainable sources. Microalgae represent a promising option to produce various products with environmentally friendly applications. However, several challenges must be overcome to reduce production cost. To this end, using effluents from biogas production units, called digestates, in cultivation systems can help to optimize bioprocesses, and several bioproducts including biofuels, biofertilizers, proteins and valuable chemicals can be obtained. Nevertheless, several parameters, including the productivity and quality of biomass and specific target products, downstream processes, and cost-effectiveness, must be improved. Further investigations will be necessary to take full advantage of the produced biomass and effectively upscale the process.

Effects of different light source and media on growth and production of phycobiliprotein from freshwater cyanobacteria

The aim of this study was to determine the effect of different light sources and media (wastewater and BBM) on the growth of Pseudanabaena mucicola and its phycobiliprotein production. Results showed that P. mucicola grown in white light using wastewater as medium attributed higher biomass (0.55 g L^-1) and when extracted with water, also showed significantly higher (P < .05) production (237.01 mg g^-1) and purity (1.14) of phycobiliprotein. This study validated that phycobiliprotein extracted from P. mucicola using water can be food grade natural blue pigment. Moreover, cyanobacteria grown in wastewater could cut down the production cost of phycobiliprotein.

Markers of Hypoxia and Oxidative Stress in Aging Volunteers Ingesting Lycosomal Formulation of Dark Chocolate Containing Astaxanthin

OBJECTIVE

To determine if ingestion of lycosome-formulated dark chocolate (DC) containing astaxanthin (ASTX) improves bioavailability of ASTX and affects markers of hypoxia and oxidative stress in aging individuals.

DESIGN

Randomized, blinded, four-arm, prospective study.

SETTINGS

Lycotec Ltd, Cambridge, United Kingdom and Institute of Cardiology, Saratov, Russian Federation.

PARTICIPANTS

32 healthy individuals aged 60-70 years with confirmed signs of oxidative stress (increased serum levels of oxidized LDL and malonic dialdehyde) randomized into four study groups (8 volunteers each).

INTERVENTION

Volunteers of first group were given orally 10 gr of dark chocolate (DC). Individuals from the second group received 7 mg of astaxanthin (ASTX). Third group of volunteers was supplemented with 10 gr of DC and 7 mg of ASTX ingested simultaneously as two separate formulations. Last group of the individuals was given 10 gr of a lycosomal formulation of DC containing 7 mg of co-crystalized ASTX (L-DC-ASTX), a newly developed highly bioavailable nutraceutical composition of DC containing 2 groups of antioxidants (cocoa flavanols and ASTX). All formulations were given orally, once daily for a month.

MEASUREMENTS

Serum ASTX was measured by high-performance liquid chromatography. Nitric oxide, malonic dialdehyde and oxidized LDL were quantified spectrophotometrically. Oxygenation parameters were evaluated by near-infrared spectroscopy.

RESULTS

One month ingestion of singular formulation of ASTX lead to a 20 fold buildup in serum ASTX level whereas the 4 week ingestion of L-DC-ASTX formulation was accompanied by more prominent accumulation of ASTX in serum (a 40 fold increase over the basal values) at the same daily dose of ASTX. Both antioxidants taken separately decreased serum levels of oxidized LDL and malonic dialdehyde. However effect of L-DC-ASTX formulation was more prominent. ASTX ingested alone caused a borderline increase (p=0.054) in serum nitric oxide (NO) levels, whereas DC ingestion lead to small but statistically significant increase in serum NO concentration. Higher values of NO level were seen after co-ingestion of DC and ASTX, especially in case of L-DC-ASTX formulation suggesting additive/synergistic effects of DC and ASTX on nitric oxide production. These changes were in agreement with the increase in plasma oxygen transport and tissue oxygen saturation seen in the volunteers supplemented with L-DC-ASTX formulation.

CONCLUSION

The nutraceutical formulation of DC and ASTX with an enhanced bioavailability of ASTX can be efficiently used for the correction of oxidative status in aging individuals.

Microalgae, old sustainable food and fashion nutraceuticals

Microalgae have been used for centuries to provide nourishment to humans and animals, only very recently they have become much more widely cultured and harvested at large industrial scale. This paper reviews the potential health benefits and nutrition provided by microalgae whose benefits are contributing to expand their market. We also point out several key challenges that remain to be addressed in this field.

Bioactive Compounds Isolated from Microalgae in Chronic Inflammation and Cancer

The risk of onset of cancer is influenced by poorly controlled chronic inflammatory processes. Inflammatory diseases related to cancer development include inflammatory bowel disease, which can lead to colon cancer, or actinic keratosis, associated with chronic exposure to ultraviolet light, which can progress to squamous cell carcinoma. Chronic inflammatory states expose these patients to a number of signals with tumorigenic effects, including nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPK) activation, pro-inflammatory cytokines and prostaglandins release and ROS production. In addition, the participation of inflammasomes, autophagy and sirtuins has been demonstrated in pathological processes such as inflammation and cancer. Chemoprevention consists in the use of drugs, vitamins, or nutritional supplements to reduce the risk of developing or having a recurrence of cancer. Numerous in vitro and animal studies have established the potential colon and skin cancer chemopreventive properties of substances from marine environment, including microalgae species and their products (carotenoids, fatty acids, glycolipids, polysaccharides and proteins). This review summarizes the main mechanisms of actions of these compounds in the chemoprevention of these cancers. These actions include suppression of cell proliferation, induction of apoptosis, stimulation of antimetastatic and antiangiogenic responses and increased antioxidant and anti-inflammatory activity.