Hypocholesterolemic Effects of Nutraceuticals Produced from the Red Microalga Porphyridium sp in Rats

Red microalgae contain functional sulfated polysaccharides (containing dietary fibers), polyunsaturated fatty acids, zeaxanthin, vitamins, minerals, and proteins. Studies in rat models support the therapeutic properties of algal biomass and isolated polysaccharides. Algal products incorporated into rat diets were found to significantly improve total serum cholesterol, serum triglycerides, hepatic cholesterol levels, HDL/LDL ratios and increased fecal excretion of neutral sterols and bile acids. Morphological and metabolic changes were induced by consumption of algal products. These results suggest that red microalgae can be used as potent hypocholesterolemic agents, and they support the potential use of red microalgae as novel nutraceuticals

Algal food and fuel coproduction can mitigate greenhouse gas emissions while improving land and water-use efficiency

The goals of ensuring energy, water, food, and climate security can often conflict.Microalgae (algae) are being pursued as a feedstockfor both food and fuels—primarily due to algae’s high areal yield and ability to grow on non-arable land, thus avoiding common bioenergy-food tradeoffs. However, algal cultivation requires significant energy inputs that may limit potential emission reductions.We examine the tradeoffs associated with producing fuel andfood from algae at the energy–food–water–climate nexus.We use the GCAM integrated assessment model to demonstrate that algalfood production can promote reductions in land-use change emissions through the offset of conventional agriculture. However,fuel production, either via co-production of algal food and fuel or complete biomass conversion to fuel, is necessary to ensure long-term emission reductions, due to the high energy costs of cultivation. Cultivation of salt– water algae for food products may lead to substantial freshwater savings; but, nutrients for algae cultivation will need to be sourced from waste streams to ensure sustainability. By reducing the land demand of food production, while simultaneously enhancingfood and energy security, algae can further enable the development of terrestrial bioenergy technologies including those utilizing carbon capture and storage. Our results demonstrate that large-scale algae research and commercialization efforts should focus on developing both food and energy products to achieve environmental goals.https://iopscience.iop.org/article/10.1088/1748-9326/11/11/114006/metaPublished versio

Algal biomass and its commercial utilisation

Algal biomass is a source of high value products worth over A$100 x 10 6 per annum. Red and brown seaweeds yield the phycocolloids, which are used as gelling, viscosity and clarifying agents in the food, cosmetic and pharmaceutical industries. Microalgal products in the health food market include Spirulina and Chlorella powder and tablets. The blue phycocyanin pigment extracted from Spirulina is used as a food colouring, and P-carotene extracted from Dunaliella salina, is sold as a yellow food colouring, and for its provitamin A and anti-oxidant properties in nutritional supplements. Development of new intensive culture systems is expected to widen the range of commercial algal products in the future

Processing of astaxanthin-rich Haematococcus cells for dietary inclusion and optimal pigmentation in Rainbow trout, Onchorynchus mykiss L.

A range of physical cell disruption techniques have been evaluated to aid the processing of astaxanthin-rich haematocysts of Haematoccus pluvialis for inclusion in salmonid feeds. Cell disruption by a scaleable pressure treatment system was shown to be effective in breaking open the haematocysts without altering the content or isomeric composition of carotenoids in the algal cells. Storage of disrupted cells was optimal at -20°C in the dark under nitrogen. Disrupted cells were spray-dried, incorporated into commercial diets and fed to Rainbow trout (Onchorynchus mykiss L). A marketable level of pigmentation in fish muscle was achieved after 10 weeks dietary supplementation. The geometric and optimal isomer composition of the astaxanthin deposited in the muscle was nearly identical to that seen in Haematococcus. Changes were observed in the chirality of the astaxanthin deposited in the skin in comparison to that isolated from both the white muscle and the alga

Microalgae-utilizing biorefinery concept for pulp and paper industry: Converting secondary streams into value-added products

Traditional pulp and paper industry is in transition due to increased competition and changes in consumption habits. Advanced biorefining is seen as one option to create new business opportunities. This article presents a microalgae-utilizing biorefinery which is integrated into a traditional pulp and paper mill and which produces high-value algal products, fertilizer and biogas from secondary process streams. Presented biorefinery process is validated with mass balances, employing initial data from a Scandinavian pulp and paper mill. Results indicate that the proposed process is technically viable. Production potential is sensitive to light and nutrient availability in algae cultivation, and seasonal changes in irradiance result in significant output variation. The biorefinery process can be generalized to other process industry and wastewater treatment plants that have similar output flows.Peer reviewe

Organic carbon release by phytoplankton and bacterial reassimilation

L'excrétion organique du carbone par le phytoplancton et sa réassimilation par les bactéries ont été étudiées sur le lac Léman. La Gentamyane a été utilisée comme inhibiteur de l'activité bactérienne tandis que des fractionnements par classes de tailles ont permis de distinguer les compartiments phyto et bactérioplanctoniques. Les performances de ces méthodes sont discutées. Le phytoplancton collecté à différentes périodes de l'année excrète moins de 20% de son carbone photoassimilé. La majeure partie (33 à 100%) de cette excrétion est réassimilée par les bactéries en une journée. Le protocole utilisé à permis d'accéder à une excrétion brute. (Résumé d'auteur

Potentiality of Using Spreading Sargassum Species From Indonesia as an Interesting Source of Antibacterial and Radical Scavenging Compounds: a Preliminary Study

As an archipelagic country with 95,181 km long coastline, Indonesia has great potential as the producer of seaweeds. The diverse phyla of marine macroalgae (red, brown and green seaweeds) are known to produce molecules which are attractive for diverse industries. Applications of algal products range from simple biomass production for food, feed and fuels to valuable products such as sugar polymers, cosmetics, pharmaceuticals, pigments, and food supplements. Seaweeds also have the potential to be used as a source of new bioactive for human, animal or plant health, as well as a source of new synthons and biocatalysts in sustainable chemistry (Bourgougnon and Stiger-Pouvreau, 2011). In this paper, among species of economic value we focus on brown seaweeds belonging to family Sargassaceae and genus Sargassum spreading along Indonesian coasts. Members of this genus are especially abundant in tropical and subtropical regions (Zemke-White and Ohno, 1999). The purpose of this study is to analyze the antibacterial and antioxidant activity of three species of Sargassum, i.e. S. echinocarpum, S. duplicatum and S. polycystum. Both polar and non-polar extracts have been prepared from those three species. In vitro antibacterial activities of extracts were evaluated against Gram-positive bacteria Staphylococcus aureus and Gram-negative bacteria Escherichia coli. Results indicated all the three species tested showed an antibacterial activity. The most effective antibacterial activity against S. aerous was from S. echinocarpum with ethil asetat, inhibition zone 1.13 ± 0.25 mm; S. duplicatum with N-Hexane was most effective against E. coli, 1.20 ± 0.28 mm

Green genes: bioinformatics and systems-biology innovations drive algal biotechnology.

Many species of microalgae produce hydrocarbons, polysaccharides, and other valuable products in significant amounts. However, large-scale production of algal products is not yet competitive against non-renewable alternatives from fossil fuel. Metabolic engineering approaches will help to improve productivity, but the exact metabolic pathways and the identities of the majority of the genes involved remain unknown. Recent advances in bioinformatics and systems-biology modeling coupled with increasing numbers of algal genome-sequencing projects are providing the means to address this. A multidisciplinary integration of methods will provide synergy for a systems-level understanding of microalgae, and thereby accelerate the improvement of industrially valuable strains. In this review we highlight recent advances and challenges to microalgal research and discuss future potential.We acknowledge support from the EU FP7 project SPLASH (Sustainable PoLymers from Algae Sugars and Hydrocarbons), grant agreement number 311956.This is the accepted manuscript. The final version is available from Cell/Elsevier at http://www.sciencedirect.com/science/article/pii/S016777991400196