Microalgae as a safe food source for animals: nutritional characteristics of the acidophilic microalgaCoccomyxa onubensis

Abstract

BackgroundEdible microalgae are marine or fresh water mesophilic species. Although the harvesting of microalgae offers an abundance of opportunities to the food and pharmaceutical industries, the possibility to use extremophilic microalgae as a food source for animals is not well-documented.ObjectiveWe studied the effects of dietary supplementation of a powdered form of the acidophilic microalga Coccomyxa onubensis on growth and health parameters of laboratory rats.MethodFour randomly organized groups of rats (n=6) were fed a standard diet (Diet 1, control) or with a diet in which 0.4% (Diet 2), 1.25% (Diet 3), or 6.25% (Diet 4) (w/w) of the standard diet weight was substituted with dried microalgae powder, respectively. The four groups of animals were provided ad libitum access to feed for 45 days.ResultsC. onubensis biomass is rich in protein (44.60% of dry weight) and dietary fiber (15.73%), and has a moderate carbohydrate content (24.8%) and a low lipid content (5.4%) in which polyunsaturated fatty acids represent 65% of the total fatty acid. Nucleic acids are present at 4.8%. No significant difference was found in growth rates or feed efficiency ratios of the four groups of rats. Histological studies of liver and kidney tissue revealed healthy organs in control and C. onubensis-fed animals, while plasma hematological and biochemical parameters were within healthy ranges for all animals. Furthermore, animals fed a microalgae-enriched diet exhibited a statistically significant decrease in both blood cholesterol and triglyceride levels. The blood triglyceride content and very low density lipoprotein-cholesterol levels decreased by about 50% in rats fed Diet 4.ConclusionsThese data suggest that C. onubensis may be useful as a food supplement for laboratory animals and may also serve as a nutraceutical in functional foods. In addition, microalgae powder-supplemented diets exerted a significant hypocholesterolemic and hypotriglyceridemic effect in animals.

Microalgal-based feed: promising alternative feedstocks for livestock and poultry production

“…Feed stocks containing higher concentrations of methionine and lysine have been found to increase chicken breast and thigh muscles and improve the quality and quantity of meat. Microalgae also produce bioactive peptides with antioxidative, antihypertensive, anticoagulative, antitumor and immune-simulative properties [ 11 , 36 ]. The most widely used microalgae for protein-rich feed supplements include species of Chlorella , Arthrospira , Dunaliella , Tetraselmis , Phaeodactylum , Skeletonema , and Scenedesmus [ 37 , 38 ].…”

“…Moreover, it was stated that microalgae feed-supplement (i) presents cholesterol-lowering effect in animals, (ii) improves immune response [ 4 ], (iii) enhances milk quality and production yield in cows [ 5 ], (iv) promotes animal growth and improves meat and egg quality [ 6 ], (v) offers resistance to disease through antiviral and antibacterial action [ 7 ], (vi) improves gut function [ 8 ], (vii) enriches the colonization of probiotics [ 8 , 9 ] and increases feed conversion [ 10 ]. Furthermore, it was recently proved that algae-based feed increases reproductive performance and helps in weight control [ 11 ].…”

Outdoor Large-Scale Cultivation of the Acidophilic Microalga Coccomyxa onubensis in a Vertical Close Photobioreactor for Lutein Production

“…Among the potential applications of this microalga, an antibacterial effect against human pathogens has been reported by Navarro et al [13], and microalgal fatty acids were suggested to be involved in the antibacterial activity. Although the mechanisms through which fatty acids may exert bactericidal activity are not fully understood, it has been reported they may promote membrane damage resulting in nutrient uptake alteration and cellular respiration inhibition [14]. In addition, this microalga could be also attractive as a nutritional supplement for food and feed industries [14].…”

“…Although the mechanisms through which fatty acids may exert bactericidal activity are not fully understood, it has been reported they may promote membrane damage resulting in nutrient uptake alteration and cellular respiration inhibition [14]. In addition, this microalga could be also attractive as a nutritional supplement for food and feed industries [14]. These data indicate the potential of C. onubensis as source of valuable compounds and highlight the interest of producing its biomass at large-scale.…”

Advanced Production Technology of Flour-Based Foods with Chlorella Concentrate

“…На территории Российской Федерации хлорелла употребляется в качестве самостоятельной биологически активной добавки, а не ингредиента для приготовления кулинарной продукции и блюд. Одна из причин возникновения данного явления в нашей стране -недостаточный уровень знаний о хлорелле и её свойствах, в отличие от Японии, где хлореллу часто применяют в промышленных масштабах пищевых направлений [11]. Российский потребитель знаком с хлореллой только как с полноценным продуктом, который употребляется непосредственно внутрь без проведения дополнительных операций.…”