The Effect of Gibberellic Acid on the Production Characteristics and Biochemical Parameters of Tetraselmis Suecica in an Enrichment Culture

The use of gibberellic acid as a stimulator of microalgae growth has beensubstantiatedexperimentally.This research aimed to assess the effect of exposure to a wide range of gibberellic acid concentrations on the growth dynamics ofthe microalgaTetraselmissuecicain an enrichment culture. The duration of the experiments was 14 days. It has been shown that gibberellic acid,atconcentrations of 0.39–3.20× 10−8M, stimulates algaegrowth. In this research, the exposure to gibberellic acid at concentrations of 0.39–3.20 × 10−8M was accompanied by a variation in the pattern of growth curves: the maximum number of cells was recorded on day seven of the experiment. A higher concentration of the phytohormone (3.84 × 10−8М) inhibited the increase inculture density. The growth of theT. suecicaculture in the control group was 332%;the growth of the culture exposed to gibberellic acid at a concentration of 0.39 × 10−8M was1136%. The values of the specific growth rate ofT. suecicawere estimated for different periods of cultivation. On day14 of the experiment, the biochemical composition of microalgae biomass was analyzed.According to the results, gibberellic acid stimulated the accumulation of carbohydrates, proteins, and chlorophyll. Nevertheless, the phytohormone had no effect on lipidaccumulation. An assumption was made thatexposure to low concentrations of phytohormone stimulates the growth of microalgae by reducing the lag phase of growth. Keywords: gibberellic acid, microalga, cultivation, lipids, carbohydrates, proteins

Disintegration of wet microalgae biomass with deep-eutectic-solvent-assisted hydrothermal treatment for sustainable lipid extraction

Deep eutectic solvent (DES) with abundant hydrogen bond acceptors and donors was employed to promote disintegration of microalgae biomass with hydrothermal treatment (HTT) for green lipid extraction. The lipid extraction...

Mass Transfer Features of Wavy-Bottomed Cascade Photobioreactors

It has been suggested that the energy-efficient production of microalgae biomass can be more easily obtained in short light path photobioreactors that can be operated at high biomass concentration. On the downside, however, high biomass concentrations also require an efficient gas exchange rate to avoid metabolic growth limitation or inhibition. A cascade photobioreactor featuring a thin liquid layer flowing down a sloping, wavy-bottomed surface can be operated at a biomass concentration that is much higher compared to most usual open-type equipment. Liquid flow, upon investigation, proved to exhibit peculiar “local recirculation” hydrodynamics, potentially conducive to the mixing of superficial and deep zones of the photobioreactor. Mass transfer coefficient represents a useful parameter to optimize the performance of a microalgal photobioreactor and its scale-up. The aim of the present article is to discuss the experimental mass transfer features of this novel type of photobioreactor and highlight expected opportunities and issues entailed by different ways of installing and operating such novel types of photobioreactors.

Microalgae use in animal nutrition

Looking for alternative sources in animal nutrition, microalgae began to be explored, gaining space in commercial production. The aim of this review is to present available information about the use of microalgae in animal nutrition, as well as its effect and applications. Many microalgae are important sources of polyunsaturated fatty acids (PUFA), mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These PUFA is poorly synthesized by animals, so they should be included in their diet. In addition, they are a rich source of almost all of the important minerals as well as vitamins. Additionally, some microalgae generally have a high protein content and high digestibility. In this context, microalgae already available on the market, become an alternative replacing conventional ingredients. To our knowledge, the use of small amounts of microalgae biomass in the feed can benefit the physiology of the animals, improving the immune response, resistance to diseases, antiviral and antibacterial action, intestinal function, and stimulation of probiotic colonization. In general, the addition of these compounds to the diets of animals enhances their overall health and immune status, productivity, and the quality and stability of the resulting animal products. Although the use of microalgae is increasingly directed towards many types of animals: cats, dogs, ornamental fish, horses, poultry, swine, sheep, and cow, studies still need to be explored.

Use of Microalgae Biomass for Fortification of Food Products from Grain

This article describes the use of Chlorella sorokiniana biomass additives in pasta recipes to enrich the product with biologically active phytonutrients, as well as to achieve the desired color range without the use of synthetic dyes. Samples of dry biomass were obtained by the cultivation of microalgae C. sorokiniana (strain), its quality indicators and nutritional value were determined for use as a food additive. A method of using dry biomass of microalgae C. sorokiniana as a phytoadditive to replace 5% of flour mixture for effective enrichment of pasta with biologically active phytonutrients was proposed. The choice of the optimal amount of addition of microalgae biomass was proved since it turned out that the replacement of flour should be no more than 5% due to the distinct fish flavor of the final product. The present study was conducted to evaluate the effect of adding dry biomass of Chlorella microalgae on total protein, lipid, chlorophyll, and carotenoid content. Substitution of 5% of pasta flour led to an increase in the content of proteins and lipids to 15.7 ± 0.50% and 4.1 ± 0.06%, respectively. Meanwhile, the addition of microalgae Chlorella to pasta has helped to increase the content of polyunsaturated fatty acids, chlorophyll, and carotenoids which are necessary for the prevention of foodborne diseases. The aim of this study is to develop pasta recipe with additives of microalgae biomass C. sorokiniana and study their quality indicators.