Certain microalgae species have gained traction in the biofuel and food/feed sectors due to their ability to accumulate large amounts of intracellular lipids. However, the extraction of lipids from microalgae is hindered by the presence of complex and recalcitrant cell walls that act as a barrier to mass transfer. This paper examines the intricate details of microalgae cell walls of species belonging to three genera—Nannochloropsis, Scenedesmus, and Schizochytrium—known for their high total lipid contents and omega-3 polyunsaturated fatty acid contents, thus having dual potential for both biofuel and food/feed application. An overview of the techniques used to analyse the cell walls, followed by a detailed description of the cell wall architecture of the three genera and the growth conditions that affect the ultrastructure and composition of their cell walls, is presented. Since cell wall disruption is a crucial step in recovering intracellular products from microalgae biomass, different cell-disruption technologies are also reviewed, focusing specifically on approaches that can be applied directly to wet biomass without the need for biomass drying, thus exerting a low-energy footprint. Enzymatic treatment is operated under mild conditions and offers a promising wet route for targeted recovery of intracellular products from microalgae with minimal side reactions and risk of product degradation. The high cost of enzymes can be mitigated by reducing enzyme requirements through the adoption of a minimal design approach that uses the cell wall composition as the basis to direct enzyme choice and dosage. Different enzyme-recycling and immobilisation strategies to reduce enzyme requirements and improve commercial scalability are also reviewed. Finally, the paper provides a summary of the current state-of-the-art in direct biological approaches using algicidal bacteria and fungi to achieve cell disruption. Overall, the paper provides a roadmap for a more efficient cell disruption of microalgae.

Background/Objectives: Microalgae are gaining increasing attention as sustainable sources of dietary lipids and other bioactive compounds; however, the relationship between microalgae lipid composition and physiological outcomes in vivo remains insufficiently understood. This study aimed to characterize antioxidant activity, total lipid content and fatty acid (FA) profiles of selected freshwater microalgae and to evaluate their dietary impact using Drosophila melanogaster as a whole-organism model. Methods: Four freshwater microalgal species (Chlorella vulgaris, Nannochloris limnetica, Scenedesmus communis, and Tetradesmus obliquus) were cultivated separately in 3N-BBM+V medium under controlled laboratory conditions. DPPH, FRAP and TPC were measured in microalgae methanolic extracts. Total lipids were extracted using a modified Breuer method and quantified gravimetrically. FA profiles were determined as fatty acid methyl esters by GC-FID. Freeze-dried microalgal biomass (3 mg/mL) was incorporated into standard D. melanogaster diet. Lifespan and body mass were assessed separately in females and males, as well as fecundity in general. Results: Total lipid content ranged from 17.3% to 28.1% of dry weight, with FA profiles dominated by C16 saturated, monounsaturated (omega-9), and omega-6 polyunsaturated fatty acids. Correlation analysis indicates that antioxidant properties of the studied microalgae are more closely linked to lipid fractions than to phenolic content. Dietary supplementation with microalgal biomass of three out of four microalgal species significantly extended median lifespan, particularly in males, without adverse effects on body mass or fecundity. Conclusions: These findings indicate that freshwater microalgae can serve as a physiologically safe dietary lipid source. D. melanogaster represents a suitable in vivo model for screening the nutritional potential of microalgal lipids.

Hepatitis C is a viral liver disease caused by HCV. Worldwide, 71 million people suffer from chronic hepatitis C infection. There is a discussion in the literature sources about the association of blood groups of the AB0 system with viral hepatitis; however, the data obtained in different populations of high rank is controversial. The aim of the study was to investigate possible associations of blood groups of the AB0 system with hepatitis C in the Odessa region. The case-control study was conducted in 2017–2019 at the blood transfusion station of SE «Odessa Railway». The control group consisted of 18 963 healthy individuals, the experimental group consisted of 520 people from the donors examined, in which blood antibodies to HCV were detected. Determination of blood groups was performed according to the standard method, serological studies – ELISA on ELISA analyzer III. The analysis using the χ2 criterion showed that the frequencies of blood groups in the control and experimental groups differed significantly (p ≤ 0.005). To determine the effects of each blood group, relative risk frequencies for each blood group were calculated. People with the AB blood group had the lowest risk of infection (OR = 0.60), with a slightly weaker negative association observed among people with blood group 0 (OR = 0.86). Individuals with blood groups A and B had a positive association; the rate of infection of persons with blood group B was the highest (OR = 1.23). The findings complement a diverse picture of such associations in different populations. The variation in associations in different populations may be due to both statistical causes and genetic diversity of human and HCV populations, as well as the interaction between human immunity-related genetic systems. The existence of associations between the AB0 system and susceptibility/immunity to hepatitis C may be an additional indicator of the assessment of risk groups, which is functional for certain populations in certain sanitary and epidemiological conditions.

Microalgae are seen as a promising source of sustainable essential lipids for animal and human nutrition. These advantages, however, differ depending on the strain and growing conditions. Furthermore, the link between microalgae lipid profile and their effect on target organisms during dietary consumption is still not well understood. This study examined the lipid content and antioxidant properties of four microalgae strains cultured on 3N-BBM+V medium, and the effect of their dietary inclusions on the lifespan, body mass, and fertility of the common fruit fly Drosophila melanogaster. It was shown that C. vulgaris, N. limnetica, S. communis, T. obliquus exhibit total lipids at 26.7 ± 2.8%, 27.2 ± 0.9%, 16.6 ± 3.0%, and 22.6 ± 0.9% of dry biomass, respectively. All microalgal species produced unsaturated C15:0, C16:0, monosaturated C18:2n6 (omega-6), and C18:1n9 (omega-9) but at different proportions. Feeding D. melanogaster with C. vulgaris, S. communis, or T. obliquus biomass at 3 mg/mL inclusion extended the female median lifespan by 45.9%, 8.1%, and 27.0%, respectively. A more significant extension was observed for fly males, where adding biomass of C. vulgaris, N. limnetica, S. communis, and T. obliquus increased the lifespan of the flies by up to 75.0%, 25%, 29.2% and 50.0% re-spectively. The fertility of flies fed with T. obliquus and S. communis was also increased by 20% and 18% respectively. Meanwhile, no significant difference in the body mass of flies fed with microalgae was detected compared to the control.

Basidial macromycetes may be a material for the development of new biotechnologies, medical preparations, components of dietary nutrition. Therefore, it is necessary for the highest level of quality for maintenance and identification of mushroom strains in the collection. An important parameter, in this case, is a stability of isolated and described collection strains of basidiomycetes. Stability is one of the key issues of long-term preservation of pure culture collections. For the collection of medicinal basidiomycetes of ONU I.I. Mechnikov, which preserves by the method of periodic reseeding of colonies the strain stability had not been studied yet. The goal of this research is to study the stability of this collection by a growth rate of mushroom colonies and electrophoretic spectra of carboxylesterases after different times of storage of cultures on malt agar. In this research the strains of three age categories (1, 2 and 3 years) of storage on malt-agar medium at temperature 4 ° С for were tested. The radial growth rate of their vegetative mycelium and the spectra of multiple molecular forms of carboxylesterases by the method of vertical electrophoresis in 7% of polyacrylamide gel were investigated. It was established that the stability of the radial growth rate of A. auricula-judae, F. velutipes, G. lucidum the vegetative mycelium after different storage periods is high according to the values of variation coefficients. At the same time, the expression of molecular forms of carboxylesterase showed sufficient variability. Partially conservative molecular forms were detected in some age groups of strains, as well as for individual strains. Thus the growth rate of colonies is a stable indicator and the molecular forms of carboxylesterases of different ages strains are variable.