Amounts Of Polyunsaturated Fatty Acids Research Articles

Partial Replacement of Fishmeal with Seafood Discards for Juvenile Penaeus japonicus: Effects on Growth, Flesh Quality, Chemical and Fatty Acid Composition

The present study was designed to assess the influence of fishmeal replacement with increasing percentages of fresh seafood discards (0, 25, 50 and 75%) in diets for Penaeus japonicus on growth performance, physical characteristics and the chemical and fatty acid composition of shrimp flesh. Each diet was administered for 108 days, and the trial was assayed in triplicate. The final body weight and the specific growth rate were significantly higher (p < 0.05) in shrimps fed with 75% fishmeal replacement as compared to 25%, while the abdomen weight and the total length were the highest (p < 0.01). Moreover, 75% replacement showed a significantly (p < 0.05) lower value of hardness and a greater crude protein and lipid content as compared to the 0% replacement. The shrimps fed with high levels of seafood discards (50 and 75%) showed a lower saturated fatty acid concentration and, in turn, a greater amount of polyunsaturated fatty acids in shrimp meat significantly (p < 0.05) affected the lower atherogenic and thrombogenic indices. In conclusion, replacing 75% of fishmeal with seafood discards provided satisfactory results. An economic analysis based on ESG indicators and PESTLE methodology is provided in order to show the socio-economic and governance impacts affecting the replacement of shrimps’ diet with fish discard.

Characteristics of mountain vs. lowland dairy products

SummaryBesides the clean environment, mountain pastures are important sources of bioactive compounds that contribute to the quality of dairy products resulting from animals grazing there. This review aimed to compare the main differences among mountain and lowland dairies in terms of chemical composition, physical and sensory properties and microflora. The most important factors influencing final product properties are the biodiversity of pastures and the abundance of plants in terpenes and fatty acids, farm practices, animal breeds and climatic conditions. Differences between dairies from lowland and mountain products were observed regarding the sensory profile, microflora and nutritional and functional value. The comparisons of the results presented in the literature concluded that some mountain dairies presented more than 50% higher content of terpenes compared to lowland products. Furthermore, the amounts of polyunsaturated fatty acids (PUFA) were more than 15% greater in mountain products compared to lowland ones, conjugated linoleic acids more than 35%, n−6 and n−3 PUFA more than 10%, while the saturated fatty acids content was reported to be more than 3% lower in mountain dairies. In conclusion, mountain dairy products can be distinguished from lowland ones, especially by their content of terpenes and fatty acid profile, along with the microflora which are influenced by livestock management.

Investigation of Crypthecodinium cohnii High-Cell-Density Fed-Batch Cultivations

Crypthecodinium cohnii is a marine microalga that can accumulate high amounts of polyunsaturated fatty acids (PUFAs) and thus replace conventional routes of fish oil production. They are associated with the destruction of marine resources and multiple downstream/purification complications. The major drawbacks of using C. cohnii for industrial-scale production are associated with low PUFA productivity. One of the means of increasing the PUFA synthesis rate is to maintain the medium component concentrations at optimal values throughout cultivation, thus increasing PUFA production efficiency, which can result in the successful transfer of the process to pilot and/or industrial scale. The goal of the present research was to develop techniques for increasing the efficiency of PUFA production via C. cohnii cultivation. Multiple experiments were carried out to test and fine-tune the cultivation medium composition and oxygen transfer factors. The biomass yields from individual components, yeast extract, sea salts, and glucose amounted to 5.5, 0.65, and 0.61 g·g−1, respectively. C. cohnii cell susceptibility to mechanical damage was experimentally evaluated. Power inputs of <276.5 W/m3 did not seem to promote cell destruction when Pitched-blade impellers were used. The obtained cultivation conditions were shown to be efficient in terms of increasing the biomass productivity and the omega-3 fatty acid content in C. cohnii. By using the applied methods, the maximal biomass productivity reached 8.0 g·L−1·day−1, while the highest obtained biomass concentration reached 110 g·L−1. A steady increase in the concentration of PUFAs during cultivation was observed from the FTIR data.

Semaglutide Improves Liver Steatosis and De Novo Lipogenesis Markers in Obese and Type-2-Diabetic Mice with Metabolic-Dysfunction-Associated Steatotic Liver Disease.

Metabolic-dysfunction-associated steatotic liver disease (MASLD) is a prevalent clinical condition associated with elevated morbidity and mortality rates. Patients with MASLD treated with semaglutide, a glucagon-like peptide-1 receptor agonist, demonstrate improvement in terms of liver damage. However, the mechanisms underlaying this beneficial effect are not yet fully elucidated. We investigated the efficacy of semaglutide in halting MASLD progression using a genetic mouse model of diabesity. Leptin-receptor-deficient mice with obesity and diabetes (BKS db/db) were either untreated or administered with semaglutide for 11 weeks. Changes in food and water intake, body weight and glycemia were monitored throughout the study. Body fat composition was assessed by dual-energy X-ray absorptiometry. Upon sacrifice, serum biochemical parameters, liver morphology, lipidomic profile and liver-lipid-related pathways were evaluated. The semaglutide-treated mice exhibited lower levels of glycemia, body weight, serum markers of liver dysfunction and total and percentage of fat mass compared to untreated db/db mice without a significant reduction in food intake. Histologically, semaglutide reduced hepatic steatosis, hepatocellular ballooning and intrahepatic triglycerides. Furthermore, the treatment ameliorated the hepatic expression of de novo lipogenesis markers and modified lipid composition by increasing the amount of polyunsaturated fatty acids. The administration of semaglutide to leptin-receptor-deficient, hyperphagic and diabetic mice resulted in the amelioration of MASLD, likely independently of daily caloric intake, suggesting a direct effect of semaglutide on the liver through modulation of the lipid profile.

INFLUENCE OF LOW-INTENSITY LIGHT ON THE BIOSYNTHETIC ACTIVITY OF THE MEDICINAL MACROMYCETE LARICIFOMES OFFICINALIS Laricifomes officinalis (Fomitopsidaceae, Polyporales) in vitro

Understanding the impact of artificial lighting on the biosynthetic and biological activity of medicinal mushrooms will help enhance technologies aimed at obtaining bioactive compounds. The aim of our work was to determine the influence of low-intensity quasi-monochromatic light on biosynthetic activity, including the antioxidant activity of the medicinal fungus Laricifomes officinalis under submerged cultivation conditions. Methods. The effect of light on the biosynthetic activity of L. officinalis was studied using sources of low-intensity coherent monochromatic laser light and quasi-monochromatic radiation of light-emitting diodes (LEDs) with specified spectral-intensity characteristics. Results. The most stimulating effect on the biosynthetic activity of the L. officinalis strain was observed when samples were irradiated with blue (488 nm laser and 470 nm LED) and red (650 nm LED) light. Under these conditions, there was an increase in the synthesis of mycelial mass, polysaccharides, and the quantity of total phenolic compounds. Low-intensity light irradiation caused changes in both the quantitative and qualitative composition of the fatty acid profile of the mycelial mass. Red light irradiation resulted in an increase in the quantity of polyunsaturated fatty acids. A correlation was established between the quantity of total phenolic compounds and antioxidant activity. Conclusions: The research results provide grounds to consider low-intensity visible light as a promising regulator of the biosynthetic activity of L. officinalis in the biotechnology of its cultivation.

Effects of nitrogen starvation on growth and biochemical composition of some microalgae species.

Nitrogen is one of the most important nutrient sources for the growth of microalgae. We studied the effects of nitrogen starvation on the growth responses, biochemical composition, and fatty acid profile of Dunaliella tertiolecta, Phaeodactylum tricornutum, and Nannochloropsis oculata. The lack of nitrogen caused changes in carbohydrate, protein, lipid, and fatty acid composition in all examined microalgae. The carbohydrate content increased 59% in D. tertiolecta, while the lipid level increased 139% in P. tricornutum under nitrogen stress conditions compared to the control groups. Nitrogen starvation increased the oligosaccharide and polysaccharide contents of D. tertiolecta 4.1-fold and 3.6-fold, respectively. Furthermore, triacylglycerol (TAG) levels in N. oculata and P. tricornutum increased 2.3-fold and 7.4-fold, respectively. The dramatic increase in the amount of TAG is important for the use of these microalgae as raw materials in biodiesel. Nitrogen starvation increased the amounts of oligosaccharides and polysaccharides of D. tertiolecta, while increased eicosapentaenoic acid (EPA) in N. oculata and docosahexaenoic acid (DHA) content in P. tricornutum. The amount of polyunsaturated fatty acids (PUFAs), EPA, DHA, oligosaccharides, and polysaccharides in microalgal species can be increased without using the too costly nitrogen source in the culture conditions, which can reduce the most costly of living feeding.

Variations in Chlorella lipid content in commercial and in-lab produced biomass

Microalgae appear as a sustainable source of biomass with relevant nutritional qualities. Still, regulatory restrictions currently limit the use of eukaryotic microalgae for human consumption to a short list of species dominated by Chlorella spp. Chlorella biomass contains valuable proteins but also interesting lipids, including polyunsaturated fatty acids (PUFA) ω3 and ω6. The amount of PUFA and the ω6/ω3 ratio vary significantly depending on the species and cultivation trophic mode. While the lipid profils of in-lab produced Chlorella has been widely studied, the variability of lipid content in commercial biomasses is barely described. Here, lipid classes and fatty acid profiles of six commercial biomasses of Chlorella spp. as well as those of lab-produced C. sorokiniana grown in photo-autotrophy and in four mixotrophy conditions were characterized. Results showed significant lipid composition variations between the biomasses, such as the triacylglycerols/glycolipids and ω6/ω3 contents. The ω6/ω3 ratios were lower in photo-autotrophic mode (2.5) while they ranged between 1.3 and 8.9 in commercial biomasses. The free fatty acids level was also variable (1.4% to 17.9% of total lipids). As a consequence, Chlorella lipid content and quality differed significantly, impacting the potential nutritional benefits of the consumption of commercial biomass. Processing and post-processing conditions should therefore be carefully controlled to optimize lipid profiles.

Rosehip oil nanoemulsion as a stable delivery system for omega-3 fatty acids to enhance the nutritional value of yogurt

Rosehip oil (REO) contains excessive amounts of polyunsaturated fatty acids (PUFA), such as Omega-3 fatty acids (OFA). OFA exhibits instability, poor solubility, and limited bioavailability upon addition to food. In this study, REO nanoemulsion was prepared by probe ultrasonication. Statistically designed experiments were used to optimize Ultrasonication time (5 min), ultrasonication amplitude (37.26 %), and the surfactant (1 %Tween 20) concentration (surfactant to oil ratio of 1.17:1). The spherical morphology of the nanoemulsion was studied using scanning electron microscopy. REO was further characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) spectroscopy. The droplet size of REO nanoemulsion increased from 60 to 88 nm during storage at 4 ⁰C for 28 days. The nanoemulsion had an encapsulation efficiency of 89.7 %, and it was stable based on thermodynamical study. The fatty acid profile confirmed that REO nanoemulsion could preserve linoleic acid compared to the direct addition of REO in yogurt. The sensory study revealed that REO nanoemulsion could mask the tartness of REO when incorporated into yogurt. This study proved that nanoemulsion is a potential tool to enhance the stability of OFA in food systems.

Nutritive and Anti-Nutritive Compounds of Oil Seeds Renewables and By-Products in the Livestock Industry

Nigeria is one of the major oilseeds producers in Africa due to favorable climatic and edaphic factors. They strive well under rain-fed conditions; under low rainfall the crops experience moisture stress causing low yield. Oil seeds have recently attracted more interest due to their nutritional composition and the demand keeps rising due to the increase in population growth. Oil seed products such as soybeans, cottonseed, rapeseed, sunflower, and camelina meal or cake are sources of amino acids, and digestible rumen protein and minerals that influence animal growth and development. Due to the considerable amount of polyunsaturated fatty acids, it causes toxins accumulation and inflammation. The presence of antinutrients such as glucosinolates, trypsin inhibitors, gossypol, and lectins in these oilseeds inhibits their protein degradability, mineral bioavailability, flavor, and taste. Animals are affected by the toxicity of antinutrients leading to diseases and death. Glucosinolates, trypsin inhibitors, are known to reduce feed intake and cause iodine deficiency causing goiter and enlargement of the liver, kidney, and thyroid of animals which consequently affects the body. This paper summarizes the nutritive and anti-nutritive values of different oil seeds, the effect of different livestock animals, and the methods of reducing or eliminating the attributive compounds.

Nutritional Composition and Odor-Contributing Volatile Compounds of the Edible Mushroom Cantharellus alborufescens.

Chanterelles are one of the most highly valued wild edible mushroom genera worldwide. This work aimed to investigate the nutritional characteristics and volatile compounds' profile of Cantharellus alborufescens for the first time. Proximate analysis was performed according to the Association of Official Agricultural Chemists, while the mineral contents and the volatile compounds were determined using ICP-MS and GC-MS, respectively. C. alborufescens had an average of 25.8% protein, 5.5% fat, 12.7% ash, and 55.9% carbohydrates, including 11.4% fiber per dw of mushroom. Further analyses of the fat and protein contents revealed high amounts of polyunsaturated fatty acids as well as monosodium glutamate-like amino acids. Linoleic acid (42.0% of fat) and oleic acid (28.6% of fat) were the major fatty acids, while leucine (1.2%) and lysine (0.9%) were the most abundant essential amino acids. The results showed that C. alborufescens contained 3.1 µg/g vitamin D2 and 4.9 mg/g vitamin E per dw, as well as notable quantities of macro- and microelements, such as potassium, calcium, magnesium, and iron. GC-MS analysis revealed various volatile compounds such as acetaldehyde, n-hexanal, 3-methylbutanal, 1-octen-3-ol, etc. In conclusion, this study supports the use of C. alborufescens as a food rich in fiber and vitamin E, with a suitable amount of protein and other nutrients.

Flaxseed (Linum usitatissimum) low temperature processing: Oil quality and fatty acids profile

Flaxseed consumption has been prioritized by health-conscious people all over the world. Its consumption raises interest to it both from a personal and an industrial prospect due to its remarkable fatty acids profile. Besides its high content of unsaturated fatty acids, flaxseed oil is known for its low omega 6/omega 3 ratio, which may possess health improving properties because this oil is precursor of anti-inflammatory molecules. However, the high amount of polyunsaturated fatty acids in flaxseed oil causes its high sensitivity to high temperatures, to light and to oxygen, which may lead to its oxidation and quality degradation. Screw pressing can produce high quality oil but in lesser volume, which could be disadvantage. Therefore, the extraction process must be optimized for maximizing oil recovery, while maintaining oxidation indicators within limits specified by regulations, as well as a potentially health beneficial fatty acid profile. Optimization of screw press parameters for pressing out the flaxseed oil were investigated by Response Surface Methodology. Both size of the cake outlet and the speed of the screw pressing were optimized, and the values that provided the highest experimental oil recovery, 41.4%, were of 1 mm and 155.89 rpm respectively. Although the overall trend in oil extraction showed a rising oil recovery when screw speeds increased from 98.73 up to 213.05 rpm, certain fluctuations were observed in oil extraction with varying outlet cake sizes. However, there was an inversely-proportional function between the oil recovery and the size of the cake outlet, therefore, screw speed provided a minor, non-significant effect while the size of the cake outlet proved to have a strong effect on oil recovery. The highest acid value and peroxide value accounted to 0.71 mg KOH/g and to 7.71 meq/kg respectively. Sediment content (SC) of screw pressed flax oil ranged between 9.12~14%. During the oil extraction at the maximum yield, temperature increased, however the ratio of omega 6 to omega 3 in the obtained oil still remained low.

Mixotrophic Cultivation of Chlorella vulgaris on Banana Waste for Biodiesel Production

Environmentally friendly biofuels are currently produced in large quantities using algal lipids. Objective: To perform mixotrophic cultivation of Chlorella vulgaris on Banana Waste for Biodiesel Production. Methods: Banana waste was treated with acid/alkaline, ground, and sun dried. The resultant hydrolysate was used into studies comparing photoautotrophic and mixotrophic conditions in microalgae culture. When biomass productivity and lipid content were measured. For mono-unsaturated, poly-unsaturated, and saturated forms, the lipid content differed. The research used analytical methods for fatty acid methyl ester analysis, such as GC-MS. Results: Mixotrophic cultivation exhibited a much higher biomass productivity (135 mg L-1 d-1) than photoautotrophic cultivation (115 mg L-1 d-1). Additionally, mixotrophically raised biomass had a much larger (w/w) lipid content (45%) than photo-autotrophically raised biomass (30 %). Higher amount of polyunsaturated fatty acids (palmitic and oleic acids) was shown by Lipidome. Conclusions: High-quality biofuel might be made possible by the regular availability of polyunsaturated fatty acids (64 mg g-1 of dry biomass) in the lipid contents of mixotrophically produced algal biomass

Diets with soybean oil and l-carnitine alter lipid metabolism and improve the growth and reproduction of Rhamdia quelen females

This study aimed to evaluate the reproduction, growth, biochemical parameters of blood, hepatic and gonadal redox parameters, hepatic and gonadal histology, and lipid metabolism of silver catfish females (Rhamdia quelen) fed diets containing l-carnitine and different lipid sources. Females were fed for 223 days with eight (08) isoproteic (282 g of digestible protein kg of ration−1) and isoenergetic (13.34 MJ of digestible energy kg of ration−1) diets, containing 0.00, 0.15, 0.45, and 0.75 g l-carnitine kg−1 of feed, and soybean or marine fish oils. Feeding the females diets containing l-carnitine and the different oils resulted in an interactive effect (p < 0.05) that improved the growth and reproduction of the fish. Females fed soybean oil and 0.45 g l-carnitine kg−1 had the highest growth rates, the largest ovaries, and produced the most fertile oocytes, which resulted in the highest hatching rates. These females also showed higher levels of total cholesterol and high-density lipoprotein (HDL) cholesterol, and alterations in the levels of alanine aminotransferase in the blood, in addition to greater activity of hepatic superoxide dismutase and a greater amount of saturated fatty acids in the liver. The ovaries of these females also had the highest amount of docosahexaenoic fatty acid (DHA), highest amount of polyunsaturated fatty acids and fatty acids from the n-3 and n-6 series, and the lowest crude protein content. The interaction between l-carnitine and the lipid source of the diets promoted hepatic protection and regulated lipid metabolism and the fatty acid profile in the liver and ovaries of silver catfish females. The benefits of these interactions improved the growth and reproduction of females fed diets containing soybean oil and 0.45 g l-carnitine kg−1.

Effect of Germination on Fatty Acid Composition in Cereal Grains.

Sprouted grains are gaining popularity as functional food ingredients. This study aimed to evaluate the lipid and fatty acid composition of eight sprouted grains (millet, amaranth, quinoa, wheat, rye, barley, buckwheat, and oat). The method used was germination for up to 72 h at temperatures ranging from 19-23 °C. In general, the lipid content increased in the various grains sprouted, providing a rich source of polyunsaturated fatty acids. The % oil yield ranged from 1.17 ± 0.02% in sprouted rye to 5.71 ± 0.26% in sprouted amaranth. Germinated oat showed the greatest increase in fat content, 54.3%, compared to the control. Polyunsaturated fatty acids were more prevalent in whole grains (46.9-75.6%) than saturated fatty acids (10.1-25.9%) and increased with sprouting. The primary fatty acids detected in the grains, in order of abundance, were linoleic, oleic, palmitic, linolenic, and stearic acids. Millet sprouts contained the lowest total saturated fatty acids and the highest polyunsaturated fatty acids. Amaranth had the highest amount of saturated fatty acids, while buckwheat contained the lowest quantity of polyunsaturated fatty acids. The lowest omega-6/omega-3 ratio was 7 to 1 in sprouted rye and 8 to 1 in sprouted barley.

Seasonal changes in fatty acid profile of the freshwater snail Viviparus contectus (Millet, 1813) from lake habitat

ABSTRACT The freshwater snail, Viviparus contectus, is an important shellfish owing to its nutritional composition (i.e., high amounts of protein, essential amino acids, fatty acid profile and minerals) and its promise as a candidate for the treatment of some diseases in traditional medicine. Hence, the seasonal changes in the fatty acid (FA) profile of Viviparus contectus caught from Demirköprü Dam Lake were determined in this study. Saturated fatty acid (SFAs) (64.54–80.39% of total fatty acids) had the highest concentration followed by polyunsaturated fatty acids (PUFAs) (10.63–21.83%) and monounsaturated fatty acids (MUFAs) (6.57–10.13%). Stearic acid (C18:0) was the major SFA while arachidonic acid (C20:4 n−6) was the major PUFA. The season significantly affected the FA profile of V. contectus while no significant difference was determined between seasons with respect to tissue MUFAs levels. A higher level of total SFAs was detected during spring (80.39%) while a higher proportion of MUFAs was detected during the winter (10.13%). The total amounts of PUFAs were highest in winter (21.83%). Overall, V. contectus has nutritional value. However, V. contectus caught in autumn may be nutritionally the most valuable for human consumption due to higher eicosapentaenoic acid 20:5 n−3 and docosahexaenoic acid contents.

Development and characterization of omega-3-rich flaxseed oil microcapsules and evaluation of its stability and release behavior in probiotic millet yogurt

The study investigated the encapsulation potential of probiotics (PRO) and flaxseed oil (FS) using different wall materials, including sodium alginate-maltodextrin-inulin (SIN), skim milk (SK), whey protein (WP), and soy protein concentrate (SP) to produce oil-enriched millet yogurt. The microcapsules (SIN-FS-SK, SIN-FS-WP, and SIN-FS-SP) and co-microcapsules (SIN-FS-PRO-SK, SIN-FS-PRO-WP, and SIN-FS-PRO-SP) were characterized by encapsulation efficiency, lipid oxidation, FTIR, SEM, and GC–MS. Thus, the obtained emulsion droplets size was favorable (1.11 to 1.73 μm) for freeze-drying with an encapsulation rate above 95%, better oxidative stability at 4 °C, and microcapsule sizes between 800 and 1600 μm allowing the oil release during intestinal stage (51–65%). Thus, it was possible to obtain flaxseed oil enriched-millet yogurt with good oxidative stability. Adding co-microcapsules also improved the quantities of polyunsaturated fatty acids (PUFAs), particularly alpha-linolenic acid, in the various products, enabling a significant release of PUFAs during intestinal digestion, thus improving the omega 6/omega 3 ratio.

The effects of dietary inclusion of Camelina sativa on performance and ascites incidence in broilers subjected to cold exposure.

Camelina sativa oilseed has a high amount of polyunsaturated fatty acids (FAs) especially α-linolenic acid. n-3 FA can improve the deformability of erythrocytes and mediate relaxations in coronary artery such as nitric oxide (NO) that is the principal vasodilator responsible for diminution the pulmonary arterial hypertension response. To investigate the effects of camelina sources on ascites incidence in broilers kept on altitude, 672 male chicks were fed with 7 dietary treatments, including control, 2% or 4% camelina oil (CO), 5% or 10% camelina meal (CM) and 5% or 10% camelina seeds (CS) diets. Supplementation of 2% CO had no negative impact on performance, whereas feed intake and body weight gains decreased (p<0.05) by adding 4% CO, CM and CS. Birds fed camelina diets had lower serum triglyceride at day 42, total cholesterol and LDL cholesterol at both 28 and 42 days. Plasma aspartate aminotransferase decreased (p<0.001) among 5% and 10% CS groups on day 42. Serum and liver concentrations of malondialdehyde declined (p<0.05) by camelina treatments, whereas serum NO and liver glutathione peroxidase activity significantly elevated. Red blood cell, heterophils and H:L ratio were lower but lymphocyte was higher in camelina groups. Inclusion of camelina reduced (p<0.05) relative weights of heart and right ventricle, the weight of right ventricle to total ventricle ratio and ascites mortality. Use of 2% CO as a source of n-3 FA can improve ascites condition and mortality in broilers reared at high altitude without the reduction of growth performance. However, feeding 4% CO or 5% and 10% CS or CM reduced broiler performance.

Evidence of the drying technique’s impact on the biomass quality of Tetraselmis subcordiformis (Chlorophyceae)

Rapid drying, cost-effective and safe, will increase the viability of using microalgae for several bio-industrial applications. In this study, five different drying techniques of microalgal biomass were investigated. These include freeze drying, oven drying, air drying, sun drying, and microwave drying. Morphology, metabolite content, FAME profiling, chlorophyll content, total organic carbon, and total nitrogen were analyzed. Results showed that the freeze-drying technique preserves the highest amounts of chlorophyll, proteins, and lipids. Oven drying underperformed as it retained the lowest amount of chlorophyll, protein, and lipid content. More importantly, FAME profiling results showed that air drying was the best technique in maintaining the highest amount of polyunsaturated fatty acids and more specifically docosahexaenoic acid (DHA). Furthermore, this process requires the least capital and energy needs. The findings from this study confirmed that the drying technique affects the microalga biomass quality.Graphical

Biotechnological product potential of Auxenochlorella protothecoides including biologically active compounds (BACs) under nitrogen stress conditions.

Nitrogen stress can influence microalgae's growth characteristics, and microalgae grown in nitrogen-deficient conditions may produce higher or lower levels of biotechnological products as a result of metabolic changes. In photoautotrophic and heterotrophic cultures, nitrogen limitation has been proven effective in promoting lipid accumulation. In spite of this, no study has demonstrated a significant correlation between lipid content and other biotechnological products such as bioactive compounds (BACs).This research examines a strategy for lipid accumulation as well as the potential production of BACs with antibacterial properties in parallel with that strategy. This concept involved the treatment of the microalga Auxenochlorella protothecoides with low and high concentrations of ammonium (NH4+). This particular experiment reached a maximum lipid content of 59.5% using a 0.8 mM NH4+ concentration, resulting in the yellowing of the chlorophyll levels. Agar diffusion assays were conducted to determine the antibacterial activity of different extracts derived from the biomass when stressed with different levels of nitrogen.Algal extracts prepared by a variety of solvents showed different levels of antibacterial activity against representative strains of both gram-negative (Escherichia coli) and gram-positive (Staphylococcus aureus) bacteria. Among the extracts tested, 500mg/L ethyl acetate extract had the greatest antibacterial activity against Escherichia coli. In order to identify the components responsible for the extract's antibacterial activity, fatty acid methyl ester (FAME) analysis was performed. It has been suggested that the lipid fraction may be a valuable indicator of these activities since some lipid components are known to possess antimicrobial properties. In this regard, it was found that the amount of polyunsaturated fatty acid (PUFA) significantly decreased by 53.4% under the conditions with the highest antibacterial activity observed.

Effects of Polyunsaturated Fatty Acids on Human Health Through Intestinal Microbiota

Unsaturated fatty acids act a necessary part in the intestinal health of the host microbiota environment and immune ability by being transformed by intestinal microorganisms. Polyunsaturated fatty acids (PUFAs) are very important to the host body, also they influence many physiological activities of the body. The amount of polyunsaturated fatty acids synthesized by the human body cannot meet the daily needs of the human body, and it is necessary to obtain some essential fatty acids (EFA) from food. At the same time, some intestinal microorganisms can also synthesize and convert polyunsaturated fatty acids, which contribute to the regulation and control of host immunity. In addition, PUFAs are also beneficial to humans. They are critical in sustaining a healthy and stable gut microbiota environment and regulating and controlling host immunity. This paper summarized the conversion mechanism and effect of intestinal microbiota on polyunsaturated fatty acids, discussed whether polyunsaturated fatty acids can regulate human diseases and microbiota as health products, and determined the regulatory mechanism of polyunsaturated fatty acids.