Higher Docosahexaenoic Acid Research Articles

Dietary DHA Regulated the Androgen Production in Male Chinese Tongue Sole Cynoglossus semilaevis

Long‐chain polyunsaturated fatty acids (LC‐PUFA) play key roles in sex steroid hormone synthesis in fish. Regarding docosahexaenoic acid (DHA), currently the regulating effects were mostly evaluated in female fish rather than males. This study aimed to investigate the DHA effects on the sex steroid hormone production in male Chinese tongue sole. Three experimental diets were prepared, containing different DHA levels: a control (C) group (5.16% DHA of total fatty acids [TFA]), a low DHA group (DHA‐L, 8.93%), and a high DHA group (DHA‐H, 16.47%). A 58‐day feeding experiment was conducted, and each diet was fed to triplicate tanks of fish. Additionally, an in vitro study with Leydig’s cells of this species was conducted to validate the in vivo results. The concentration of testosterone (T) and 11‐ketotestosterone (11‐KT) in the serum increased with increasing levels of dietary DHA. Dietary DHA significantly upregulated the expression of steroid hormone biosynthetic genes p450c17, hsd17b1, hsd3b1, aromatase, hsd11b2, and p45011b in the testis. The protein expression of Hsd17b1 in the testis of the DHA‐H group was significantly higher compared to the other two groups, while the expression level of P450c17 showed an increasing trend with increasing dietary DHA levels. However, the in vitro results confirmed that the final concentration of DHA at 50 μmol/L could significantly increase the gene expression of p450c17 in Leydig’s cells. In conclusion, dietary DHA may promote the synthesis of T and 11‐KT through the regulation of protein (Hsd17b1 and P450c17) and gene (p450c17, hsd17b1, hsd3b1, aromatase, hsd11b2, and p45011b) expression of a series of key steroid hormone biosynthetic enzymes in male Chinese tongue sole.

Enzymatic Interesterification of Cold-Pressed Maqui (Aristotelia chilensis (Mol.) Stuntz) Seed Oil and Belly Oil from Rainbow Trout (Oncorhynchus mykiss) Through Supercritical CO2.

A new antioxidant lipid (AL) was synthesized from rainbow trout (Oncorhynchus mykiss) belly oil and cold-pressed maqui (CPM) (Aristotelia chilensis (Mol.) Stuntz) seed oil via enzymatic interesterification using Thermomyces lanuginosus in supercritical CO2 medium. A Box-Behnken design with 15 experiments was employed, with the independent variables being the following: belly oil/CPM oil ratio (10/90, 50/50, and 90/10, w/w), supercritical CO2 temperature (40.0, 50.0, and 60.0 °C), and supercritical CO2 pressure (100.0, 200.0, and 300.0 bar) for enzymatic interesterification. A multiple optimization was conducted based on the response variables yield and eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and tocopherol contents. The optimized conditions for the AL synthesis were: 81.4/18.6 (w/w), 40.0 °C and 299.99 bar, respectively. The corresponding responses variables were: 77.10% for yield, 5.12 and 4.95 g·100 g-1 total fatty acids for EPA and DHA, respectively, and 217.96, 4.28, 3.48, 64.48, and 6.39 mg·kg-1 oil for α-tocopherol, α-tocotrienol, β-tocopherol, γ-tocopherol, and δ-tocopherol, respectively. A novel AL was successfully synthesized starting from two abundant natural resources commonly considered as by-products during industrial processing. In agreement with the high EPA, DHA, and tocopherol presence, this AL can be recommended to be employed in nutritional and therapeutic supplements, according to its health benefits, particularly concerning antioxidant and anti-inflammatory properties.

Influence of the Degree of Unsaturation in Fish Oil Supplements on Oxidative Stress and Protein Carbonylation in the Cerebral Cortex and Cerebellum of Healthy Rats.

ω-3 polyunsaturated fatty acids (PUFAs) are crucial for brain structure and function, especially docosahexaenoic acid (DHA). However, an excess of DHA may increase lipid peroxidation due to its high degree of unsaturation, particularly in tissues highly susceptible to oxidative stress, such as the brain. Therefore, this study evaluated the effects of 10 weeks of dietary supplementation with fish oil containing 80% DHA on oxidative stress and the modulation of the carbonylated proteome in both the cerebral cortex and cerebellum of male Sprague Dawley rats. The results were compared with those induced by oils with a lower degree of fat unsaturation (fish oil containing 25% DHA and 25% eicosapentaenoic acid, soybean oil containing 50% linoleic acid and coconut oil containing 90% saturated fat). The results demonstrated that fish oil containing 80% DHA significantly increased the ω3/ω6 ratio in both the cortex and cerebellum while stimulating antioxidant defense by enhancing the reduced glutathione amount and decreasing the carbonylation of specific proteins, mainly those involved in glycolysis and neurotransmission. The majority of sensitive proteins in both brain regions followed this carbonylation trend (in decreasing order): soybean > EPA/DHA 1:1 > coconut > 80% DHA. The results also indicated that the cerebellum is more responsive than the cortex to changes in the cellular redox environment induced by varying degrees of fat unsaturation. In conclusion, under healthy conditions, dietary supplementation with fish oils containing high DHA levels makes the brain more resilient to potential oxidative insults compared to oils with lower DHA content and a lower degree of fatty acid unsaturation.

Investigating the availability of omega-3 fatty acid from different sources and its effect on table eggs

The impact of three different commercial omega-3 fortifying agents on the growth performance, egg weight, egg production, and omega-3 fatty acid enrichment of white table eggs in layers was investigated. The experiment involved 12,000-layer birds randomly divided into four groups, with each group replicated three times and consisting of 1000 birds per replicate. The three groups, namely LP, AG, and DD, were supplemented with omega-3 fortifying agents LinPro, All-G-Rich, and DHA-gold, respectively, while the fourth group NC served as a negative control without omega-3 fortifying agent supplementation. The experiment commenced after the 25th week of age and lasted for a period of four weeks in a completely randomized design. Egg weight and egg production were recorded weekly, while the omega-3 fatty acid content of the white eggs was determined at the end of the 30-day trial after the 25th week of age. The supplementation of different omega-3 fortifying agents significantly impacted feed intake, with notable differences observed among weekly and overall means. Birds supplemented with LinPro consumed less feed during the 2nd and 4th week of the trial compared to the control, resulting in an overall reduction of 1.1 g/chick in feed intake. However, supplementation did not significantly affect the body weight of layers throughout the trial, nor did it impact egg weight or production. Nevertheless, the omega-3 fortifying agents had a significant effect on the omega-3 fatty acid content of the white table eggs in layers. LinPro supplementation notably increased α-linolenic acid (18:3; ALA) and eicosapentaenoic acid (20:5; EPA) levels, while DHA-Gold resulted in the highest docosahexaenoic acid (22:6; DHA) content. Total fatty acid content was highest in eggs from layers supplemented with LinPro, followed by DHA-Gold and All-G-Rich, with the lowest levels observed in the control group. These findings suggest that dietary supplementation of LinPro in layer diets post the 25th week of age could effectively enhance the omega-3 fatty acid content of white table eggs without compromising feed intake, body weight, egg weight, or egg production.

Effects of aeration and centrifugation conditions on omega-3 fatty acid production by the mixotrophic dinoflagellate Gymnodinium smaydae in a semi-continuous cultivation system on a pilot scale

High production and efficient harvesting of microalgae containing high omega-3 levels are critical concerns for industrial use. Aeration can elevate production of some microalgae by providing CO2 and O2. However, it may lower the production of others by generating shear stress, causing severe cell damage. The mixotrophic dinoflagellate Gymnodinium smaydae is a new, promising microalga for omega-3 fatty acid production owing to its high docosahexaenoic acid content, and determining optimal conditions and methods for high omega-3 fatty acid production and efficient harvest using G. smaydae is crucial for its commercial utilization. Therefore, to determine whether continuous aeration is required, we measured densities of G. smaydae and the dinoflagellate prey Heterocapsa rotundata in a 100-L semi-continuous cultivation system under no aeration and continuous aeration conditions daily for 9 days. Furthermore, to determine the optimal conditions for harvesting through centrifugation, different rotational speeds of the continuous centrifuge and different flow rates of the pump injecting G. smaydae + H. rotundata cells into the centrifuge were tested. Under continuous aeration, G. smaydaeproduction gradually decreased; however, without aeration, the production remained stable. Harvesting efficiency and the dry weights of omega-3 fatty acids of G. smaydae + H. rotundata cells at a rotational speed of 16,000 rpm were significantly higher than those at 2,000–8,000 rpm. However, these parameters did not significantly differ at injection pump flow rates of 1.0–4.0 L min-1. The results of the present study provide a basis for optimized production and harvest conditions for G. smaydae and other microalgae.

Serum measures of docosahexaenoic acid (DHA) synthesis underestimates whole body DHA synthesis in male and female mice

Females have higher docosahexaenoic acid (DHA) levels than males, proposed to be a result of higher DHA synthesis rates from α-linolenic acid (ALA). However, DHA synthesis rates are reported to be low, and have not been directly compared between sexes. Here, we apply a new compound specific isotope analysis model to determine n-3 PUFA synthesis rates in male and female mice and assess its potential translation to human populations. Male and female C57BL/6N mice were allocated to one of three 12-week dietary interventions with added ALA, eicosapentaenoic acid (EPA) or DHA. The diets included low carbon-13 (δ13C)-n-3 PUFA for four weeks, followed by high δ13C-n-3 PUFA for eight weeks (n=4 per diet, time point, sex). Following the diet switch, blood and tissues were collected at multiple time points, and fatty acid levels and δ13C were determined and fit to one-phase exponential decay modeling. Hepatic DHA synthesis rates were not different (P>.05) between sexes. However, n-3 docosapentaenoic acid (DPAn-3) synthesis from dietary EPA was 66% higher (P<.05) in males compared to females, suggesting higher synthesis downstream of DPAn-3 in females. Estimates of percent conversion of dietary ALA to serum DHA was 0.2%, in line with previous rodent and human estimates, but severely underestimates percent dietary ALA conversion to whole body DHA of 9.5%. Taken together, our data indicates that reports of low human DHA synthesis rates may be inaccurate, with synthesis being much higher than previously believed. Future animal studies and translation of this model to humans are needed for greater understanding of n-3 PUFA synthesis and metabolism, and whether the higher-than-expected ALA-derived DHA can offset dietary DHA recommendations set by health agencies.

Association of serum fatty acid pattern with depression in U.S. adults: analysis of NHANES 2011–2012

BackgroundExposure to different concentration levels of fatty acids (FAs) may have an impact on depression. However, previous studies using individual FAs may not reflect the performance of mixtures of various FAs, and the associations of FA patterns with depression remain unclear.MethodsWe conducted the cross-sectional analysis in 792 adults aged 18 and older with available serum FAs and depression screening data in the National Health and Nutrition Examination Survey (NHANES) 2011–2012. The serum concentrations of thirty FAs were measured using gas chromatography-mass spectrometry and their percentage compositions were subsequently calculated. Depression was defined as the Patient Health Questionnaire-9 score ≥ 10. We employed principal component analysis to derive serum FA patterns. We examined the association between these patterns and depression in the overall population and various subgroups through survey-weighted logistic regression.ResultsFour distinct patterns of serum FAs were identified: ‘high eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA); low docosatetraenoic acid (DTA) and docosapentaenoic acid (DPA) n-6’, ‘high long-chain saturated FA and long chain FA’, ‘low median-chain saturated FA and myristoleic acid’ and ‘low capric acid and lauric acid; high gamma-linolenic acid (GLA) and stearidonic acid (SDA)’ pattern. Individuals in the high tertile of ‘high EPA and DHA; low DTA and DPA n-6’ pattern score had 0.46 (95% CI: 0.22, 0.93) lower odds of developing depression compared to individuals in the lowest tertile after adjusting for confounders such as age, sex, physical activity and total energy intake, etc. The odds ratio (OR) of depression was increased in the population with the highest tertile of ‘low capric acid and lauric acid; high GLA and SDA’ pattern (OR: 2.45, 95% CI: 1.24, 4.83). In subgroup analyses, we observed that the association between ‘high EPA and DHA; low DTA and DPA n-6’ and depression persisted among specific demographic and lifestyle subgroups, including females, non-Mexican Americans, non-obese, those aged over 60 years, smokers and drinkers. Similarly, ‘low capric acid and lauric acid; high GLA and SDA’ showed stable associations in female, non-Mexican Americans and smokers.ConclusionsSerum FA patterns are associated with depression, and their relationships vary across sex, race, BMI, age, smoking and drinking subgroups, highlighting the importance of considering specific FA patterns within these demographic and lifestyle categories. Utilization of combined FA administration may serve as a mitigation measure against depression in these specific populations.

Docosahexaenoic acid, eicosapentaenoic acid, arachidonic acid, and neural tube defects in Tunisian population.

To determine the effect of maternal status in (plasma and red blood cell) folate, vitamin B12, homocysteine, and vitamin D, as well as their interaction with MTHFR (C677T and A1298C) and MTRR A66G polymorphisms, on maternal plasma docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and arachidonic acid (ARA) levels and the risk of neural tube defects (NTDs). ARA, EPA, and DHA composition was assessed using capillary gas chromatography. ARA and DHA levels were higher in controls than in case mothers for low plasma folate status. For low red blood cell folate status, DHA levels were higher in controls than in case mothers. For high homocysteine levels, ARA and DHA levels were higher in controls than in case mothers. NTD mothers had lower EPA and DHA levels for low vitamin B12 levels. NTD mothers had lower DHA levels for low vitamin D levels. For low plasma folate status, DHA levels in the MTHFR C677T gene and ARA and EPA levels in MTHFR A1298C gene were different among the three genotypes in case mothers. DHA levels in the MTHFR C677T gene were different among the three genotypes in case mothers for both low and high homocysteine levels. For low vitamin B12 levels, ARA and DHA levels were different among the three genotypes of the MTHFR C677T gene in case mothers. In the MTHFR C677T gene, ARA and DHA levels were different among the three genotypes in case mothers for low vitamin D levels. More advanced research is required to verify a suitable biochemical parameter status in relation to the genotypes in pregnant women.

Marine microalgae Schizochytrium demonstrates strong production of essential fatty acids in various cultivation conditions, advancing dietary self-sufficiency

IntroductionPolyunsaturated fatty acids (PUFAs) are essential nutrients that humans obtain from their diet, primarily through fish oil consumption. However, fish oil production is no longer sustainable. An alternative approach is to produce PUFAs through marine microalgae. Despite the potential of algae strains to accumulate high concentrations of PUFAs, including essential fatty acids (EFAs), many aspects of PUFA production by microalgae remain unexplored and their current production outputs are frequently suboptimal.MethodsIn this study, we optimized biomass and selected ω-3 PUFAs production in two strains of algae, Schizochytrium marinum AN-4 and Schizochytrium limacinum CO3H. We examined a broad range of cultivation conditions, including pH, temperature, stirring intensity, nutrient concentrations, and their combinations.ResultsWe found that both strains grew well at low pH levels (4.5), which could reduce bacterial contamination and facilitate the use of industrial waste products as substrate supplements. Intensive stirring was necessary for rapid biomass accumulation but caused cell disruption during lipid accumulation. Docosahexaenoic acid (DHA) yield was independent of cultivation temperature within a range of 28–34°C. We also achieved high cell densities (up to 9 g/L) and stable DHA production (average around 0.1 g/L/d) under diverse conditions and nutrient concentrations, with minimal nutrients required for stable production including standard sea salt, glucose or glycerol, and yeast extract.DiscussionOur findings demonstrate the potential of Schizochytrium strains to boost industrial-scale PUFA production and make it more economically viable. Additionally, these results may pave the way for smaller-scale production of essential fatty acids in a domestic setting. The development of a new minimal culturing medium with reduced ionic strength and antibacterial pH could further enhance the feasibility of this approach.

Nutritional quality of fish oil extracted from selected freshwater fish species

There is increased consumer awareness of the nutritional importance of fish oil consumption in recent time, however there is paucity of information on the quality of oil obtained from freshwater fishes available in this study area. Nutritional quality of fish oil extracted from 9kg each of Chrysichthys nigrodigitatus, Synodontis membranaceous and Clarias gariepinus were investigated with the aim of providing baseline information on the nutritional quality of oil in the fish available around the study area. Wet rendering, soxhlet extraction and microwave assisted extraction methods were used. Data collected were subjected to appropriate statistical analysis using SPSS 6.0. version. S. membranaceous have the largest oil yield while C. nigrodigitatus have the lowest oil yield; wet rendering oil extraction method gave the highest oil yield. The physical quality characteristics of S. membranaceous was the best with the lowest melting point (28.73 ±0.39°C), specific gravity (0.11± 0.01) and refractive index (1.14 ±0.01) while C. gariepinus oil had the poorest physical quality characteristics. Oil of C. nigrodigitatus have better chemical qualities than the rest having the lowest saponification value (9.81±0.01 mg KOH/g), iodine value (1.59±0.01 gl/100g), acid value (1.12±0.01 mgKOH/g) and free fatty acid (0.56±0.01%) while C. gariepinus oil was the poorest. C. nigrodigitatus also have the highest polyunsaturated fatty acid (PUFA) (18.75), highest Ʃn-3 FA (23.45), highest DHA (Docosahexaenoic acid) (4.93), highest eicosapentaenoic acid EPA+DHA (7.8). The oils chemical qualities are in the order of C. nigrodigitatus> S. membranaceous> C. gariepinus and are of good quality. Oil obtained from C. nigrodigitatus is therefore recommended due to its good chemical qualities using wet rendering oil extraction method. Information provided in this study will guide industrialists and nutritionists on the best extraction method and fish that will give highest oil yield and best oil quality in the study area.

Omega-3 fatty acids and health of auditory and vestibular systems: a comprehensive review.

The purpose of this study was to comprehensively review animal and human studies that explore the role of omega-3 PUFAs in maintaining the health of the auditory organ across all life stages. This narrative review involved searching Scopus, PubMed, Google Scholar, and Cochrane Library databases for relevant articles from December 1980 to July 2023. some animal and human studies suggest that both deficiency and excessive intake of long-chain omega-3 PUFAs, particularly docosahexaenoic acid (DHA), can lead to auditory neural conduction impairment and reduced hearing acuity from fetal development to old age (presbycusis). These effects are likely to be dependent on the dosage. Some research indicates that an excessive intake of omega-3, rather than a deficiency, can result in nutritional toxicity and hearing impairments. Animal studies highlight the positive impact of omega-3 supplements with high DHA content in addressing hearing damage, but human research on this subject is limited. Furthermore, certain studies propose that omega-3 PUFAs may prevent or delay age-related hearing loss, with high plasma omega-3 concentration, particularly long-chain omega-3 PUFA, linked to reduced hearing loss. Additionally, consuming fish more than twice a week may be associated with a lower risk of hearing loss in adulthood, with these effects potentially influenced by age and gender. However, the majority of studies have been conducted on animals, and clinical trials are scarce. Research on the influence of omega-3 PUFAs on the peripheral and central vestibular systems remains limited. This article delves into the impact of omega-3 on the auditory-vestibular system, exploring its influence on neurodevelopment, protection, and treatment. It not only highlights specific research gaps but also offers valuable insights for potential future studies.

Unsaturated fatty acids, omega-3 index and hospitalization in MISC

The growing interest in Omega-3 fatty acids as diagnostic markers or new therapeutic approaches also for COVID-19 disease, led us to investigate the presence of potential correlations between Omega-3 fatty acids’ levels in whole blood and days of hospitalization or admission to the paediatric intensive care unit (PICU) in 51 children with MIS-C diagnosis following SARS-CoV-2 infection. A statistically significant negative correlation was observed between days of hospitalization and docosapentaenoic acid (22:5n-3,DPA), docosahexaenoic acid (DHA) and total Omega-3 FA levels. Dividing the study group into quartiles according to Omega-3-Index (O3I), no statistically significant difference was observed with respect to the PICU admission rate. In contrast, the number of days of hospitalization in Q4 (O3I ≥ 2.51 %) was different from the number observed in groups Q1-3 (O3I < 2.51 %), with subjects showing higher O3I needing shorter hospitalizations than the subjects with lower O3I. According to previous study investigating O3I in adults affected by Sars-cov-2 we explored the levels of this nutrients in children with MIS-C. Our exploratory study shows that high DPA, DHA and O3I levels could be effective in reducing the length of hospitalization.

Effect of high-fat diet on the fatty acid profiles of brain in offspring mice exposed to maternal gestational diabetes mellitus.

Fatty acids play a critical role in the proper functioning of the brain. This study investigated the effects of a high-fat (HF) diet on brain fatty acid profiles of offspring exposed to maternal gestational diabetes mellitus (GDM). Insulin receptor antagonist (S961) and HF diet were used to establish the GDM animal model. Brain fatty acid profiles of the offspring mice were measured by gas chromatography at weaning and adulthood. Protein expressions of the fatty acid transport pathway Wnt3/β-catenin and the target protein major facilitator superfamily domain-containing 2a (MFSD2a) were measured in the offspring brain by Western blot. Maternal GDM increased the body weight of male offspring (P < 0.05). In weaning offspring, factorial analysis showed that maternal GDM increased the monounsaturated fatty acid (MUFA) percentage of the weaning offspring's brain (P < 0.05). Maternal GDM decreased offspring brain arachidonic acid (AA), but HF diet increased brain linoleic acid (LA) (P < 0.05). Maternal GDM and HF diet reduced offspring brain docosahexaenoic acid (DHA), and the male offspring had higher DHA than the female offspring (P < 0.05). In adult offspring, factorial analysis showed that HF diet increased brain MUFA in offspring, and male offspring had higher brain MUFA than female offspring (P < 0.05). The HF diet increased brain LA in the offspring. Male offspring had higher level of AA than female offspring (P < 0.05). HF diet reduced DHA in the brains of female offspring. The brain protein expression of β-catenin and MFSD2a in both weaning and adult female offspring was lower in the HF + GDM group than in the CON group (P < 0.05). Maternal GDM increased the susceptibility of male offspring to HF diet-induced obesity. HF diet-induced adverse brain fatty acid profiles in both male and female offspring exposed to GDM.

Thiamine Deficiency M74 Developed in Salmon (Salmo salar) Stocks in Two Baltic Sea Areas after the Hatching of Large Year-Classes of Two Clupeid Species—Detected by Fatty Acid Signature Analysis

Lipid-related thiamine (vitamin B1) deficiency of Baltic salmon (Salmo salar), the M74 syndrome, is generally caused by feeding on abundant young sprat (Sprattus sprattus) in the Baltic Proper, the main foraging area of these salmon. In 2014, a strong year-class of sprat was hatched in the Baltic Proper, and a strong herring (Clupea harengus) year-class was hatched in the Gulf of Bothnia, where herring is the dominant salmon prey. The fatty acid (FA) signatures of prey fish in muscle or eggs of second sea-year spawners suggested that 27% of wild River Simojoki and 68% of reared River Dal salmon remained in the Gulf of Bothnia in 2014 instead of continuing to the Baltic Proper. In 2016, 23% of the M74 females of the River Simojoki and 58% of the River Dal originated from the Gulf of Bothnia, and 13% and 16%, respectively, originated from the Baltic Proper. Some salmon from the River Neris in the southern Baltic Proper had also been feeding in the Gulf of Bothnia. In general, low free thiamine (THIAM) concentration in eggs was associated with high lipid content and high docosahexaenoic acid (DHA, 22:6n−3) and n−3 polyunsaturated FA (n−3 PUFA) concentrations in muscle but not in eggs. A higher THIAM concentration and lower proportions of DHA and n−3 PUFAs in Arctic Ocean salmon eggs, despite higher egg lipid content, indicated that their diet contained fewer fatty fish than the Baltic salmon diet. Hence, M74 originated by foraging heavily on young fatty sprat in the Baltic Proper or herring in the Gulf of Bothnia.

Effect of high DHA and ARA fortification on lipid oxidation of infant formula powder

ABSTRACT Our objective was to assess the impact of fortified high-dose docosahexaenoic acid (DHA) and arachidonic acid (ARA) in infant formula powders (IFs) on stability. We compared and evaluated the stability of IFs containing high and low doses of DHA and ARA over a 6-month storage period at 37°C. While most formulations showed minimal changes in unsaturated fatty acid content of during storage, significant losses of DHA and ARA were observed in some high-dose formulations. Furthermore, this study noted consistent trends in the changes of vitamin C and vitamin E across both formula groups. Notably, the high-dose group formulas exhibited a higher presence of volatile organic compounds (VOCs) during storage, along with a more pronounced increase in thiobarbituric acid-reactive substance values (TBARS). In conclusion, the inclusion of high doses of DHA and ARA in IFs may compromise their oxidative stability.

Effect of high DHA and ARA fortification on non-enzymatic browning of infant formula powder

ABSTRACT To investigate the effect of adding high-dose docosahexaenoic acid (DHA) and arachidonic acid (ARA) on the stability of infant formula powders (IFs), IFs fortified with high-dose and low-dose DHA and ARA were compared and evaluated during storage at 37°C for six months. We specifically focused on the changes to IFs caking, amino acid content, and 5-hydroxymethylfurfural (HMF) content. We found that during the storage process, there was no significant change in the amino acids of IFs following supplementation with high- or low-doses of DHA and ARA. However, HMF and color difference (∆E) increased with the length of storage time. A comparison between the high-dose and low-dose groups revealed that the addition of high-dose DHA and ARA did not cause an additional increase in the HMF but exacerbated the caking of IFs. The addition of high-dose DHA and ARA did not exacerbate the non-enzymatic browning of IFs.

Integration of genetic engineering and multi-factor fermentation optimization for co-production of carotenoid and DHA in Schizochytrium sp

Schizochytrium sp., a microalga with high lipid content, holds the potential for co-producing docosahexaenoic acid (DHA) and carotenoids. In this study, the ability of Schizochytrium sp. to naturally produce carotenoids was systematically explored. Further, by enhancing the precursor supply of geranylgeranyl diphosphate, regulating carbon source through sugar limitation fermentation and employing a combination of response surface methodology and artificial neural networks to precisely optimize nitrogen sources, a new record of 43-fold increase in β-carotene titer was achieved in the 5L bioreactor (653.2 mg/L). Meanwhile, a high DHA content was maintained (13.4 g/L). Furthermore, the use of corn stover hydrolysate has effectively lowered the production costs of carotenoid and DHA while sustaining elevated production levels (with total carotenoid titer and DHA titer reached 502.0 mg/L and 13.2 g/L, respectively). This study offers an efficient and cost-effective method for the co-production of carotenoid and DHA in Schizochytrium sp..

Comparative analysis of nutrients in muscle and ovary between an improved fish and its parents

In previous studies, an allodiploid lineage (WR-F1-F5) was established by the distant hybridization of white crucian carp (Carassius cuvieri, WCC, ♀) and red crucian carp (Carassius auratus red var., RCC, ♂), an allodiploid fish (WR-II) was produced by WR-F1 (♀) × WCC (♂). In this study, the nutrients in the muscle and ovary of WR-II and its parents (WCC, RCC, and WR) were investigated, including protein, fat, amino acid, docosahexaenoic acid (DHA), moisture, and ash. The results showed that the protein content of WR-II in muscle and ovary (17.90 % and 25.60 % respectively) was higher than that of WR, and was significantly higher than that of WCC and RCC (p < 0.05). The fat content of WR-II in muscle and ovary (4.30 % and 5.31 % respectively) was higher than that of WR and was significantly higher than that of WCC and RCC (p < 0.05), and the muscle and ovary of WR-II showed rich DHA content (0.32 % and 0.54 % respectively) than that of WCC and RCC (p < 0.05). Fifteen amino acids were detected in WR-II and its parents, the total amino acid (TAA) content of WR-II in muscle and ovary (15.49 % and 18.43 % respectively) was significantly higher than that of WCC (p < 0.05), the delicious amino acid (DAA) content of WR-II in muscle and ovary (6.56 % and 8.29 % respectively) was different degrees higher than that of WCC, RCC, and WR. The moisture and carbohydrates of WR-II in muscle and ovary were lower than those in WCC and RCC. Furthermore, protein, fat, TAA, and DAA content in the ovary were significantly higher than those in muscle (p < 0.05), showing tissue differences in all detected fish. This study indicated that WR-II had the characteristics of high protein, high fat, high DHA, high TAA, high DAA, low moisture, and low carbohydrates, which provided theoretical support for its application.

Metabolic engineering of Schizochytrium sp. for superior docosahexaenoic acid production

Schizochytrium sp. is an industrial producer of docosahexaenoic acid (DHA), which is an important omega-3 polyunsaturated fatty acid used in the nutraceutical and food industry. Here, we rewired the carbon metabolism of Schizochytrium sp. ATCC20888 for superior DHA production and constructed 18 engineered strains through combinatorial gene manipulation of 8 crucial genes (acc, acl, ampD, dga1, mae, mfe1, pex10, and zwf) related to lipogenesis. Reducing β-oxidations (∆pex10, ∆mfe1), reinforcing the biosynthetic precursors supply (OACC, OACL, OAMPD), reinforcing NADPH supply (OMAE, OZWF), or promoting TAG formation (ODGA1) efficiently promoted DHA and lipid production of Schizochytrium. MAE and DGA1 overexpression exhibited cooperativity towards increasing DHA production and lipogenesis in the WT strain and ACC-overexpression strain, but had no cooperative advantage in the ∆pex10 strain. The highest lipid content (82.2%) and DHA yield (7.04 g/L) were obtained in an engineered strain OACL-ACC/∆pex10, which is 72.1% higher than DHA yield of parental strain. Therefore, inhibition of β-oxidations and ample biosynthetic precursors supply are the determining factors for high DHA productivity and lipid accumulation of Schizochytrium.

The Eicosapentaenoic Acid and Docosahexaenoic Acid Content Reported in the Nutrition Panel of Fish Oil Supplements and Formula Milks Promoted for Young Children in Selected Markets

The aim of this study was to investigate the eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) content found in fish oil supplements and formula milks for young children sold in Europe, the Middle East, and North Africa's local markets and online stores. To allow comparison of fish oil supplements and formula milks, information about the EPA and DHA content was collected from the nutrition panel of each product. A total of 79 fish oil supplements and 70 formula milks were studied. Out of the 32 fish oil supplements in local markets 12 products (37.5%) and of the 47 fish oil supplements in Amazon online stores 12 products (25.5%) contained more EPA than DHA. The highest DHA:EPA ratio for fish oil supplements was 4.6. The percentage of Recommended Dietary Intake for DHA, based on 250 mg daily, ranged from 3.2% to 558% for the fish oil supplements, and the range of 0.4% to 25.2% was found for the formula milks. Fish oil supplements provided high daily dose of DHA, which was significantly higher than that provided by the formula milks.