Fatty Acid Methyl Ester Profiles Research Articles

Pasture-finishing of cattle in Western U.S. rangelands improves markers of animal metabolic health and nutritional compounds in beef

As environmental and health concerns of beef production and consumption mount, there is growing interest in agroecological production methods, including finishing beef cattle on pastures with phytochemically diverse grasses, forbs, and/or shrubs. The goal of this metabolomics, lipidomics, and fatty acid methyl ester profiling study was to compare meat (pectoralis profundus) of Black Angus cattle from two commercial US beef finishing systems (pasture-finished on Western U.S. rangeland; n = 18 and grain-finished in a Midwest U.S. feedlot; n = 18). A total of 907 out of 1575 compounds differed in abundance between pasture-finished and grain-finished beef samples (all, false discovery rate adjusted P < 0.05). Pasture-finished beef contained higher levels of phenolic antioxidants (2.6-fold), alpha-tocopherol (3.1-fold), nicotinate/vitamin B3 (9.4-fold), choline (1.2-fold), myo-inositol (1.8-fold), and omega-3 fatty acids (4.1-fold). Grain-finished beef contained higher levels of gamma-tocopherol (14.6-fold), nicotinamide/vitamin B3 (1.5-fold), pantothenate/vitamin B5 (1.3-fold), and pyridoxine/vitamin B6 (1.3-fold); indicating that feeding some grain (by-products) could be beneficial to increase levels of certain B-vitamins. Pasture-finished beef samples also displayed lower levels of oxidative stress (homocysteine, 0.6-fold; and 4-hydroxy-nonenal-glutathione, 0.4-fold) and improved mitochondrial function (1.3-fold) compared to grain-finished animals. Two potential metabolites of fluoroquinolone antibiotics, 2,8-quinolinediol and 2,8-quinolinediol sulfate, were only observed in grain-finished beef, though the source remains unknown. While pasture-finished cattle displayed improved markers of metabolic health and concentrated additional, potentially health-promoting compounds in their meat, our findings should not be interpreted as that grain-finished beef is unhealthy to consume. Randomized controlled trials in humans are required to further assess whether observed differences between pasture-finished and feedlot-finished beef have an appreciable effect on human health.

Salicornia seed oil: A high-yielding and sustainable halophytic feedstock for biodiesel and energy in underutilized hypersaline coastal deserts

Addressing the critical need for sustainable biofuel sources that do not compete with prime agricultural land, this work presents a promising evaluation of Salicornia species as novel biodiesel feedstocks cultivable in underutilized coastal hypersaline regions. The research leveraged a successful pilot plant application, demonstrating the practical large-scale cultivation of Salicornia as an energy feedstock in these environments. Through innovative integration of advanced analytical techniques and multivariate statistical approaches, S. bigelovii and S. sinus-persica were comprehensively analyzed for their biodiesel potential. S. bigelovii seeds exhibited superior oil content (20.6 wt%) compared to S. sinus-persica (11.6 wt%), with an exceptional oil yield potential of 11,442 kg/ha, surpassing established biodiesel feedstocks. Oil extraction experiments also showed that cleaned high-density S. bigelovii seeds yielded up to 36.0 % oil content. Fatty acid methyl ester (FAME) profiling and biodiesel properties confirmed that both species meet ASTM D6751 and EN 14214 standards. The multivariate analyses revealed interesting relationships between Salicornia oils and other feedstocks, providing valuable insights for future breeding programs. Furthermore, advanced imaging elucidated Salicornia seed microstructures and oil distribution. This research establishes a robust analytical framework for evaluating novel biodiesel sources with significant implications for sustainable energy production in marginal lands. The findings pave the way for developing high-yielding, salt-tolerant energy crops, enhancing biodiesel feedstock cultivation in salt-affected coastal areas worldwide. By tackling both energy security and land use challenges in a changing climate, the study marks a breakthrough in sustainable biodiesel research.

Comprehensive comparison of fatty acid methyl ester profile in different food matrices using microwave-assisted extraction and derivatization methods and comprehensive two-dimensional gas chromatography coupled with flame ionization detection

Analyzing fatty acids provides key insights into fat composition for industrial applications and their implications for nutrition and health. Typically, fatty acid analysis involves extracting lipids from the matrix and converting them into fatty acid methyl esters (FAME) through a derivatization process before gas chromatography (GC) analysis. Either one-step or two-step procedures can be found in the literature and as official methods. In this work, different methods exploiting microwave-assisted processes were compared with two official methods from the American Oil Chemical Society (AOCS). Especially, two types of microwave-assisted extractions were employed: solvent extraction and extraction with hydrolysis. The extracts were derivatized using either BF3 or a microwave-assisted methanolic hydrogen chloride solution. These combinations of extraction and derivatization methods were compared also with one-step microwave-assisted extraction and derivatization, and two AOCS reference methods, resulting in seven different methods applied to six different food matrices. The performance of the different procedures was compared based on the FAME profile obtained from the comprehensive two-dimensional GC (GC × GC)-FID analysis.Microwave-assisted processes were shown to be effective, yielding results comparable to the official methods in both the one-step and two-step methods. Moreover, it was shown that the BF3 derivatization could be safely replaced with microwave-assisted derivatization with methanolic hydrogen chloride, providing equivalent performances while enhancing operator safety and environmental friendliness. Some discrepancies in the FAMEs profile were highlighted for the sample of oats, the only explicitly requiring acidic hydrolysis for lipid extraction. Further studies are required to understand the reasons behind these differences and develop a suitable modified method. In conclusion, all the methods were evaluated for greenness and blueness with two specific tools: AGREEprep and BAGI.

The analysis of lamb and beef fatty acids with a 30 m BPX70 column is comparable with a 120 m column

Gas chromatography (GC) analysis of fatty acid methyl esters (FAME) typically uses long capillary columns (≥ 100 m) which can be expensive and time consuming. The current study determined whether the major FAME of interest for human health in lamb and beef can be quantified using a 30 m compared with 120 m moderately polar capillary (BPX70) column. Lamb and beef samples with a range of intramuscular fat content from either grass- or grain-fed animals were analysed. All major FAME of human health importance, including omega-3 and omega-6 polyunsaturated fatty acids and conjugated linoleic acid (CLA) isomers, could be identified on the 30 m BPX70 column. The correlation (r2) for fatty acid percentage between columns was > 0.98 for all major n–3PUFA and > 0.86 for all major CLAs. When animals were fed a grain-based diet, C18:1n–7t (vaccenic acid) could not be resolved from C18:1n-8t when analysed on the 30 m column. The FAME profile of lamb and beef, particularly those important for nutritional composition tables, can be determined using a 30 m BPX70 column, thereby saving time and expense compared with longer columns. Particular care should be employed when analysing samples from grain-fed animals due to co-eluting of C18:1n–8t.

Fatty Acid Methyl Ester Profiling of Californian Xylella fastidiosa Strains

Xylella fastidiosa ssp. fastidiosa ( Xff) is the causal agent of Pierce's disease of grapevine, a management-intensive and potentially deadly disease. However, different stains and other subspecies, such as Xylella fastidiosa ssp. multiplex ( Xfm), exist in the same regions and vary in capacity to cause disease. All strains differ in the fatty acids that comprise cell membranes, as these allow adaptations to specific host microenvironments. Therefore, studies were initiated to observe the fatty acid profiles of different Californian Xf isolates via fatty acid methyl ester (FAME) analysis. Observations revealed that the four Xff strains had similar FAME profiles that were distinct from those of the three Xfm strains, even in isolates that originated from the same host plant species. These data show consistent differences between Xff and Xfm strains and demonstrate the potential that FAME profiling has for Xylella subspecies identification of novel isolates. [Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 “No Rights Reserved” license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law, 2024.

Bioprospection of the Antarctic Diatoms Craspedostauros ineffabilis IMA082A and Craspedostauros zucchelli IMA088A.

In extreme environments such as Antarctica, a diverse range of organisms, including diatoms, serve as essential reservoirs of distinctive bioactive compounds with significant implications in pharmaceutical, cosmeceutical, nutraceutical, and biotechnological fields. This is the case of the new species Craspedostauros ineffabilis IMA082A and Craspedostauros zucchellii IMA088A Trentin, Moschin, Lopes, Custódio and Moro (Bacillariophyta) that are here explored for the first time for possible biotechnological applications. For this purpose, a bioprospection approach was applied by preparing organic extracts (acetone and methanol) from freeze-dried biomass followed by the evaluation of their in vitro antioxidant properties and inhibitory activities on enzymes related with Alzheimer's disease (acetylcholinesterase: AChE, butyrylcholinesterase: BChE), Type 2 diabetes mellitus (T2DM, α-glucosidase, α-amylase), obesity (lipase) and hyperpigmentation (tyrosinase). Extracts were then profiled by ultra-high-performance liquid chromatography-mass spectrometry (UPLC-HR-MS/MS), while the fatty acid methyl ester (FAME) profiles were established by gas chromatography-mass spectrometry (GC-MS). Our results highlighted strong copper chelating activity of the acetone extract from C. ineffabilis and moderate to high inhibitory activities on AChE, BChE, α-amylase and lipase for extracts from both species. The results of the chemical analysis indicated polyunsaturated fatty acids (PUFA) and their derivatives as the possible compounds responsible for the observed activities. The FAME profile showed saturated fatty acids (SFA) as the main group and methyl palmitoleate (C16:1) as the predominant FAME in both species. Overall, our results suggest both Antarctic strains as potential sources of interesting molecules with industrial applications. Further studies aiming to investigate unidentified metabolites and to maximize growth yield and natural compound production are required.

Potential of algal oil production from secondary treated sewage: a study using Chlorella vulgaris and synthetic wastewater

ABSTRACTTo assess the potential of using the secondary treated wastewater for the production of algal biofuel, batch experiments were carried out in photobioreactors using indigenous Chlorella vulgaris isolated from the natural freshwater body. Secondary treated wastewater with partial nitrification was simulated using various proportions of NO3-N and NH4-N while keeping the total nitrogen the same. Experiments with similar concentrations of nitrate without the NH4-N were used for comparison. In the presence of only NO3-N in the concentration range of 9–37 mg/L, the growth and fatty acid methyl ester (FAME) production was similar to the literature reports. When NH4-N was present along with NO3-N, the biomass growth was adversely affected, indicating an impact on the metabolic activity. For the same initial concentrations of nitrate in the culture, the maximum biomass concentration was reduced by 50–60% in the presence of NH4-N. The FAME profile changed significantly and a new FAME was identified, suggesting an impact on the lipid synthesis pathway. Comparison and analysis with the help of existing literature indicated that the adverse effect due to NH4-N was a function of pH. The growth, biomass yield, and FAME production were unaffected by a wide range of phosphorus concentrations. Maximum fatty acid methyl ester (FAME) suitable for biodiesel production (fatty acid carbon chain length C16 to C18) was 381.01 mg/L (224.58 mg/g of dry biomass), produced at NO3-N concentration of 18.5 mg/L and initial nitrogen loading per unit biomass of 0.37 g NO3-N/g of dry biomass.

Unveiling the anticancer potentiality of single cell oils produced by marine oleaginous Paradendryphiella sp. under optimized economic growth conditions

Bioprospecting about new marine oleaginous fungi that produce advantageous bioproducts in a green sustainable process is the key of blue bioeconomy. Herein, the marine Paradendryphiella sp. was utilized for single cell oils (SCOs) production economically, via central composite design, the lipid content enhanced 2.2-fold by 5.5 g/L lipid yeild on seawater-based media supplemented with molasses concentration 50 g/L, yeast extract, 2.25 g/L at initial pH value (5.3) and 8 days of static incubation. Subsequently, the fatty acid methyl esters profiles of SCOs produced on optimized media under different abiotic conditions were determined; signifying qualitative and quantitative variations. Interestingly, the psychrophilic-prolonged incubation increased the unsaturation level of fatty acids to 59.34%, while ω-6 and ω-3 contents representing 23.53% and 0.67% respectively. Remarkably, it exhibited the highest EC100 dose by 677.03 µg/mL on normal human lung fibroblast Wi-38 cells. Meanwhile, it showed the highest inhibiting proliferation potential on cancer cell lines of A549, MDA-MB 231 and HepG-2 cells by 372.37, 417.48 and 365.00 µg/mL, respectively. Besides, it elevated the oxidative stress, the expression of key apoptotic genes and suppressed the expression of key oncogenes (NF-κB, BCL2 and cyclin D); implying its promising efficacy in cancer treatment as adjuvant drug. This study denoted the lipogenesis capacity of Paradendryphiella sp. under acidic/alkaline and psychrophilic/mesophilic conditions. Hereby attaining efficient and economic process under seasonal variation with different Egyptian marine sources to fill the gap of freshwater crisis and simultaneously preserve energy.

Biological treatment of agro-processing industrial effluents from tannery, coffee and dairy plants using green algae (&lt;i&gt;Chlorella Ssp&lt;/i&gt;.) cultured in a photo bioreactor

Due to increased environmental pollution as a result of high emission rates from agro-processing industries, the effluents must be cleaned up before being released into the environment. This study outlines the use of green algae for nutrient removal from agro-processing effluents discharged from three agro-industries (namely coffee, dairy, and tannery) in Kenya and how they can be used for the propagation of microalgae for biofuel production. Green algae were grown inside a photobioreactor containing the three agro-industrial effluents as nutrient media for 21 days. Thereafter, the algae were harvested and evaluated for biofuel production. The effectiveness of green algae (chlorella ssp) to extract the cations from the various agro-processing effluents was used to gauge how well they performed. Additionally, the algae growth rate, quantity of lipids, and biomass generated were used to evaluate the strains' effectiveness in producing biofuel. The results indicate that the highest maximum algae growth rate of 14.528 mg/mL occurred in the dairy effluent. The corresponding values for the coffee and tannery effluents were 13.016 mg/mL and 10.866 mg/mL, respectively. Biochemical analysis was done to establish the amount of biomass in the algae. The results showed that there was higher biomass productivity per day of 293.944, 124.849, and 91.997 μg/mL for the dairy, coffee, and tannery effluents, respectively. The contents of linolenic acid in the chlorella strain in the dairy, coffee, and tannery effluents were 13.21, 12.86, and 15.98%, respectively. The values obtained were slightly above the recommended lower limit value of 12% (EN 14214, 2004) for the production of quality biofuels. The results further show that high chemical oxygen demand removal (maximum of 47.7–67.8%) and total phosphorus removal (maximum of 95%) were achieved in all three effluents. Finally, the fatty acid methyl ester profiles produced indicated that the lipid content of the cultivated green algae was appropriate for the production of biofuel.

No‐till marginally mitigates the impact of harvesting corn stover on soil microbial parameters

AbstractHarvesting corn stover can negatively impact soil chemical and physical properties, but less is known regarding its effects on soil microbiology. We evaluated the impact of corn (Zea mays L.) stover removal level (SRL) on soil microbial biomass (MB) and extracellular enzyme activities (EEAs) in irrigated, continuous corn located in eastern Nebraska. Soil fatty acid‐methyl esters (FAMEs) and EEA of eight soil enzymes were measured over 2 years, 0‐ to 20‐cm soil depth, under conventional disk tillage (CT) and no‐till (NT) under three SRLs. Soil chemical properties were measured as explanatory variables for changes in soil microbial communities and their enzymatic potential. Potential EEA of all enzymes decreased with stover removal and tillage. Soil bacterial biomass (BB) and fungal biomass (FB) decreased with SRL, while mycorrhizal biomass was unresponsive. Impacts of tillage on MB groups varied by year; however, FB was consistently higher under CT. At all growth stages, NT with all stover retained, a “soil conservation target” had distinct soil enzyme and bacterial FAME profiles compared to CT across all SRLs and to NT under high and sometimes moderate SRLs. Principal component analysis of soil properties was dominated by SRL with EEAs, BB, soil organic matter (SOM), water‐extractable carbon, and H3A‐extractable potassium being positively correlated to stover retention. Reduced input of microbial substrates also led to a loss of fine particulate organic matter, an indicator correlated to stable macroaggregation. Because NT partially ameliorated the negative impact of stover removal on BB, SOM fractions, and soil enzymes critical to nutrient cycling, pairing NT with stover removal may be more sustainable in the long term.

Investigation on the Microbiological Quality and Fatty Acid Methyl Esters Composition of Commercially Available Cold-pressed Nigella sativa L. Oil

Background:: Nigella sativa is a traditional plant with several ethno-medicinal activities. There have been several health advantages associated with Nigella sativa (Ns) L. oil, which has a high concentration of bioactive compounds. Method:: This research aimed to examine the fatty acid methyl ester profiles, microbiological profiles, and aflatoxin profiles of cold-pressed Ns oils acquired from Turkish herbalists. For this, the fatty acids methyl esters (FAMEs) content and microbiological purity of 10 different Ns oils were examined. Results:: The principal FAME components in Ns seed oils were linoleic (C18:2), oleic (C18:1), and palmitic acid (C16:0), with relative percentages of 34.17-57.54%, 19.41-30.52%, and 7.05-12.54%, respectively. The quantity of total saturated fatty acids (SFA) in all investigated oils ranged from 11.47 to 18.69%, while the amount of total unsaturated fatty acids ranged from 80.94 to 88.53%. Six of ten products (0.35-1.49%) were found to contain cis-11 eicosenoic acid, a chemical unique to Ns oil. Conclusion:: Although no Aflatoxin was found in any of the samples, Enterobacteriaceae levels were exceptionally low, and yeast mold concentrations surpassed the Turkish Food Codex's permissible limit values.

Nutritional Value of Meals Designed for a School-Based Food Aid Program and Comparison with Similar Commercial Products: An Example of Good Practice from the DIATROFI Program.

Providing meals of high nutritional value should be the principal objective of large-scale school-based food aid programs. This study aimed at highlighting the nutritional value of meals distributed in the school-based food assistance DIATROFI Program by comparing them to their commercially available counterparts. For the purpose of this study, n = 13 DIATROFI meals and n = 50 commercial products from the 2016-2017 school year, and n = 12 DIATROFI meals and n = 40 commercial products from the 2022-2023 school year were selected. The protein, carbohydrate, total sugar, dietary fiber, total fat, sodium/salt content, and fatty acid methyl ester profile of DIATROFI meals were estimated through recipe simulation and national/international food databases, and verified through laboratory analyses while the relevant information was extracted from the label for commercial products. As verified by laboratory analyses and in comparison with food labels, most DIATROFI meals had lower total fat, saturated fatty acid, and sugar content, and most had higher dietary fiber content during both years. Many recipes' nutrient profiles also improved over time. DIATROFI meals present significant advantages over available commercial products. Such tailored-made school meals can prove to be advantageous in terms of nutrition profile compared to commercially available, which have yet to be impacted by food reformulation.

Establishment of Stable Genetic Transformation Conditions for Novel Thermotolerant Scenedesmus sp. (Chlorophyta)

Microalgae became an attractive source of high value compounds such as fatty acids, carotenoids and other nutrients in recent years. In a previous study, the characterization of a novel thermo-tolerant freshwater microalga, Scenedesmus sp. ME02 with high phenolic content, particularly rich in flavonoids was done. Here, two different approaches are reported to increase the efficiency of the growth parameters of this strain. Firstly, the effects of phosphorus (P) depletion on biomass and lipid characteristics of Scenedesmus sp. ME02 were investigated. Although, P depletion resulted in a slight reduction in biomass productivity of microalgae and had a minimal effect on the lipid content and productivity; fatty acid methyl ester profile changed substantially. Particularly, percent oleic acid (18:1) increased by more than two-fold, whereas percent linolelaidic acid (C18:2n6t) and linolenic acid (C18:3n6) decreased significantly when cells were switched from P-replete (control) to P-deplete conditions. Overall, the polyunsaturated fatty acid content was significantly reduced. Secondly, stable genetic transformation conditions for Scenedesmus sp. ME02 via electroporation were optimized using two different transformation vectors. GFP gene expression was detected in colonies transformed with both vectors by RT-PCR. GFP protein expression was detected in the transgenic lines one year after initial transformation by confocal microscopy.

Kinetic and thermodynamic evaluations of oil extraction from immobilized Chlorella vulgaris using different solvents

Investigating the effect of different solvents used for microalgae oil extraction on the determinations of kinetic values and thermodynamic parameters is a compelling novel approach for the current study. The primary concern of microalgae oil extraction is selecting a solvent system because it has a massive influence on the extraction yield, composition, and oil quality. Three different solvent systems were inspected to determine the suitable solvent for the oil extraction from immobilized Chlorella vulgaris: heptane, heptane:methanol, and heptane:ethanol. The research methodology begins with the immobilization of microalgae cells. The matured immobilized beads were then harvested, and dried biomass was recovered. The oil was extracted by solvent extraction method using the solvents mentioned. Finally, the extracted oil was trans-esterified and analyzed for fatty acid methyl ester profile. Based on the results calculated, heptane is determined to extract the most oil with 27.42 %, followed by H:M and H:E at the highest temperature and longest running time. When the polar solvent is mixed with a non-polar solvent, the mixture has the least kinetic value and immense activation energy. However, the activation energy for heptane is only 89.06 kJ/mol. Another essential objective of this research is to determine the effects of solvents on the thermodynamics parameters. The extraction process of microalgae oil using heptane alone is determined to have a ΔH value of 0.111 kJ/mol, followed by 0.201 and 0.102 kJ/mol for solvent system H:M and H:E respectively. All the values obtained are positive, thus making the extraction processes using various solvents to be endothermic. The positive values of ΔS and the negative values of ΔG indicated that the oil extraction using heptane is thermodynamically spontaneous and irreversible, thus making it economically feasible. The fatty acids methyl esters such as palmitic, stearic, oleic, linoleic, and linolenic were the prime constituents quantified in the oil extracted using heptane compared to other solvent systems. Therefore, with the larger and increasing kinetic values and lowest activation energy, it can be concluded that heptane is the most suitable solvent for the oil extraction of immobilized Chlorella vulgaris compared to other solvent systems employed in the current research work.

Persica Akhani Salicornia as novel biodiesel feedstock production for economic prosperity in salty and water scarcity areas: Optimized oil extraction process and transesterification reaction using new magnetic heterogenous nanocatalysts

As a new biodiesel feedstock, the oil extraction procedure from the seeds of the plant Salicornia (Persica Akhani subspecies) has been developed. Oil extraction from the seeds of the Salicornia Persica Akhani has been researched utilizing two different organic solvents and four different procedures, including the Soxhlet method, the traditional approach, the shaker method, and the ultrasonic probe method. The results indicated that oil yield by ultrasonic probe technique was higher than the other methods in a short time. Based on the outcomes, extracting the oil from Salicornia seeds using hexane resulted in a greater yield of oil than petroleum ether. This was true across all methods of extraction. The Physico-chemical properties and antioxidant activity of extracted oil suggested its suitability for biodiesel production. To transesterification reaction of Salicornia seeds oil with methanol into biodiesel, the heterogeneous magnetic Zn0.4Ni0.6Fe2O4 and Zn0.4Ni0.6Fe2O4@SO3H nanocomposites have been synthesized by sol-gel auto combustion procedure. FT-IR, FE-SEM, EDS, and VSM were used to determine the characteristics of the heterogeneous nanocomposites. These nanoparticles have a strong attraction to an outside magnet, which makes it much easier to collect them from the reaction environment for subsequent reuse. In the process of transesterification of Salicornia oil with methanol, novel sulfonated heterogeneous magnetic catalysts with a high density of superacid sites on the surface (2.50 mmol SO3H g−1) and significant magnetization (60 emu/g) afforded high activity and produced a biodiesel yield of 96%. In addition, the magnetic Zn0.4Ni0.6Fe2O4@SO3H nanoparticles could be reused up to five times in the process of turning oil into biodiesel, which resulted in reduced expenses associated with the manufacture of biodiesel. FT-IR and SEM analyses were performed both before and after the transesterification process, and the results showed that the absorption bands and particle distribution were practically the same in both new and used catalysts. The analysis of the FT-IR spectra reveals indications of the transformation of Salicornia oil into fatty acid methyl esters (FAMEs). Gas chromatography (GC) study of the FAME profiles of the as-prepared biodiesel also indicated that palmitic acid (C16:0) was the most saturated fatty acid (8.44%–8.50%), while linoleic acid (18:2) was the predominant unsaturated fatty acid (60.94%–60.97%).

Lipid content and fatty acid methyl ester profile by Chromochloris zofingiensis under chemical and metabolic stress

AbstractThis work encompasses the effect of chemical and metabolic stress on lipid content and fatty acid methyl ester (FAME) profile by Chromochloris zofingiensis. To this aim, a control medium amended with specific concentrations of sodium chloride (15 g L−1, 30 g L−1, and 60 g L−1) and of ethanolamine (ETA) and triethylamine (TEA) (0.050 g L−1, 0.100 g L−1, and 0.150 g L−1) has been used for the cultivation of this strain. A better lipid content than the control was obtained under salt stress compared to chemical stress induced by ETA and TEA, while the effect on lipid productivity was negligible. Thirty grams per liter of NaCl allowed to obtain the highest value of the total lipid content (30.33% DW) compared to the control (20% DW). FAME profile revealed a 97.50–98.99% composition in C16–C18 with no statistically meaningful differences among the three concentrations of salt and chemicals tested. The most represented fatty acids were C18:1 oleic (&gt; 45%wt), C16:0 palmitic (&gt; 34%wt), and C18:2 linoleic (&gt; 21%wt) obtained under 60 and 30 mg L−1 of NaCl and 0.150 g L−1 of ETA, respectively. When using 0.150 g L−1 of ETA, unsaturated fatty acids reached the highest portion (67.53%wt) than the control (62.26%wt). A quantitative and qualitative analysis of all FAMEs has been carried out to improve biodiesel properties. Chemical and physical properties of algal lipid–derived biodiesel showed a compliance with ASTM standards for unmixed biodiesel and the main European regulations (EN 14214 and EN 590) for the quality of biodiesel resulted fulfilled. Therefore, a profitable biodiesel can be obtained when cultivating C. zofingiensis under osmotic stress. Graphical abstract

Sustainable Biodiesel Production from a New Oleaginous Fungus, Aspergillus carneus Strain OQ275240: Biomass and Lipid Production Optimization Using Box–Behnken Design

Due to their low cost and ability to synthesize lipids for sustainable biodiesel production, oleaginous fungus has recently gained more prominence than other microorganisms. The new oleaginous fungus Aspergillus carneus OQ275240’s dry biomass, lipid content, and lipid yield were all optimized in this work, using the response surface methodology-based Box–Behnken design. Analysis of variance (ANOVA) was also used to examine the experimental data, and multiple regression analysis was used to fit the data to a second-order polynomial equation. Three independent variables, such as the concentration of yeast, glucose, and phosphorus, were examined for their mutual impacts. Maximum dry biomass (0.024 g/50 mL), lipid content (36.20%), and lipid yield (8.70 mg/50 mL) were achieved at optimal concentrations of 2.68 g/L of yeast, 20.82 g/L of glucose, and 0.10 g/L of phosphorus, respectively, showing that the actual data and predictions of the models were in good agreement. A. carneus OQ275240 has a favorable fatty acid profile that can be used to successfully create biodiesel, as shown by the presence of palmitic acid (C16:0), stearic acid (C18:0), and oleic acid (C18:1) in its fatty acid methyl esters (FAMEs) profile. Furthermore, the qualities of the biodiesel were investigated, and it was found that they fell within the parameters established by the international specifications EN 14214 (Europe) and ASTM D6751-08 (United States). These findings point to the newly evaluated filamentous fungal strain as a potential feedstock for the production of high-quality biodiesel.

Biodegradation of quinoline by Nitrosomonas mobilis Ms1 through nitrification: A mechanistic study

Effluents from pharmaceutical and coal gasification industries contain recalcitrant aromatic pollutants such as quinoline. Ammonia oxidizing bacteria (AOB) has been known to simultaneously oxidize ammonia and aromatic compounds. This study investigated the impact of quinoline, a nitrogen-containing heterocyclic aromatic compound, on nitrification by pure culture of AOB- Nitrosomonas mobilis Ms1. Quinoline has been found to inhibit nitrification to suspension culture by IC 50 value 40.01 μM. However, biofilm culture could withstand its inhibitory effect upto 50 μM. Morphological analysis of biofilm culture showed destruction in extracellularpolymeric substances (EPS) in the presence of quinoline at concentration of 1.5 mM and above. X-ray photoelectron spectroscopy (XPS) analysis of the biofilm surface showed loss of NH4+ peak in quinoline treated biofilm which indicated lower protein in EPS. Biodegradation analysis showed pyridine derivatives – 2,3-Pyridinedicarbonitrile, 2,4-Dicyanopyridine, and Pyridine, 2-[(3-methoxyphenyl) methyl] and hydroxylated aromatic such as 3-Hydroxy-4-methylbenzaldehyde and phenol, 4-[2-(methylamino) ethyl] as metabolic intermediates of quinoline degradation. These metabolic intermediates have been found to inhibit nitrification by blocking enzyme active site. Quinoline caused change in fatty acid methyl ester (FAME) profile which resulted in higher fraction of unsaturated FAME. This is one of the pioneer studies on quinoline biodegradation by a pure culture of AOB species, which could in turn aid to improve the efficacy of biological treatment of nitrogen-containing (heterocyclic compounds such as quinoline) wastewater.

Low-temperature thermal pre-treated sewage sludge for feeding of black soldier fly (Hermetia illucens) larvae: Protein, lipid and biodiesel profile and characterization

Previous work showed that low-temperature thermal pre-treatment of waste activated sludge (WAS) under different temperatures (30, 60, 75, 90 °C) and durations (2, 4, 8, 16 h) prior to black soldier fly larvae (BSFL) rearing could improve the larval growth. In this work, the biochemical profiles of WAS-fed BSFL and the characteristics of biodiesel produced were reported. The BSFL fed with pre-treated WAS had high protein contents (44%–54%) and moderate lipid contents (21%–25%). The WAS pre-treated at 90 °C for 16 h produced BSFL with the highest protein and lipid yields, achieving 69% and 71% of increments, respectively, as compared with the controlled WAS. Subsequently, high conversion of lipid into biodiesel (>90%) could be achieved through the acid-catalyzed transesterification process. The BSFL biodiesel was dominated by saturated fatty acid methyl esters (FAME), with C12:0 being the abundance. This unique FAME profile enabled BSFL biodiesel to have low iodine value, high cetane number and more oxidatively stable as compared with other reported biodiesels like palm oil and rapeseed oil biodiesels. The BSFL biodiesel also satiated the biodiesel standards of EN 14214 and ASTM D6751, except for the flash point, which was still higher and safer than petroleum diesel. In short, the thermal pre-treatment of WAS was effective in promoting BSFL growth and its lipid yield, ultimately leading to higher biodiesel production.

Prospecting the biofuel potential of new microalgae isolates

The continued search and urgent need for renewable fuel sources have necessitated the exploration of microalgae to identify relevant species for making biofuels. The aim of the study was bioprospecting and screening native microalgae strains from freshwater habitats of the Almaty region, Kazakhstan, to assess the potential for producing biofuel. The studied strains demonstrated simultaneous biomass productivity, lipid productivity, suitable fatty acid composition, and biodiesel properties. The sequence analysis of the ribosomal DNA internal transcribed spacer partial region and ribulose-bisphosphate carboxylase gene (rbcL) led to the identification of five microalgae: Monoraphidium griffithii ZBD-01, Nephrochlamys subsolitaria ZBD-02, Ankistrodesmus falcatus ZBD-03, Parachlorella kessleri ZBD-04, and Desmodesmus pannonicus ZBD-05. P. kessleri had the highest biomass production (1.42 ± 0.08 g L−1 day−1), lipid productivity (29 ± 1.2 g L−1day−1), and C16–C18 fatty acid contents (90%), followed by A. falcatus and M. griffithi. Gas chromatography/mass spectrometry analysis indicated that the dominant fatty acids in these strains were palmitic, stearic, and oleic acids. The calculated biodiesel properties of P. kessleri and A. falcatus based on fatty acid methyl esters (FAME) profiles showed relatively good fuel properties (cetane numbers - 48 and 50; iodine and saponification values - 83.4 and 103.6 g I₂/100 g oil, 260.8 and 199.5 mg KOH g−1), which correlate well with. Our results suggest that P. kessleri and A. falcatus are promising strains for biodiesel production due to their high lipid productivity, fatty acid profile with relatively high content of oleic acid, and suitable biodiesel properties. The isolated native species of microalgae from natural freshwater bodies of the Almaty region present opportunities for further exploitation for the sustainable production of biomass and biodiesel.