Lipid Yield Research Articles

Developing industry-scale microfluidization for cell disruption, biomolecules release and bioaccessibility improvement of Chlorella pyrenoidosa

To facilitate biomolecules extraction and bioaccessibility of Chlorella pyrenoidosa, a novel industry-scale microfluidization (ISM) was used to disrupt cells effectively. Microscope images showed ISM damaged cell integrity, disorganized cell wall structure, pulverized cell membrane and promoted the release of intracellular components. The decrease of particle size and the increase of ζ-potential also confirmed the cell disruption. The cell breakage ratio of sample treated at 120 MPa was 98%. Compared with untreated samples, total soluble solid content and protein extraction rate of the sample treated at 120 MPa increased by 2 °Brix and 12%. Protein was degraded by ISM, the release of intracellular protein and the reduction of molecular weight increased protein digestibility by 20% in in vitro gastric phase. Lipid yield and chlorophyll b content were also increased by ISM. These results provided a new solution to cell disruption of microalgae and expanded the application field of ISM.

Valorization of Kappaphycus alvarezii through extraction of high-value compounds employing green approaches and assessment of the therapeutic potential of κ-carrageenan

This study utilizes different emerging green extraction technologies to recover maximum value-added products from Kappaphycus alvarezii and evaluate their bio-functional properties. Using the supercritical fluid extraction (SFE) method, the total lipid yield of 0.21 ± 0.2 % was obtained from the biomass. Linoleic acid, eicosapentaenoic acid, arachidonic acid, γ-linolenic acid, and docosahexaenoic acid were present in higher concentrations (9.12 %) in the lipid extracted with SFE as compared to hexane (5.5 %). Using an ultrasonication assisted approach, ~56 % of κ-carrageenan was recovered from SFE residual biomass, which contains 28.5 ± 1.9 % sulfate content. It exhibited a monosaccharide content of 3,6-anhydrogalactose (~24 %) and galactose (~53 %), as well as rheological properties within FAO limitations that can be explored for food-grade applications. ~58 % of the total protein (12.5 %) from SFE residual biomass was recovered using subcritical water hydrolysis method. The effectiveness of κ-carrageenan in suppressing the 3CLpro of SARS-CoV-2 using in vitro and in silico approaches was investigated. κ-Carrageenan effectively inhibited the main protease by up to 93 % at 1.6 mg mL−1. In silico results revealed that κ-carrageenan successfully binds to the active site of the main protease while retaining the structural integrity and stability of protein-ligand complexes.

Sustainable mixotrophic microalgae refinery of astaxanthin and lipid from Chlorella zofingiensis

Microalgal astaxanthin possesses numerous bioactivities and has several health applications. The current research focuses on designing and optimizing the two-stage mixotrophic bioprocess by Chlorella zofingiensis for astaxanthin production. Gradual increase in light intensity (4-8k-lux) and 3x micronutrient concentration were the key parameters for maximizing biomass yield of 2.5 g/L during 15 days of stage I. Furthermore, stress conditions (excessive CO2, light, salinity, etc.) enhanced astaxanthin yield at stage II. 20k lux light, 3x nutrients, and 5% CO2 were the best ranges for maximum astaxanthin production. Maximum biomass yield and astaxanthin content were 3.3 g/L and 16.7 mg/g, respectively, after 29 days of bioprocess. Astaxanthin biosynthesis was also affected by salinity, but less than other parameters. Astaxanthin bioprocess resulted in enhanced lipid yields of 35–37%, which could be used for biodiesel. This study shows promising scale-up potential with attractive sustainability features of Chlorella zofingiensis model for commercial astaxanthin-lipid biorefinery.

Strategy for lipid extraction and transesterification to enhance Chlorella sorokiniana strain BV 12 feedstock utilization

Efficient production and recovery of fatty acid methyl esters (FAMEs) from lipid containing feedstock is the key step of biodiesel production. This enhances the utilization of feedstock and improves the final economics of the process. Currently, direct and indirect transesterification strategies are being employed for biodiesel production from microalgae with few reports of tailoring the process to a specific feedstock. In this study, Chlorella sorokiniana strain BV 12 was grown in modified BG-11 medium and biomass was harvested. This was subjected to different physical, chemical and physico-chemical strategies for increasing the transesterification yield. The transesterified lipid was evaluated for various biodiesel properties like iodine value, saponification value, acid value, peroxide value and cetane number. After harvesting, gravimetric lipid yield of 161.7 mg/g and 4117.5 µg/g of FAME were obtained. Extraction of lipid was dependent on the cell disruption technique as it is accumulated intracellularly as droplets. Sonication resulted in maximum FAME production using either dry (4724.2 µg/g) and wet (4835.8 µg/g) biomass which shows that wet biomass is more suitable for processing. Gravimetric results favour the extraction by sonication showing a 63.22% increase in lipid recovery. Testing of different solvents for extraction showed methanol as most favourable for FAME analysis with acidic catalyst like HCl and H2SO4 giving FAME with better ignition value (∼51, Cetane number).

Heterogeneous diacylglycerol acyltransferase expression enhances lipids and PUFA in Chlorella species

AbstractAlgae have been explored for renewable energy, nutraceuticals, and value‐added products. However, low lipid yield is a significant impediment to its commercial viability. Genetic engineering can improve the fatty acid profile of algae without compromising its growth. This study introduced the diacylglycerol acyltransferase (BnDGAT) gene from Brassica napus into Chlorella sorokiniana‐I, a fast‐growing and thermotolerant natural strain isolated from wastewater, which increased its intracellular lipid accumulation. Hygromycin‐resistant cells were selected, and enhanced green florescence protein fluorescence was used to distinguish pure transgenic cell lines from mixed cultures. Compared to the wild type, BnDGAT expression in transgenic C. sorokiniana‐I caused a threefold increase in non‐polar lipid and a twofold increase in polyunsaturated fatty acids. Nile red staining reaffirmed the presence of higher intracellular lipid bodies in transgenic cells. There was a substantial alteration in the fatty acid profile of transgenic alga expressing BnDGAT. The non‐essential omega 9 (C18: 1) fatty acid decreased (5%–7% from 18%), while alpha‐linolenic acid, an essential omega 3 fatty acid (C18: 3), was increased (23%–24% from 11%). This study substantiates a valuable strategy for enhancing essential omega‐3 fatty acids and neutral lipids to improve its nutritional value for animal feed. The increased lipid productivity should reduce the cost of producing fatty acid methyl esters (FAME). Improved FAME quality should address the clouding issues in cold regions.

Supercritical CO2 extraction of neutral lipids from dry and wet Chlorella vulgaris NIES 227 microalgae for biodiesel production

This study investigates supercritical CO2 extraction of neutral lipids from Chlorella vulgaris NIES 227 microalgae, for biodiesel applications. While microalgae feedstocks are typically desiccated before extraction, drying is energy intensive and supercritical extraction from wet microalgae would be beneficial in reducing overall energy costs. The effects on the supercritical extraction kinetics, yields and extract composition of the water content of the initial biomass (either 0 or 27 wt%), and of the operating pressure (200 and 250 bar) and temperature (40 and 60 °C) were investigated. The highest total extraction yield (16.16 wt% extract/dry biomass) was obtained with freeze-dried microalgae at 40 °C and 200 bar. However, the extracts obtained at 40 °C and 250 bar were the richest in fatty acids (0.96 g FA/extract), and the extracts obtained at 60 °C and 250 bar had the highest cetane number (69) and oxidative stability (18 h). Water in the initial biomass had a negative impact on total extraction yields (3.89 wt% extract/dry biomass at 200 bar and 40 °C) and led to increased pigment extraction, but results suggest the presence of water may promote the extraction of fatty acids, in particular monounsaturated ones, highly desirable for biodiesel. In comparison, Soxhlet extraction with hexane was found to have higher lipid yields (31.20 wt% extract/dry biomass) than any of the tested supercritical conditions, but more pigments were also extracted alongside, having a negative impact on oxidative stability. All the extracts obtained with supercritical CO2 and Soxhlet hexane met biofuel European standards for density, cetane numbers and iodine values.

Sequential extraction of value-added bioproducts from three Chlorella strains using a drying-based combined disruption technique

In this study, the sequential extraction of the three types of biochemicals from microalgae is employed, which is a more realistic and practical solution for large-scale extraction of bioproducts. The drying, grinding, organic solvent treatment, and ultra-sonication were combined to disrupt cells and sequentially extract bioproducts from three microalgae strains, Chlorella sorokiniana IG-W-96, Chlorella sp. PG-96, and Chlorella vulgaris IG-R-96. As the drying is the most energy-intensive step in cell disruption and sequential extraction, the effect of this step on sequential extraction deeply explored. The results show that total ash-plus contents of biochemicals in freeze-dried samples (95.4 ± 2.8%, 89.3 ± 3.9%, and 77.5 ± 4.2 respectively) are higher than those in oven-dried samples (91.0 ± 2.8%, 89.5 ± 3.0%, 71.4 ± 4.8%, respectively) showing the superiority of freeze drying over oven drying merely for Chlorella vulgaris IG-R-96 (p-value = 0.003) and non-significant variation for Chlorella sorokiniana IG-W-96 (p-value = 0.085) and Chlorella sp. PG-96 (p-value = 0.466). Variation among biochemical contents of strains is due to the difference in cell wall strength confirmed by TEM imaging. The freeze-dried samples achieved higher lipid yields than oven-dried samples. The total carbohydrate yields followed the same pattern. The extraction yields of total protein were higher in freeze-dried samples than in oven-dried. Total mass balance revealed that drying-based sequential extraction of value-added bioproducts could better demonstrate the economic potential of sustainable and renewable algal feedstock than independent assays for each biochemical.Graphical

Occurrence of fatty acids in Camellia genus: Extractions technologies and potential applications: A review

The Camellia genus (Theaceae) comprises more than 200 species, including the most famous Camellia sinensis (L.) Kuntze, Camellia oleifera Abel, and Camellia japonica (L.). The commercial interest in these plants linked to their seed fatty acid content increased in the last decades due to their quality and health-enhancing properties, which significantly depend on different aspects such as environmental conditions. Nowadays, the traditional extraction methods of fatty acids from camellias include mechanical press extraction and solvent extraction, which have a high environmental impact. Therefore, it is essential to develop extraction techniques to achieve the maximum lipid yield with the minimum environmental impact and cost. These innovative methods include enzymatic extraction, supercritical fluid extraction (SFE), microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE). However, they are often limited to the laboratory or pilot scale due to economic or technical bottlenecks. This article aims to explore recent advances and innovations related to the extraction of fatty acids from Camellia.

Bioconversion of Organic Wastes by Black Soldier Fly for Chitin, Lipid and Protein Production

The bioconversion of organic waste into black soldier fly (BSF) larvae, which is a valuable source of lipid, and protein, is part on an ongoing creative effort in valorising waste. Besides lipid and protein, BSF larvae also contain significant amounts of chitin, a polymer of N-acetylglucosamine that make up the backbone of the polysaccharide structure normally found in insects. In this study, the effects of organic waste type and moisture content on biomass conversion ratio were investigated. BSF larval development (larvae to prepupae to pupae) was found to occur to the highest extent (98.90 ± 0.71 % biomass converted) when kitchen waste (KW) was used compared to when vegetables waste (VW) (84.6 ± 1.41 % biomass converted) or fruit waste (FW) was used (87.5± 0.71 % biomass converted). The optimal moisture content of the kitchen waste was found to be 80 %, which results in the highest waste biomass conversion of 99.8 % ± 0.58. The BSF larvae were found to have approximately 38 – 42 % crude lipid, 34 – 41 % crude protein, and 8 – 9 % ash content. Chitin was isolated through a three-step process of deproteinization, demineralization, and decolorization. A yellowish-grey powder was obtained at the end of the isolation process and the chitin yield was determined to be 4 – 6% (g/g). Fourier transform infra-red (FTIR) analyses confirmed the chitin yield by identifying the -OH, -CH3CONH, and -CO stretching of its polysaccharides and glucosamine rings; and the lipid yield by noting the disappearance of the hydroxyl stretching that had been present in the spectra of unprocessed BSF larvae, and the appearance of X–H stretching which indicates the presence of triglyceride functional groups.

Detailed mechanistic investigation of stress-induced lipogenesis in oleaginous yeast for value-added metabolites

In the present study, a marine red yeast Rhodotorula glutinis ISO A1 cultivated under combinations of artificial seawater (ASW) and sewage wastewater (SWW) has been subjected to detailed mechanistic investigations via physiological and biochemical analysis to dissect the pathway of halotolerance behavior and carbon flux channelization towards enhanced lipid synthesis. Amid all tested groups (25–100% ASW), cells grown in 25% ASW yielded ∼ 1.4-fold higher lipid yield than glucose synthetic medium (GSM) and revealed metabolic rewiring of cells to channelize carbon pools for producing neutral lipids of vehicular quality. Detailed carbohydrate profiling showed enhanced glycerol, trehalose, mannose, and xylitol/arabitol under saline stress, suggesting the interplay of these metabolites to impart tolerance against osmotic imbalance. Further, the strengthened enzymatic activity (glutathione reductase, superoxide dismutase, ascorbate peroxidase) and non-enzymatic metabolites (betaine, proline) highlighted the active yeast defence network to counter altered redox state arise due to high salinity. The stress-induced responses also constituted substantial variations in membrane fluidity and production of biodiesel-quality lipids. Further findings like low thermal degradation temperature (at ∼ 265°C) and high chitin (can be converted into chitosan) entity in yeast de-oiled biomass primarily derived from yeast cells grown under contaminated environment; sea and sewage wastewater, signified its potential utilization for chitosan recovery, a commercially important product. Conclusively, this study elucidated a competent model of yeast-based biorefinery approach integrating seawater-wastewater utilization and simultaneous production of biodiesel and value-added products vital for a sustainable and circular bioeconomy.

Lipid extraction and analysis of microalgae strain pectinodesmus PHM3 for biodiesel production

The current study is focused on the lipid extract of microalgae; Pectinodesmus strain PHM3 and its general analysis in terms of chemical contents. Combinations of both chemical and mechanistic approaches were applied to obtain the maximum yield of lipids which was recorded to be 23% per gram through continuous agitation using Folch solution. The extraction methods used in this study included: Bligh and Dyers method, Continuous agitation method, Extraction using Soxhlet and Acid base extraction method. Lipid quantification of ethanol and Folch solution lipid extract was performed through gravimetric methods and qualification was done through Fourier Transmission Infrared Spectroscopy (FTIR) and Gas Chromatographymass spectrometry (GC-MS). Phytochemical analysis identified other compounds in ethanol extract and the results confirmed the presence of steroids, coumarins, tannins, phenols and carbohydrates. Transesterification of lipids showed 7% per gram dry weight yield of Pectinodesmus PHM3. GC-MS studies of extracted biodiesel suggested that 72% of biofuels was in the form of dipropyl ether, ethyl butyl ethers, methyl butyl ether and propyl butyl ether. Lipid processing of acid-base extract showed that oily nature of lipid shifted to a more precipitated form which is a common observation when mixture of lipids is converted to phosphatides.

Yield Enhancement of Valuable Lipid Compounds from Squid (Doryteuthis gahi) Waste by Ethanol/Acetone Extraction.

The study focused on the extraction of valuable lipid compounds from squid (Doryteuthis gahi) waste by a low-toxicity solvent mixture (ethanol/acetone, 50:50, v/v). The effect of the waste weight/solvent volume (WW/SV, g·mL-1) ratio and the number of extractions (NoE) on the total lipid (TL), phospholipid (PL), and tocopherol yields and on the fatty acid (FA) profile (eicosapentaenoic and docosahexaenoic acid contents; polyunsaturated FAs/saturated FAs and ω3/ω6 ratios) was investigated. As a result, an increased NoE led to an increased (p < 0.05) TL yield but a decreased (p < 0.05) proportion of PLs in the lipid extract. Additionally, a lower (p < 0.05) polyunsaturated FA/saturated FA ratio was detected by increasing the NoE. Some differences (p < 0.05) could be outlined as a result of increasing the WW/SV ratio; however, a definite trend for this extraction condition could not be concluded for any of the lipid parameters measured. Yield results were compared to those obtained by the conventional chloroform/methanol procedure. In order to attain an increased yield, the NoE required would depend on the polarity degree of the lipid molecule concerned. All ethanol/acetone extracting conditions tested led to remarkable yields for lipid compounds (PLs, α-tocopherol, ω3 FAs) and FA ratios with healthy, nutritional, and preserving properties.

Development of a green fermentation strategy with resource cycle for the docosahexaenoic acid production by Schizochytrium sp.

The fermentation production of docosahexaenoic acid (DHA) is an industrial process with huge consumption of freshwater resource and nutrient, such as carbon sources and nitrogen sources. In this study, seawater and fermentation wastewater were introduced into the fermentation production of DHA, which could solve the problem of fermentation industry competing with humans for freshwater. In addition, a green fermentation strategy with pH control using waste ammonia, NaOH and citric acid as well as FW recycling was proposed. It could provide a stable external environment for cell growth and lipid synthesis while alleviating the dependence on organic nitrogen sources of Schizochytrium sp. It was proved that this strategy has good industrialization potential for DHA production, and the biomass, lipid and DHA yield reached to 195.8 g/L, 74.4 g/L and 46.4 g/L in 50 L bioreactor, respectively. This study provides a green and economic bioprocess technology for DHA production by Schizochytrium sp.

UV mutagenesis followed by hydrogen peroxide treatment ameliorates lipid production and omega-3 fatty acids levels in Chlorella sp.

The high potential Chlorella sp. was obtained after the UV mutation which produces higher biomass and lipid content than the wild type. The lipid content and biomass were increased from 34 to 48 % dry cell weight and 1.42 to 1.97 g/L respectively. Further, hydrogen peroxide (H2O2) treatment increased both biomass and lipid content in mutant, whereas wild type did not show any considerable change in both biomass and lipid content. A 3-fold increase in total lipid yield was observed after the H2O2 treatment in mutant when compared to the untreated wild type. H2O2 treatment also altered the fatty acid composition of lipids resulting in enhanced eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) content. Overall results indicate that the strain improvement of Chlorella sp. by UV mutagenesis and oxidative stress by H2O2 treatment enhances the biomass and lipid content with high amounts of omega-3 fatty acids. Furthermore, the H2O2 treated mutant cells showed upregulation of the important genes involved in the fatty acid synthesis pathway.

Microalgae cultivation in stabilized landfill leachate for simultaneous treatment and biomass production

BackgroundThe high toxicity of landfill leachate has motivated to an investigation of economical and ecological treatment prior releasing into environment. Recently, microalgae have emerged as an alternative method due to its ability to recover nutrient and potential for bio-fuel production. However, the high concentrations of inhibitory compounds and ammoniacal nitrogen in young landfill leachates require high dilutions for microalgae to thrive. Hence, this study aims to evaluate the performance of microalgae by using stabilized landfill leachate with lower to no dilutions in nutrient removal, biomass and lipid production. MethodsLeachate concentrations of 33, 44, 66, 89 and 100 v/v% were initially treated with the microalgae C. vulgaris. Parameters of chemical oxygen demand (COD), ammoniacal nitrogen (NH3–N), orthophosphate (PO43−), total phosphorus (TP) and colour removal were evaluated. Cost analysis was conducted to evaluate the economical appropriateness. Significant findingsThe highest removals were achieved at 43.67% of COD, >97% of NH3–N, 79.26% of PO43−, 77.64% of TP and 44.04% of colour. Highest biomass yield obtained was 220 mg/L by 89 v/v% of leachate concentration with 8.14% of lipid yield. Cost of treatment was calculated to be ∼$0.02 per m3 leachate. The feasibility of stabilized landfill leachate treatment without any dilutions using microalgae was attained as they can survive amidst this condition, perform nutrient removals, and produce biomass simultaneously.

Potential xylose transporters regulated by CreA improved lipid yield and furfural tolerance in oleaginous yeast Saitozyma podzolica zwy-2-3

Lignocellulose's hydrolysate, a significant renewable source, contains xylose and furfural, making it challenging for industrial production of oleaginous yeast. On xylose fermentation with furfural treatment, OE::DN7263 and OE::DN7661 increased lipid yield and furfural tolerance versus WT, while, which of OE::CreA were decreased owing to CreA regulating DN7263 and DN7661 negatively. OE::CreA generated reactive oxygen species (ROS) causing oxidative damage. OE::DN7263, OE::DN7661, and ΔCreA reduced furfural via NADH; while ΔCreA produced less ROS and OE::DN7263, and OE::DN7661 scavenged ROS quickly, minimizing oxidative damage. Overall, CreA knockout increased DN7263 and DN7661 expression to facilitate xylose assimilation, enhancing NADH generation and ROS clearance. Finally, with mixed sugar fermentation, ΔCreA and OE::DN7263′s biomass and lipid yield rose without furfural addition, while that of ΔCreA remained higher than WT after furfural treatment. These findings revealed how oleaginous yeast zwy-2–3 resisted furfural stress and indicated ΔCreA and OE::DN7263 might develop into robust industrial chassis strains.

Screening the Lipid Production Potential of Oleaginous Yeast Yarrowia lipolytica under Wood Hydrolysates

Since Yarrowia lipolytica, an oily yeast, contains many valuable products as biomass, to increase its widespread use, it is very important to develop a sustainable production model. In this study, the production of high acid hydrolysate from sawdust biomass, which is produced in very high amounts in our environment, and the effect of these products on the growth efficiency of Yarrowia lipolytica were investigated. A preliminary statistical analysis was carried out to assess sugar production from sawdust by hydrolysis, which estimated 85% of total sugar recovery (TSR) using 96 g of sawdust, while TSR at the highest sawdust was as high as 79%. There was a higher loss in the recovery of C5 sugars with acid and time. This study revealed that Y. lipolytica could grow with high biomass yields in varying hydrolysate concentrations, approaching yields achieved in synthetic glucose media. The maximum biomass obtained was 13 and 26 g in batch and airlift operations, respectively, using organic nutrients. Biomass and lipid yields from kinetic modeling provided a close approximation to the experimental yields performed on an airlift reactor. It was found that Y. lipolytica biomass cultivated on sawdust hydrolysates had significant lipid and protein compositions, as high as 29 and 38%, respectively.

Cultivation of Microalgae Spirulina platensis Biomass Using Palm Oil Mill Effluent for Phycocyanin Productivity and Future Biomass Refinery Attributes

Palm oil mill effluent is a type of wastewater which contains a high concentration of organic nitrogen, phosphorus, and different supplement substances. These substances support and enhance the growth of microalgae. Cyanobacteria Spirulina platensis is a blue-green microalga with two phycobiliproteins as its primary constituents. Phycocyanin is a natural blue colourant used in biomedicines, cosmetics, diagnostics, treatments, and environmental protection. Chlorophyll pigment plays a significant role in photosynthesis where the photosynthetic process uses atmospheric carbon to produce starch and lipid which can eventually be converted into desirable products such as biodiesel. Therefore, in this study, Spirulina platensis was cultivated in different concentrations of diluted POME (10-50%, v / v ) at 26 ± 1 °C room temperature, 90 μmol photon m-2 s-1, and aerated for 24 h continuously. The growth of Spirulina platensis was monitored through optical density at 680 nm for 15 days. The highest biomass yield obtained in the control medium and 30% POME medium were 1.27 ± 0.02 and 1.16 ± 0.01 g/L, respectively. The highest phycocyanin yield obtained from the biomass harvested from 30% nutrient media was 175.12 ± 22.32 mg and followed by 163.55 ± 20.15 mg from control media with purified phycocyanin of 87.11 ± 5.20 mg and 85.31 ± 4.33 mg, respectively. The peak properties of phycocyanin such as the amide group at 1655.17 cm-1 (C=O stretching), FT-IR analysis revealed well-formed Spirulina platensis with all characteristic peaks and distinct fingerprints of phycocyanin. The ultrasound method produces the highest lipid yield ( 28.6 ± 0.7 %) which consists of stearic (38.45%), palmitoleic ( 25.72 ± 0.02 ), and palmitic ( 17.71 ± 0.04 ) fatty acid methyl esters. The FAME produced from the extracted lipid has the potential to be used in biodiesel applications. Since POME contains the essential nutrients which can support the growth of Spirulina platensis in the optimum environment for biomass and lipid productivity, it revealed the potential for biodiesel production.

Optimizing the subcritical water valorization of insect (Hermetia illucens l.) farming waste for biodiesel production

To counter the proliferation of secondary waste streams generated on insect (black soldier fly) farms, the present study integrated green water technology and acid-catalyzed transesterification as a basis to assess further value extraction potentials. By valorizing the waste streams, a process was developed to promote the circular economy paradigm. In this regard, wastes generated from a local insect farm were initially subjected to subcritical water extraction (SWE) for lipid recovery. The SWE process was optimized such that an enhanced lipid yield of 13.31 wt% was obtained at temperature, time, and solid loading conditions of 236.8 °C, 10 min of extraction, and 1 g/ 100 mL respectively. The lipids recovered were then subjected to an acid-catalyzed transesterification reaction for the production of a fatty acid methyl ester (FAME) mixture. A preliminary economic assessment of the process was also undertaken. The results showed that the wastes had the potential to be economically employed in the production of biodiesel that satisfied fuel property standards. In addition, the potential of employing the side streams as an animal feed was also highlighted due to the determined dominance of oligopeptides, which are known for their favorable bioactive properties. The results indicated that insect farming waste is a promising renewable source for high-quality biodiesel and animal feed production through the environmentally friendly biorefinery.

Coproduction of single cell protein and lipid from lignocellulose derived carbohydrates and inorganic ammonia salt with soluble ammonia recycling

Co-production of single cell protein (SCP) and lipid from lignocellulose-derived carbohydrates and inorganic ammonia offers a promising alternative for poultry or aquaculture feeds. An engineered oleaginous yeast Trichosporon cutaneum MP11 showed great potential for producing SCP and lipid from wheat straw and ammonia sulfate with minimum nutrient input. Trichosporon cutaneum MP11 showed stronger SCP and lipid fermentability using dry acid pretreated and biodetoxified wheat straw than using pure sugars. The residual ammonium sulfate in fermentation broth was recycled up to five times, resulting in ∼70% of nitrogen fixation into SCP. The overall yield of SCP and lipid from lignocellulose-derived sugars was 0.15 g/g and 0.11 g/g, respectively. This translates to the production of one ton of SCP (0.56 ton) and lipid (0.44 ton) from 6.6 tons of wheat straw, or one ton of SCP and lipid containing yeast cells (dry) from 4.8 tons of wheat straw.