Carotenoid Yield Research Articles

Carotenoid production by Formosa sp. KMW, a marine bacteria of Flavobacteriaceae family: Influence of culture conditions and nutrient composition

Abstract Exploitation of microbial sources for production of carotenoids is important as an alternative to synthetic carotenoids. The carotenoid production by microorganism is dependent on culture conditions and the nutrients. In this study, the carotenoid production by the marine bacteria Formosa sp. KMW belonging to Flavobacteriaceae family was evaluated under different growth conditions and nutrient composition. The yield of the total carotenoid produced increased with incubation time and the zeaxanthin content increased to 51.4±1.5% of total carotenoids after 6 days of incubation. The total carotenoid production was highest (0.97±0.03 mg/L) at pH 7.0. Carotenoid extract yield and carotenoid content were higher when the culture was grown under shaking condition under light. Significantly higher carotenoid production was observed in the absence of sugars (0.69±0.14 mg/L). The yield of carotenoid significantly (p

Effect of magnesium ion on crt gene expression in improving carotenoid yield of Rhodobacter sphaeroides.

This study aimed at increasing carotenoid yield of Rhodobacter sphaeroides in wastewater treatment by adding magnesium ion (Mg(2+)). Results showed that Mg(2+) could improve R. sphaeroides biomass and carotenoid yield effectively. The highest carotenoid yield of 4.83 ± 0.14 mg/g biomass and biomass production of 3900 ± 180 mg/L were achieved at optimal Mg(2+) concentration of 15 mmol/L. Mechanism analysis revealed that Mg(2+) could promote carotenoid production by regulating the expressions of crt genes. Up-regulation of crtBDA genes improved carotenoid biosynthesis of R. sphaeroides.

Ultrasonic‐Assisted Solvent Extraction of Carotenoids From Rapeseed Meal: Optimization Using Response Surface Methodology

AbstractUltrasound‐assisted solvent extraction of carotenoids from rapeseed meal was investigated and evaluated by response surface methodology. We have compared the yields of carotenoids by using five different solvent systems, and found that the highest yield can be achieved under petroleum ether/acetone (v/v = 1/1). We have further tested the effect of ultrasonic power, modulation frequency, duration, temperature, liquid to material ratio and extraction times on the yield of carotenoids by adopting Plackett–Burman and Box–Behnken experimental design methods. Optimal conditions for obtaining high yield of carotenoids were as follows: temperature 49.6C, liquid to material ratio 41.4 mL/g, duration 48.5 min, ultrasonic power 252.9 W (240 W was used in the control experiments). Under the above conditions, average carotenoid yield was 0.1577 ± 0.0014 mg/g, and the extraction percentage was 79.61 ± 0.71%. The results indicated that rapeseed meal was a promising alternative source for carotenoid extraction.Practical ApplicationsCarotenoids are one of the most common natural food colorants and exist widely in plants, bacteria, fungi and animals. Ultrasound has been utilized to assist the solvent extraction of bioactive compounds from vegetal materials, and led to high yield of desired products. In the present study, we have investigated ultrasound‐assisted extraction of carotenoids from rapeseed meal using the response surface methodology. In order to obtain the highest yield of carotenoids, we have examined various operational parameters, such as extraction temperature, liquid to material ratio, solvent composition, extraction time and modulation frequency, and have established optimal conditions to extract carotenoids from rapeseed meal. Our results provide basic knowledge on the extraction of carotenoids from rapeseed meal, which serves as a promising bioresource.

Overexpression of ZWF1 and POS5 improves carotenoid biosynthesis in recombinant Saccharomyces cerevisiae.

Recombinant Saccharomyces cerevisiae expressing exogenous carotenogenic genes can synthesize carotenoids. NADPH is a key cofactor for carotenoid biosynthesis, while glucose-6-phosphate dehydrogenase (Zwf1) and an NADH kinase (Pos5) are the two main NADPH-supplying sources in S.cerevisiae. Here, the effect of ZWF1 and POS5 overexpression on carotenoid yield in recombinant S.cerevisiae was explored. The initial carotenogenic strain Sc-EYBIH+I which expressed crtE, crtYB, crtI, cHMG1 and another copy of crtI could synthesize 1·35±0·13mgl(-1) of lycopene and 0·32±0·02mgl(-1) of β-carotene. When ZWF1 was overexpressed (Sc-EYBIZH+I), glucose-6-phosphate dehydrogenase activity increased by 103-fold, the transcription level of crtE and crtI increased significantly, the lycopene and β-carotene yield increased to 2·29±0·06 and 0·38±0·02mgl(-1) respectively. When POS5 was overexpressed (Sc-EYBIPH+I), NAD kinase activity increased by 5·5-fold, the transcription level of crtE, crtYB and crtI increased obviously, the lycopene and β-carotene yield increased to 2·50±0·11 and 0·53±0·03mgl(-1) respectively. Therefore, improvement of NADPH supply contributed to carotenoids biosynthesis in S.cerevisiae and overexpression of POS5 was more effective than overexpression of ZWF1. This study provides a new strategy for enhancing carotenoid biosynthesis. NADPH is a key cofactor for carotenoid biosynthesis. Glucose-6-phosphate dehydrogenase (Zwf1) and an NADH kinase (Pos5) are effective NADPH-supplying sources in Saccharomyces cerevisiae. When ZWF1 and POS5 were overexpressed in a carotenoid-producing S.cerevisiae strain individually, the total yield of lycopene and β-carotene increased by 59·9% and 81·4%, respectively, and the final product β-carotene yield increased by 18·8% and 65·6% respectively. This suggests the improvement of NADPH supply as a useful strategy for carotenoids biosynthesis.

Modification of targets related to the Entner-Doudoroff/pentose phosphate pathway route for methyl-D-erythritol 4-phosphate-dependent carotenoid biosynthesis in Escherichia coli.

BackgroundIn engineered strains of Escherichia coli, bioconversion efficiency is determined by not only metabolic flux but also the turnover efficiency of relevant pathways. Methyl-d-erythritol 4-phosphate (MEP)-dependent carotenoid biosynthesis in E. coli requires efficient turnover of precursors and balanced flux among precursors, cofactors, and cellular energy. However, the imbalanced supply of glyceraldehyde 3-phosphate (G3P) and pyruvate precursors remains the major metabolic bottleneck. To address this problem, we manipulated various genetic targets related to the Entner–Doudoroff (ED)/pentose phosphate (PP) pathways. Systematic target modification was conducted to improve G3P and pyruvate use and rebalance the precursor and redox fluxes.ResultsCarotenoid production was improved to different degrees by modifying various targets in the Embden–Meyerhof–Parnas (EMP) and ED pathways, which directed metabolic flux from the EMP pathway towards the ED pathway. The improvements in yield were much greater when the MEP pathway was enhanced. The coordinated modification of ED and MEP pathway targets using gene expression enhancement and protein coupling strategies in the pgi deletion background further improved carotenoid synthesis. The fine-tuning of flux at the branch point between the ED and PP pathways was important for carotenoid biosynthesis. Deletion of pfkAB instead of pgi reduced the carotenoid yield. This suggested that anaplerotic flux of G3P and pyruvate might be necessary for carotenoid biosynthesis. Improved carotenoid yields were accompanied by increased biomass and decreased acetate overflow. Therefore, efficient use of G3P and pyruvate precursors resulted in a balance among carotenoid biosynthesis, cell growth, and by-product metabolism.ConclusionsAn efficient and balanced MEP-dependent carotenoid bioconversion strategy involving both the ED and PP pathways was implemented by the coordinated modification of diverse central metabolic pathway targets. In this strategy, enhancement of the ED pathway for efficient G3P and pyruvate turnover was crucial for carotenoid production. The anaplerotic role of the PP pathway was important to supply precursors for the ED pathway. A balanced metabolic flux distribution among precursor supply, NADPH generation, and by-product pathways was established.Electronic supplementary materialThe online version of this article (doi:10.1186/s12934-015-0301-x) contains supplementary material, which is available to authorized users.

Enhancement of carotenoid production in the new carotenoid-producing photosynthetic bacterium Rhodopseudomonas faecalis PA2

Use of photosynthetic bacteria to produce carotenoids has increased considerably in recent decades; however, few studies have been conducted to identify additional carotenoid producers. In this study, Rhodopseudomonas faecalis PA2 was shown to be capable of carotenoid production, and factors influencing this production were identified. The maximum carotenoid content was observed at an initial pH of 7 in the presence of 0.8% malic acid, 0.4% yeast extract, and 0.05% Fe3+ under light at 4,000 lux. Fe3+ significantly enhanced carotenogenesis, resulting in a production rate of 2.5 mg/g/day and a reduction in time to maximum production from 12 to 8 days. The carotenoid content and carotenoid yield under modified conditions were 413 mg/L and 13 mg/g (mg total carotenoids per gram of dry cells), respectively, representing an increase of 117% relative to the original condition. The biomass and carotenoid productivity reached 4 g/L/day and 51.6 mg/L/day, respectively. To the best of our knowledge, this is the first study of carotenoid production by Rps. faecalis PA2. The results indicated that the productivity of this organism under the aforementioned conditions was comparable to that of previously described purple photosynthetic bacterial species.

Rapid and environmentally-friendly extraction of carotenoids from Blakeslea trispora.

A rapid and environmentally-friendly method of carotenoid extraction from Blakeslea trispora was performed using low-pressure steam explosion for cell disruption and ethyl lactate for the extraction. Response surface methodology determined the optimal extraction conditions to obtain the maximum carotenoid yield. These optimal conditions consisted of low-pressure steam explosion at 0.2MPa for 4.4min, followed by extraction with ethyl lactate at a ratio of 1:25 at 39°C for 45min. Optimal technology was used, and the total carotenoid yield reached 95.6%. In contrast to previously methods, the time-consuming drying process was eliminated and the extraction time was significantly decreased. Ethyl lactate is an environmentally-friendly solvent with low toxicity in this method.

Enzyme-Aided Extraction of Carotenoids from Pumpkin Tissues

Carotenoids are the most common pigments in nature possessing high nutraceutical value. The objective of the present work was to obtain a good yield of carotenoids from pumpkin tissues, using cellulase and pectinase enzymes. Various parameters such as concentration of enzymes and time of incubation were optimised, to improve the yield of carotenoid from pumpkins. Enzyme-aided extraction of carotenoid from whole pumpkins under optimised conditions resulted in an increase in the carotenoid yield by 33.3% (w/w) in cellulase-treated sample and 28.6% (w/w) in case of pectinase-treated sample. Extraction from pumpkin peel under optimised conditions showed a remarkable increase in the yield of carotenoid by 77.7% (w/w) and 71.4% (w/w), for cellulase- and pectinase-treated samples, respectively.

Extraction of Minor Compounds (Chlorophylls and Carotenoids) from Yarrow–Rose Hip Mixtures by Traditional versus Green Technique

AbstractNowadays, various branches from food industry generate large amount of by‐products that are often underutilized, which could have negative environmental impact and increase the price of the raw material as it is not completely utilized in the production. Mixtures of two interesting plants (yarrow and rose hip) with different ratios, obtained as by‐products from filter‐tea factory, have been extracted with organic solvents and with environmentally friendly technology, supercritical fluid extraction (SFE). In the obtained extracts, quantitative content of minor plant pigments (chlorophylls and carotenoids) was determined and technologies were compared. Moreover, the effect of SFE parameters on yields of chlorophylls and carotenoids was determined. The results showed that SFE could be used as a good alternative for extraction of plant pigments from Achillea millefolium L. and Rosa canina L. mixtures. Besides plant pigments, the obtained extracts were rich in other nonpolar compounds from plant mixtures. Utilization of herbal waste provided value‐added products, rich in various health benefit compounds.Practical ApplicationsCurrently, there is growing interest for developing economically feasible and environmentally friendly processes for extraction of bioactive compounds from plant material. Moreover, sustainable and relatively cheap raw material should be utilized in the production. Therefore, waste and by‐products from the food industry, e.g., plant material from filter‐tea factory with small mean particle size, could be used. Traditional technologies used for extraction of chlorophylls and carotenoids are no longer environmentally acceptable and alternative green technologies, such as supercritical fluid extraction, should be considered. This research provides a comparison of green and traditional processes for plant pigment extraction and studies effects of process parameters (pressure and temperature) on yields of the investigated compounds. It also utilizes by‐products of two medicinal plants (yarrow and rose hip) as raw material for extraction as herbal dust generated in filter‐tea factory could not be used for tea bags filling.

Enhancement of Rhodobacter sphaeroides growth and carotenoid production through biostimulation

Bacillus thuringiensis/cereus L2 was added as a biostimulant to enhance the biomass accumulation and carotenoid yield of Rhodobacter sphaeroides using wastewater as the culturing medium. Results showed that biostimulation could significantly enhance the R. sphaeroides biomass production and carotenoid yield. The optimal biostimulant proportion was 40μL (about 6.4×105CFU). Through the use of biostimulation, chemical oxygen demand removal, R. sphaeroides biomass production, carotenoid concentration, and carotenoid yield were improved by 178%, 67%, 214%, and 70%, respectively. Theoretical analysis revealed that there were two possible reasons for such increases. One was that biostimulation enhanced the R. sphaeroides wastewater treatment efficiency. The other was that biostimulation significantly decreased the peroxidase activity in R. sphaeroides. The results showed that the highest peroxidase activity dropped by 87% and the induction ratio of the RSP_3419 gene was 3.1 with the addition of biostimulant. The enhanced carotenoid yield in R. sphaeroides could thus be explained by a decrease in peroxidase activity.

Response surface methodology toward the optimization of high-energy carotenoid extraction from Aristeus antennatus shrimp

High-energy assisted extraction techniques, like ultrasound assisted extraction (UAE) and microwave assisted extraction (MAE), are widely applied over the last years for the recovery of bioactive compounds such as carotenoids, antioxidants and phenols from foods, animals and herbal natural sources. Especially for the case of xanthophylls, the main carotenoid group of crustaceans, they can be extracted in a rapid and quantitative way with the use of UAE and MAE.Response surface methodology (RSM) is used for the optimization of extraction methodologies, also being applied to optimize high energy techniques. Three independent variables, namely extraction time, ultrasound or microwave power and solvent/material ratio, were investigated for both methods by employing a 16-run three-level Box–Behnken design (BBD). Considering the extraction efficiency for carotenoids from Aristeus antennatus shrimp, the selected conditions for UAE were 5min, 600W and 10:1mLg−1. Acetone was the solvent of choice for the extraction procedure. For MAE, the best experimental values were 7min, 30W and 20:1mLg−1 using n-hexane:acetone:ethanol 2:1:1 (v/v/v) as extraction solvent. The determination of total carotenoid yield was carried out using the spectophotometric calibration curve (A=0.1646(±0.0061)C−0.005(±0.022), R2=0.996, n=3) of a standard mix solution of canthaxanthin, zeaxanthin and lutein at 452.1nm. Under the selected conditions, the yield of total carotenoids for UAE was 23.4(±2.3) and 6.73(±0.56)mg of carotenoids per 100g dry sample for the head and the body of shrimp, while for MAE was 23.92(±0.63) and 13.3(±1.1)mg of carotenoids per 100g dry sample, respectively. The recovery of both methods was calculated between 60 and 105%. The results indicate that high-energy extraction techniques are faster, less laborious, more repeatable and reproducible methods than the conventional approaches for the quantitative recovery of sensitive bioactive compounds. Moreover, the recovery of a high-added value group of bioactive molecules from natural sources, such as carotenoids, can constitute a profitable and valuable commercial alternative, as these compounds can be used as dietary supplements, food color enhancers and additives in animal feeds, functional foods, preservatives, pharmaceuticals and cosmetics.

Pressurized liquid extraction and low-pressure solvent extraction of carotenoids from pressed palm fiber: Experimental and economical evaluation

In this work, a comparison of Soxhlet extraction (LPSE–SOX), percolation (LPSE–PE) and pressurized liquid extraction (PLE) for the recovery of carotenoid-rich extracts from pressed palm fiber (PPF) was carried out in terms of yield, carotenoid profile and economic viability to evaluate the methods’ industrial applicability. An optimization study was performed for each extraction technique with ethanol at a solvent/feed ratio of 20. The independent variables were temperature (35–55°C), pressure (0.1–8MPa) and flow rate (1.6, 2.4g/min). The results showed that the global extraction yield obtained using LPSE–SOX (96±4mg extract/g PPF d.b.) after 6h was higher than that obtained using LPSE–PE (74±5mg extract/g PPF d.b., 35°C, 2.4g/min) or PLE (44±3mg extract/g PPF d.b., 55°C, 4MPa, 2.4g/min) after dynamic extraction time of 17min under optimized conditions. On the other hand, the carotenoid yield obtained using PLE (305±18μg α-carotene/g extract and 713±46μg β-carotene/g extract) was higher than the obtained by LPSE–SOX (142±13μg α-carotene/g extract and 317±46μg β-carotene/g extract). PLE technique showed the highest selectivity for carotenoids than LPSE techniques. The lowest cost of manufacturing (COM) were obtained for LPSE–PE and PLE with values of US$13.4 and US$29.2/kg extract for a 0.5m3 vessel capacity.

Influence of green solvent extraction on carotenoid yield from shrimp (Pandalus borealis) processing waste

In this work, sunflower oil (SF) and methyl ester of sunflower oil (ME-SF) were introduced as two green solvents for extracting astaxanthin (ASX) from shrimp processing waste. The effects of temperature (25, 45, 70°C), solvent to waste ratio (3, 6, 9), waste particle size (0.6 and 2.5mm) and moisture content (0% and 86.8%) as well as stirrer speed (120, 200, 400rpm) were studied during the process. In all the experiments, ASX yields from extraction with ME-SF were higher than with SF. For both solvents, the highest ASX content using a short extraction time was achieved at a temperature of 70°C, a solvent to waste ratio of 9 and a stirrer speed of 400rpm while the waste particle size and moisture content were 0.6mm and 86.8%, respectively. ME-SF and SF seem promising solvents extracting respectively about 80% and 60% of the total ASX extracted by organic solvents.

Effect of biomass concentration on secondary carotenoids and triacylglycerol (TAG) accumulation in nitrogen-depleted Chlorella zofingiensis

The effect of biomass-specific photon absorption rate on triacylglycerol (TAG) and secondary carotenoid yield was studied. Chlorella zofingiensis (Chlorophyta) was cultivated batch-wise with sufficient initial nitrogen to produce 2.5, 3.4 and 4.1gL−1 prior to nitrogen depletion, which resulted in biomass-specific photon absorption rates of 4.7, 3.5 and 2.9μmolphg dry weight−1s−1, respectively. During nitrogen starvation, the TAG as well as secondary carotenoid yield on light did not differ between the cultures, which indicates that in the studied range the biomass-specific photon absorption rate did not affect the amounts of energy used for TAG and secondary carotenoid production. The maximal TAG yield on light (320mgmolph−1) was higher than values reported before for microalgae. Besides, for the first time the secondary carotenoid yield on light was reported (maximally 2.75mgmolph−1).

Comparative study of the extraction methods for recovery of carotenoids from algae: extraction kinetics and effect of different extraction parameters

AbstractCarotenoid extraction from algae is currently under intensive research due to the increased demand for naturally occurring compounds, which are especially rich in biologically active isomers. Furthermore, natural carotenoids exhibit greater stability than synthetic ones. Conventional liquid extraction suffers from several drawbacks, such as use of high amounts of solvent, and several extraction steps. In this work carotenoid extraction from algae using different methods, such as microwave and ultrasound assisted extraction as well as pressurized liquid extraction and extraction with supercritical CO2 and ethane, is summarized together with modelling of extraction kinetics. In addition carotenoid availability, algae pretreatment, stability of extracts, their antioxidative and antimicrobial activities as well as downstream processing and storage of algae extracts have been reviewed. As a conclusion it can be stated that carotenoid extraction is complex, demanding optimization of the carotenoid yield and antioxidative stability, which are often inversely proportional. © 2014 Society of Chemical Industry

Effect of pulsed electric field processing on carotenoid extractability of carrot purée

SummaryThe purpose of this research was to study the effect of electric field strength (0.1–1 kV cm−1) and frequency (5–75 Hz) during pulsed electric field (PEF) processing on the extractability of carotenoids in carrots, which was examined using different vegetable oils. Increasing electric field strengths up to 1 kV cm−1 at 5 Hz significantly (P < 0.05) increased the extraction of carotenoids from carrot pomace. Increasing frequency above 10 Hz at 1 kV cm−1 did not improve the carotenoids extraction. The yield of carotenoids extracted was dependent on the vegetable oils. Sunflower and soya bean oils had the highest carotenoid extractability, and peanut oil was the lowest for carrot pomace treated at 0.6 kV cm−1 and 5 Hz, but no significant difference was observed among vegetable oils for carrot pomace treated at 50 Hz. This study suggests that PEF can improve the carotenoids extractability of carrots depending on the electric field strength and frequency used.

Co-solvent selection for supercritical fluid extraction of astaxanthin and other carotenoids from Penaeus monodon waste.

In recent years, astaxanthin is claimed to have a 10 times higher antioxidant activity than that of other carotenoids such as lutein, zeaxanthin, canthaxanthin, and β-carotene; the antioxidant activity of astaxanthin is 100 times higher than that of α-tocopherol. Penaeus monodon (tiger shrimp) is the largest commercially available shrimp species and its waste is a rich source of carotenoids such as astaxanthin and its esters. The efficient and environment-friendly recovery of astaxanthins was accomplished by using a supercritical fluid extraction (SFE) technique. The effects of different co-solvents and their concentrations on the yield and composition of the extract were investigated. The following co-solvents were studied prior to the optimization of the SFE technique: ethanol, water, methanol, 50% (v/v) ethanol in water, 50% (v/v) methanol in water, 70% (v/v) ethanol in water, and 70% (v/v) methanol in water. The ethanol extract produced the highest carotenoid yield (84.02 ± 0.8 μg/g) dry weight (DW) with 97.1% recovery. The ethanol extract also produced the highest amount of the extracted astaxanthin complex (58.03 ± 0.1 μg/g DW) and the free astaxanthin content (12.25 ± 0.9 μg/g DW) in the extract. Lutein and β-carotene were the other carotenoids identified. Therefore, ethanol was chosen for further optimization studies.

Extraction and Stability of Carotenoid-Containing Lipids from Hepatopancreas of Pacific White Shrimp (Litopenaeus vannamei )

Impacts of extraction conditions on lipid and carotenoid yields from hepatopancreas of Pacific white shrimp (Litopenaeus vannamei) were investigated. Among single solvents (acetone, isopropanol and hexane) and their mixtures, a mixture of hexane and isopropanol (50:50, v/v) rendered lipids with the highest carotenoid yield (336.40 mg/kg hepatopancreas) with the extraction yield of 18.22% (w/w hepatopancreas) (P < 0.05). The use of hepatopancreas to solvent ratio of 1.0:4.5 (w/v) and three repetitions showed the highest carotenoid yield (363.94 mg/kg hepatopancreas) with the extraction yield of 18.08% (w/w hepatopancreas). Astaxanthin, astaxanthin diester and canthaxanthin were the major carotenoids found in lipids. When astaxanthin (2 mg/g lipid) was added into lipid, the oxidation was lowered, in comparison with the control during the storage at 30C for 10 days as indicated by lower ρ-anisidine value. Fourier transform infrared spectra study also revealed that triglyceride in lipids underwent oxidation to a lower degree when astaxanthin was incorporated. Practical Applications Shrimp hepatopancreas, a by-product from shrimp-processing industries, is one of the important sources of lipids and natural carotenoids, which are susceptible to oxidation. Their changes are associated with development of off-odor and loss in nutritive value. The recovery of lipid and carotenoid from hepatopancreas by an appropriate means would increase the revenue for shrimp-processing industries. Additionally, those value-added products could serve as the excellent source of nutrients as well as bioactive compounds.

Draft Genome Sequence of Deinococcus xibeiensis R13, a New Carotenoid-Producing Strain.

Deinococcus xibeiensis strain R13, isolated from radiation-contaminated soils, synthesizes a unique ketocarotenoid, deinoxanthin. Here, we present a 3.49-Mb assembly of its genome sequence, which can help us find the key genes of the deinoxanthin biosynthesis pathways and modify genes obtaining a high yield of the new carotenoid.

Extraction of lipids and pigments of Chlorella vulgaris by supercritical carbon dioxide: influence of bead milling on extraction performance

The influence of bead milling on the extraction of lipids and pigments by supercritical carbon dioxide was investigated in this study. Different operating parameters for the 3-h process were first tested on raw Chlorella vulgaris; 600 bar was the optimum pressure at 60 °C with a carbon dioxide flow rate of 30 g min−1. Under these operating conditions, 10 % of total lipid containing chlorophyll and carotenoids with 1.61 and 1.72 mg g−1 dry weight of microalga, respectively, has been recovered. Microscopic observation was used to assess a cell wall breakage through bead milling, which produced positive results in terms of increasing the yield of biomolecules of interest. Thus, under the same operating conditions, the yield of total lipid extract, chlorophyll and carotenoids increased significantly. Moreover, the addition of a polar co-solvent to a raw microalga had a considerable effect on the final extract. Overall, the addition of 5 % w v−1 ethanol to a raw microalga increased the total extract yield by 27 %, and bead milling increased the total extract yield by 16 %. Chlorophyll and carotenoids were also significantly affected by the addition of ethanol, with an 81 and 65 % increase with a raw microalga and a 61 and 52 % increase using bead milling, respectively.