Table 2 - uploaded by Tong Wang
Content may be subject to copyright.
Effect of IPA concentration, sonication, and extraction times on the oil extraction yield

Effect of IPA concentration, sonication, and extraction times on the oil extraction yield

Source publication
Article
Full-text available
An efficient process for fractioning microalgae oil and non-lipid biomass was developed. Isopropyl alcohol (IPA) was used to extract oil from Nannochloropsis sp. at 80 °C, leaving the majority of non-lipid biomass in the solid fraction. The effectiveness of extraction with or without a dewatering pretreatment (DW) was compared. Effects of dewaterin...

Contexts in source publication

Context 1
... yield values (calculated from theoretical oil content) of various treatments are shown in Table 2. In spite of the large variation, the double extractions all had higher yields compared to the single extraction, and the difference ran- ged from 4 to 37 %. ...
Context 2
... may be one of the reasons that the 95 % IPA did not extract more oil than 88 or 70 % IPA when intact cells were used. The large variation of the oil yields as seen in Table 2 likely resulted from the inaccurate estimation of moisture content of the material used for each replicate. The solid content of algae was only measured a few times during the experiments because of the limited amount of sample. ...

Similar publications

Article
Conductance measurements of vanadyl sulfate have happened in binary mixed solvent with alcohol mass fraction 0%, 30% and 50% (W/W) (EtOH-H2O) at different temperatures from 298.15 to 313.15 K (with a step of 5 K). The experimental data have been analyzed by using the Fuoss-Hsia-Fernández-Prini (FHFP) equation. Molar conductance (Λm), limiting molar...

Citations

... In fact, proteins are located in the cytoplasm, thus, their extraction from the cellular matrix into the surrounding medium could be prevented by the rigidity of cell wall as a result of the presence of high concentration of polar lipids (glycolipids and phospholipids). The use of chloroform-methanol mixtures could completely extract lipids, including structural lipids as phospholipids and glycolipids responsible for the regulation of cellular membranes fluidity and function [41][42][43]. The extraction of polar lipids could enable the whole formation of the microalgae cell membrane which facilitates the proteins release [20]. ...
Article
Full-text available
Microalgae fractionation was investigated combining supercritical carbon dioxide extraction of lipids and pigments and protein extraction from the residues, on Chlorella vulgaris and Nannochloropsis oculata. The results indicated that for N. oculata, chlorophyll (a) is extracted rapidly and selectively apart from Chlorophyll (b), representing 34% and 0.41% in 30 min at 450 bar and 50 °C and up to 43% and 0.48% at 750 bar at the same time and temperature, respectively. The extraction profile of chlorophyll (a) is similar to of neutral lipids. For C. vulgaris, the results emphasized the importance of adding a co-solvent during the supercritical extraction to achieve 30% of chlorophyll (a), while the extraction of other pigments was lower especially for chlorophyll (b) extraction yield reaching 0.1% of its total content. Then for the second time, the extraction of proteins was studied on N. oculata delipidated cake. The results showed that the higher the level of delipidation, the higher the extraction yield, with an increase from 54% for crude cake to 73% for delipidated cake.
... The comparison of growth rate and dry mass of isolated strains gave different results at different concentrations of ascorbic acid and Iron III chloride, FeCl 3 (0, 1, 2.5, 5, and 10 µM) for each strain. Test for their lipid production showed that the C. sorokiniana strain 1 gave maximum growth at a concentration of 2.5 µM of that of ascorbic acid and FeCl 3 (Yao et al. 2012). C. sorokiniana strain 2 gave maximum growth at the same concentration of ascorbic acid but it was inhibited by the addition of FeCl 3 . ...
... C. sorokiniana strain 2 gave maximum growth at the same concentration of ascorbic acid but it was inhibited by the addition of FeCl 3 . For strain 3 maximum growth was observed at a 2 & 5 µM ascorbic acid (Yao et al. 2012), while it was inhibited by the addition of FeCl 3 in case of 3 rd strain. The reason in case of ascorbic acid is the metabolic gene ascorbate which enhance the biomass production (Zalogin 2012), triggers the metabolic genes involved in the production of biomass. ...
Article
Rising oil prices and climate change have resulted in more emphasis on research into renewable biofuels. In this study, different water samples were collected from local vicinities for the isolation of local isolates of microalgae to check their potential towards the production of biofuel by the addition of different chemical substrates. Five different concentrations of ascorbic acid and iron (III) chloride (0, 1, 2.5, 5 & 10 µM) are used as substrates. Microscopic analysis evaluated that samples belong to genus Chlorella and further molecular identification showed that the samples are C. sorokiniana. Among all the concentrations of ascorbic acid 2.5 µM is most effective against the C. sorokiniana strain 1 (Safari Wildlife Park, Lahore) and C. sorokiniana strain 2 (Bahria Town, Lahore) while C. sorokiniana Strain 3 (SukhChane Society, Lahore) responded at 2.5 & 5 µM in term of biomass production. FeCl3 (2.5 µM) is effective against C. sorokiniana strain 1 while the growth of C. sorokiniana strain 2 and C. sorokiniana Strain 3 is inhibited. Lipid content analysis showed that only the C. sorokiniana strain 1 shows effective results at 1 & 2.5 µM of ascorbic acid and FeCl3, respectively. Those concentrations which give the significant results of lipid production were preceded for fatty acid profiling. Results indicate that the C. sorokiniana strain 1 can be considered as a source of alpha-linolenic acid; the basic constituent of biofuel production. In this study, it is concluded that C. sorokiniana strain 1 is useful for the production of environment friendly biofuel.
... Navarro López et al. using only ethanol were able to successfully extract lipids from wet Nannochloropsis gaditana [58], whereas in this study using a similar methodology (extraction system C) only 30% of the total lipids were extracted. Yao et al. also reported an effective usage of isopropanol as lipid solvent from Nannochloropsis sp. at 80 °C [59]. The same authors state that elevated temperatures favor extractions with alcohol. ...
Article
Full-text available
Background Microalgae have attracted considerable interest due to their ability to produce a wide range of valuable compounds. Pulsed Electric Fields (PEF) has been demonstrated to effectively disrupt the microalgae cells and facilitate intracellular extraction. To increase the commercial viability of microalgae, the entire biomass should be exploited with different products extracted and valorized according to the biorefinery scheme. However, demonstrations of multiple component extraction in series are very limited in literature. This study aimed to develop an effective lipid extraction protocol from wet Scenedesmus almeriensis after PEF-treatment with 1.5 MJ·kg DW ⁻¹ . A cascade process, i.e., the valorization of several products in row, was tested with firstly the collection of the released carbohydrates in the water fraction, then protein enzymatic hydrolysis and finally lipid extraction. Biomass processed with high pressure homogenization (HPH) on parallel, served as benchmark. Results Lipid extraction with ethanol:hexane (1:0.41 vol/vol) offered the highest yields from the different protocols tested. PEF-treatment promoted extraction with almost 70% of total lipids extracted against 43% from untreated biomass. An incubation step after PEF-treatment, further improved the yields, up to 83% of total lipids. Increasing the solvent volume by factor 2 offered no improvement. In comparison, extraction with two other systems utilizing only ethanol at room temperature or elevated at 60 °C were ineffective with less than 30% of total lipids extracted. Regarding cascade extraction, carbohydrate release after PEF was detected albeit in low concentrations. PEF-treated samples displayed slightly better kinetics during the enzymatic protein hydrolysis compared to untreated or HPH-treated biomass. The yields from a subsequent lipid extraction were not affected after PEF but were significantly increased for untreated samples (66% of total lipids), while HPH displayed the lowest yields (~ 49% of total lipids). Conclusions PEF-treatment successfully promoted lipid extraction from S. almeriensis but only in combination with a polar:neutral co-solvent (ethanol:hexane). After enzymatic protein hydrolysis in cascade processing; however, untreated biomass displayed equal lipid yields due to the disruptive effect of the proteolytic enzymes. Therefore, the positive impact of PEF in this scheme is limited on the improved reaction kinetics exhibited during the enzymatic hydrolysis step.
... Any cell wall disruption procedure, whether mechanical, chemical, or enzymatic, can enhance the extraction of intracellular compounds such as carotenoids (Michelon et al. 2012). The required volume of solvents for extracting the lipids is dependent on the solubility of the molecules as well as their capacity to penetrate the cell wall (Yao et al. 2012), hence a cell breakage method might also be advantageous for reducing the amount of solvents. ...
Article
Full-text available
Extraction of carotenoids and fatty acids from microalgae is a technological bottleneck in processing. An improved extraction process was developed to scale the production of these bioproducts from Nannochloropsis gaditana. Different cell disruption methods were evaluated in terms of carotenoid release. Ethanol was substituted with isopropyl alcohol in a three-component solution of water:isopropyl alcohol:hexane (WIH), in which the extracts were separated by solution partitioning. This resulted in higher carotenoid and fatty acid recovery yields if compared with the standard method. The extraction method was replicated on a pilot scale, obtaining similar carotenoid recovery yields, higher than those of the standard method. Although fatty acid recovery was lower than that of the small-scale tests, yields above 85% were obtained. This demonstrated that the method was scalable for the extraction of high-value products from microalgae up to 10-L reactor volume. The use of isopropyl alcohol, which is cheaper than ethanol, and the separation of the solution phases by partitioning (avoiding drying) could contribute to reduce operation costs of downstream processing.
... Each of the described stages was evaluated by comparing the number of identified lipids, as well as the chromatographic peak areas, indicating extraction recovery. The overnight extraction with isopropanol/MeOH (1:1, v/v) of the solid sample at 48°C was described in previous works as useful to enhance the lipid diffusion into the extraction solvent [29,30]. Nevertheless, the comparison of the extraction procedure with or without this step indicated a non-significant difference in the amount of extracted lipids. ...
Article
The chemical composition of Cannabis sativa L. has been extensively investigated for several years; nevertheless, a detailed lipidome characterization is completely lacking in the literature. To achieve this goal, an extraction and enrichment procedure was developed for the characterization of phospholipids and sulfolipids. Firstly, a study on the solid-liquid extraction was performed, to maximize the recovery of the considered lipids; the best procedure consisted of a simple extraction with a mixture of methanol and chloroform (1:1, v/v). The hemp extracts were analyzed by ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry and lipids were tentatively identified by Lipostar. To improve the number of identifications, an enrichment method, based on graphitized carbon black solid phase extraction, was evaluated to fractionate phospholipids and sulfolipids into separate eluates. Recovery and matrix effects of the procedure were determined on a mixture of standard lipids, containing representative compounds for each considered lipid class. The optimized method allowed the tentative identification of 189 lipids, including 51 phospholipids and 80 sulfolipids, in the first and second fractions, respectively. The detection of only 6 sulfolipids in the first fraction and 9 phospholipids in the second fraction proved the efficacy of the fractionation method, which also allowed the number of lipid identifications to be increased compared to the same procedure without enrichment, which scored 100 lipids. Finally, a semi-quantitative analysis permitted the hemp polar lipidome to be characterized. The results of this study allow knowledge of the hemp chemical composition to be improved with a detailed description of its phospho- and sulfolipid profiles. Graphical abstract.
... A polar lipid extract from green algae was prepared by a modified method. 31,32 First, 1.0 mL of Erdschreiber's medium 28 with green algae was centrifuged and frozen/thawed three times. The thawed paste was then sonicated for 10 min followed by addition of 0.4 mL of isopropanol. ...
Article
Algae lipids contain long-chain saturated and polyunsaturated fatty acids. The lipids may be transesterified to generate biodiesel fuel. Here, we compare polar lipid compositions for two microalgae, Nannochloropsis oculata and Haematococcus pluvialis, that are prospective lipid-rich feedstock candidates for an emerging biodiesel industry. Online nano liquid chromatography coupled with negative electrospray ionization 14.5 T Fourier transform ion cyclotron resonance mass spectrometry ((-)ESI FT-ICR MS) with newly modified ion optics provides ultrahigh mass accuracy and resolving power to identify hundreds of unique elemental compositions. Assignments are confirmed by isotopic fine structure for a polar lipid extract. Collision-induced-dissociation (CID) MS/MS provides additional structural information. H. pluvialis exhibits more highly polyunsaturated lipids than does N. oculata.
... The hydrophilic moieties make the polar lipid difficult to be extracted by nonpolar lipids and they can behave as emulsifiers during a wet extraction. In autotrophic microalgae species, glycolipids and phospholipids can comprise 17-90% of the total lipids (depending on strain and growth conditions) [54] (also see Table 1) and glycolipids mainly occur in chloroplasts [49]. Most carotenoids are naturally occurring in photosynthetic pigment-protein complexes, fitting into or spanning across the lipid bilayer membrane [55]. ...
Article
Full-text available
Biological lipids derived from oleaginous microorganisms are promising precursors for renewable biofuel productions. Direct lipid extraction from wet cell-biomass is favored because it eliminates the need for costly dehydration. However, the development of a practical and scalable process for extracting lipids from wet cell-biomass is far from ready to be commercialized, instead, requiring intensive research and development to understand the lipid accessibility, mechanisms in mass transfer and establish robust lipid extraction approaches that are practical for industrial applications. This paper aims to present a critical review on lipid recovery in the context of biofuel productions with special attention to cell disruption and lipid mass transfer to support extraction from wet biomass.
... Nannochloropsis is a marine microalga of great industrial interest because of its ability to accumulate large amounts of lipids and other valuable compounds, such as eicosapentaenoic acid (EPA) and carotenoids [19][20][21] . However, it shows unusual resistance to mechanical and chemical treatments, which makes the extraction of intracellular components a challenging and energy-consuming process [22,23] . The results of the present study indicate that an optimized multienzyme treatment of Nannochloropsis microalgae can lead to a significant improvement in lipid extraction. ...
Article
Cell wall disruption is one of the most critical and energy-consuming steps in the overall process of lipid extraction from microalgae. In this paper we investigate a multi-enzyme pretreatment based on the use of cellulase (CEL) and mannanase (GMA) for the recovery of lipids from the marine microalga Nannochloropsis sp. A central composite design coupled with response surface methodology was used to optimize the treatment and evaluate the effect of temperature (T = 15–75 °C), pH (2–8), pretreatment time (P = 30–270 min), CEL dosage (D1 = 0–20 mg/g) and GMA dosage (D2 = 0–2 mg/g) on lipid extraction. About 90% of lipids were recovered from Nannochloropsis cells pretreated under optimal process conditions (T = 53 °C, pH = 4.4, P = 210 min, D1 = 13.8 mg/g and D1 = 1.5 mg/g). FTIR spectra and TEM images of Nannochloropsis cells showed that the enzymatic treatment produced significant alterations in the algal cell wall structure, with extensive loss of cell boundaries and release of intracellular material. Overall, the results obtained indicate that the proposed approach can significantly improve the recovery of lipids from Nannochloropsis sp., further supporting the use of enzymes in microalgal processes.
... Attention was focused on Nannochloropsis sp., a marine microalga of great biotechnological interest for its ability to accumulate large amounts of lipids (Perin et al., 2014) and other valuable compounds, such as the omega-3 polyunsaturated fatty acid EPA and the carotenoids astaxanthin and zeaxanthin (Leu and Boussiba, 2014). Because of its rigid and highly structured cell wall (Yao et al., 2012), Nannochloropsis shows unusual resistance to degradation and therefore represents a suitable model organism for testing the efficacy of enzymatic treatments. Two commercial enzyme preparations, one rich in cellulase and the other rich in galactomannanase, were used for treating Nannochloropsis. ...
Article
Full-text available
The feasibility of using Dissolved Organic Carbon (DOC) measurements as a means to assess the efficacy of an enzyme-assisted pretreatment on the recovery of lipids from microalgae was investigated. Attention was focused on Nannochloropsis sp., a marine microalga of great biotechnological interest for its ability to accumulate large amounts of lipids and other valuable compounds. The enzymatic pretreatment was carried out using two commercial enzyme preparations, one (CEL) rich in cellulase and the other (GMA) rich in galactomannase. Experiments were performed according to a fractional two-level factorial design. The factors studied were temperature (15–75 °C), pH (2–8), pretreatment time (30– 270 min), CEL dosage (0–20 mg/g) and GMA dosage (0–2 mg/g). DOC was determined by a TOC analyzer and used as the response variable. Under the experimental design conditions, temperature, pH, pretreatment time and CEL dosage were found to be statistically significant (p < 0.05), with the former factor being the most influential. No significant interactions were observed between the main factors, indicating that each of them exerted its effect independently of the others. A good correlation was also found between the measured DOC values and the yields of lipid extraction from the enzymatically treated biomass, demonstrating that DOC measurements can be used to quantify the enzyme-induced degradation of algal cell walls.
... Lipids form an important group of macromolecules, playing vital roles in cellular organization and structure, energy resources, signal transduction, cell trafficking and sorting of other macromolecules to specic target sites. 1,2 Microalgae are able to synthesize a variety of lipids, including storage and structural lipids. These structural lipids are mainly composed of membrane phospholipids and glycolipids. ...
... 11,12 The effect of salinity on algal elemental composition (CHNS) has not been studied so far. Dineshkumar et al. 14 reported elemental compositions of Chlorella minutissima in sparged CO 2 and ue gas aerated culture. In the present investigation optimum concentration of NaCl was used to analyze the elemental composition. ...
... Yao et al. showed yellow uorescence of neutral lipid in Chlamydomonas reinhardtii. 2 Neutral lipid accumulation in the marine strains Alexandrium minutum and Heterosigma akashiwo was shown to increase by 200% and 30% respectively under N deciency and lower temperature. 49 One of the most important functions of neutral lipid (TAG) in microalgal cells is to provide energy for metabolic requirements of cell. ...
Article
Full-text available
A laboratory based integrated approach was undertaken for improvement of lipid accumulation in green microalgae under sodium chloride (NaCl) stress. The maximum biomass yields (1.22 ± 0.04 g L⁻¹ in Chlorella and 1.31 ± 0.04 g L⁻¹ in Chlorococcum) were obtained in the media with initial NaCl concentrations at 2 g L⁻¹ (for Chlorella) and 0.05 g L⁻¹ (for Chlorococcum) after 14 days of culture. Interestingly, maximum lipid accumulation obtained was 45.8 ± 0.4% w/v for Chlorella (on day eight) and 36.33 ± 0.56% w/v for Chlorococcum (on day ten) at an exposure of 5 g L⁻¹ and 1.5 g L⁻¹ NaCl concentrations, respectively. Fatty acid profiles of methyl esters for neutral and polar lipid fractions showed the presence of myristic (C14:0), palmitic (C16:0), palmitoleic (C16:1), oleic (C18:1) and linoleic (C18:2) acids as major fatty acids. Fluorescence intensities (% positive Nile red stained cells) of neutral and polar lipid fractions were also higher in NaCl stress conditions. A significant correlation between polar lipid and neutral lipid was found in both Chlorella (r² = 0.979) and Chlorococcum (r² = 0.972). Flow cytometric study demonstrated a positive fluorescence signal for neutral and polar lipid bodies related to Nile red fluorescence. Associated biochemical changes, like those in total chlorophyll, carotenoid, carbohydrate and protein contents, were determined under variable NaCl concentrations. The elemental compositions (CHNS) and CO2 fixation rate were assessed using high lipid yielding cells under optimum NaCl concentrations. Biodiesel fuel properties were obtained from high lipid yielding cells of the test microalgae and compared with Indian and international diesel standards. Finally large-scale cultivation of Chlorella ellipsoidea was performed in a hybrid photobioreactor (800 L capacity) and the highest biomass and lipid content obtained was 1.66 ± 0.09 g L⁻¹ (at 8 days) and 54.73 ± 1.78% w/v (at 10 days) at 5 g L⁻¹ NaCl respectively. This optimized NaCl concentration makes it an economical substitute for biodiesel production on a large scale.