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1.
Chemosphere ; 242: 125079, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31678847

RESUMO

Depletion of fossil fuel sources and their emissions have triggered a vigorous research in finding alternative and renewable energy sources. In this regard, algae are being exploited as a third generation feedstock for the production of biofuels such as bioethanol, biodiesel, biogas, and biohydrogen. However, algal based biofuel does not reach successful peak due to the higher cost issues in cultivation, harvesting and extraction steps. Therefore, this review presents an extensive detail of deriving biofuels from algal biomass starting from various algae cultivation systems like raceway pond and photobioreactors and its bottlenecks. Evolution of biofuel feedstocks from edible oils to algae have been addressed in the initial section of the manuscript to provide insights on the different generation of biofuel. Different configuration of photobioreactor systems used to reduce contamination risk and improve biomass productivity were extensively discussed. Photobioreactor performance greatly relies on the conditions under which it is operated. Hence, the importance of such conditions alike temperature, light intensity, inoculum size, CO2, nutrient concentration, and mixing in bioreactor performance have been described. As the lipid is the main component in biodiesel production, several pretreatment methods such as physical, chemical and biological for disrupting cell membrane to extract lipid were comprehensively reviewed and presented. This review article had put forth the recent advancement in the pretreatment methods like hydrothermal processing of algal biomasses using acid or alkali. Eventually, challenges and future dimensions in algal cultivation and pretreatment process were discussed in detail for making an economically viable algal biofuel.


Assuntos
Biocombustíveis/provisão & distribução , Biomassa , Fotobiorreatores/normas , Luz , Lipídeos/química , Lipídeos/isolamento & purificação , Microalgas/metabolismo , Fotobiorreatores/tendências
2.
Anal Bioanal Chem ; 412(2): 449-462, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31797019

RESUMO

In the last decades, microbial oils have been extensively investigated as a renewable platform for biofuel and oleochemical production. Offering a potent alternative to plant-based oils, oleaginous microorganisms have been the target of ongoing metabolic engineering aimed at increasing growth and lipid yields, in addition to specialty fatty acids. Discovery proteomics is an attractive tool for elucidating lipogenesis and identifying metabolic bottlenecks, feedback regulation, and competing biosynthetic pathways. One prominent microbial oil producer is Cutaneotrichosporon oleaginosus, due to its broad feedstock catabolism and high lipid yield. However, this yeast has a recalcitrant cell wall and high cell lipid content, which complicates efficient and unbiased protein extraction for downstream proteomic analysis. Optimization efforts of protein sample preparation from C. oleaginosus in the present study encompasses the comparison of 8 lysis methods, 13 extraction buffers, and 17 purification methods with respect to protein abundance, proteome coverage, applicability, and physiochemical properties (pI, MW, hydrophobicity in addition to COG, and GO analysis). The optimized protocol presented in this work entails a one-step extraction method utilizing an optimal lysis method (liquid homogenization), which is augmented with a superior extraction buffer (50 mM Tris, 8/2 M Urea/Thiourea, and 1% C7BzO), followed by either of 2 advantageous purification methods (hexane/ethanol or TCA/acetone), depending on subsequent applications and target studies. This work presents a significant step forward towards implementation of efficient C. oleaginosus proteome mining for the identification of potential targets for genetic optimization of this yeast to improve lipogenesis and production of specialty lipids. Graphical abstract.


Assuntos
Basidiomycota/metabolismo , Proteínas Fúngicas/metabolismo , Proteômica , Proteínas Fúngicas/isolamento & purificação , Lipídeos/isolamento & purificação , Proteólise , Solubilidade
3.
Food Chem ; 309: 125732, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31706676

RESUMO

Impacts of different pretreatment conditions and atmosphere on yield and oxidative stability of lipids from Pacific white shrimp (Litopenaeus vannamei) cephalothorax using ultrasonic assisted extraction (UAE) process were studied. Cephalothorax was subjected to vacuum-microwave (VM) heating prior to UAE using a mixture of isopropanol/n-hexane (1:1) as solvent. Nitrogen gas was flushed at two flow rates; low (2.15 l/min) and high (4.35 l/min) into the system during ultrasonication. Vacuum-microwave heating resulted in the increase of lipid yield and highest yield was observed in the samples extracted by a combination of VM and UAE. Tannic acid (TA) was incorporated into cephalothorax at three different levels (0.05, 0.1 and 0.2%) in combination with VM, followed by nitrogen flushing. Nitrogen flushing during ultrasonication process resulted in the increased oxidative stability of lipids as confirmed by low PV, TBARS and FFA. Furthermore, astaxanthin content in the lipid was found to be increased by aforementioned treatments.


Assuntos
Lipídeos/química , Penaeidae/metabolismo , Sonicação , 2-Propanol/química , Animais , Atmosfera , Ácidos Graxos/análise , Hexanos/química , Lipídeos/isolamento & purificação , Micro-Ondas , Oxirredução , Solventes/química , Taninos/química , Vácuo , Xantofilas/análise
4.
J Food Sci ; 84(12): 3594-3600, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31762029

RESUMO

The effects of four different extraction methods (Folch, Soxhlet, two-step, and enzyme-assisted aqueous extraction) on the yields, lipid class, fatty acids (FAs) composition, minor components (including carotenoid, cholesterol), and thiobarbituric acid reactive substances values of lipids in the hepatopancreas of Chinese mitten crab (Eriocheir sinensis) were investigated. The C16:0, C18:1, and C18:2 were identified to be the dominant FAs in crab lipids, and the FAs were present in the form of triglycerides. The Soxhlet and enzyme-assisted extraction were more suitable for crab lipids extraction, showing higher extraction rates and oxidative stability. Especially, the lipid extracted by enzyme-assisted extraction has high carotenoids content. The components of crab lipids extracted by enzyme-assisted aqueous extraction were further identified using untargeted metabolomics methods. The polyunsaturated fatty acid, sterols, amino acids, products of lipid ß-oxidation and ATP degradation, phosphatidyl ethanolamine, and astaxanthin were founded in crab oil. PRACTICAL APPLICATION: The Chinese mitten crab (Eriocheir sinensis) is a popular aquatic food in China. The hepatopancreas is the major lipid storage organ of crab, and the distinctive flavor of crab is mainly from it. To compare the different extraction methods on yield, composition and properties of crab lipids can be helpful for lipids production from crab hepatopancreas. Meanwhile, the crab hepatopancreas lipids are rich in polyunsaturated fatty acids and astaxanthin, and have potential to be as a functional component and a crab flavor additive in food industry.


Assuntos
Métodos Analíticos de Preparação de Amostras/métodos , Braquiúros/química , Hepatopâncreas/química , Lipídeos/isolamento & purificação , Animais , China , Ácidos Graxos/química , Ácidos Graxos/isolamento & purificação , Aromatizantes/química , Aromatizantes/isolamento & purificação , Lipídeos/química
5.
Molecules ; 24(18)2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31510066

RESUMO

This study evaluated the effect of seasonal variation on the physicochemical, biochemical, and nutritional composition of Gracilaria manilaensis. Sampling was designed during the main monsoon seasons in Malaysia-the Southwest monsoon (SWM) and Northeast monsoon (NEM)-to understand the intraspecific variation (p < 0.05). Carbohydrates, protein, and dietary fiber were found to be higher in NEM-G. manilaensis, whereas a higher ash content was quantified in SWM-G. manilaensis. No significant differences were found in crude lipid and moisture content (p > 0.05). Vitamin B2 was calculated as (0.29 ± 0.06 mg 100 g-1) and (0.38 ± 0.06 mg 100 g-1) for the NEM and SWM samples, respectively (p < 0.05). The fatty acid profile showed the dominance of saturated fatty acids (SFAs)-palmitic acids, stearic acid, and myristic acid-while the mineral contents were found to be good sources of calcium (1750.97-4047.74 mg 100 g-1) and iron (1512.55-1346.05 mg 100 g-1). Tryptophan and lysine were recorded as the limiting essential amino acids (EAAs) in NEM G. manilaensis, while leucine and phenylalanine were found to be the limiting EAAs in the SWM samples. None of the extracts exhibited antibacterial properties against the screened strains. The study concluded that seasonal changes have a great effect on the biochemical composition of G. manilaensis.


Assuntos
Carboidratos/química , Ácidos Graxos/química , Gracilaria/química , Valor Nutritivo , Carboidratos/isolamento & purificação , Fibras na Dieta/análise , Ácidos Graxos/isolamento & purificação , Lipídeos/química , Lipídeos/isolamento & purificação , Malásia , Minerais/química , Minerais/isolamento & purificação , Extratos Vegetais/química , Proteínas/química , Proteínas/isolamento & purificação , Estações do Ano
6.
Bioresour Technol ; 291: 121819, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31369925

RESUMO

In this study, experiments on pretreating one species of microalgae (Chlorella pyrenoidosa) using one kind of ionic liquid (IL) of [BMIM]Cl were conducted. The aim of this work is to evaluate the recycling efficacy of expensive IL solvent for effective cell disruption. It was indicated that the molecular structure of IL was stable during the recycling test. Five times antisolvent precipitation of microalgae debris after lipid extraction using methanol recovered 99.8% IL with the energy consumption of 4.46 MJ per kg dry Chlorella pyrenoidosa. The chromatography was used to separate IL and hydrolysates, resulting in the IL loss below 1.97 g per kg dry Chlorella pyrenoidosa.


Assuntos
Chlorella/química , Imidazóis/química , Lipídeos/isolamento & purificação , Microalgas/química , Esgotos
7.
Bioresour Technol ; 291: 121834, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31371157

RESUMO

In present study, lipids were extracted from unbroken microalga Chlorella vulgaris with high water content (50% microalgal solution) through three-phase partitioning (TPP). The method was found to extract around 15.9% of total lipid transformable to methyl esters (LTMEs) from unbroken microalgal cells which is two times of Bligh and Dyer method. We investigated the effects of various parameters on TPP performance and were optimised through response surface methodology. The results indicated that incubation duration, temperature and extraction time were positively correlated with LTME extraction efficiency. The optimum temperature was 60 °C, incubation duration was 120 min, extraction time was 60 min, ratio of solvent to DKP was 1:1. The FAME yield was calculated as 12.05% and major fatty acids together accounted for 71.33% which indicated the great potential of the proposed lipid extraction procedure for microalga-based biodiesel production.


Assuntos
Biocombustíveis , Biomassa , Chlorella vulgaris/metabolismo , Lipídeos/isolamento & purificação , Microalgas/metabolismo , Ácidos Graxos/metabolismo , Lipídeos/biossíntese , Solventes , Temperatura Ambiente , Água
8.
Mar Drugs ; 17(8)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31374944

RESUMO

Microalgae are considered as excellent candidates for bioactive compounds, yet microalgal residues remaining after the extraction of one or two compounds are usually discarded, which is not economical. This study demonstrates the alkaline extraction of proteins from Chlorella pyrenoidosa residue after lipid and pigment extractions, and their functional properties. Single-factor experiments and response surface methodology were used to obtain the optimal conditions for protein extraction. Based on our results, a maximum protein yield of 722.70 mg/g, was obtained under the following extraction conditions: sodium hydroxide concentration 7.90%, extraction temperature 70.00 °C, extraction time 34.80 min, and microalgal residue concentration 8.20 mg/mL. The molecular weight of microalgal residue protein isolate (MRPI) was mainly distributed at the regions of 0.18-0.50 kDa, 0.50-1.50 kDa, and 1.50-5.00 kDa. The essential amino acid content was greater than the values recommended by FAO/WHO standards; a high essential amino acid index value (1.49) was another good indication that MRPI is suitable for human consumption. Moreover, MRPI exhibited excellent emulsifying properties and antioxidant activity, which suggests it may be useful as an emulsifying agent and antioxidant. These findings could improve the extraction methods of functional protein from microalgal residue and add value to microalgae-based bioactive compound production processes.


Assuntos
Chlorella/química , Microalgas/química , Extratos Vegetais/farmacologia , Proteínas de Plantas/farmacologia , Sequência de Aminoácidos , Aminoácidos Essenciais/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Emulsificantes/química , Emulsificantes/isolamento & purificação , Emulsificantes/farmacologia , Alimento Funcional , Lipídeos/isolamento & purificação , Peso Molecular , Estresse Oxidativo/efeitos dos fármacos , Pigmentos Biológicos/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Hidróxido de Sódio/química , Temperatura Ambiente
9.
Talanta ; 205: 120162, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31450465

RESUMO

Microalgae have recently become a popular functional food due to their health benefits. Sulfolipids, a class of substances abundant in this matrix, have been reported to have interesting bioactivities, such as anti-carcinogenic activity. However, despite the potential interest in sulfolipids, a dedicated analytical method for their characterization is currently lacking but would significantly increase the coverage of sulfolipids with respect to the direct lipidomic analysis. To achieve this goal, in this work a procedure, based on graphitized carbon black solid phase extraction, was developed for clean-up and enrichment of sulfolipids (sulfoquinovosyldiacylglycerols and sulfoquinovosylmonoacylglycerols) and it was applied to spirulina (Arthrospira platensis) microalgae. A careful study of the solid phase extraction conditions was performed, first to maximize the recovery of reference standards, then to increase the total number of identified sulfolipids from the spirulina lipid extract. All samples were analysed by ultra-high performance liquid chromatography coupled to high resolution mass spectrometry and lipids were tentatively identified by Lipostar, for a reliable lipid structure assignment. The developed method was compared to the direct lipidomic analysis without enrichment, to establish the enrichment efficiency in terms of number of identifications. From the comparison, the enrichment procedure proved better and allowed the tentative identification of 199 sulfolipids, which is the largest number reported so far for the Arthrospira platensis species. The described method was validated in terms of precision, accuracy, recovery, limit of quantitation and detection for two sulfolipids. Finally, a relative lipid quantitation based on peak area was carried out on the microalgae sample, which indicated nine abundant sulfolipids as representing ca. 60% of sulfolipids in spirulina microalgae.


Assuntos
Cromatografia Líquida/métodos , Grafite/química , Lipídeos/análise , Lipídeos/química , Espectrometria de Massas/métodos , Microalgas/química , Fuligem/química , Lipídeos/isolamento & purificação , Extração em Fase Sólida , Spirulina/química
10.
Methods Mol Biol ; 1995: 51-89, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31148121

RESUMO

There is an increasing need for the development of alternative energy sources with a focus on reducing greenhouse gas emissions and striving toward a sustainable economy. Bioethanol and biodiesel are currently the primary choices of alternative transportation fuels. At present, biodiesel is not competitive with conventional fuel due to its high price, and the only way to compete with conventional fuel is to improve the quality, reduce the costs, and coproduce value-added products. With the high demand for lipids in the energy sector and other industrial applications, microbial lipids accumulated from microorganisms, especially oleaginous fungi and yeasts have been the important topic of many recent research studies. This chapter summarizes the current status of knowledge and technology about lipid production by oleaginous fungi and yeasts for biofuel applications and other value-added products. The chapter focuses on several aspects such as the most promising oleaginous strains, strain development, improvement of lipid production, methods and protocols to cultivate oleaginous fungi, substrate utilization, fermentation process design, and downstream processing. The feasibility and challenges during the large-scale commercial production of microbial lipids as fuel sources are also discussed. It provides an overview of microbial lipid production biorefinery and also future development directions.


Assuntos
Biocombustíveis , Fungos/metabolismo , Microbiologia Industrial/métodos , Metabolismo dos Lipídeos , Biocombustíveis/análise , Biocombustíveis/microbiologia , Fermentação , Fungos/química , Fungos/crescimento & desenvolvimento , Lipídeos/análise , Lipídeos/isolamento & purificação
11.
Methods Mol Biol ; 1995: 91-101, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31148122

RESUMO

An ever increasing energy demand and fast depletion of fossil fuels have led to increased consideration of bacterial lipids as a renewable biofuel source. Many methods are available for both physical and chemical extraction of bacterial lipids. The method of choice will depend on the nature of sample to be analyzed, combinations of solvent systems preferred, content and quality of the lipid to be analyzed, types of equipment available, and time of the extraction procedures employed. Here we describe the most reliable, routine method of extracting bacterial lipids and evaluating the growth kinetic parameters like biomass and lipid productivity and lipid content. We also describe the method of comparing bacterial fatty acid methyl ester peaks with standard peaks for analysis.


Assuntos
Bactérias/metabolismo , Lipídeos/análise , Lipogênese , Bactérias/química , Bactérias/crescimento & desenvolvimento , Biocombustíveis/análise , Biomassa , Cromatografia Gasosa/métodos , Cianobactérias/química , Cianobactérias/crescimento & desenvolvimento , Cianobactérias/metabolismo , Esterificação , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Lipídeos/isolamento & purificação
12.
Methods Mol Biol ; 1995: 131-140, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31148125

RESUMO

Although most algal biofuel research has focused on microalgae, macroalgae are also potential sources of lipid for the production of biodiesel and other liquid fuels. Reliable, accurate methods for assessing the lipid composition of biomass are essential for the development of macroalgae in this area. The conventional methods most commonly used to evaluate lipid composition, such as those of Bligh and Dyer and Folch, do not provide complete extraction of lipids in photosynthetic cells/tissues and therefore do not provide an accurate accounting of lipid production. Here we present a 2-EE lipid extraction protocol, a method which has been demonstrated to be superior to conventional lipid extraction methods for microalgae, adapted for use with macroalgae.


Assuntos
Lipídeos/análise , Alga Marinha/química , Fracionamento Químico/métodos , Cromatografia em Camada Delgada/métodos , Etilenoglicóis/química , Lipídeos/isolamento & purificação
13.
Methods Mol Biol ; 1995: 151-159, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31148127

RESUMO

Lipids accumulated inside microbial cells (such as fungi, bacteria, yeast, microalgae, and macroalgae) have to be extracted for production of biodiesel and/or oleochemicals via thermochemical or thermocatalytic processes. Extraction methods for separation as well as quantification of lipids from microbes require organic solvents (such as hexane, methanol, and tetrahydrofuran) and involve multiple unit operations/steps such as thermal treatment (supercritical CO2 extraction), chemical treatment (acid or base, enzymes), mechanical operations (such as sonication and ball beating), liquid-solid separation, liquid-liquid extraction, and gravimetric or chromatographic analysis.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Lipídeos/isolamento & purificação , Extração Líquido-Líquido/métodos , Bactérias/química , Cromatografia Gasosa/métodos , Fungos/química , Hidrólise , Microalgas/química , Alga Marinha/química , Sonicação/métodos , Leveduras/química
14.
Methods Mol Biol ; 1995: 395-403, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31148141

RESUMO

Over the last decade, finding bacterial strains with ability to accumulate high concentrations of lipids has gained increasing interest, since these lipids may be used in different industries. Here we describe two methods for evaluation of lipid accumulation in cyanobacteria, following by our personal reflection on issues surrounding the use of these methods. First, we present the Bligh and Dyer protocol as a traditional extraction method using organic solvents for quantitative determination of lipids and next Nile red, a selective fluorescent stain, that has been used as a rapid approach for both qualitative and quantitative measurement of lipids.


Assuntos
Cianobactérias/metabolismo , Metabolismo dos Lipídeos , Lipídeos/análise , Cianobactérias/química , Corantes Fluorescentes/análise , Lipídeos/isolamento & purificação , Oxazinas/análise , Espectrometria de Fluorescência/métodos , Coloração e Rotulagem/métodos
15.
J Chromatogr A ; 1601: 145-154, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31072602

RESUMO

RNA interference offers a novel approach for the development of new therapeutics for targets that are otherwise "undruggable" using traditional modalities. The safety and efficacy of siRNA-based therapy mainly rely on lipid or polymer-based nanocarriers to overcome inherent barriers to a systemic delivery of siRNA. A multicomponent lipid nanoparticle (LNP) system is a promising delivery platform, typically consisting of a cationic lipid, phospholipid, PEG-containing short-chain lipid, and cholesterol. Characterization and chemical analysis of the LNP formulation is important to assure drug product stability, a key consideration for chemistry, manufacturing and control strategy. Here we report an ion-pair reversed phase UHPLC method capable of simultaneously separating both siRNA and functional lipids in LNPs with a minimal retention gap for two classes of biologically essential yet chemically distinct molecules. Key chromatographic parameters critical to the separation are discussed, including the structure of the ion-pair agent, stationary phase chemistry, column temperature and an organic additive. The results showed that the retention time of siRNA is tunable by using various ion-pair reagents. The retention factor of the siRNA exhibited a first order relationship with the number of carbons in the alkyl chain of the ion-pair reagents. In contrast, the type of ion-pair reagent has no significant impact on the separation of phospholipids. Separations using a BEH phenyl column and dibutylammonium acetate as the ion-pair reagent showed satisfactory selectivity for a range of double-stranded siRNAs and phospholipids, key components for lipid nanoparticle formulations. Furthermore, the method was applied to the separation of an experimental LNP formulation, demonstrating good selectivity for siRNA, functional lipids and their potential degradation products.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia de Fase Reversa , Lipídeos/isolamento & purificação , Nanopartículas/química , RNA Interferente Pequeno/isolamento & purificação , Estabilidade de Medicamentos , Interferência de RNA
16.
J Assist Reprod Genet ; 36(7): 1379-1385, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31073727

RESUMO

PURPOSE: To determine if levels of very long chain polyunsaturated fatty acids (VLC-PUFA; ≥ 28 carbons;4-6 double bonds) in human sperm correlate with sperm quantity and quality as determined by a complete semen analysis. METHODS: Ejaculates from 70 men underwent a complete semen analysis, which included volume, count, motility, progression, agglutination, viscosity, morphology, and pH. For lipid analysis, sperm were pelleted to remove the semen. Lipids were extracted from the cell pellet and methyl esters of total lipids analyzed by gas chromatography. The sphingolipids were enriched and sphingomyelin (SM) species measured using tandem mass spectrometry. Pair-wise Pearson correlation and linear regression analysis compared percent VLC-PUFA-SM and percent docosahexaenoic acid (DHA) to results from the semen analysis. RESULTS: VLC-PUFA-SM species having 28-34 carbon fatty acids were detected in sperm samples, with 28 and 30 carbon VLC-PUFA as most the abundant. The sum of all VLC-PUFA-SM species comprised 0 to 6.1% of the overall SM pool (mean 2.1%). Pair-wise Pearson analyses showed that lower levels of VLC-PUFA-SM positively correlated with lower total motile count (0.68) and lower total count (0.67). Total VLC-PUFA-SM and mole % DHA (22:6n3) were not strongly correlated (- 0.24). Linear regression analysis confirmed these findings. CONCLUSION: This study revealed a positive correlation between the levels of VLC-PUFA with sperm count and total motile count and suggests that both sperm quality and quantity may depend on the presence of VLC-PUFA. The lack of correlation between VLC-PUFA and DHA suggests that low VLC-PUFA levels do not result from inadequate PUFA precursors.


Assuntos
Ácidos Graxos Insaturados/metabolismo , Sêmen/metabolismo , Espermatozoides/metabolismo , Esfingomielinas/metabolismo , Adolescente , Adulto , Ácidos Graxos Insaturados/genética , Fertilidade/genética , Humanos , Lipídeos/química , Lipídeos/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Análise do Sêmen , Contagem de Espermatozoides , Motilidade Espermática/genética , Espermatozoides/patologia , Esfingomielinas/genética , Espectrometria de Massas em Tandem , Adulto Jovem
17.
Anal Bioanal Chem ; 411(16): 3685-3693, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31053955

RESUMO

An ultrahigh-pressure supercritical fluid extraction method was optimized and applied to extract seed oil lipids from two moringa species, namely Moringa oleifera (MO) and Moringa peregrina (MP). A full-factorial design was used to investigate the direct and interaction influence of pressure and temperature in the range of 40 to 80 MPa and 40 to 70 °C, respectively, on the extracted amount of oil from crushed seeds. The results revealed that pressure has a significant positive influence on the extracted amount of oil. The best extraction condition using neat CO2 was found at 80 MPa and 57 °C, yielding 396 ± 23 and 529 ± 26 mg oil per gram of seeds for MO and MP, respectively. An extraction kinetics study revealed a mainly solubility-controlled extraction of oil, and 28 g of CO2 was required to extract 400 mg of oil per gram of seeds of MO using the developed method. Addition of ethanol to the sample prior to the extraction increased the proportion of extractable polar lipids as well as the total amount of extracted oil. The developed method increased the extracted amount of oil twofold compared to a reference method based on solvent sonication. The obtained oil consisted mainly of glycerolipids, sterol esters, and phospholipids. Phospholipids, campesterol, and stigmasterol ester concentrations were found to be higher in MO while cholesterol ester was more abundant in MP.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Lipídeos/isolamento & purificação , Moringa/embriologia , Sementes/química , Temperatura Alta , Espectrometria de Massas/métodos , Moringa/classificação , Óleos Vegetais/química , Óleos Vegetais/isolamento & purificação , Pressão , Sonicação , Especificidade da Espécie
18.
Lipids ; 54(5): 347-356, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31087412

RESUMO

Total lipids were extracted from razor clams Sinonovacula constricta and Solen gouldi, and the molecular species of glycerophospholipid (Gpl) including choline glycerophospholipid (ChoGpl), ethanolamine glycerophospholipid (EtnGpl), serine glycerophospholipid (SerGpl), inositol glycerophospholipid (InsGpl), lysoChoGpl, lysoEtnGpl, and lysoSerGpl were characterized using a direct-infusion tandem mass spectrometric method for the first time. Meanwhile, the lipid class composition and phospholipid (PL) class composition as well as the fatty acid (FA) composition of total lipids, triacylglycerol (TAG), and PL were also investigated. About 238 and 235 molecular species were characterized, respectively, in Sinonovacula constricta and Solen gouldi. The majority of the dominant Gpl molecular species contained n-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA), especially docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Also, razor clam lipids contained a high-proportioned PL (52.19-65.41% of total lipids) and PUFA (47.94-54.81 mol%). Furthermore, PL contained a higher proportion of PUFA (63.05-67.13 mol%), especially DHA (20.04-22.47 mol%) and EPA (16.27-21.46 mol%) than TAG (the corresponding values being 33.73-34.45, 11.95-12.27, and 8.13-0.8.99 mol%, respectively). Meanwhile, phosphatidylcholine (44.38-46.21 mol%) and phosphatidylethanolamine (38.84-39.95 mol%) were dominant among PL. In consideration of the high proportion of PUFA-enriched Gpl, razor clam plays a great role in promoting human health.


Assuntos
Bivalves/química , Lipídeos/química , Lipídeos/isolamento & purificação , Animais , Bivalves/classificação , Especificidade da Espécie
19.
Bioprocess Biosyst Eng ; 42(9): 1447-1455, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31076866

RESUMO

While lipid extraction from wet microalgae has attracted attention as an economical method for microalgal biofuel production, few studies have focused the actual separation of extract phase from the emulsified extraction mixture. Here, a novel approach which utilizes hydrophobic/oleophilic filter was developed for the efficient solvent recovery. The filter was surface-modified by coating a functional polymer via initiated vapor deposition for the selective solvent permeability. While acid-treated Chlorella sorokiniana HS1 and n-hexane was stirred for lipid extraction, tubular filter module was immersed into the mixture for separation. The mixture was kept stirred during the separation to inhibit the buildup of cell debris on the filter by inducing crossflow on the filter. Extract phase was separated directly from the raffinate phase with high separation efficiency (> 98.3%) while maintaining permeation flux. The place-, space- and energy-efficient strategy reported here could be a useful tool for the solvent extraction process.


Assuntos
Chlorella/química , Filtração/instrumentação , Lipídeos/isolamento & purificação , Extração Líquido-Líquido , Microalgas/química , Interações Hidrofóbicas e Hidrofílicas , Lipídeos/química , Solventes/química
20.
Phytochemistry ; 164: 243-251, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31128818

RESUMO

Lipid-like compounds containing a dimethylarsinoyl group, i.e. Me2As(O)-, have been identified by liquid chromatography/inductively coupled plasma mass spectrometry (LC/ICP-MS) and non-aqueous reversed-phase high-performance liquid chromatography (positive and/or negative high-resolution tandem electrospray ionization mass spectrometry (NARP-HPLC/HR-ESI+(-)-MS/MS) from three strains of green algae of the genus Coccomyxa (Trebouxiophyceae, Chlorophyta). The algae were cultivated in a medium containing 10 g arsenic/L, i.e. 133.5 mmol/L of Na2HAsO4.7H2O. After extraction by methyl-tert-butyl ether (MTBE), total lipids were analyzed by ICP-MS or ESI-MS without any further separation or fractionation. A total of 39 molecular species of arsenic triacylglycerols (AsTAG), 15 arsenic phosphatidylcholines (AsPC), 8 arsenic phosphatidylethanolamines (AsPE), 6 arsenic phosphatidylinositols (AsPI), 2 arsenic phosphatidylglycerols (AsPG) and 5 unknown lipids (probably ceramides) were identified. The structures of all molecular species were confirmed by tandem MS. Dry matter of the individual strains contained different amounts of total arsenolipids, i.e. C. elongata CCALA 427 (0.32 mg/g), C. onubensis (1.48 mg/g), C. elongata S3 (2.13 mg/g). On the other hand, there were only slight differences between strains in the relative abundances of individual molecular species. Possible biosynthesis of long-chain lipids with the end group Me2As(O) has also been suggested.


Assuntos
Arsenicais/isolamento & purificação , Chlorella/química , Lipídeos/isolamento & purificação , Arsenicais/química , Arsenicais/metabolismo , Chlorella/metabolismo , Lipídeos/química , Estrutura Molecular
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