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Daryush Arabian 《Journal of the American Oil Chemists' Society》2022,99(7):569-583
Over the past few decades, microalgae have emerged as a promising option for making lipid-based bioactive compounds. The purpose of this study was to extract lipids from Chlorella vulgaris. In this study, different cell wall disruption methods such as microwave, liquid nitrogen, ultrasound (US), and bead mill were compared. We selected and optimized two systems based on their efficacy in disrupting cell walls—US and beads mill. Based on the dry weight of C. vulgaris biomass, the maximum lipid extraction by the US was 17.1% and by bead mill was 15.2%. Following cell wall disruption of C. vulgaris, chloroform–methanol (2:1) solvent combination achieved high lipid extraction. However, the hexane–ethanol (1:1) solvent combination was chosen because of its lower toxicity. Specifically, the effect of the solvent-to-biomass ratio, the temperature, and the extraction time was investigated. The results indicated that the chloroform–methanol solvent combination yielded optimal results at 8 ml/g solvents to biomass, 45°C, and 60 min and that the hexane–ethanol combination yielded optimal results at 6 ml/g, 35°C, and 73 min, respectively. The highest amount of lipids was obtained from C. vulgaris with 87.6% moisture content. As a cell wall disruption method, the US obtained 20.4% and 16.4% with a combination of chloroform–methanol solvents and hexane–ethanol, respectively. Additionally, bead milling resulted in the highest extraction yield of 17.6% for chloroform–methanol and 13.9% for hexane–ethanol. Based on the results of cell wall disruption, the US method is the most efficient cell wall disruption method in terms of lipid extraction efficiency. 相似文献
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Fahimeh Sadat Mohammadi Daryush Arabian 《Journal of the American Oil Chemists' Society》2023,100(1):45-56
The aim of this study was to determine and optimize culture media for Chlorella vulgaris microalgae under mixotrophic conditions using waste molasses as a cheap carbon source containing both organic carbons and other nutrients. In the current study, at first the growth and lipid productivity of C. vulgaris were assessed in different culture media and the best media was selected for mixotrophic growth conditions. Significant medium ingredients were screened through Plackett–Burman design. Then ingredients with positive effect were considered as a mixture component and their combinations were evaluated on lipid productivity using mixture design. According to results, Zarrouk medium was considered as the base medium with the highest biomass and lipid productivity of 72 and 7.1 mg L−1 d−1, respectively. Based on the Plackett–Burman design, out of 11 factors, molasses, NaNO3 and K2HPO4 demonstrated key roles in biomass and lipid productivity in mixotrophic conditions. Consequently, the selected three factors were investigated by mixture design. The results showed that high concentration of molasses causes decrease in biomass and lipid productivity due to high turbidity and a blend consisting of approximately 9.5 g L−1 molasses, 5 g L−1 NaNO3 and 0.15 g L−1 K2HPO4 was found as the optimum mixture with obtained lipid productivity of 115 mg L−1 d−1. In conclusion, waste molasses can be used as a promising feedstock for cost effective cultivation of C. vulgaris. 相似文献
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以海水冲厕污水作为培养液培养小球藻(Chlorella vulgaris),研究了小球藻的生长及其对海水冲厕污水中氮、磷和有机物的净化作用,并对小球藻细胞总脂含量和脂肪酸组成进行了分析。结果表明:小球藻在以海水冲厕污水作为培养液时,其生长速率和生物量与在BG11培养液中生长时相比明显较低;小球藻能够有效吸收海水冲厕污水中的氮、磷,12d时对氨氮和总磷的去除率分别达到87.9%和98.2%;采用海水冲厕污水培养出的小球藻细胞总脂含量达到33.03%,其脂肪酸组成与采用BG11培养的相比略有变化,总体以C16和C18为主,符合作为生物柴油生产原料的要求。 相似文献
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以BG11(+N)培养基和模拟生活污水为底物,考察了污水处理小球藻(Chlorella vulgaris)的自絮凝特性,探究了自絮凝机理。结果表明:以短沉淀时间运行,小球藻在模拟生活污水中自然形成絮体,沉降性良好;藻细胞表面粗糙,含有丝状、胶状胞外聚合物;絮体内部含有大量短杆菌、球菌;絮体具有相对较高的Na、P、Fe、Ca、Mg元素含量,无机物中主要物质形态为Ca4O(PO4)2。污水处理小球藻的絮凝机理为:基质条件及反应器运行参数等促使藻细胞生理过程发生改变,藻细胞分泌更多絮凝性胞外聚合物增强黏附,生化过程富集P、Fe、Ca、Mg元素改善沉降性,絮凝性细菌大量繁殖促进菌藻共絮凝。 相似文献
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Kiwa Kitada Siti Machmudah Mitsuru Sasaki Motonobu Goto Yuya Nakashima Shoichiro Kumamoto Takashi Hasegawa 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(5):657-661
BACKGROUND: Chlorella vulgaris is a green microalgae that contains various pigment components of carotenoids and chlorophylls. Supercritical CO2 is widely used for extraction of pharmaceutical compounds because it is non‐oxic and easily separated from extracted material by simply depressurizing. In this work, pharmaceutical compounds from Chlorella vulgaris have been extracted using supercritical CO2 with or without entrainer at various extraction conditions. RESULTS: Based on high performance liquid chromatography (HPLC) analysis, the extracts contained pigment components, such as lutein, β‐carotene, chlorophyll a and b. Higher extraction pressure and temperature promoted higher lutein extraction by supercritical CO2. The optimum pressure and temperature for extraction were obtained as 50 MPa and 80 °C. Ethanol as an entrainer was more effective than acetone for the extraction of pigment components. Pigment components in the extract obtained by supercritical CO2 with and without entrainer were compared with the extract obtained by a conventional extraction method. CONCLUSION: Supercritical CO2 has been successfully applied for the extraction of pigment components from Chlorella vulgaris. Supercritical CO2 enabled high selectivity for lutein extraction; however, the lutein yield was lower than that obtained by extraction using supercritical CO2 with ethanol and soxhlet. Copyright © 2008 Society of Chemical Industry 相似文献
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细胞高密度培养有利于降低微藻规模化培养成本及其生物柴油制造的成本,曝气是影响微藻规模化高密度培养的重要因素之一。以普通小球藻(Chlorella vulgaris,FACHB-1227)为研究对象,采用BG11培养基,于新型套管式沿程曝气光生物反应系统中,以细胞密度为检测指标,实验研究了曝气间隔时间对藻液中细胞密度、藻液pH值、溶氧量变化的影响。控制每次曝气时气体流量为10L/min、持续时间为0.5h,培养周期为15天。结果表明,藻液中积累的溶解氧能够及时排除,进入生物质积累稳定期时,藻液的pH值基本恒定;微藻生长稳定期时(培养12天),曝气间隔0.5h时细胞密度为7.22×106个/mL,相比于1h、1.5h、2h分别提高了9.56%、41.02%和122.1%。可见,适当减少曝气间隔时间,可显著提高藻细胞密度。 相似文献
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采用单因素实验和均匀实验获得了适合于普通小球藻异养-光自养串联培养的培养基(HA-SK培养基),其关键是C/N比和保证足够的C, N供应. 采用该培养基在摇瓶中异养-光自养串联培养普通小球藻,异养培养结束时细胞密度达13.17 g/L,经过36 h光自养培养后藻体蛋白质和叶绿素含量分别达49.75%和30.17 mg/g. 用5 L生物反应器和1 L平板光生物反应器串联培养,藻细胞密度最高可达15.36 g/L,藻体蛋白质和叶绿素含量分别达54.78%和31.23 mg/g. 表明采用HA-SK培养基进行异养-光自养串联培养可实现普通小球藻的高密度高品质培养. 相似文献
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胡长诚 《化学推进剂与高分子材料》2008,6(2):1-4
简要介绍了国外主要过氧化氢生产公司多年来过氧化氢业务发展历程,这些公司包括日本几家公司(MGC,Asahi Denka,日本过氧化物)、德国Degussa、美国FMC、法国Arkema、比利时Solvay Interox、荷兰Akzo Nobel、芬兰Kemira和韩国几家公司(东洋制铁化学等)。 相似文献
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双氧水的生产方法与应用 总被引：9，自引：0，他引：9
介绍了双氧水的５种生产方法及各自优缺点,并介绍了双氧水在纺织、化工行业、造纸、环保、电子、冶金、食品等行业的应用,指出国内企业应加快开发市场急需的Ｈ２Ｏ２及其下游产品。 相似文献
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对国内外煤与生物质热化学转化及微生物转化制氢工艺的研究现状及发展趋势进行了综述,分析了由煤和生物质制取氢气的工艺特点,指出了各种工艺的优势和不足。讨论了日本HyPr-RING工艺和美国FutureGen项目2种煤大规模制氢方案,给出了国内外煤与生物质制氢研究进展和现阶段的氢能选择。 相似文献
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根据双氧水的化学特性及蒽醌法双氧水生产工艺，对影响双氧水稳定的各种因素以及生产中的安全隐患进行了分析，提出了装置在建设、生产过程中的安全防范措施。 相似文献
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In gaseous products of biomass steam gasification, there exist a lot of CO, CH4 and other hydrocarbons that can be converted to hydrogen through steam reforming reactions. There exists potential hydrogen production from the raw gas of biomass steam gasification. In the present work, the characteristics of hydrogen production from biomass steam gasification were investigated in a small-scale fluidized bed. In these experiments, the gasifying agent (air) was supplied into the reactor from the bottom of the reactor and the steam was added into the reactor above biomass feeding location. The effects of reaction temperature, steam to biomass ratio, equivalence ratio (ER) and biomass particle size on hydrogen yield and hydrogen yield potential were investigated. The experimental results showed that higher reactor temperature, proper ER, proper steam to biomass ratio and smaller biomass particle size will contribute to more hydrogen and potential hydrogen yield. 相似文献
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Rui L. Mendes Jos P. Coelho Helena L. Fernandes Isabel J. Marrucho Joaquim M. S. Cabral Júlio M. Novais Antanio F. Palavra 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,62(1):53-59
A flow apparatus was constructed to carry out studies of supercritical fluid extraction in the temperature range 298·15–353·15 K and pressures up to 40 MPa. To test the apparatus, studies on the solubility of naphthalene in CO2 at 308·15, 313·15 and 318·15 K and pressures up to 35 MPa were carried out. These experimental data were correlated through the Peng–Robinson equation of state. Samples of the microalgae Botryococcus braunii and Chlorella vulgaris which produce diolefines C25–C31 and carotenoids, respectively, were submitted to supercritical CO2. The extraction yields for these compounds were studied and compared with those obtained using organic solvents. Supercritical CO2 was also used to produce extracts from rosemary leaves (Rosmarinus officinalis L.), which were compared with those obtained by hexane extraction. 相似文献