Izanlou Zahra, Akhavan Mahdavi Mahmood, Gheshlaghi Reza, Karimian Arash
Department of Chemical Engineering, Ferdowsi University of Mashhad, Azadi Square, Pardis Campus, 91779-48944, Mashhad, Iran.
Bioresour Bioprocess. 2023 Jul 22;10(1):44. doi: 10.1186/s40643-023-00664-1.
In this study, the sequential extraction of the three types of biochemicals from microalgae is employed, which is a more realistic and practical solution for large-scale extraction of bioproducts. The drying, grinding, organic solvent treatment, and ultra-sonication were combined to disrupt cells and sequentially extract bioproducts from three microalgae strains, Chlorella sorokiniana IG-W-96, Chlorella sp. PG-96, and Chlorella vulgaris IG-R-96. As the drying is the most energy-intensive step in cell disruption and sequential extraction, the effect of this step on sequential extraction deeply explored. The results show that total ash-plus contents of biochemicals in freeze-dried samples (95.4 ± 2.8%, 89.3 ± 3.9%, and 77.5 ± 4.2 respectively) are higher than those in oven-dried samples (91.0 ± 2.8%, 89.5 ± 3.0%, 71.4 ± 4.8%, respectively) showing the superiority of freeze drying over oven drying merely for Chlorella vulgaris IG-R-96 (p-value = 0.003) and non-significant variation for Chlorella sorokiniana IG-W-96 (p-value = 0.085) and Chlorella sp. PG-96 (p-value = 0.466). Variation among biochemical contents of strains is due to the difference in cell wall strength confirmed by TEM imaging. The freeze-dried samples achieved higher lipid yields than oven-dried samples. The total carbohydrate yields followed the same pattern. The extraction yields of total protein were higher in freeze-dried samples than in oven-dried. Total mass balance revealed that drying-based sequential extraction of value-added bioproducts could better demonstrate the economic potential of sustainable and renewable algal feedstock than independent assays for each biochemical.
在本研究中，采用了从微藻中顺序提取三种生化物质的方法，这是大规模提取生物制品更现实、更实用的解决方案。将干燥、研磨、有机溶剂处理和超声处理相结合，以破坏细胞，并从三种微藻菌株，即索氏小球藻IG-W-96、小球藻PG-96和普通小球藻IG-R-96中顺序提取生物制品。由于干燥是细胞破碎和顺序提取中最耗能的步骤，因此深入探讨了该步骤对顺序提取的影响。结果表明，冷冻干燥样品中生化物质的总灰分加含量（分别为95.4±2.8%、89.3±3.9%和77.5±4.2%）高于烘干样品（分别为91.0±2.8%、89.5±3.0%、71.4±4.8%），仅普通小球藻IG-R-96显示出冷冻干燥优于烘干（p值=0.003），而索氏小球藻IG-W-96（p值=0.085）和小球藻PG-96（p值=0.466）差异不显著。菌株生化含量的差异是由于通过透射电镜成像证实的细胞壁强度差异。冷冻干燥样品的脂质产量高于烘干样品。总碳水化合物产量遵循相同模式。冷冻干燥样品中总蛋白的提取率高于烘干样品。总质量平衡表明，基于干燥的增值生物制品顺序提取比每种生化物质的独立测定更能体现可持续和可再生藻类原料的经济潜力。
