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How Far Has the Development for Industrial Internet of Things (IoT) in Microalgae?
Published in Pau Loke Show, Wai Siong Chai, Tau Chuan Ling, Microalgae for Environmental Biotechnology, 2023
Vimal Angela Thiviyanathan, Hooi Ren Lim, Pei En Tham, Pau Loke Show
The next step in the downstream production is the extraction of the biomolecules from the cells. Microalgae biomolecules such as lipids, polysaccharides, amino acids, pigments, and carotenoids (Kumar et al., 2021) are reported to be useful in many industries (Sydney et al., 2019). Currently, more attention is given to the extraction of lipids from microalgae as lipids have a high potential in the biodiesel and the pharmaceutical industry (Huang et al., 2016; Goh et al., 2019). This statement is well supported by the report published by the Global Banking and Finance Review that states that the algae biofuel market is forecasted to reach a value of USD 10193.8 million by 2027 (Global Banking and Finance, 2021). Though the demand for microalgae lipids is showing an increasing trend across the years (Brindhadevi et al., 2021; Enamala et al., 2018), there are still many areas that can be improved to optimise the extraction process. The extraction of microalgae biomolecules begins with cell disruption (Dixon and Wilken, 2018). Cell disruption is a process where the cellular membranes of the cells are disintegrated to facilitate extraction (Corrêa et al., 2021). Some examples of cell disruption methods include bead milling, homogenisation (high or low speed), ultrasonication, irradiation, autoclaving, and using pulsed electric fields.
Microbial Lipids as Diesel Replacement:
Published in Farshad Darvishi Harzevili, Serge Hiligsmann, Microbial Fuels, 2017
Hatim Machrafi, Christophe Minetti, Carlo Saverio Iorio
Since algae are rich in chemical and biological molecules with attractive properties, they should be properly released by a rapid and effective cell disruption process, in order to maximize the value of extracted products without harming or, in the case of proteins, denaturing them. More information can be found on downstream processing in Probst et al. (2015), Lesage and Bussey (2006), and Angles et al. (2017). Lysis is a method that conditions the cell in such a way that the tough, outer wall gets disrupted. There are a huge variety of cell disruption methods, and they can be divided into mechanical and nonmechanical.
Nanobiotechnology Advances in Bioreactors for Biodiesel Production
Published in Madan L. Verma, Nanobiotechnology for Sustainable Bioenergy and Biofuel Production, 2020
Bhaskar Birru, P. Shalini, Madan L. Verma
The cell disruption is the initial step in the extraction process after harvesting microalgae biomass. The cell disruption methods can be classified into chemical, biological and mechanical methods. Chemical treatments and osmotic shock could be used as a chemical method. Various enzymes are involved in the extraction process in the degradation of complex glycoproteins and carbohydrates. The mechanical methods include ultra-sonication, microwave, electroporation, bead beating and high-pressure homogenization (Günerken et al. 2015).
In-situ transesterification of single-cell oil for biodiesel production: a review
Published in Preparative Biochemistry & Biotechnology, 2023
Tasneem Gufrana, Hasibul Islam, Shivani Khare, Ankita Pandey, Radha P.
Cell disruption is a form of biomass pretreatment method employed to disturb the cellular composition in microorganisms to obtain the internal biological components, especially lipids. The understanding of the cell wall is important as it helps in identifying a suitable pretreatment method to disrupt the cellular framework. The yeast cell wall consists of polysaccharides like mannans and glucans, and beneath it lies a protein layer. This composition makes the cell wall thicker that tends to restrict the solvent’s entry into the product of interest. The cell wall composition of bacteria varies due to the presence of peptidoglycan in the case of gram-positive and lipopolysaccharide in the case of gram-negative. Also, the cell wall structure in photosynthetic microalgae consists of complex carbohydrates and glycoproteins that make it thicker. Mechanical and non-mechanical methods are the major two sub-divisions of cell disruption.
A review of microalgal cell wall composition and degradation to enhance the recovery of biomolecules for biofuel production
Published in Biofuels, 2023
Syafiqah Md Nadzir, Norjan Yusof, Norazela Nordin, Azlan Kamari, Mohd Zulkhairi Mohd Yusoff
Non-mechanical cell disruption methods are divided into three primary groups – physical, chemical, and biological – based on the approach employed to disrupt the cells. Non-mechanical techniques are known as gentle methods since they are less harsh towards cells and provide greater specificity and selectivity than mechanical methods. Non-mechanical methods also require less energy than mechanical methods [8]. Non-mechanical disruption is preferable for species with weak cell walls such as Dunaliella sp. and Isochrysis sp., since it requires less time and resources than mechanical disruption [91]. In addition, non-mechanical methods can target certain cells and/or molecules without contaminating the lysate with impurities or other unwanted compounds.
A review on microalgae biofuel and biorefinery: challenges and way forward
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2020
Lakhan Kumar, Navneeta Bharadvaja
Cell disruption techniques, mainly chemical and mechanical, pose threats to native structure and functionality of various cellular components. Protein is highly sensitive to temperature and pH. Mechanical and chemical methods alter the temperature and pH and thus destabilize the proteins in disrupted cell biomass. Thus, techniques performed under mild conditions (i.e. low shear and low temperature) to break cell walls and membranes for release of intracellular components in their native structure without any modification or alternation in their functional properties are needed to develop (Lee et al. 2017). Cell disruption techniques having a high yield of desired particle size in lesser treatment time, energy and cost would significantly increase the economic viability of microalgal biorefinery. When the cell breaks into ultra-small particles, they form stable emulsions or dispersions. It makes the fractionation or purification of the different cellular components a difficult process. Pulsed electric field (PEF), though it has lesser yield as compared to mechanical disruption such as High-Pressure Homogenizer (HPH) or bead mill, for cell disruption can be performed with prior pre-treatment of algal cells to break down the outer strong cell wall and membrane (Goettel et al. 2013). PEF method being mild and selective in nature facilitates release of intact proteins and other intracellular components (‘T Lam et al. 2017). Complete understanding of chemical structure and composition of microalgal cell wall and membrane could bring affirmation for mechanical cell disruption method and selection of pre-treatment methods if needed (Lee et al. 2017). Ultrasound, supersonic flow fluid processing, and enzymatic treatment are also very promising cell disruption techniques for the microalgal biorefinery perspective. Mechanical disruption methods are more promising than any other available technique in terms of yield but with reduced functionality and bioavailability of various most sought after high-value cellular components (Bleakley and Hayes 2017). Safi et all. (Safi et al. 2017) studied the overall process performance for protein extraction from Nannochloropsis species targeting cell disruption and separation of protein from cell lysate. Results showed that homogenization was more efficient than enzymatic treatment for cell disruption while the overall result for homogenization was less as compared to enzymatic treatment coupled with separation strategies adopted (Safi et al. 2017). Development of less shear and low-temperature mechanical cell disruption techniques ambient to most cellular components can sufficiently address the limitations of their application in microalgal biorefinery (T’ Lam et al. 2018).