Cultivation of microalgae using organic compost as nutrient source for biomolecules extraction via multiphase partitioning techniques

Microalgae have been gaining attention as a sustainable third-generation feedstock for biofuel and bioproducts production due to their high products yield and renewability compared to other plant sources. Nevertheless, the production of biofuels and valuable compounds from microalgae does not perform well in terms of an economic and environmental perspective. The cultivation of microalgae requires large amounts of freshwater and nutrients, leading to high operating costs. There is a need to find alternative sources which could potentially promote the recycling the nutrients for renewable feedstock cultivation. Utilization of these waste sources could alleviate the global resource crisis and contribute to better nutrient use efficiencies. Besides that, the conventional processes used for extracting biomolecules from microalgae are not efficient and requires evaluation on the feasibility. Most of the processes involves the isolation, concentration and purification steps that uses high amount of chemicals and expensive equipment, hence contributing to the high total cost of producing valuable compounds from microalgae. This raises the significance of developing approaches to reduce the cost and increase efficiency in both the cultivation of microalgae and extraction techniques for biomolecules production. This thesis presents the ultimate goal of discovering and developing a sustainable processing for the cultivation and biomolecules extraction from microalgae. The sustainable approaches include the discovery of an alternative nutrient source for the cultivation of microalgae, utilization of uprising bioseparation techniques for effective biomolecules extraction and purification, as well as the subsequent value-added products generation from the combination of various waste sources. This thesis discusses the use of food waste compost as an organic medium for microalgae cultivation. Food waste compost solution has the potential to partially substitute a portion of the inorganic medium and have shown to produce better biomass production rate (11.1% increase) and higher biochemical content (10.1% higher lipid and 2.0% higher protein content) in the biomass. This thesis also presents the use of two multiphase partitioning techniques, namely microwave-assisted three phase partitioning (MWTPP) and liquid biphasic flotation (LBF), for the extraction and purification of proteins and pigments, respectively. These techniques are simple and easy to operate, rapid processing, environmentally friendly, produce high yield and separation efficiency, and are potential to be scaled-up without difficulty. The utilization of these multiphase separation processes has shown promising extraction of valuable biomolecules from microalgae. MWTPP has successfully recovered 63.2% of proteins from Chlorella microalgae and LBF has purified 90.4% of C-phycocyanin from Spirulina microalgae. Moreover, this thesis illustrates the densification of food waste compost with dairy waste powder as an effective approach for producing value-added compounds using waste sources. The densification was done through pelletizing the compost with waste additive into pellets that are easier for handling, transportation and management. Lastly, the research achievement in these works and the future opportunities for further works are highlighted in the later parts of this thesis

Ultrasound-Assisted Food Processing: A Mini Review of Mechanisms, Applications, and Challenges

Ultrasound technology in food processing holds promise in terms of energy efficiency, environmental impact, and sustainability compared to traditional processing methods. These conventional heat-based techniques, such as salting, smoking, and frying, are energy-intensive and time-consuming. Therefore, ultrasound as a promising technology has attracted the interest of scientists and stakeholders in the food processing field. This alternative solution utilizes ultrasound and can achieve similar results with reduced energy input. This not only reduces energy consumption but also contributes to reducing carbon footprint and greenhouse gas emissions. In addition, ultrasound processing technology enhances food safety and quality by inhibiting microbial growth and killing pathogens, leading to longer shelf life and reduced food waste. However, there are also present some limitations of ultrasound in food processing through dense and complex food matrices like protein. Current research and development efforts are expected to address these challenges and expand applications in food processing. Overall, ultrasonic technology could transform the sustainability of food processing in the future

The Future of Food Preservation: Active Packaging with Controlled Release Systems

This report provides an overview of active packaging with a focus on controlled release packaging (CRP) technologies, which have been developed to improve the shelf life of food products. Active packaging systems incorporate various functional components such as antimicrobial agents or oxygen scavengers into package material to maintain product quality during storage. CRP technology involves encapsulating bioactive compounds within a carrier matrix that can be released in a controlled manner over time. The paper compares these two promising technologies and highlights their advantages for extending shelf life while maintaining product quality. While active packaging is more suitable for short-term preservation due to non-controllable active agent release, CRP has potential applications in long-term preservation due to its ability to provide sustained release of bioactive compounds. Future prospects include developing a blend of CRP and intelligent food packaging. However, challenges remain including the sustainable release rate of the active agents from the packaging into the headspace or food surface. Overall, this review provides insights into the current state-of-the-art research on CRP technologies while highlighting future directions for improving food safety through innovative approaches aimed at preserving freshness while minimizing waste generation from expired products

From Kimchi to Kefir: An Exploration of Probiotics, Benefits, and Future

Live microorganisms known as probiotics, which have various beneficial claims, have undergone substantial research and commercial exploration in a wide range of goods across the world. Many scientific studies have demonstrated their advantages for both human and animal health. The two primary probiotic bacterial species are Lactobacillus sp. and Bifidobacterium sp. The multi-billion health food industry has employed probiotics with a variety of dietary matrices, which are briefly reported. The history of probiotics, their use in food and medicine, and the latest developments in probiotic processes such as microencapsulation and genetically engineered probiotics are all covered in this review

Climate-Conscious Food Preserving Technologies for Food Waste Prevention

Global food production is responsible for around 26% of greenhouse gas emissions caused by human activities. Notably, 6% of these emissions are caused by unconsumed food. Both traditional and current climate-conscious technologies for food preservatives that assure food waste reduction are discussed. This review investigates the potential of smart packaging biosensors and natural antimicrobial agents in fostering environmentally friendly, cutting-edge food systems. Specifically, it highlights the studies that explore the use of natural antimicrobial agents of calcined corals in active packaging systems for storing milk. The finding revealed that this method had a significant impact on maximizing the shelf life of fresh food. Furthermore, this review discusses the concept of smart packaging of food, focusing on biopolymer-based nanocomposites and biosensors, which have gained increasing attention in the food industry due to concerns about food safety and quality. The review also examines the efforts of the United Arab Emirates (UAE) to combat food waste through the initiatives such as UAE Food Bank, Winnow, and Ne’ma which is the national food loss and waste project. These technologies and practices have the potential to guarantee food safety, preserve quality, and reduce waste, but there are still issues with cost, biocompatibility, and consumer acceptance

Polymer-salt interaction

Up to this moment, an uprising demand in downstream processing by incorporate innovative, effective, and reliable extraction methods as plenty effort and progression in the upstream production have led to advancement in the biomanufacturing industry. Previously, deployment of conventional downstream technologies has been a hindrance due to high cost, time-consuming, low yield, detrimental, noneco-friendly, lack of simplicity, and difficulties in scaling-up. A new emerging liquid–liquid extraction technology by means the polymer–salt aqueous two phases system for the recovery of biomolecules such as proteins, DNA, and nucleic acids, virus-like particles, and drug residues in food and water. Moreover, the partition coefficient of polyethylene glycol (PEG) 6000-phosphate aqueous two-phase system (ATPS) increased by 62-fold by adding NaCl which results in the recovery of proteins from 90% to 95% in a single purification step. Besides, plasmid DNA successfully recovered by 67% in the PEG-rich phase and managed to partition the contaminants toward the salt-rich phase. The total recovery of 90% from the separation of adenoviral vectors in HEK 293 cells using PEG-ammonium sulfate ATPS. In addition, the recovery of drug residues from food and water corresponds to recovery rate of 96%–100% which is safe for human consumption. This review discusses the following basic mechanism and working principles of ATPS. Factors affecting the partitioning behavior of biomolecules for instance, PEG molecular weight, PEG concentration, system pH, effect of temperature, hydrophobicity, and addition of salt are presented. Future consideration and modification to allow further improvement toward reliable large-scale extraction and purification of biomolecules

Liquid biphasic flotation for the purification of C-phycocyanin from Spirulina platensis microalga

Liquid biphasic flotation (LBF), an integrated process of liquid biphasic system (LBS) and adsorptive bubbles flotation, was used for the purification of C-phycocyanin from S. platensis microalgae. Various experimental parameters such as type of phase forming polymer and salt, concentration of phase forming components, system pH, volume ratio, air flotation time and crude extract concentration were evaluated to maximise the C-phycocyanin recovery yield and purity. The optimal conditions for the LBF system achieving C-phycocyanin purification fold of 3.49 compared to 2.43 from the initial LBF conditions was in polyethylene glycol (PEG) 4000 and potassium phosphate combination, with 250 g/L of polymer and salt concentration each, volume ratio of 1:0.85, system pH of 7.0, air flotation duration of 7 min and phycocyanin crude extract concentration of 0.625 %w/w. The LBF has effectively enhanced the purification of C-phycocyanin in a cost effective and simple processing

Advances in delivery methods of Arthrospira platensis (spirulina) for enhanced therapeutic outcomes

Arthrospira platensis (A. platensis) aqueous extract has massive amounts of natural products that can be used as future drugs, such as C-phycocyanin, allophycocyanin, etc. This extract was chosen because of its high adaptability, which reflects its resolute genetic composition. The proactive roles of cyanobacteria, particularly in the medical field, have been discussed in this review, including the history, previous food and drug administration (FDA) reports, health benefits and the various dose-dependent therapeutic functions that A. platensis possesses, including its role in fighting against lethal diseases such as cancer, SARS-CoV-2/COVID-19, etc. However, the remedy will not present its maximal effect without the proper delivery to the targeted place for deposition. The goal of this research is to maximize the bioavailability and delivery efficiency of A. platensis constituents through selected sites for effective therapeutic outcomes. The solutions reviewed are mainly on parenteral and tablet formulations. Moreover, suggested enteric polymers were discussed with minor composition variations applied for better storage in high humid countries alongside minor variations in the polymer design were suggested to enhance the premature release hindrance of basic drugs in low pH environments. In addition, it will open doors for research in delivering active pharmaceutical ingredients (APIs) in femtoscale with the use of various existing and new formulations. Abbrevations: SDGs; Sustainable Development Goals, IL-4; Interleukin-4, HDL; High-Density Lipoprotein, LDL; Low-Density Lipoprotein, VLDL; Very Low-Density Lipoprotein, C-PC; C-Phycocyanin, APC; Allophycocyanin, PE; Phycoerythrin, COX-2; Cyclooxygenase-2, RCTs; Randomized Control Trials, TNF-α; Tumour Necrosis Factor-alpha, γ-LFA; Gamma-Linolenic Fatty Acid, PGs; Polyglycans, PUFAs: Polyunsaturated Fatty Acids, NK-cell; Natural Killer Cell, FDA; Food and Drug Administration, GRAS; Generally Recognized as Safe, SD; Standard Deviation, API; Active Pharmaceutical Ingredient, DW; Dry Weight, IM; Intramuscular, IV; Intravenous, ID; Intradermal, SC; Subcutaneous, AERs; Adverse Event Reports, DSI-EC; Dietary Supplement Information Executive Committee, cGMP; Current Good Manufacturing Process, A. platensis; Arthrospira platensis, A. maxima; Arthrospira maxima, Spirulina sp.; Spirulina species, Arthrospira; Spirulina, Tecuitlatl; Spirulina, CRC; Colorectal Cancer, HDI; Human Development Index, Tf; Transferrin, TfR; Transferrin Receptor, FR; Flow Rate, CPP; Cell Penetrating Peptide, SUV; Small Unilamenar Vesicle, LUV; Large Unilamenar Vesicle, GUV; Giant Unilamenar Vesicle, MLV; Multilamenar Vesicle, COVID-19; Coronavirus-19, PEGylated; Stealth, PEG; Polyethylene Glycol, OSCEs; Objective Structured Clinical Examinations, GI; Gastrointestinal Tract, CAP; Cellulose Acetate Phthalate, HPMCP, Hydroxypropyl Methyl-Cellulose Phthalate, SR; Sustained Release, DR; Delay Release, Poly(MA-EA); Polymethyl Acrylic Co-Ethyl Acrylate, f-DR L-30 D-55; Femto-Delay Release Methyl Acrylic Acid Co-Ethyl Acrylate Polymer, MW; Molecular Weight, Tg; Glass Transition Temperature, SN2; Nucleophilic Substitution 2, EPR; Enhance Permeability and Retention, VEGF; Vascular Endothelial Growth Factor, RGD; Arginine-Glycine-Aspartic Acid, VCAM-1; Vascular Cell Adhesion Molecule-1, P; Coefficient of Permeability, PES; Polyether Sulfone, pHe; Extracellular pH, ζ-potential; Zeta potential, NTA; Nanoparticle Tracking Analysis, PB; Phosphate Buffer, DLS; Dynamic Light Scattering, AFM; Atomic Force Microscope, Log P; Partition Coefficient, MR; Molar Refractivity, tPSA; Topological Polar Surface Area, C log P; Calculated Partition Coefficient, CMR; Calculated Molar Refractivity, Log S; Solubility Coefficient, pka; Acid Dissociation Constant, DDAB; Dimethyl Dioctadecyl Ammonium Bromide, DOPE; Dioleoylphosphatidylethanolamine, GDP; Good Distribution Practice, RES; Reticuloendothelial System, PKU; Phenylketonuria, MS; Multiple Sclerosis, SLE; Systemic Lupus Erythematous, NASA; National Aeronautics and Space Administration, DOX; Doxorubicin, ADRs; Adverse Drug Reactions, SVM; Support Vector Machine, MDA; Malondialdehyde, TBARS; Thiobarbituric Acid Reactive Substances, CRP; C-Reactive Protein, CK; Creatine Kinase, LDH; Lactated Dehydrogenase, T2D; Type 2 Diabetes, PCB; Phycocyanobilin, PBP; Phycobiliproteins, PEB; Phycoerythrobilin, DPP-4; Dipeptidyl Peptidase-4, MTT; 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide, IL-2; Interleukin-2, IL-6; Interleukin-6, PRISMA; Preferred Reporting Items for Systematic Reviews and Meta-Analyses, STATA; Statistics, HepG2; Hepatoblastoma, HCT116; Colon Cancer Carcinoma, Kasumi-1; Acute Leukaemia, K562; Chronic Leukaemia, Se-PC; Selenium-Phycocyanin, MCF-7; Breast Cancer Adenocarcinoma, A375; Human Melanoma, RAS; Renin-Angiotensin System, IQP; Ile-Gln-Pro, VEP; Val-Glu-Pro, Mpro; Main Protease, PLpro; Papin-Like Protease, BMI; Body Mass Index, IC50; Inhibitory Concentration by 50%, LD50; Lethal Dose by 50%, PC12 Adh; Rat Pheochromocytoma Cells, RNS; Reactive Nitrogen Species, Hb1Ac; hemoglobin A1c.- Malaysia Fundamental Research Grant Scheme [grant number: FRGS/1/2019/STG05/UNIM/02/2] and MyPAIR-PHC-Hibiscus Grant [grant number: MyPair/1/2020/STG05/UNIM/1]. - Xiamen University Malaysia (XMUM) under the XMUM Research Fund (Grant number: XMUMRF/2021-C7/IENG/0033) and Hengyuan International Sdn. Bhd

Cultivation of microalgae using organic compost as nutrient source for biomolecules extraction via multiphase partitioning techniques

Microalgae have been gaining attention as a sustainable third-generation feedstock for biofuel and bioproducts production due to their high products yield and renewability compared to other plant sources. Nevertheless, the production of biofuels and valuable compounds from microalgae does not perform well in terms of an economic and environmental perspective. The cultivation of microalgae requires large amounts of freshwater and nutrients, leading to high operating costs. There is a need to find alternative sources which could potentially promote the recycling the nutrients for renewable feedstock cultivation. Utilization of these waste sources could alleviate the global resource crisis and contribute to better nutrient use efficiencies. Besides that, the conventional processes used for extracting biomolecules from microalgae are not efficient and requires evaluation on the feasibility. Most of the processes involves the isolation, concentration and purification steps that uses high amount of chemicals and expensive equipment, hence contributing to the high total cost of producing valuable compounds from microalgae. This raises the significance of developing approaches to reduce the cost and increase efficiency in both the cultivation of microalgae and extraction techniques for biomolecules production. This thesis presents the ultimate goal of discovering and developing a sustainable processing for the cultivation and biomolecules extraction from microalgae. The sustainable approaches include the discovery of an alternative nutrient source for the cultivation of microalgae, utilization of uprising bioseparation techniques for effective biomolecules extraction and purification, as well as the subsequent value-added products generation from the combination of various waste sources. This thesis discusses the use of food waste compost as an organic medium for microalgae cultivation. Food waste compost solution has the potential to partially substitute a portion of the inorganic medium and have shown to produce better biomass production rate (11.1% increase) and higher biochemical content (10.1% higher lipid and 2.0% higher protein content) in the biomass. This thesis also presents the use of two multiphase partitioning techniques, namely microwave-assisted three phase partitioning (MWTPP) and liquid biphasic flotation (LBF), for the extraction and purification of proteins and pigments, respectively. These techniques are simple and easy to operate, rapid processing, environmentally friendly, produce high yield and separation efficiency, and are potential to be scaled-up without difficulty. The utilization of these multiphase separation processes has shown promising extraction of valuable biomolecules from microalgae. MWTPP has successfully recovered 63.2% of proteins from Chlorella microalgae and LBF has purified 90.4% of C-phycocyanin from Spirulina microalgae. Moreover, this thesis illustrates the densification of food waste compost with dairy waste powder as an effective approach for producing value-added compounds using waste sources. The densification was done through pelletizing the compost with waste additive into pellets that are easier for handling, transportation and management. Lastly, the research achievement in these works and the future opportunities for further works are highlighted in the later parts of this thesis

Special Issue on “New Processes: Working towards a Sustainable Society”

The idea of a sustainable society comprises a consumer society that considers the welfare of the planet for future generations [...