Biomanufacturing
Biomanufacturing is a manufacturing process that utilizes biological systems, including living microorganisms, animal or plant cells, tissues, organelles, or enzymes, to produce commercially important biomaterials and chemical products, often through techniques such as fermentation, recombinant DNA technology, and advanced cell culture.[1] This approach leverages engineered or out-of-context biological entities to transform feedstocks like sugars or biomass into valuable outputs, distinguishing it from traditional chemical manufacturing by its reliance on biological mechanisms for synthesis, processing, or tool-based applications at commercial scales.[2][3] The field has evolved through distinct phases, beginning with early biomanufacturing 1.0 focused on primary metabolites like ethanol and butanol via simple mono-culture fermentation in the early 20th century.[1] This progressed to biomanufacturing 2.0 in the mid-20th century, emphasizing secondary metabolites such as antibiotics (e.g., penicillin) through mutant strains and aerobic processes during World War II.[1] By the 1970s, biomanufacturing 3.0 emerged with recombinant DNA techniques enabling the production of complex biomolecules like insulin and monoclonal antibodies using mammalian cell cultures.[1] Today, biomanufacturing 4.0 integrates synthetic biology, automation, and computational design to address global challenges, including sustainable production of biofuels, bioplastics, and even artificial organs.[1] Key applications span pharmaceuticals, where it produces biologics like vaccines and gene therapies; energy, through biofuels from engineered microbes; and materials science, yielding bio-based textiles, bioplastics, and composites such as synthetic spider silk for medical and protective uses.[2][4] In the U.S. economy, biomanufacturing contributes significantly, with a broad value added of approximately $438.8 billion in 2019, encompassing sectors like food processing, chemical manufacturing, and pharmaceuticals, while advanced biomanufacturing alone accounts for $94.6 billion and supports supply chain resilience and environmental sustainability by reducing reliance on fossil fuels.[5] Its growth is driven by innovations in upstream (feedstock and cell engineering), midstream (fermentation), and downstream (purification) processes, positioning it as a cornerstone of the bioeconomy for addressing food security, climate change, and health needs.[4][1]Overview
Definition and Scope
Biomanufacturing refers to the utilization of biological systems, such as living organisms including bacteria, yeast, and mammalian cells, or their components like enzymes, to produce commercial products through controlled biological processes at scale.[6][1] This approach leverages the natural capabilities of these systems to synthesize materials that may be difficult or inefficient to produce via traditional chemical methods, encompassing everything from therapeutic proteins to biofuels.[2] The scope of biomanufacturing spans an interdisciplinary integration of biology, engineering, and chemistry, enabling the design and optimization of processes that operate from laboratory-scale research and development to large-scale industrial production.[5] Key industries include biotechnology and pharmaceuticals for drug production, agriculture for bio-based fertilizers and pesticides, and energy for biofuels, contributing to sustainable manufacturing practices across these sectors.[7] Unlike synthetic biology, which primarily focuses on engineering novel biological systems and redesigning organisms for innovative functions, biomanufacturing emphasizes the scalable application of established biological platforms for commercial output.[8] Economically, biomanufacturing plays a pivotal role in the global bioeconomy, with the U.S. sector alone contributing an estimated $438.8 billion in value added as of 2019, supporting jobs and innovation in bio-based industries.[5] For instance, the global biologics market, a major subset of biomanufacturing, reached approximately $400 billion in 2024, underscoring its impact on healthcare and beyond.[9]Historical Development
The roots of biomanufacturing trace back to the 19th century, when scientific understanding of microbial processes laid the groundwork for controlled fermentation. In 1857, Louis Pasteur demonstrated that yeast, a living microorganism, was responsible for alcoholic fermentation, overturning earlier notions of spontaneous generation and establishing the biological basis for industrial-scale production of beverages and acids.[10] This discovery enabled the optimization of fermentation techniques for products like beer and wine, marking the transition from empirical practices to scientifically directed bioprocesses. By the early 20th century, these principles extended to antibiotics; in 1928, Alexander Fleming identified penicillin as a mold-derived substance that inhibited bacterial growth, though initial yields were too low for practical use.[11] During World War II, urgent demand for wound treatments spurred industrial scaling, with deep-tank fermentation methods achieving mass production by 1943, enabling the stockpiling of 2.3 million doses for the D-Day invasion in 1944 and scaling to produce approximately 2 million doses monthly by 1945 and saving countless lives.[12] Post-war advancements in the 1970s revolutionized biomanufacturing through genetic engineering. In 1973, Stanley Cohen and Herbert Boyer developed recombinant DNA technology, successfully cloning and expressing foreign DNA in Escherichia coli, which enabled the precise manipulation of microbial genomes for protein production.[13] This breakthrough led to the founding of Genentech in 1976 by Boyer and Robert Swanson, the first company dedicated to biotechnology, focusing on therapeutic proteins.[14] A pivotal milestone came in 1982, when the U.S. Food and Drug Administration approved Humulin, the first recombinant human insulin produced in bacteria, replacing animal-derived versions and demonstrating biomanufacturing's potential for safer, scalable pharmaceuticals.[15] These innovations shifted production from natural extracts to engineered systems, reducing costs and improving purity. In the 21st century, biomanufacturing evolved toward complex biologics and advanced genetic tools. The rise of monoclonal antibodies accelerated in the 2000s, with the 2006 FDA approval of panitumumab (Vectibix), the first fully human antibody generated via transgenic mouse technology, targeting epidermal growth factor receptor for colorectal cancer treatment and exemplifying reduced immunogenicity in therapeutics.[16] The 2010s introduced CRISPR-Cas9 for strain engineering, with early applications in 2016 enabling precise multiplex edits in industrial microbes like Clostridium acetobutylicum to boost metabolite yields, streamlining pathway optimization over traditional mutagenesis.[17] The COVID-19 pandemic highlighted rapid scale-up capabilities in 2020, as mRNA vaccines like Pfizer-BioNTech's BNT162b2 were produced at unprecedented speeds, reaching billions of doses through modular, continuous-like processes that integrated in vitro transcription and lipid nanoparticle formulation.[18] Throughout this era, the field transitioned from batch to continuous processing, with roots in 1940s fermentations but gaining traction in biopharma by the 2010s for higher efficiency and reduced footprint, as seen in intensified perfusion cultures.[19]Biological Foundations
Microorganisms and Cell Lines
Biomanufacturing relies on microorganisms and cell lines as the core biological agents for producing a wide array of biomolecules, from simple metabolites to complex proteins. Microorganisms, particularly bacteria, yeast, and fungi, are favored for their rapid growth rates, ease of genetic manipulation, and ability to perform large-scale fermentations. Bacteria such as Escherichia coli are extensively used for recombinant protein expression due to their fast doubling times (around 20-30 minutes), low cultivation costs, and well-characterized genetics, enabling high-yield production in simple media.[20] Yeast, exemplified by Saccharomyces cerevisiae, offers robustness in industrial fermentations, tolerance to harsh conditions like high ethanol concentrations, and generally recognized as safe (GRAS) status for food and pharmaceutical applications, making it ideal for ethanol and enzyme production.[21] Fungi like Aspergillus niger are employed for secreting enzymes and secondary metabolites, leveraging their filamentous growth for efficient substrate utilization in solid-state or submerged fermentations.[20] Eukaryotic cell lines provide essential capabilities for post-translational modifications absent in prokaryotes, such as glycosylation, which is critical for therapeutic efficacy. Mammalian cell lines, particularly Chinese hamster ovary (CHO) cells, dominate biomanufacturing, accounting for over 70% of approved biologics as of 2014 due to their ability to produce human-like glycoproteins with proper folding and assembly.[22] Insect cell lines, such as Spodoptera frugiperda-derived Sf9 cells, are widely used in the baculovirus expression vector system (BEVS) for producing viral vectors and complex proteins, offering high transient expression levels and scalability in serum-free media.[23] Plant cell lines, including tobacco-derived BY-2 cells, serve as platforms for vaccine antigens and recombinant proteins, benefiting from low contamination risks, eukaryotic modifications, and the ability to grow in contained bioreactors without animal-derived components.[24] Selection of microorganisms and cell lines in biomanufacturing prioritizes criteria such as product yield, genetic and phenotypic stability over multiple generations, and safety profiles to ensure regulatory compliance and process reliability. Yield is assessed through metrics like grams per liter of product, while stability involves monitoring expression consistency during scale-up; for instance, GRAS status is a key safety factor for yeast strains in food-grade applications, confirming no pathogenic risks.[25][21] Genetic engineering enhances these traits using tools like plasmids for transient expression in bacteria and CRISPR-Cas9 for precise knockouts or integrations to optimize metabolic pathways. A seminal example is the engineering of E. coli for human insulin production, revolutionizing therapeutic protein manufacturing.[26] Scaling these systems to industrial levels introduces challenges, including contamination risks from adventitious agents that can compromise product purity and safety, necessitating stringent sterile techniques and monitoring. Metabolic burdens from overexpressed pathways often lead to reduced growth rates, proteotoxic stress, and plasmid instability in engineered strains, limiting titers and requiring strategies like codon optimization or chaperone co-expression to redistribute cellular resources.[27][28] In mammalian and insect cell lines, shear sensitivity and nutrient limitations further exacerbate these issues during high-density cultures, demanding advanced bioreactor designs for viable scale-up.Enzymes and Biocatalysts
Enzymes serve as highly specific biological catalysts in biomanufacturing, enabling efficient, selective transformations in cell-free systems without the need for living cells. These biocatalysts, often isolated from natural sources or engineered, facilitate reactions under mild conditions, minimizing energy input and byproducts compared to chemical catalysis. In biomanufacturing, enzymes are integral to processes producing high-value compounds, such as chiral intermediates for pharmaceuticals and sustainable materials, by accelerating reactions with high regio- and stereoselectivity. Key enzyme classes include hydrolases and oxidoreductases, which dominate industrial applications due to their versatility. Hydrolases, such as lipases, catalyze the hydrolysis of ester bonds and are widely used in detergent formulations to degrade oily stains on fabrics, enhancing cleaning efficiency while reducing the need for harsh chemical surfactants. Oxidoreductases, exemplified by glucose oxidase, perform oxidation-reduction reactions and are essential in biosensors for precise glucose monitoring in medical diagnostics, where the enzyme selectively oxidizes glucose to gluconic acid, generating a detectable signal. These enzymes are predominantly derived from microbial sources, including bacteria and fungi, owing to their high yield and ease of genetic manipulation; for instance, Novonesis (formerly Novozymes) produces a portfolio of microbial enzymes like lipases and oxidoreductases for industrial biocatalysis.[29][30][31][32] Biocatalyst engineering enhances enzyme performance for demanding industrial conditions, employing directed evolution and rational design to improve properties like thermostability and activity. Directed evolution involves creating diverse mutant libraries through random mutagenesis or DNA shuffling, followed by high-throughput screening for variants with superior traits; this approach, pioneered by Frances Arnold, has revolutionized enzyme optimization and earned the 2018 Nobel Prize in Chemistry.[33] Rational design, in contrast, uses protein structure predictions to introduce targeted mutations, such as stabilizing disulfide bonds, to boost thermal resilience without compromising catalytic function. These methods collectively enable enzymes to withstand higher temperatures and pH extremes, broadening their biomanufacturing utility.[34][35] Immobilization techniques further optimize biocatalysts by anchoring enzymes to solid supports, promoting reusability and stability in flow reactors. Entrapment in alginate beads, formed by crosslinking sodium alginate with calcium ions, encapsulates enzymes in a biocompatible gel matrix, shielding them from denaturation while allowing substrate diffusion; this method is favored for its simplicity and low toxicity. Immobilization reduces operational costs by enabling multiple reaction cycles—up to 50% savings in some setups through minimized enzyme replacement and simplified recovery—while maintaining high activity retention, often exceeding 80% after several uses. Other approaches, like covalent binding to silica or magnetic nanoparticles, complement entrapment for specific applications, ensuring biocatalysts integrate seamlessly into scalable biomanufacturing workflows.[36][37][38] The efficiency of biocatalysts is quantitatively assessed through enzyme kinetics, governed by the Michaelis-Menten model for steady-state reactions. The reaction velocity v is given by: v = \frac{V_{\max} [S]}{K_m + [S]} where V_{\max} represents the maximum turnover rate, [S] is the substrate concentration, and K_m (the Michaelis constant) reflects the substrate concentration at half V_{\max}, indicating enzyme-substrate affinity. Lower K_m values denote higher affinity, crucial for low-substrate environments in biomanufacturing. Catalytic efficiency is further evaluated by the specificity constant k_{\cat} / K_m, where k_{\cat} (turnover number) measures substrate molecules converted per enzyme per second; this metric allows direct comparison of engineered variants, with values exceeding $10^6 \, \mathrm{M^{-1} s^{-1}} signaling high proficiency for industrial scalability. These parameters guide optimization, ensuring biocatalysts achieve rapid, selective conversions.[39][40] A prominent industrial example is the use of alpha-amylase and glucoamylase in starch hydrolysis for glucose syrup and biofuel production, where enzymatic processes operate at lower temperatures (50–60°C) than acid-based methods (requiring >100°C), yielding substantial energy savings while avoiding corrosive byproducts and corrosion. This biocatalytic route, commercialized since the 1960s, processes billions of tons of starch annually, demonstrating the economic and environmental advantages of enzymes in large-scale biomanufacturing.[41][42]Manufacturing Processes
Upstream Bioprocessing
Upstream bioprocessing encompasses the initial phases of biomanufacturing, where biological agents are cultivated to produce target biomolecules, emphasizing media formulation, inoculum development, and controlled growth in bioreactors to maximize yields. This stage is critical for establishing high-density cell cultures or microbial populations that serve as the foundation for subsequent production, with processes designed to mimic optimal physiological conditions while scaling from laboratory to industrial volumes. Key objectives include preventing contamination, ensuring nutrient availability, and mitigating inhibitory effects to achieve efficient biomass accumulation and product formation. Media preparation begins with the formulation of nutrient-rich solutions tailored to the biological system's requirements, typically incorporating carbon sources such as glucose for energy and nitrogen sources like yeast extract for amino acids and growth factors. These components are dissolved in water, often supplemented with salts, vitamins, and trace elements to support metabolic pathways, and the mixture is sterilized via autoclaving at 121°C for 15-20 minutes to eliminate microbial contaminants while preserving nutrient integrity. Inoculum development follows, starting with small-scale cultures in shake flasks—typically 100-500 mL volumes agitated at 200-300 rpm—to generate a viable cell population, which is then scaled up through successive transfers to larger vessels or seed bioreactors, maintaining a 5-10% inoculum volume to initiate main fermentation without shocking the cells. Cultivation occurs in three primary modes, each suited to different production goals and biological constraints. Batch cultivation involves adding all nutrients at the outset in a fixed volume, offering simplicity and ease of operation but risking substrate inhibition when high initial concentrations of carbon sources like glucose exceed 20-50 g/L, leading to reduced growth rates or byproduct accumulation. Fed-batch mode addresses this by initiating with a basal medium and exponentially feeding concentrated substrates—such as glucose at rates matching consumption (e.g., 1-5 g/L/h)—to sustain growth without inhibition; for Chinese hamster ovary (CHO) cells producing monoclonal antibodies, this strategy routinely achieves titers exceeding 10 g/L by extending culture duration to 12-14 days. Continuous cultivation, exemplified by the chemostat system, maintains steady-state conditions through constant inflow of fresh medium and outflow of culture broth at a dilution rate D (h⁻¹), where the specific growth rate \mu equals D (e.g., 0.1-0.3 h⁻¹ for bacteria), enabling prolonged operation but requiring stringent contamination controls. Optimization of cultivation parameters is essential for replicating laboratory success at scale, focusing on environmental controls to support metabolic efficiency. Dissolved oxygen (DO) is maintained at 80-100% air saturation via sparging and agitation to prevent hypoxia-induced stress, while pH is regulated between 6.8 and 7.2 using acid (e.g., HCl) or base (e.g., NaOH) additions, as deviations can alter enzyme activity and yield. Temperature is set at 30-37°C depending on the organism—lower for mammalian cells to favor productivity over growth—and monitored continuously. Advanced sensors, such as Raman spectroscopy probes, enable real-time, non-invasive tracking of metabolites like glucose and lactate by analyzing molecular vibrations, facilitating dynamic adjustments without sampling disruptions. Scale-up adheres to principles like maintaining constant volumetric oxygen transfer coefficient k_L a (typically 100-500 h⁻¹), ensuring equivalent oxygen supply across vessel sizes by matching power input per volume and impeller design. Yield metrics quantify process performance, guiding refinements in media and feeding strategies. Specific productivity q_p, defined as q_p = \frac{\Delta P}{X \cdot t} where \Delta P is the change in product concentration (e.g., pg/mL), X is viable cell density (cells/mL), and t is time (days), measures biomolecule output per cell per unit time, often reaching 10-50 pg/cell/day in optimized CHO fed-batch cultures. Biomass yield Y_{x/s}, calculated as grams of biomass produced per gram of substrate consumed (e.g., 0.4-0.5 g/g on glucose for bacteria), reflects resource efficiency, with values above 0.5 g/g indicating minimal wasteful metabolism and informing sustainable feed rates.Downstream Bioprocessing
Downstream bioprocessing encompasses the series of operations following upstream production to recover, purify, and formulate bioproducts, ensuring high purity and biological activity while addressing challenges like yield losses from impurities and aggregation. The process begins with harvesting, which separates the target bioproduct from cellular debris, spent media, and other solids generated during fermentation or cell culture. Common methods include centrifugation using disk-stack centrifuges operating at forces up to 10,000 g to efficiently remove whole cells in high-throughput industrial-scale operations.[43] Microfiltration, often as depth filtration, follows or complements centrifugation for further clarification, achieving flux rates exceeding 50 L/m²/h to remove residual particulates while retaining the soluble product.[43] To enhance efficiency, flocculation aids such as polymers are employed to aggregate cells and debris, facilitating easier separation and reducing the load on downstream equipment.[43] Purification steps refine the harvested material by exploiting differences in physicochemical properties to isolate the bioproduct at high purity levels, typically >99% for therapeutic applications. Affinity chromatography, particularly using Protein A ligands, serves as the primary capture step for monoclonal antibodies (mAbs), leveraging specific binding interactions with capacities of 30-50 g/L resin depending on the antibody and process conditions.[44] Subsequent polishing often involves ultrafiltration with diafiltration for buffer exchange and concentration, offering retention rates >99% for molecules larger than 10 kDa while minimizing product loss.[44] Hydrophobic interaction chromatography (HIC) is a key polishing technique for removing aggregates, achieving >90% clearance of dimers and high-molecular-weight species in flow-through mode, with monomer recoveries up to 98% at high load densities.[45] Formulation and stabilization prepare the purified bioproduct for storage and delivery, incorporating excipients to maintain structural integrity and prevent degradation. Lyophilization, or freeze-drying, is widely used for heat-sensitive biologics, involving freezing at shelf temperatures of -40°C followed by sublimation under vacuum pressures around 0.1 mbar to yield a stable dry powder.[46] Cryoprotectants like sucrose are added to formulations to shield proteins during freezing and drying, preserving native conformation and activity.[46] Sterility is ensured through final 0.2 μm filtration prior to filling, critical for parenteral biopharmaceuticals to eliminate microbial contaminants without compromising product integrity.[46] Throughout downstream bioprocessing, yield optimization is paramount, as overall recoveries for mAbs typically range from 50-80% due to losses in each unit operation from non-specific binding, aggregation, and incomplete separation.[44] These losses underscore the need for integrated process design to balance purity and productivity, with techniques like HIC playing a pivotal role in mitigating aggregate-related reductions without excessive yield penalties.[45]Products and Applications
Pharmaceutical Products
Biomanufacturing plays a pivotal role in the production of pharmaceutical products, particularly biologics, which are complex molecules derived from living organisms and account for a significant portion of modern therapeutics. These include monoclonal antibodies (mAbs), recombinant proteins, vaccines, and advanced therapies like cell and gene editing products, enabling targeted treatments for diseases such as cancer, autoimmune disorders, and genetic conditions. The complexity of these products arises from their large size, intricate structures, and the need for precise post-translational modifications, which necessitate specialized bioprocessing in mammalian cell systems to ensure efficacy and safety.[47] Monoclonal antibodies represent one of the largest classes of biologics produced via biomanufacturing, with adalimumab (marketed as Humira) serving as a prominent example for treating rheumatoid arthritis and other inflammatory conditions. Adalimumab, a recombinant human IgG1 mAb, is primarily manufactured using Chinese hamster ovary (CHO) cells, which allow for high-yield expression and proper folding of the antibody. The global market for adalimumab drugs was estimated at USD 14.96 billion in 2025, underscoring its commercial impact despite the rise of biosimilars. Recombinant proteins, such as erythropoietin (EPO), are another key biologic, produced recombinantly in CHO cells to treat anemia associated with chronic kidney disease and chemotherapy. These proteins mimic natural human hormones, with glycosylation in mammalian cells ensuring biological activity and extended half-life in vivo.[48][49][50] Vaccines produced through biomanufacturing have revolutionized infectious disease prevention, particularly with viral vectors and mRNA platforms. Adeno-associated virus (AAV) vectors are widely used for gene delivery in therapies targeting genetic disorders, achieving titers exceeding 10^13 vector genomes per milliliter (vg/mL) in optimized bioreactor processes to meet clinical demands. The Pfizer-BioNTech COVID-19 vaccine exemplifies mRNA technology, where synthetic mRNA encoding the SARS-CoV-2 spike protein is encapsulated in lipid nanoparticles for efficient cellular uptake and immune response induction. This platform's scalability in biomanufacturing facilities enabled rapid global deployment during the pandemic.[51][52] Advanced therapies further highlight biomanufacturing's innovation in personalization and precision medicine. Cell therapies, such as chimeric antigen receptor T-cell (CAR-T) products like Kymriah and Yescarta, involve autologous manufacturing where patient-derived T cells are engineered ex vivo to express CARs targeting cancer cells, but face challenges including variability in cell yields, lengthy production timelines (up to 3-4 weeks), and scalability due to individual patient processing. Gene editing products, such as Casgevy (exagamglogene autotemcel), approved by the FDA in 2023, utilize CRISPR/Cas9 technology to edit hematopoietic stem cells for treating sickle cell disease and beta-thalassemia, requiring stringent bioprocessing to maintain editing efficiency and cell viability. Production specifics for these pharmaceuticals emphasize the role of mammalian cells in achieving critical quality attributes, such as specific glycosylation patterns on mAbs that enhance effector functions like antibody-dependent cellular cytotoxicity for improved therapeutic efficacy. Batch sizes for mAb production typically range from 1,000 to 10,000 liters in fed-batch bioreactors, balancing yield with process control to produce grams-per-liter titers.[53][54][55][56]Food and Beverage Production
Biomanufacturing in food and beverage production leverages microbial fermentation to transform substrates into nutritious, flavorful, and preserved products, emphasizing scalable processes that enhance sensory qualities and nutritional profiles while minimizing resource use. This approach relies on selected or engineered microorganisms to produce key compounds like acids, alcohols, enzymes, and bioactive ingredients, integral to everyday consumables. Unlike pharmaceutical applications, food biomanufacturing prioritizes cost-effective, high-volume output with a focus on palatability and shelf stability.[57][58] Fermented foods exemplify traditional biomanufacturing, where microorganisms drive biochemical changes for texture, preservation, and flavor. In yogurt production, Lactobacillus species, particularly Lactobacillus delbrueckii subsp. bulgaricus in combination with Streptococcus thermophilus, ferment milk lactose into lactic acid at concentrations typically exceeding 1%, resulting in the product's coagulated structure and acidic taste essential for its probiotic benefits.[59][60] Cheese manufacturing employs microbial rennet, an enzyme complex produced by fungi such as Rhizomucor miehei through controlled fermentation, which efficiently coagulates milk proteins to form curds, offering a vegetarian alternative to animal-derived rennet with comparable yield and cheese quality.[61][62] For alcoholic beverages, Saccharomyces cerevisiae serves as the primary yeast, converting sugars in wort or must to ethanol with yields achieving 8-12% alcohol by volume (ABV) in beer and wine, influencing aroma compounds and fermentation efficiency.[63][64] Biomanufactured ingredients further expand food functionality, providing essential nutrients and enhancers via microbial metabolism. Monosodium glutamate (MSG), a widely used umami flavoring, is fermented from carbohydrates using Corynebacterium glutamicum, supporting an annual global production of approximately 3.5 million tons as of 2023 to meet demand in savory products.[65][66][67] Vitamin B12, vital for metabolic health, is industrially synthesized by Pseudomonas denitrificans in aerobic fermentations, yielding high-purity cyanocobalamin for fortification in plant-based and fermented foods.[68][69] Probiotic cultures like Bifidobacterium species are cultivated to achieve viabilities over 10^9 colony-forming units (CFU) per gram, ensuring sufficient live cells for gut health benefits when incorporated into dairy or non-dairy matrices.[70] Emerging novel foods harness precision fermentation to create sustainable alternatives, addressing dietary and environmental needs. In plant-based proteins, Pichia pastoris is engineered to produce soy leghemoglobin (heme), as in the Impossible Burger, where fermentation yields this iron-containing protein to replicate meat's bloody color, sizzle, and umami upon cooking.[71][72] Alternative sweeteners, such as steviol glycosides (e.g., rebaudioside A and M), are biosynthesized in yeasts like Saccharomyces cerevisiae or Yarrowia lipolytica, achieving titers up to 4 g/L and providing zero-calorie sweetness 200-400 times that of sucrose without aftertaste issues.[73][74] Safety in food biomanufacturing is ensured through rigorous evaluation, with many outputs classified under the FDA's Generally Recognized as Safe (GRAS) framework, affirming their innocuousness based on historical use or expert scientific consensus for intended applications.[75][76] Engineered microbial strains enable allergen-free production by excluding plant- or animal-derived allergens, such as in precision-fermented proteins that avoid soy or dairy traces, thereby reducing risks for allergic individuals while maintaining nutritional equivalence.[77][78]Industrial and Environmental Applications
Biomanufacturing plays a pivotal role in producing biofuels as sustainable alternatives to fossil fuels, leveraging microbial fermentation to convert biomass into energy carriers. Ethanol, a primary biofuel, is predominantly produced through the fermentation of sugars by Saccharomyces cerevisiae, with global production exceeding 110 billion liters annually.[79] This yeast's robustness and high ethanol tolerance make it ideal for large-scale operations, often using feedstocks like corn starch or sugarcane. Biodiesel, another key biofuel, is synthesized via enzymatic transesterification of vegetable oils or animal fats using lipases, which offer advantages over chemical catalysts by enabling reactions in milder conditions and simplifying glycerol recovery.[80] Advanced biofuels, such as isobutanol, are generated through metabolic engineering of Escherichia coli, achieving titers up to 50 g/L from cheese whey or glucose, enhancing compatibility with existing fuel infrastructure.[81] In the chemicals sector, biomanufacturing enables the production of platform chemicals that replace petroleum-derived equivalents, reducing reliance on non-renewable resources. Succinic acid, a versatile building block for polymers and solvents, is fermented by Anaerobiospirillum succiniciproducens under anaerobic conditions, offering a bio-based route that avoids petrochemical processes and supports a growing market valued at approximately $126 million for bio-succinic acid in 2023.[82] This bacterium efficiently converts glucose or glycerol into succinic acid at yields exceeding 1 g/g substrate, contributing to applications in biodegradable plastics and de-icing fluids.[83] Bioplastics like polyhydroxyalkanoates (PHAs) are accumulated intracellularly by Cupriavidus necator, which can store up to 77% PHA as a percentage of cell dry weight from various carbon sources, providing a biodegradable alternative to conventional plastics with conversion efficiencies reaching 0.3–0.5 g PHA per g biomass in optimized fed-batch processes.[84] Environmental applications of biomanufacturing harness microbial and enzymatic systems for pollution mitigation and resource-efficient processing. Bioremediation employs bacteria like Pseudomonas species to degrade oil hydrocarbons, with strains such as P. aeruginosa capable of removing up to 95% of petroleum contaminants in contaminated soils or water through secreted biosurfactants and enzymes.[85] Enzyme-based biosensors detect environmental pollutants, such as heavy metals or pesticides, by integrating oxidases or dehydrogenases with electrochemical transducers for real-time, sensitive monitoring at concentrations as low as parts per billion.[86] In the textile industry, cellulase enzymes facilitate bio-stoning for denim finishing, replacing abrasive pumice stones and reducing water consumption by up to 90% while minimizing wastewater generation.[87] Scalability in biomanufacturing is advanced by transitioning to lignocellulosic feedstocks, such as agricultural residues, through enzymatic hydrolysis pretreatments that break down complex polymers into fermentable sugars. Cellulase cocktails hydrolyze pretreated biomass like corn stover, achieving glucose yields over 90% and enabling cost-effective biofuel and chemical production in integrated biorefineries.[88] This shift supports sustainable practices by utilizing non-food biomass, with ongoing optimizations in enzyme blends and process integration to overcome recalcitrance and improve overall economics.[89]Facilities and Infrastructure
Equipment and Bioreactors
Biomanufacturing relies on specialized equipment to cultivate microorganisms, mammalian cells, or enzymes under controlled conditions, with bioreactors serving as the central vessels for these processes. These systems must ensure efficient mixing, oxygen transfer, and nutrient distribution while minimizing contamination risks. Key designs include stirred-tank, airlift, and single-use bioreactors, each optimized for specific cell types and production scales.[90] Stirred-tank bioreactors (STRs) are the most widely adopted in industrial biomanufacturing due to their versatility and scalability. They feature mechanical impellers, such as Rushton turbines for high-shear microbial cultures or pitched-blade impellers for low-shear mammalian cells, which promote uniform mixing and gas dispersion. Oxygen transfer efficiency in STRs is characterized by the volumetric mass transfer coefficient (k_L a), typically exceeding 100 h⁻¹ under optimized conditions with sparging and agitation, enabling high-density cultures.[90][91] Airlift bioreactors, in contrast, use gas injection to drive circulation through a draft tube, creating buoyancy-induced mixing without mechanical parts. This design generates low shear stress, making it suitable for fragile mammalian or plant cells that are sensitive to agitation. While k_L a values are generally lower than in STRs (often 50–200 h⁻¹), airlift systems offer energy efficiency and ease of sterilization, though scaling remains challenging due to variable flow patterns.[90][92] Single-use bioreactors (SUBs) employ disposable plastic bags within a support frame, often with rocking or impeller-based mixing to achieve low shear. They eliminate the need for cleaning-in-place (CIP) procedures, reducing turnaround time between batches by avoiding multi-hour cleaning cycles and lowering cross-contamination risks. SUBs scale from small laboratory units (e.g., 1 L) to production volumes up to 6,000 L as of 2025, with performance comparable to stainless-steel counterparts, though they introduce plastic waste concerns.[90][93][94]| Bioreactor Type | Mixing Mechanism | Shear Stress | Typical k_L a (h⁻¹) | Key Advantages |
|---|---|---|---|---|
| Stirred-Tank | Mechanical impellers | High (microbial) to low (mammalian) | >100 | Scalable, versatile control |
| Airlift | Gas-driven circulation | Low | 50–200 | Energy-efficient, shear-sensitive cells |
| Single-Use | Rocking or impellers in bags | Low | 50–300 | No CIP, fast setup |