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1.
NPJ Sci Food ; 8(1): 23, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38693150

RESUMEN

Cultivated meat production requires bioprocess optimization to achieve cell densities that are multiple orders of magnitude higher compared to conventional cell culture techniques. These processes must maximize resource efficiency and cost-effectiveness by attaining high cell growth productivity per unit of medium. Microcarriers, or carriers, are compatible with large-scale bioreactor use, and offer a large surface-area-to-volume ratio for the adhesion and proliferation of anchorage-dependent animal cells. An ongoing challenge persists in the efficient retrieval of cells from the carriers, with conflicting reports on the effectiveness of trypsinization and the need for additional optimization measures such as carrier sieving. To surmount this issue, edible carriers have been proposed, offering the advantage of integration into the final food product while providing opportunities for texture, flavor, and nutritional incorporation. Recently, a proof of concept (POC) utilizing inactivated mycelium biomass derived from edible filamentous fungus demonstrated its potential as a support structure for myoblasts. However, this POC relied on a model mammalian cell line combination with a single mycelium species, limiting realistic applicability to cultivated meat production. This study aims to advance the POC. We found that the species of fungi composing the carriers impacts C2C12 myoblast cell attachment-with carriers derived from Aspergillus oryzae promoting the best proliferation. C2C12 myoblasts effectively differentiated on mycelium carriers when induced in myogenic differentiation media. Mycelium carriers also supported proliferation and differentiation of bovine satellite cells. These findings demonstrate the potential of edible mycelium carrier technology to be readily adapted in product development within the cultivated meat industry.

2.
Front Immunol ; 14: 1199747, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37638040

RESUMEN

Multiple Sclerosis (MS) is a chronic neurodegenerative disease with limited therapeutic options. Recombinant Fc multimers (rFc), designed to mirror many of the anti-inflammatory activities of Intravenous Immunoglobulin (IVIG), have been shown to effectively treat numerous immune-mediated diseases in rodents. In this study we used the experimental autoimmune encephalomyelitis (EAE) murine model of MS to test the efficacy of a rFc, M019, that consists of multimers of the Fc portion of IgG2, in inhibiting disease severity. We show that M019 effectively reduced clinical symptoms when given either pre- or post-symptom onset compared to vehicle treated EAE induced mice. M019 was effective in reducing symptoms in both SJL model of relapsing remitting MS as well as the B6 model of chronic disease. M019 binds to FcγR bearing-monocytes both in vivo and in vitro and prevented immune cell infiltration into the CNS of treated mice. The lack of T cell infiltration into the spinal cord was not due to a decrease in T cell priming; there was an equivalent frequency of Th17 cells in the spleens of M019 and vehicle treated EAE induced mice. Surprisingly, there was an increase in chemokines in the sera but not in the CNS of M019 treated mice compared to vehicle treated animals. We postulate that M019 interacts with a FcγR rich monocyte intermediary to prevent T cell migration into the CNS and demyelination.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Enfermedades Neurodegenerativas , Animales , Ratones , Esclerosis Múltiple/tratamiento farmacológico , Modelos Animales de Enfermedad , Receptores de IgG
3.
Eng Life Sci ; 23(8): e2300005, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37533728

RESUMEN

In this work, we applied a multi-information source modeling technique to solve a multi-objective Bayesian optimization problem involving the simultaneous minimization of cost and maximization of growth for serum-free C2C12 cells using a hyper-volume improvement acquisition function. In sequential batches of custom media experiments designed using our Bayesian criteria, collected using multiple assays targeting different cellular growth dynamics, the algorithm learned to identify the trade-off relationship between long-term growth and cost. We were able to identify several media with >100% more growth of C2C12 cells than the control, as well as a medium with 23% more growth at only 62.5% of the cost of the control. These algorithmically generated media also maintained growth far past the study period, indicating the modeling approach approximates the cell growth well from an extremely limited data set.

4.
Immunogenetics ; 75(4): 369-383, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37322230

RESUMEN

Though binding sites for the complement factor C1q and the canonical fragment crystallizable (Fc) gamma receptors (Fc[Formula: see text]Rs) on immunoglobulin G (IgG) molecules overlap, how C1q decoration of immune complexes (ICs) influences their ability to engage Fc[Formula: see text]Rs remains unknown. In this report, we use recombinant human Fc multimers as stable IC mimics to show that C1q engagement of ICs directly and transiently inhibits their interactions with Fc[Formula: see text]RIII (CD16) on human natural killer (NK) cells. This inhibition occurs by C1q engagement alone as well as in concert with other serum factors. Furthermore, the inhibition of Fc[Formula: see text]RIII engagement mediated by avid binding of C1q to ICs is directly associated with IC size and dependent on the concentrations of both C1q and Fc multimers present. Functionally, C1q-mediated Fc blockade limits the ability of NK cells to induce the upregulation of the cosignaling molecule, 4-1BB (CD137), and to mediate antibody-dependent cell-mediated cytotoxicity (ADCC). Although C1q is traditionally viewed as a soluble effector molecule, we demonstrate that C1q may also take on the role of an "immunologic rheostat," buffering Fc[Formula: see text]R-mediated activation of immune cells by circulating ICs. These data define a novel role for C1q as a regulator of immune homeostasis and add to our growing understanding that complement factors mediate pleiotropic effects.


Asunto(s)
Complemento C1q , Receptores de IgG , Humanos , Complemento C1q/metabolismo , Inmunoglobulina G , Citotoxicidad Celular Dependiente de Anticuerpos , Células Asesinas Naturales
5.
Biotechnol Bioeng ; 120(4): 1055-1067, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36581609

RESUMEN

Increases in global meat demands cannot be sustainably met with current methods of livestock farming, which has a substantial impact on greenhouse gas emissions, land use, water consumption, and farm animal welfare. Cultivated meat is a rapidly advancing technology that produces meat products by proliferating and differentiating animal stem cells in large bioreactors, avoiding conventional live-animal farming. While many companies are working in this area, there is a lack of existing infrastructure and experience at commercial scale, resulting in many technical bottlenecks such as scale-up of cell culture and media availability and costs. In this study, we evaluate theoretical cultivated beef production facilities with the goal of envisioning an industry with multiple facilities to produce in total 100,000,000 kg of cultured beef per year or ~0.14% of the annual global beef production. Using the computer-aided process design software, SuperPro Designer®, facilities are modeled to create a comprehensive analysis to highlight improvements that can lower the cost of such a production system and allow cultivated meat products to be competitive. Three facility scenarios are presented with different sized production reactors; ~42,000 L stirred tank bioreactor (STR) with a base case cost of goods sold (COGS) of $35/kg, ~211,000 L STR with a COGS of $25/kg, and ~262,000 L airlift reactor (ALR) with a COGS of $17/kg. This study outlines how advances in scaled up bioreactors, alternative bioreactor designs, and decreased media costs are necessary for commercialization of cultured meat products.


Asunto(s)
Reactores Biológicos , Carne , Animales , Bovinos , Técnicas de Cultivo de Célula/métodos
6.
Foods ; 11(19)2022 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-36230217

RESUMEN

The growth and activity of adherent cells can be enabled or enhanced through attachment to a solid surface. For food and beverage production processes, these solid supports should be food-grade, low-cost, and biocompatible with the cell of interest. Solid supports that are edible can be a part of the final product, thus simplifying downstream operations in the production of fermented beverages and lab grown meat. We provide proof of concept that edible filamentous fungal pellets can function as a solid support by assessing the attachment and growth of two model cell types: yeast, and myoblast cells. The filamentous fungus Aspergillus oryzae was cultured to produce pellets with 0.9 mm diameter. These fugal pellets were inactivated by heat or chemical methods and characterized physicochemically. Chemically inactivated pellets had the lowest dry mass and were the most hydrophobic. Scanning electron microscope images showed that both yeast and myoblast cells naturally adhered to the fungal pellets. Over 48 h of incubation, immobilized yeast increased five-fold on active pellets and six-fold on heat-inactivated pellets. Myoblast cells proliferated best on heat-treated pellets, where viable cell activity increased almost two-fold, whereas on chemically inactivated pellets myoblasts did not increase in the cell mass. These results support the use of filamentous fungi as a novel cell immobilization biomaterial for food technology applications.

7.
NPJ Sci Food ; 6(1): 46, 2022 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-36175443

RESUMEN

Cell culture media design is perhaps the most significant hurdle currently facing the commercialization of cultivated meat as an alternative source of dietary protein. Since media optimization for a specific culture system requires a significant amount of effort and investment, a major question remaining is whether media formulations can be easily shared across multiple production schemes for cells of different species and lineages. Here, we perform spent medium analysis to compare the specific nutrient utilization of primary embryonic chicken muscle precursor cells and fibroblasts to the murine C2C12 myoblast cell line. We demonstrate that these related cell types have significantly different nutrient utilization patterns collectively and on a per-cell basis, and that many components of conventional media do not appear to be depleted by the cells. Namely, glucose was not consumed as rapidly nor as completely by the chicken muscle precursors compared to other cells overall, and there were significant differences in specific consumption rates for several other key nutrients over the first day of culture. Ultimately, our results indicate that no one medium is likely ideal and cost effective to culture multiple cell types and that novel methods to streamline media optimization efforts will be important for the industry to develop.

8.
Pathog Immun ; 7(1): 104-121, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36072571

RESUMEN

Background: The continued emergence of SARS-CoV-2 variants has caused concern that a constantly evolving virus will escape vaccines and antibody therapies. New approaches are needed. Methods: We created and manufactured an ACE2 extracellular domain (ECD) fragment Fc fusion drug candidate, G921, and engineered the compound for enhanced delivery of drug to peripheral tissues by minimizing the size of the ACE2 ECD and by incorporating an Fc domain to enhance transcytosis. G921 was assessed for binding, neutralization, in vivo anti-inflammatory effect, and pharmacokinetic profile. Results: G921 was expressed as an IgG4 Fc fusion protein presenting two ACE2 domains to ACE2 ligands while avoiding risk of infection via antibody-dependent enhancement. G921 strongly binds to the SARS-CoV-2 Wuhan-Hu-1 spike protein and demonstrates further diminished off rate to the spike protein from each of the currently identified variants of concern. G921 demonstrates ACE2 enzymatic activity comparable to positive control and binding to the neonatal Fc receptor (FcRn) without binding to low affinity Fc-gamma receptors (FcγRs). G921 is effective in a concentration-dependent manner in a focus reduction neutralization assay with EC50=16.3±4.2 µg/mL without cytotoxicity in Vero E6 cells when tested at 200 µg/mL in an MTS cell proliferation assay. G921 demonstrates statistically significant reduction of lung inflammation in relevant models of both SARS-CoV-2 and influenza. The pharmacokinetic profile demonstrated dose-dependent exposure with a multi-day half-life in monkeys and rats. Conclusion: G921 data are consistent with both antiviral and anti-inflammatory modes of action. G921 is a novel approach for the prevention and treatment of COVID-19 and possible other diseases characterized by deficiency of ACE2.

9.
Biotechnol Bioeng ; 119(9): 2447-2458, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35538846

RESUMEN

Culture media used in industrial bioprocessing and the emerging field of cellular agriculture is difficult to optimize due to the lack of rigorous mathematical models of cell growth and culture conditions, as well as the complexity of the design space. Rapid growth assays are inaccurate yet convenient, while robust measures of cell number can be time-consuming to the point of limiting experimentation. In this study, we optimized a cell culture media with 14 components using a multi-information source Bayesian optimization algorithm that locates optimal media conditions based on an iterative refinement of an uncertainty-weighted desirability function. As a model system, we utilized murine C2C12 cells, using AlamarBlue, LIVE stain, and trypan blue exclusion cell counting assays to determine cell number. Using this experimental optimization algorithm, we were able to design media with 181% more cells than a common commercial variant with a similar economic cost, while doing so in 38% fewer experiments than an efficient design-of-experiments method. The optimal medium generalized well to long-term growth up to four passages of C2C12 cells, indicating the multi-information source assay improved measurement robustness relative to rapid growth assays alone.


Asunto(s)
Algoritmos , Modelos Biológicos , Agricultura , Animales , Teorema de Bayes , Medios de Cultivo , Ratones
10.
Microb Cell Fact ; 20(1): 204, 2021 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-34674718

RESUMEN

BACKGROUND: Metabolomics coupled with genome-scale metabolic modeling approaches have been employed recently to quantitatively analyze the physiological states of various organisms, including Saccharomyces cerevisiae. Although yeast physiology in laboratory strains is well-studied, the metabolic states under industrially relevant scenarios such as winemaking are still not sufficiently understood, especially as there is considerable variation in metabolism between commercial strains. To study the potential causes of strain-dependent variation in the production of volatile compounds during enological conditions, random flux sampling and statistical methods were used, along with experimental extracellular metabolite flux data to characterize the differences in predicted intracellular metabolic states between strains. RESULTS: It was observed that four selected commercial wine yeast strains (Elixir, Opale, R2, and Uvaferm) produced variable amounts of key volatile organic compounds (VOCs). Principal component analysis was performed on extracellular metabolite data from the strains at three time points of cell cultivation (24, 58, and 144 h). Separation of the strains was observed at all three time points. Furthermore, Uvaferm at 24 h, for instance, was most associated with propanol and ethyl hexanoate. R2 was found to be associated with ethyl acetate and Opale could be associated with isobutanol while Elixir was most associated with phenylethanol and phenylethyl acetate. Constraint-based modeling (CBM) was employed using the latest genome-scale metabolic model of yeast (Yeast8) and random flux sampling was performed with experimentally derived fluxes at various stages of growth as constraints for the model. The flux sampling simulations allowed us to characterize intracellular metabolic flux states and illustrate the key parts of metabolism that likely determine the observed strain differences. Flux sampling determined that Uvaferm and Elixir are similar while R2 and Opale exhibited the highest degree of differences in the Ehrlich pathway and carbon metabolism, thereby causing strain-specific variation in VOC production. The model predictions also established the top 20 fluxes that relate to phenotypic strain variation (e.g. at 24 h). These fluxes indicated that Opale had a higher median flux for pyruvate decarboxylase reactions compared with the other strains. Conversely, R2 which was lower in all VOCs, had higher median fluxes going toward central metabolism. For Elixir and Uvaferm, the differences in metabolism were most evident in fluxes pertaining to transaminase and hexokinase associated reactions. The applied analysis of metabolic divergence unveiled strain-specific differences in yeast metabolism linked to fusel alcohol and ester production. CONCLUSIONS: Overall, this approach proved useful in elucidating key reactions in amino acid, carbon, and glycerophospholipid metabolism which suggest genetic divergence in activity in metabolic subsystems among these wine strains related to the observed differences in VOC formation. The findings in this study could steer more focused research endeavors in developing or selecting optimal aroma-producing yeast stains for winemaking and other types of alcoholic fermentations.


Asunto(s)
Análisis de Flujos Metabólicos/métodos , Metaboloma , Modelos Biológicos , Saccharomyces cerevisiae/metabolismo , Compuestos Orgánicos Volátiles/metabolismo , Vino/microbiología , Fermentación , Microbiología de Alimentos , Metabolómica/métodos , Odorantes/análisis , Saccharomyces cerevisiae/genética , Compuestos Orgánicos Volátiles/análisis , Vino/análisis
11.
Biotechnol J ; 16(11): e2100228, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34387397

RESUMEN

Optimizing media for biological processes, such as those used in tissue engineering and cultivated meat production, is difficult due to the extensive experimentation required, number of media components, nonlinear and interactive responses, and the number of conflicting design objectives. Here we demonstrate the capacity of a nonlinear design-of-experiments (DOE) method to predict optimal media conditions in fewer experiments than a traditional DOE. The approach is based on a hybridization of a coordinate search for local optimization with dynamically adjusted search spaces and a global search method utilizing a truncated genetic algorithm using radial basis functions to store and model prior knowledge. Using this method, we were able to reduce the cost of muscle cell proliferation media while maintaining cell growth 48 h after seeding using 30 common components of typical commercial growth medium in fewer experiments than a traditional DOE (70 vs. 103). While we clearly demonstrated that the experimental optimization algorithm significantly outperforms conventional DOE, due to the choice of a 48 h growth assay weighted by medium cost as an objective function, these findings were limited to performance at a single passage, and did not generalize to growth over multiple passages. This underscores the importance of choosing objective functions that align well with process goals.


Asunto(s)
Algoritmos , Proyectos de Investigación , Técnicas de Cultivo de Célula , Medios de Cultivo , Músculos
12.
Microbiol Spectr ; 9(1): e0048521, 2021 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-34287034

RESUMEN

Genetic background and environmental conditions affect the production of sensory impact compounds by Saccharomyces cerevisiae. The relative importance of the strain-specific metabolic capabilities for the production of volatile organic compounds (VOCs) remains unclear. We investigated which amino acids contribute to VOC production and whether amino acid-VOC relations are conserved among yeast strains. Amino acid consumption and production of VOCs during grape juice fermentation was investigated using four commercial wine yeast strains: Elixir, Opale, R2, and Uvaferm. Principal component analysis of the VOC data demonstrated that Uvaferm correlated with ethyl acetate and ethyl hexanoate production, R2 negatively correlated with the acetate esters, and Opale positively correlated with fusel alcohols. Biomass formation was similar for all strains, pointing to metabolic differences in the utilization of nutrients to form VOCs. Partial least-squares linear regression showed that total aroma production is a function of nitrogen utilization (R2 = 0.87). We found that glycine, tyrosine, leucine, and lysine utilization were positively correlated with fusel alcohols and acetate esters. Mechanistic modeling of the yeast metabolic network via parsimonious flux balance analysis and flux enrichment analysis revealed enzymes with crucial roles, such as transaminases and decarboxylases. Our work provides insights in VOC production in wine yeasts. IMPORTANCE Saccharomyces cerevisiae is widely used in grape juice fermentation to produce wines. Along with the genetic background, the nitrogen in the environment in which S. cerevisiae grows impacts its regulation of metabolism. Also, commercial S. cerevisiae strains exhibit immense diversity in their formation of aromas, and a desirable aroma bouquet is an essential characteristic for wines. Since nitrogen affects aroma formation in wines, it is essential to know the extent of this connection and how it leads to strain-dependent aroma profiles in wines. We evaluated the differences in the production of key aroma compounds among four commercial wine strains. Moreover, we analyzed the role of nitrogen utilization on the formation of various aroma compounds. This work illustrates the unique aroma-producing differences among industrial yeast strains and suggests more intricate, nitrogen-associated routes influencing those aroma-producing differences.


Asunto(s)
Saccharomyces cerevisiae/metabolismo , Compuestos Orgánicos Volátiles/metabolismo , Vino/microbiología , Aminoácidos/metabolismo , Fermentación , Frutas/química , Frutas/metabolismo , Frutas/microbiología , Redes y Vías Metabólicas , Nitrógeno/metabolismo , Odorantes/análisis , Compuestos Orgánicos Volátiles/química , Vino/análisis
13.
Compr Rev Food Sci Food Saf ; 20(1): 686-709, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33325139

RESUMEN

Innovation in cultivated meat development has been rapidly accelerating in recent years because it holds the potential to help attenuate issues facing production of dietary protein for a growing world population. There are technical obstacles still hindering large-scale commercialization of cultivated meat, of which many are related to the media that are used to culture the muscle, fat, and connective tissue cells. While animal cell culture media has been used and refined for roughly a century, it has not been specifically designed with the requirements of cultivated meat in mind. Perhaps the most common industrial use of animal cell culture is currently the production of therapeutic monoclonal antibodies, which sell for orders of magnitude more than meat. Successful production of cultivated meat requires media that is food grade with minimal cost, can regulate large-scale cell proliferation and differentiation, has acceptable sensory qualities, and is animal ingredient-free. Much insight into strategies for achieving media formulations with these qualities can be obtained from knowledge of conventional culture media applications and from the metabolic pathways involved in myogenesis and protein synthesis. In addition, application of principles used to optimize media for large-scale microbial fermentation processes producing lower value commodity chemicals and food ingredients can also be instructive. As such, the present review shall provide an overview of the current understanding of cell culture media as it relates to cultivated meat.


Asunto(s)
Técnicas de Cultivo de Célula , Carne , Animales , Análisis Costo-Beneficio , Medios de Cultivo , Fermentación , Carne/análisis
14.
Front Microbiol ; 11: 2011, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32983023

RESUMEN

Establishment of the [GAR +] prion in Saccharomyces cerevisiae reduces both transcriptional expression of the HXT3 hexose transporter gene and fermentation capacity in high sugar conditions. We evaluated the impact of deletion of the HXT3 gene on the expression of [GAR +] prion phenotype in a vineyard isolate, UCD932, and found that changes in fermentation capacity were observable even with complete loss of the Hxt3 transporter, suggesting other cellular functions affecting fermentation rate may be impacted in [GAR +] strains. In a comparison of isogenic [GAR +] and [gar -] strains, localization of the Pma1 plasma membrane ATPase showed differences in distribution within the membrane. In addition, plasma membrane lipid composition varied between the two cell types. Oxygen uptake was decreased in prion induced cells suggesting membrane changes affect plasma membrane functionality beyond glucose transport. Thus, multiple cell surface properties are altered upon induction of the [GAR +] prion in addition to changes in expression of the HXT3 gene. We propose a model wherein [GAR +] prion establishment within a yeast population is associated with modulation of plasma membrane functionality, fermentation capacity, niche dominance, and cell physiology to facilitate growth and mitigate cytotoxicity under certain environmental conditions. Down-regulation of expression of the HXT3 hexose transporter gene is only one component of a suite of physiological differences. Our data show the [GAR +] prion state is accompanied by multiple changes in the yeast cell surface that prioritize population survivability over maximizing metabolic capacity and enable progeny to establish an alternative adaptive state while maintaining reversibility.

15.
Molecules ; 25(18)2020 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-32927698

RESUMEN

The quantitative and qualitative impacts of anthocyanins on proanthocyanidin adsorption to grape-derived cell wall material were investigated in fifteen unique systems of varying temperatures, ethanol concentrations, and proanthocyanidin concentrations. Proanthocyanidin solutions were exposed to cell wall material and monitored for changes in concentration over 24 h. Increases in both temperature and ethanol resulted in a larger retention of proanthocyanidins in solution and typically faster adsorption kinetics. Analysis of the solution after exposure to cell wall revealed a significant reduction in the molecular weight of proanthocyanidins present in solution, suggesting that anthocyanins do not alter a previously described mechanism of preferentially binding large molecular weight molecules. Additionally, a reduction in polymeric pigment abundance was noted in most conditions, suggesting rapid formation of polymeric pigment in the model solution and preferential adsorption of the polymeric pigment to cell wall material. Compared to a previous study of proanthocyanidin adsorption in the absence of anthocyanins, a significantly larger percentage of proanthocyanidin material was lost via adsorption-up to 70% of available material. In a winemaking context, this may suggest a preferential loss of polymeric pigment via adsorption to cap cell wall material compared to non-pigmented proanthocyanidins and free anthocyanins.


Asunto(s)
Antocianinas/farmacología , Pared Celular/efectos de los fármacos , Pared Celular/metabolismo , Etanol/farmacología , Proantocianidinas/metabolismo , Temperatura , Vitis/metabolismo , Adsorción , Antocianinas/química , Pared Celular/química , Etanol/química , Frutas/química , Cinética , Peso Molecular , Pigmentos Biológicos , Proantocianidinas/química , Vitis/química , Vino/análisis
16.
Biotechnol Bioeng ; 117(1): 109-116, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31544954

RESUMEN

Red wine production begins with a simultaneous fermentation and solid-phase extraction process. Red wine color and mouthfeel is the result of the extraction of phenolics from grape skins and seeds during fermentation, where extraction is a strong function of temperature and ethanol concentration. During fermentation, grape solids form a porous "cap" at the top of the fermentor, resulting in a heterogeneous fermentation system with significant temperature and concentration gradients. In this work, we present a spatial, time-variant reactor engineering model for phenolic extraction during red wine fermentation, incorporating fermentation kinetics, mass transfer, heat transfer, compressible fluid flow, and phenolic extraction kinetics. The temperature and ethanol concentration profiles predicted by this model allow for the calculation of phenolic extraction rates over the course of fermentation. Phenolic extraction predictions were validated against prior experimental data to good agreement and compared to a well-mixed model's predictions to show the utility of a spatial model over well-mixed models.


Asunto(s)
Ingeniería Química/métodos , Modelos Químicos , Fenoles/aislamiento & purificación , Vitis/química , Vino/análisis , Fermentación/fisiología , Fenoles/química
17.
Molecules ; 24(19)2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31581447

RESUMEN

Desorption of proanthocyanidins (PA) from grape cell wall material (CWM) was investigated in solutions of varying ethanol concentrations and increasing temperature. The results reveal the reversibility of PA-CWM interactions and the role that temperature and ethanol concentration play in the extent of PA desorption. Sequentially raising temperature from 15 to 35 °C resulted in desorption of up to 48% of the initial adsorbed PA. A comparison to a phenolic extraction model showed significant differences between the predicted and actual amount of PA that desorbed from the CWM. This suggests that the initial conditions of temperature and ethanol concentration must be considered when estimating PA extraction in red wine production. Under typical winemaking conditions, a significant amount of PA may be irreversibly adsorbed if exposed to CWM at low temperature (i.e., cold soak). A compositional analysis suggests the selective desorption of large molecular weight PA from CWM under all experimental conditions. Additionally, a preferential desorption of skin-derived PA over seed-derived PA was noted in the absence of ethanol.


Asunto(s)
Pared Celular/química , Proantocianidinas/química , Vino/análisis , Etanol/química , Calor , Peso Molecular , Vitis/química
18.
Molecules ; 24(18)2019 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-31540067

RESUMEN

The effects of temperature and ethanol concentration on the kinetics of anthocyanin adsorption and desorption interactions with five cell wall materials (CWM) of different composition were investigated. Using temperatures of 15 °C and 30 °C and model wine with ethanol concentrations of 0% and 15% (v/v) over 120 min, the adsorption and desorption rates of five anthocyanin-glucosides were recorded in triplicate. Small-scale experiments were conducted using a benchtop incubator to mimic a single berry fermentation. Results indicate that more than 90% of the adsorption occurs within the first 60 min of the addition of anthocyanins to CWM. However, desorption appears to occur much faster, with maximum desorption being reached after 30 min. The extent of both adsorption and desorption was clearly dependent not only on temperature and ethanol concentration but also on the CWM composition.


Asunto(s)
Antocianinas/química , Pared Celular/química , Etanol/química , Frutas/química , Calor , Vitis/química , Glucósidos/química
19.
Molecules ; 24(7)2019 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-30986909

RESUMEN

Phenolic extraction is a critical part of red wine making. Though empirical models of phenolic extraction kinetics exist, the current level of mechanistic understanding does not allow for accurate predictions. In this work, we propose a mechanistic model for the extraction of phenolics from grape skins and seeds as a function of temperature and ethanol. This model examines the release of phenolics, the adsorption of phenolics onto grape material, and the disappearance of anthocyanins from solution. Additionally, we performed epifluorescence microscopy to explore our finding that seed tannins' release rate appears independent of concentration, and found that the grape seed appears to ablate over fermentation. We also determined the activation energy of anthocyanin disappearance, in good agreement with similar systems. The proposed model results in an excellent fit, and increases the understanding of phenolic extraction and the ability to predict and optimize product outcome in red wine making.


Asunto(s)
Fenoles/química , Vitis/química , Vino , Etanol/química , Fermentación/fisiología , Semillas/química , Temperatura
20.
JCI Insight ; 4(2)2019 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-30674715

RESUMEN

The antiinflammatory effects of i.v. Ig (IVIG) in the treatment of autoimmune disease are due, in part, to the Fc fragments of Ig aggregates. In order to capitalize on the known antiinflammatory and tolerogenic properties of Ig Fc aggregates, we created a recombinant human IgG1 Fc multimer, GL-2045. In vitro, GL-2045 demonstrated high-avidity binding to Fc receptors, blocked the binding of circulating immune complexes from patients with rheumatoid arthritis to human Fcγ receptors (FcγRs), and inhibited antibody-mediated phagocytosis at log order-lower concentrations than IVIG. In vivo, administration of GL-2045 conferred partial protection against antibody-mediated platelet loss in a murine immune thrombocytopenic purpura (ITP) model. GL-2045 also suppressed disease activity in a therapeutic model of murine collagen-induced arthritis (CIA), which was associated with reduced circulating levels of IL-6. Furthermore, GL-2045 administration to nonhuman primates (NHPs) transiently increased systemic levels of the antiinflammatory cytokines IL-10 and IL-1RA, reduced the proinflammatory cytokine IL-8, and decreased surface expression of CD14 and HLA-DR on monocytes. These findings demonstrate the immunomodulatory properties of GL-2045 and suggest that it has potential as a treatment for autoimmune and inflammatory diseases, as a recombinant alternative to IVIG.

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