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Frost, S. C.

Publications and source records attributed to Frost, S. C..

6 recordsLinked to original sources

Impact of Adipogenic Differentiation on the Nutrition and Sensory Profile of Cultivated Pork Fat Tissue

Adipose tissue is a principal source of texture, flavor, and aroma in meat products. Higher fat content corresponds to higher juiciness, tenderness and overall palatability of meat products, making it a key component of cultivated meat. Our previous study investigated the aromatic characteristics of cultivated pork fat tissue, finding comparable consumer panel hedonic scores between conventional livestock derived and cultivated pork fats. Further research was pursued to characterize if adipogenic differentiation of the cells is required to enhance the flavor of cultivated fat. While differentiation of cultivated cells results in tissues that more closely resemble the morphology of livestock-derived tissue, the process substantially increases production timelines and material costs associated with cultivated meat production. As a result, we observed changes in organoleptic and nutritional properties of cultivated pork fat cells associated with differentiation of porcine dedifferentiated fat (PDFAT) cells. We assessed the effect of varying degrees of adipogenesis with soybean oil supplementation on fat content, composition, and volatile compound formation. Notably, we observed the concentrations of 2-pentylfuran, 2-heptanone, hexanal and (E)-2-octenal increased compared to the undifferentiated preadipocytes. These compounds, along with other ketones, aldehydes, alcohol and lactone molecules, contribute to fruity, herbal, and fatty aromas. Additionally, these results were achieved without requiring the maximum differentiation time frame of 12 days in culture. These findings emphasize the importance of adipocyte differentiation in cultivated fat production and highlight its potential as a strategy for optimizing both flavor and nutritional attributes of cultivated meat.

bioengineering↗

Modulation of Nutritional Composition and Aroma Volatiles in Cultivated Pork Fat by Culture Media Supplementation

Cultivated meat is emerging as a novel food source with the potential to contribute to a more sustainable and ethical food production system. However, limited research to date has explored the extent to which the nutrition and the aroma of such foods can be altered through cell culture conditions. Here, we aimed to modulate the aromatic volatile compounds in heated porcine cultivated fat cells by manipulating the media components while ensuring the preservation of robust fat differentiation. Using dynamic headspace gas chromatography-mass spectrometry (DHS-GC-MS), we demonstrated that supplementing cells with thiamine-HCl increased its intracellular concentration and promoted the production of 4-methyl-5-thiazoleethanol, contributing to milky aroma. Similarly, supplementation with L-methionine enhanced its intracellular concentration and increased the production of methional, a volatile compound with a potato-like aroma. Additionally, myoglobin significantly altered the volatile organic compound profile of cultivated fat. Notably, the concentration of {gamma}-nonalactone, (E,E)-2,4-decadienal and 2-pentylfuran were increased, which contribute to a coconut-like, deep fat, fruity aroma, respectively, as well as elevated levels of other alcohols, aldehydes and furans. These findings highlight the potential of culture media formulations to modulate the aroma in cultivated fat production, a unique opportunity to optimize sensory features using this novel food production technology. HighlightsNutrient composition and aroma profiles of cultivated pork fat upon baking were modulated by cell culture media supplementation. Supplementing with thiamine-HCl, L-methionine, or myoglobin increased intracellular levels of thiamine or methionine and modulated the formation of aroma volatiles, enhancing characteristic odors such as milky, potato-like, and coconut-like notes. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=106 SRC="FIGDIR/small/667495v1_ufig1.gif" ALT="Figure 1"> View larger version (15K): org.highwire.dtl.DTLVardef@11cd7c4org.highwire.dtl.DTLVardef@99b290org.highwire.dtl.DTLVardef@9a47beorg.highwire.dtl.DTLVardef@dc1689_HPS_FORMAT_FIGEXP M_FIG C_FIG Graphical overview of the methodology. Porcine dedifferentiated fat cells (pDFAT) were differentiated into adipocytes using adipogenesis media supplemented with aroma precursors. The cells were heated (cooked) and the resulting volatile compounds were analyzed using dynamic headspace gas chromatography-mass spectrometry (DHS-GC-MS).

biochemistry↗

Chemical and Sensory Analyses of Cultivated Pork Fat Tissue as a Flavor Enhancer for Meat Alternatives

The emerging field of cellular agriculture has accelerated the development of cell-cultivated adipose tissue as an additive to enhance the flavor of alternative meat products. However, there has been limited research to evaluate the sensory profile of in vitro-grown tissues compared to conventionally obtained animal fat. This study aimed to investigate the aromatic characteristics of cell-cultivated fat tissue as a flavor enhancer for meat alternatives. Porcine dedifferentiated fat cells were clonally isolated and differentiated into adipocytes. This cultured adipose tissue was then analyzed alongside native porcine fat using gas chromatography-mass spectrometry (GC/MS) coupled with descriptive sensory analysis by human panelists. This evaluation enabled quantitative and qualitative assessments of volatile compounds released during cooking for both in vitro and in vivo porcine fats. The volatile profiles generated during the cooking process and fatty aroma characteristics reported by sensory panelists were largely similar between the two fat sources, with some differences in the concentration of select compounds and aroma attributes. Ultimately, the panelists found comparable overall liking scores reported between the conventional and cultured porcine fats. These findings provide valuable sensory evidence supporting the viability of cell-cultivated adipose tissue as a flavor component of meat alternatives, substituting for conventional animal fat.

bioengineering↗

β-Caryophyllene Enhances the Transcriptional Upregulation of Cholesterol Biosynthesis in Breast Cancer Cells

{beta}-caryophyllene (BCP) exhibits anti-proliferative properties in cancer cells. Here, we examine the hypothesis that BCP induces membrane remodeling. Our data show that high concentrations of BCP increase membrane permeability of human breast cells (hBrC) causing detachment and cell death. At a sub-lethal concentration of BCP, we show that BCP induces a striking upregulation of genes involved in cholesterol biosynthesis, including the gene that encodes for HMGCoA reductase (HMGCR), the rate-determining step in cholesterol biosynthesis. In addition, stearoyl-CoA desaturase (SCD) is also upregulated which would lead to the enhanced formation of monounsaturated fatty acids, specifically oleate and palmitoleate from stearoyl CoA and palmitoyl CoA, respectively. These fatty acids are major components of membrane phospholipids and cholesterol esters. Together, these data suggest that cells respond to BCP by increasing the synthesis of components found in membranes. These responses could be viewed as a repair mechanism and/or as a mechanism to mount resistance to the cytotoxic effect of BCP. Blocking HMGCR activity enhances the cytotoxicity of BCP, suggesting that BCP may provide an additional therapeutic tool in controlling breast cancer cell growth.

cancer biology↗

A non-catalytic function of carbonic anhydrase IX contributes to the glycolytic phenotype and pH regulation in human breast cancer cells

The most aggressive and invasive tumor cells often reside in hypoxic microenvironments and rely heavily on rapid anaerobic glycolysis for energy production. This switch from oxidative phosphorylation to glycolysis, along with up-regulation of the glucose transport system, significantly increases the release of lactic acid from cells into the tumor microenvironment. Excess lactate and proton excretion exacerbate extracellular acidification to which cancer cells, but not normal cells, adapt. We have hypothesized that carbonic anhydrases (CAs) play a role in stabilizing both intracellular and extracellular pH to favor cancer progression and metastasis. Here we show that proton efflux (acidification) using the glycolytic rate assay is dependent on both extracellular pH (pHe) and CA IX expression. Yet, isoform selective sulfonamide-based inhibitors of CA IX did not alter proton flux, which suggests that the catalytic activity of CA IX is not necessary for this regulation. Other investigators have suggested the CA IX cooperates with the MCT transport family to excrete protons. To test this possibility, we examined the expression patterns of selected ion transporters and show that members of this family are differentially expressed within the molecular subtypes of breast cancer. The most aggressive form of breast cancer, triple negative breast cancer (TNBC), appears to coordinately express the monocarboxylate transporter 4 (MCT4) and carbonic anhydrase IX (CA IX). This supports a possible mechanism that utilizes the intramolecular H+ shuttle system in CA IX to facilitate proton efflux through MCT4.

cancer biology↗

Selective inhibition of CA IX over CA XII using benzene sulfonamides: Disconnect between CA activity and growth inhibition in breast cancer cells

Carbonic anhydrases (CAs) have been linked to tumor progression, particularly membrane-bound CA isoform IX (CA IX). The role of CA IX in the context of breast cancer is to regulate the pH of the tumor microenvironment. In contrast to CA IX, expression of CA XII, specifically in breast cancer, is associated with better outcome despite performing the same catalytic function. In this study, we have structurally modeled the orientation of bound ureido-substituted benzene sulfonamides (USBs) within the active site of CA XII, in comparison to CA IX and cytosolic off-target CA II, to understand isoform specific inhibition. This has identified specific residues within the CA active site, which differ between isoforms that are important for inhibitor binding and isoform specificity. The ability of these sulfonamides to block CA IX activity in breast cancer cells is less effective than their ability to block activity of the recombinant protein (by one to two orders of magnitude depending on the inhibitor). The same is true for CA XII activity but now they are two to three orders of magnitude less effective. Thus, there is significantly greater specificity for CA IX activity over CA XII. While the inhibitors block cell growth, without inducing cell death, this again occurs at two orders of magnitude above the Ki values for inhibition of CA IX and CA XII activity in their respective cell types. Surprisingly, the USBs inhibited cell growth even in cells where CA IX and CA XII expression was ablated. Despite the potential for these sulfonamides as chemotherapeutic agents, these data suggest that we reconsider the role of CA activity on growth potentiation.

cancer biology↗