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 Dairy and Functional Foods Research: Wyndmoor, PA
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ARS Home Northeast Area Wyndmoor, Pennsylvania Eastern Regional Research Center Dairy and Functional Foods Research People & Locations







Karley K Mahalak
                        Dairy and Functional Foods Research

                        




                        
                        Research Molecular Biologist
                        Phone: (215) 836-6922
                        
                        
                        Fax: (Employee information on this page comes from the REE Directory. Please contact your front office staff to update the REE Directory.)
                            ProjectsIn vitro Human Gut System: Interactions Between Diet, Food Processing, and Microbiota
                                                    In-House Appropriated
                                                                    (D)Accession Number: 439225Fatty Acids Metabolism in the Gastrointestinal Tract Using In Vitro Enteroid Models Derived from Mice and Humans
                                                    Non-Assistance Cooperative Agreement
                                                                    (S)Accession Number: 437564**Publications**
                                                (Clicking on the reprint icon
                                                    Reprint Icon
                                                    will take you to the publication reprint.)Supplementation with soluble or insoluble rice-bran fibers increases short-chain fatty acid producing bacteria in the gut microbiota in vitro
                                                        

- (Peer Reviewed Journal)Mahalak, K.K., Liu, L.S., Bobokalonov, J., Narrowe, A.B., Firrman, J., Bittinger, K., Hu, W., Jones, S.M., Mustafa, A.M. 2024. Supplementation with soluble or insoluble rice-bran fibers increases short-chain fatty acid producing bacteria in the gut microbiota in vitro. Frontiers in Nutrition. https://doi.org/10.3389/fnut.2024.1304045.Targeted remodeling of the human gut microbiome using Juemingzi (Senna seed extracts)
                                                        

- (Peer Reviewed Journal)Narrowe, A.B., Scarino Lemons, J.M., Mahalak, K.K., Firrman, J., Van Den Abbeele, P., Baudot, A., Deyaert, S., Li, Y., Yu, L., Liu, L.S. 2024. Targeted remodeling of the human gut microbiome using Juemingzi (Senna seed extracts). Frontiers in Cellular and Infection Microbiology. 14.  https://doi.org/10.3389/fcimb.2024.1296619.Metagenomes and metagenome-assembled genomes from ex vivo fecal incubations of six unique donors
                                                        

- (Peer Reviewed Journal)Narrowe, A.B., Liu, L.S., Scarino Lemons, J.M., Firrman, J., Mahalak, K.K., Deyaert, S., Baudot, A., Van Den Abbeele, P. 2024. Metagenomes and metagenome-assembled genomes from ex vivo fecal incubations of six unique donors. Microbiology Resource Announcements. https://doi.org/10.1128/mra.00862-23.Transcriptomic analysis on the regulation of tomato ripening by carbon dioxide
                                                        

- (Peer Reviewed Journal)Bobokalonov, J., Liu, Y., Mahalak, K.K., Firrman, J., Sheen, S., Zhou, S., Liu, L.S. 2023. Transcriptomic analysis on the regulation of tomato ripening by carbon dioxide. Sci. 5(3):26. https://doi.org/10.3390/sci5030026.Lacticaseibacillus rhamnosus strain GG (LGG) regulate gut microbial metabolites, an in vitro study using three mature human gut microbial cultures in a simulator of human intestinal microbial ecosystem (SHIME)
                                                        

- (Peer Reviewed Journal)Liu, L.S., Narrowe, A.B., Firrman, J., Mahalak, K.K., Bobokalonov, J., Scarino Lemons, J.M., Bittinger, K., Daniel, S., Tanes, C., Mattei, L., Friendman, E., Soares, J.W., Masuko, K., Zeng, W., Tomasula, M.M. 2023. Lacticaseibacillus rhamnosus strain GG (LGG) regulate gut microbial metabolites, an in vitro study using three mature human gut microbial cultures in a simulator of human intestinal microbial ecosystem (SHIME). Foods. https://doi.org/10.3390/foods12112105.An in-vitro analysis of how lactose modifies the gut microbiota structure and function of adults in a donor-independent manner
                                                        

- (Peer Reviewed Journal)Firrman, J., Liu, L.S., Mahalak, K.K., Hu, W., Bittinger, K., Moustafa, A., Jones, S.M., Narrowe, A.B., Tomasula, M.M. 2023. An in-vitro analysis of how lactose modifies the gut microbiota structure and function of adults in a donor-independent manner. Frontiers in Nutrition. https://doi.org/10.3389/fnut.2022.1040744.Fructooligosaccharides (FOS) differentially modifies the in vitro gut microbiota in an age-dependent manner.
                                                        

- (Peer Reviewed Journal)Mahalak, K.K., Firrman, J., Narrowe, A.B., Hu, W., Bittinger, K., Moustafa, A., Liu, L.S. 2023. Fructooligosaccharides (FOS) differentially modifies the in vitro gut microbiota in an age-dependent manner. Frontiers in Nutrition. https://doi.org/10.3389/fnut.2022.1058910.Modulation of the Gut Microbiota Structure and Function by Two Structurally Different Lemon Pectins
                                                        

- (Peer Reviewed Journal)Firrman, J., Mahalak, K.K., Bobokalonov, J., Liu, L.S., Lee, J., Bittinger, K., Mattei, L., Gadaingan, R.T., Narrowe, A.B., Scarino Lemons, J.M. 2022. Modulation of the Gut Microbiota Structure and Function by Two Structurally Different Lemon Pectins. Foods. https://doi.org/10.3390/foods11233877.Persistence of the probiotic Lacticaseibacillus rhamnosus strain GG (LGG) in an in vitro model of the gut microbiome
                                                        

- (Peer Reviewed Journal)Mahalak, K.K., Firrman, J., Bobokalonov, J., Narrowe, A.B., Bittinger, K., Daniel, S., Tanes, C., Mattei, L., Zeng, W., Soares, J.W., Kobori, M., Scarino Lemons, J.M., Tomasula, M.M., Liu, L.S. 2022. Persistence of the probiotic Lacticaseibacillus rhamnosus strain GG (LGG) in an in vitro model of the gut microbiome. International Journal of Molecular Sciences. https://doi.org/10.3390/ijms232112973.The impact of environmental pH on the gut microbiota community structure and short chain fatty acid production
                                                        

- (Peer Reviewed Journal)Firrman, J., Liu, L.S., Mahalak, K.K., Tu, V., Tanes, C., Bittinger, K., Bobokalonov, J., Mattei, L., Zhang, H., Van Den Abeele, P. 2022. The impact of environmental pH on the gut microbiota community structure and short chain fatty acid production. FEMS Microbiology Ecology. 98(5). https://doi.org/10.1093/femsec/fiac038.Analysis of the ability of capsaicin to modulate the human gut microbiota in vitro
                                                        

- (Peer Reviewed Journal)Mahalak, K.K., Bobokalonov, J., Firrman, J., Williams, R., Evans, B., Fanelli, B., Soares, J., Liu, L.S., Kobori, M. 2022. Analysis of the ability of capsaicin to modulate the human gut microbiota in vitro. Nutrients. https://doi.org/10.3390/nu14061283.Changes to environmental pH alters the colon microbial community in terms of both structure and function: An in vitro analysis

- (Abstract Only)Environmental pH is a determinant of the gut microbiota community composition and production of short chain fatty acids

- (Abstract Only)Comparative analysis of the gut microbiota cultured in vitro using a single colon versus a 3-stage colon experimental design
                                                        

- (Peer Reviewed Journal)Firrman, J., Liu, L.S., Mahalak, K.K., Tanes, C., Bittinger, K., Bobokalonov, J., Van Den Abbeele, P., Mattei, L., Zhang, H. 2021. Comparative analysis of the gut microbiota cultured in vitro using a single colon versus a 3-stage colon experimental design. Applied Microbiology and Biotechnology. volume 105, pages 3353–3367. https://link.springer.com/article/10.1007/s00253-021-11241-x.Triclosan has a robust, yet reversible impact on human gut microbial composition in vitro.
                                                        

- (Peer Reviewed Journal)Mahalak, K.K., Firrman, J., Lee, J., Bittinger, K., Nunez, A., Bobokalonov, J., Arango-Argoty, G., Zhang, L., Zhang, G., Liu, L.S. 2020. Triclosan has a robust, yet reversible impact on human gut microbial composition in vitro. PLoS One. 15(6): 1-22. https://doi.org/10.1371/journal.pone.0234046.Impact of steviol glycosides and erythritol on the human and Cebus apella gut microbiome
                                                        

- (Peer Reviewed Journal)Mahalak, K.K., Firrman, J., Tomasula, M.M., Nunez, A., Lee, J., Bittinger, K., Rinaldi, W., Liu, L.S. 2019. Impact of steviol glycosides and erythritol on the human and Cebus apella gut microbiome. Journal of Agricultural and Food Chemistry. Pages A-I. https://doi.org/10.1021/acs.jafc.9b06181.Metagenomic assessment of the Cebus Apella gut microbiota
                                                        

- (Peer Reviewed Journal)Firrman, J., Tanes, C., Bittinger, K., Mahalak, K.K., Rinaldi, W., Liu, L.S. 2019. Metagenomic assessment of the Cebus Apella gut microbiota. American Journal of Primatology. https://doi.org/10.1002/ajp.23023.


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