Progress 01/01/24 to 12/31/24
Outputs
Target Audience:The target audiences for this research include academics and govt. researchers, students, nutrition and health companies, and food companies. The research results were submitted topeer-reviewed journals and presented to stakeholders represented above through conference presentations. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?The project supported the training of one postdoctoral scholar and one assistant project scientist. How have the results been disseminated to communities of interest?The results in this period were predominantly disseminated through peer-reviewed publications and presentations to stakeholders such as Natural product expo and other events focused on food industries. What do you plan to do during the next reporting period to accomplish the goals?The next stage plans are to evaluate 1. Developed computational and bioanalytical approaches to characterize the metabolism of polyphenols in probiotic and commensal bacteria 2. Understand the metabolism of polyphenols in diverse bacterial systems and their potential to reduce gut inflammation using combination of in-vitro and in-vivo models
Impacts
What was accomplished under these goals?
The first study have focused on survivability of probiotic cells is crucial for adhering to gut epithelial cells, modulating the microbiota, and exerting their health-promoting effects. This study focused on the vacuum infusion of a model plant extract catechin in live Lacticaseibacillus probiotic cells as an innovative strategy to enhance the persistence and colonization of viable probiotic cells in the gut. The metabolic activity and antagonistic effect against the pathogen of probiotic cells with and without infused catechin and after their treatment with simulated gastric fluid (SGF) were evaluated. A mouse model study was conducted to evaluate the persistence and colonization of the cells with and without infused catechin in the gut. Results showed that catechin-infused Lacticaseibacillus cells exhibited significantly enhanced viability, with only ~0.1 Log CFU/mL reduction in viability after simulated gastrointestinal digestion. The metabolic activity and antagonistic effect of cells infused with catechin remained unchanged compared tonon-infused cells. Furthermore, catechin-infused cells demonstrated improved survivability, extended persistence, and enhanced colonization in the mouse gut. This study highlights a novel probiotic-polyphenol formulation that promotes targeted delivery of probiotics to the gut while delivering beneficial plant phenolic metabolites, paving the way for improved functional food applications. Encapsulation within living microbial cells offers a dual advantage over conventional inert carriers by enabling both protection and metabolic transformation of bioactive compounds. This second study evaluated the potential of bacteria as a live biocatalytic carrier for the encapsulation and in situ biotransformation of curcumin--a model polyphenol with poor solubility and chemical instability. Curcumin was introduced into viable bacterial cells using vacuum-assisted infusion, a non-thermal, mild-pressure technique optimized for small, hydrophobic molecules. Post-loading assessments revealed that encapsulation resulted in a reduction of mitochondrial metabolic activity (34% in controls vs. 42% in curcumin-loaded cells) and a 39% decrease in viable cell count. However, partial recovery of metabolic function was observed within 2 h, indicating retained viability and functional resilience. Genome-wide analysis using CAMPER identified NADPH-dependent reductase genes, including curcumin reductase (CurA), supporting the strain's capacity for biotransformation. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) detected hydrogenated curcumin metabolites--dihydrocurcumin and tetrahydrocurcumin--confirming microbial conversion. Encapsulated cells exhibited a transient lag phase in growth kinetics (1.88 h) followed by adaptation, along with sustained curcumin retention (~31% after 9 h). Together, these results demonstrate that bacteria can serve as a viable, metabolically active carrier for polyphenol-based therapeutics, offering a foundation for the development of site-specific, stable, and bioactive formulations using live microbial systems.
Publications
- Type:
Conference Papers and Presentations
Status:
Submitted
Year Published:
2025
Citation:
Polyphenol-modified Probiotics for the Enhanced Survivability, Persistence and Colonization of Probiotic Cells in the Gut
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2025
Citation:
AI for food safety and quality
|
Progress 01/01/23 to 12/31/23
Outputs
Target Audience:The target audiences for this research include academics and govt. researchers, students, nutrition and health companies, and food companies. The research results werepublished in peer-reviewed journals and presented to stakeholders represented above through conference presentations. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?The project supported the training of a graduate student and a postdoctoral scholar who was also promoted to a project scientist in this period. The graduate student passed her QE exam to become a PhD candidate in our graduate program. How have the results been disseminated to communities of interest?The results in this period were predominantly disseminated through peer-reviewed publications and presentations to stakeholders during their visit to UC Davis for events such as the annual Research Day for the Food Science Department. What do you plan to do during the next reporting period to accomplish the goals?The next steps for us are to: 1) Validate the potential of diverse polyphenolic compounds to improve the stability and delivery of probiotics in-vitro and in-vivo. 2) Measure the metabolites generated by phenolic infused probiotics and gene expression changes in the probiotic cells
Impacts
What was accomplished under these goals?
This first part of the study was focused on developing novel compositions for the simultaneous delivery of probiotics and phenolic bioactives. These novel compositions were generated by biosorption of phenolic-rich plant extracts produced using jabuticaba peel, guaraná seed, and pure catechin in three probiotic strains using vacuum-assisted and passive incubations. Vacuum-assisted biosorption using jabuticaba peel in 25% of ethanol solution (JP25%) provided the maximum loading of phenolic compounds (PC), around 9 mg Gallic Acid Equivalent (GAE)/g of cells in less than 5 min without significantly influencing probiotic cell viability. In contrast, the total phenolic content of probiotic cells loaded with guaraná seed extract (GSE) and catechin solution ranged between 3.5 and 5 mg GAE/g of cells. The PC content of probiotic cells using vacuum-assisted biosorption was around 2-4 fold higher than that obtained via passive biosorption for 24 h. The biosorption of PCs in probiotic cells was also confirmed by multiphoton microscopy. The viability of freeze-dried cells at 25 °C up to 30 days loaded with plant extracts by vacuum assisted biosorption was 1-2 log CFU/g higher than cells passively loaded with plant extracts. Furthermore, PC release from Lacticaseibacillus cells ranged between 55% and 75% of biosorbed PCs during simulated gastrointestinal digestions. Overall, this study illustrates a novel approach to formulate combination of probiotics and PCs and their potential to deliver viable probiotics and bioactive PCs. In our second study, simultaneous in-vivo delivery of phenolic compounds (PC) and probiotics was evaluated to improve the proliferation of probiotics and the absorption of PC and their metabolites in the gut. This study focused on the vacuum infusion of a model plant extract catechin in live probiotic cells as an alternative to improve the viability of probiotics during simulated gastrointestinal digestion. The metabolic activity and antagonistic effect against the pathogen of probiotic cells with and without infused catechin and after their treatment with simulated gastric fluid (SGF) were evaluated. A mouse model study was conducted to evaluate the persistence and colonization of the cells with and without infused catechin in the gut. Vacuum infusion of catechin increased the viability of probiotic cells by ~ 2 log during in-vivo delivery. The metabolic activity and antagonistic effect of cells with infused catechin remained the same as those without infused catechin. The cells with infused catechin survived, persisted longer, and colonized in the gut of a mouse model. In summary, this study provides a novel approach to the targeted delivery of both probiotics and plant phenolics to the gut with enhanced colonization tendency of probiotic cells and delivery of beneficial plant phenolic metabolites.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2023
Citation:
Marluci Palazzolli da Silva, Rewa Rai, Carmen Silvia Favaro-Trindade, Nitin Nitin, Vacuum-assisted biosorption for developing combined delivery formulations of live probiotics and plant-phenolic compounds and their in-vitro evaluation, Food Bioscience, 54, 1-10, 2023,
- Type:
Journal Articles
Status:
Submitted
Year Published:
2024
Citation:
Improvement survivability, persistence, and colonization of probiotics in the gut by synergistic combination of polyphenols with probiotics
|
Progress 01/01/22 to 12/31/22
Outputs
Target Audience:The target audiences for this research include academics and govt. researchers, students, nutrition and health companies, and food companies. During this reporting period, the results of this research were shared with a broad range of audiences, including industry representatives,at the ACS meeting in March 2022. In addition, the research results were also published in peer-reviewed journals. Furthermore, the results of this research also resulted in the filing of a patent application. The marketing material associated with this patent application was shared with the leading food and nutritional health companies by the UC Davis office of Innovation Access. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?The grant supported the training of a postdoctoral fellow, recently promoted to an assistant project scientist at UC Davis and a second-year graduate student. How have the results been disseminated to communities of interest?The results were disseminated through presentation at national level conferences, peer reviewed publications, marketing material for the patent application to leading companies in food and health sector What do you plan to do during the next reporting period to accomplish the goals?The plan is to conduct: 1. In-vivo evaluation of the phenolic-probiotic formulations 2. Develop a mechanistic understanding of the role of phenolic compounds in enhancing the stability and persistence of probiotic formulations 3. Discover the diverse classes of phenolic compounds that enhance the probiotic survival and persistence
Impacts
What was accomplished under these goals?
In year 1 of the grant, we focused on characterizing the infusion of plant phenolics in diverse probiotic bacteria and assessing their role in improving the resistance of these bacteria to gastric and intestinal barriers. The key results are: (a) Characterizing grape phenolics in probiotic lactic acid bacteria: This part of the study develops an innovative cell-based carrier to encapsulate multiple phytochemicals from a complex plant source simultaneously. Muscadine grapes (MG) juice prepared from fresh fruit was used as a model juice. After incubation with inactivated bacterial cells, 66.97% of the total anthocyanins and 72.67% of the total antioxidant compounds were encapsulated in the cells from MG juice. Confocal images illustrated a uniform localization of the encapsulated material in the cells. The spectral emission scans indicated the presence of a diverse class of phenolic compounds, which was characterized using high-performance liquid chromatography (HPLC). Using HPLC, diverse phytochemical compound classes were analyzed, including flavanols, phenolic acid, hydroxycinnamic acid, flavonols, and polymeric polyphenols. The analysis validated that the cell carrier could encapsulate a complex profile of bioactive compounds from fruit juice, and the encapsulated content and efficiencies varied by chemical class and compound. In addition, after the heat treatment at 90 °C for 60 min, >87% total antioxidant capacity and 90% anthocyanin content were recovered from the encapsulated MG. In summary, these results highlight the significant potential of a selected bacterial strain for the simultaneous encapsulation of diverse phenolic compounds from fruit juice and for improving their process stability. (b)Role of plant phenolics in influencing stability of probiotics and the release of plant phenolics from probiotic cells during simulated digestion studies: This part of the study focused on developing novel compositions for the simultaneous delivery of probiotics and phenolic bioactives. These novel compositions were generated by biosorption of phenolic-rich plant extracts produced using jabuticaba peel, guaraná seed, and pure catechin in three probiotic strains using vacuum-assisted and passive incubations. Vacuum-assisted biosorption using jabuticaba peel in 25% of ethanol solution (JP25%) provided the maximum loading of phenolic compounds (PC), around 9 mg Gallic Acid Equivalent (GAE)/g of cells in less than 5 minutes without significantly influencing probiotic cell viability. In contrast, the total phenolic content of probiotic cells loaded with guaraná seed extract (GSE) and catechin solution ranged between 3.5 to 5 mg GAE/g of cells. The PC content of probiotic cells using vacuum-assisted biosorption was around 2-4 fold higher than that obtained via passive biosorption. The biosorption of PCs in probiotic cells was also confirmed by multiphoton microscopy.The viability of freeze-dried cells loaded with plant extracts by vacuum was between 8 to 10 log CFU/g stored at 25 °C up to 30 days. Furthermore, PC release from Lacticaseibacillus cells during simulated digestion was ~60% in the presence of simulated gastrointestinal digestion. This research provides a novel platform to deliver probiotics and PC in the gut.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2022
Citation:
Lactic Acid Bacteria Simultaneously Encapsulate Diverse Bioactive Compounds from a Fruit Extract and Enhance Thermal Stability
F Dou, R Rai, N Nitin, Molecules 27 (18), 5821
- Type:
Journal Articles
Status:
Submitted
Year Published:
2022
Citation:
Vacuum-assisted biosorption as a promising approach for simultaneous delivery of live probiotics and plant-phenolic compounds
Marluci Palazzolli da Silvaa,b, Rewa Raia, Carmen S. F�varo-Trindadeb, Nitin Nitin
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2022
Citation:
Improvement of probiotic survivability, persistence and colonization in the gut by loading probiotic cells with plant extracts, R. Rai and N. Nitin, ACS National Meeting, 2022
|
|