Dr Restituto Tocmo
Building locationHarry Nursten
Areas of interest
My research interests are largely directed towards understanding how dietary bioactives and nutritional components (e.g., proteins) influence physiological systems, with a focus on the modulation of immune responses (innate and adaptive) and cellular antioxidant signaling pathways in the context of chronic intestinal inflammatory disease. My specific areas of interest are:
- Diet and immune function: My recent focus is to investigate how protein hydrolysates can influence intestinal barrier function and modulate immune response in macrophages and dendritic cells, as well as the differentiation of naive CD4 T cells into one of several lineages of T helper (Th) cells.
- Dietary bioactives and cellular antioxidant signaling: My work I this area aims to clarify the antioxidant mechanisms of food bioactives using cell culture techniques with a focus on how these boactives influence the Keap1-Nrf2 pathway and the Aryl hydrocarbon receptor (AhR).
- Food material modification through bioconversion: Extraction of plant proteins and their bioconversion into protein hydrolysates; evaluation of techno-functional properties.
- Isolation, purification, and identification of dietary bioactives: Analytical characterisation and semi-preparative isolation/purification of plant-derived natural products (e.g., organosulfur compounds, xanthones, polyphenolics) to investigate their anti-inflammatory and antioxidant properties.
Research centres and groups
- PhD Food Science, National University of Singapore, Singapore
- MSc Food Science, Cornell University, Ithaca, New York State
- BSc Food Technology, University of the Philippines
Ozcam, M, Oh, J-H, Tocmo, R, et al, Van Pijkeren. A secondary metabolite drives intraspecies antagonism in a gut symbiont that is inhibited by cell wall acetylation. Cell Host & Microbe, 2022, 30:824– 835.e6.
Vemu, B.; Tocmo, R.; et al., Johnson, J.J Pharmacokinetic characterization of carnosol from rosemary (Salvia Rosmarinus) in male C57BL/6 mice and inhibition profile in human cytochrome P450 enzymes. Toxicology and Applied Pharmacology 431 (2021) 115729.
Huang, Y., Tocmo, R., Nauman, M.C., Haughan, M., Johnson, J.J. Defining the cholesterol lowering mechanism of bergamot (Citrus bergamia) extract in HepG2 and Caco-2 cells. Nutrients, 2021, 13 (9), 3156.
Tocmo, R., Lee, B.Q., Heun, A., van Pijkeren, J.P., Parkin, K., Johnson, J.J. Prenylated xanthones from mangosteen (Garcinia mangostana) activate the AhR and Nrf2 pathways and protect intestinal barrier integrity in HT-29 cells. Free Radical Biology and Medicine, 2021, 163, 102–115.
Tocmo, R, Pena-Fronteras, J., Calumba, K.F., Mendoza, M. Johnson, J.J. (2020). Valorization of pomelo (Citrus grandis Osbeck) peel: A review of current utilization, phytochemistry, bioactivities and mechanisms of action. Comprehensive Reviews in Food Science and Food Safety, 1-44.
Tocmo R, Veenstra JP, Huang Y, Johnson JJ. Covalent modification of proteins by plant-derived natural products: proteomic approaches and biological impacts. Proteomics (Weinheim). (2020). 21:e1900386.
Tocmo, R, Parkin K. S-1-propenylmercaptocysteine protects murine hepatocytes against oxidative stress via persulfidation of Keap1 and activation of Nrf2. Free Radical Biology and Medicine, 2019, 143:164-75.
Özçam, M., Tocmo, R., Oh, J.-H., Afrazi, A., Mezrich, J.D., Roos, S., Claesen, J., & van Pijkeren, J. P. The gut symbionts Lactobacillus reuteri R2lc and 2010 encode a polyketide synthase cluster that activates the mammalian aryl-hydrocarbon receptor. Applied and Environmental Microbiology, 2018, 85(10), e01661-18.
Tocmo, R, Parkin, K. (2018). S-Alk(en)ylmercaptocysteine suppresses LPS-induced proinflammatory responses in murine macrophages through inhibition of NF-κB pathway and modulation of thiol redox status. Free Radical Biology and Medicine, 2018, 129:548-58.
Tocmo, R., Liang, D., Wang, C., Poh, J., & Huang, D. (2016). Organosulfide profile and hydrogen sulfide-releasing capacity of stinky bean (Parkia speciosa) oil: Effects of pH and extraction methods. Food Chemistry, 190, 1123-1129.
Tocmo, R., Liang, D., Lin, Y., & Huang, D. (2015). Chemical and biochemical mechanisms underlying the cardioprotective roles of dietary organopolysulfides. Frontiers in Nutrition, 2(1).
Tocmo, R., Lin, Y., & Huang, D. (2014). Effect of processing conditions on the organosulfides of shallot (Allium cepa L. Aggregatum Group). Journal of Agricultural and Food Chemistry, 62(23), 5296-5304.