MS Thesis Defense by Jillian A. Mauk, "Cranberry Pomace Components as a Source of Anti-Inflammatory Natural Products"
Violette 210
Heather Blaser
508-999-8587
hblaser@umassd.edu
https://us05web.zoom.us/j/86158392178?pwd=CNnJeosGsAqCSinlgFWxrghZU60hbC.1
Title: Cranberry Pomace Components as a Source of Anti-Inflammatory Natural Products
Advisor: Dr. Catherine Neto, Chemistry & Biochemistry Dept.
Committee Members: Dr. Shuowei Cai, Chemistry & Biochemistry Dept. & Dr. Brian Blanchette, Chemistry & Biochemistry Dept.
Abstract:
The American cranberry (Vaccinium macrocarpon) is a large red berry variety native to North America known for their bioactive phytochemicals and primarily cultivated for its use in products such as juice, sauces, or other consumables. After the processing of cranberries for their products the skins, seeds, and other raw plant material is left behind as a sidestream product called pomace. Cranberries are known to contain phytochemicals such as phytosterols, tocopherols, and most importantly for this study, triterpenoids. Based on previous work by the group, pomace contains the highest concentration of these triterpenoids by mass compared to other cranberry products and raw materials. Work has been done previously to establish the chemopreventive and anti-inflammatory potential of cranberry extracts rich in triterpenoids, specifically the pentacyclic triterpenoids: ursolic acid and its hydroxycinnamoyl esters. The relative contributions between the cranberry peel and flesh compared to the contribution from seeds, to the abundance of natural products and bioactivities of cranberry pomace, is under-explored.
Ultrasound-assisted extraction was used to isolate potential bioactive compounds from whole pomace, seedless pomace, and seed only samples. Using vacuum liquid chromatography, fractionation of the seedless pomace extract was performed to isolate compounds of interest and further analyze the bioactivities of the seedless pomace extract compared to whole pomace. A fraction containing primarily hydroxycinnamoyl esters was also isolated using column chromatography for further analysis of the phytochemicals’ activities. Characterization using UPLC-MS and GC-MS of the extracts was performed to identify and quantify natural compounds such as triterpenoids, phytosterols, and tocopherols. With seedless pomace extracts containing a higher quantity of triterpenoids than whole pomace, highlighting the abundance of these compounds within the peel of the fruit versus seeds.
Anti-inflammatory screening was performed to determine the ability of extracts, fractions and specific compounds in the pomace to inhibit pro-inflammatory enzyme soluble epoxide hydrolase (sEH). sEH hydrolyzes anti-inflammatory epoxyeicosatrienoic acids (EETs), derived from arachidonic acid, into mostly bio-inactive dihydroxyeicosatrienoic acids (DHETs), which increases net inflammation in the body. Seedless pomace extracts showed a higher anti-inflammatory potential than the whole pomace counterpart. Out of the fractions, SPD.2 had the lowest IC50 while also being the fraction with the highest concentration of triterpenoids and hydroxycinnamoyl esters. Correlation assessment done via multivariate analysis revealed that the hydroxycinnamoyl esters have the strongest overall association with sEH inhibition out of the compounds analyzed. All four esters individually had the highest Pearson correlations and VIP scores, suggesting a pharmacological significance in the esterified forms of the triterpenoids.
The quantitative and bioactivity results indicate that isolating cranberry pomace components, and preparing extracts rich in ursolic and oleanolic acid and their derivatives, is a potential way to maximize the efficacy of the pomace in pharmacological applications.
Meeting ID: 861 5839 2178
Password: JaMXyZ
Meeting link: https://us05web.zoom.us/j/86158392178?pwd=CNnJeosGsAqCSinlgFWxrghZU60hbC.1