BEGIN:VCALENDAR VERSION:2.0 X-WR-CALNAME:EventsCalendar PRODID:-//hacksw/handcal//NONSGML v1.0//EN CALSCALE:GREGORIAN BEGIN:VTIMEZONE TZID:America/New_York LAST-MODIFIED:20240422T053451Z TZURL:https://www.tzurl.org/zoneinfo-outlook/America/New_York X-LIC-LOCATION:America/New_York BEGIN:DAYLIGHT TZNAME:EDT TZOFFSETFROM:-0500 TZOFFSETTO:-0400 DTSTART:19700308T020000 RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=2SU END:DAYLIGHT BEGIN:STANDARD TZNAME:EST TZOFFSETFROM:-0400 TZOFFSETTO:-0500 DTSTART:19701101T020000 RRULE:FREQ=YEARLY;BYMONTH=11;BYDAY=1SU END:STANDARD END:VTIMEZONE BEGIN:VEVENT CATEGORIES:College of Arts and Sciences,Lectures and Seminars,Thesis/Disser tations DESCRIPTION:Title: Cranberry Leaf Extracts as a Tool Against Staphylcoccu s aureus: Composition and Biofilm Inhibitory Properties by Kyla Lockhart A dvisor: Dr. Catherine Neto, Chemistry & Biochemistry Dept. Committee Members: Dr. Shuowei Cai, Chemistry & Biochemistry Dept. & Dr. Frank Scarano, Medical Labratory Science Abstract: Biofilm is a community of micro-organisms which forms as a means of protection. This community helps to protect the bacteria from its environment and to adhere to different s urfaces. Staphylococcus aureus is a common gram-positive bacterial pathoge n bacteria which forms biofilm by producing extracellular polysaccharide ( EPS). This process allows these bacteria to spread and become harder to ki ll as the EPS makes it more resistant to antibiotics. Cranberries are know n for their antibacterial effects due to the proanthocyanidins (PACs) they contain. While there has been much research on the cranberry fruit, there is less known about the chemistry and antibacterial properties of the cra nberry leaves. Through bioassay-guided fractionation of leaf extracts usin g Sephadex-LH20 chromatography and LCMS and GCMS analysis we were able to characterize cranberry leaf fractions and observe their anti-biofilm effec ts on S. aureus. In the biofilm formation and eradication assays, fraction EDII was the most effective, with inhibition of 88% and 78% respectively at a concentration of 12.5 µg/mL. EDII was found to contain isomers of th e phenolic compound p-coumaroylquinic acid and was further separated into subfractions which were analyzed through LCMS and biological testing. The best result for biofilm inhibition was obtained for fraction F5 with 83% a nd the best biofilm eradication was obtained for fraction F4 with 68%. The se fractions were found to contain 1-p-coumaroylquinic acid, 5-p-coumaroyl quinic acid and chicoric acid which may contribute to their anti-bacterial and antioxidant effects. ED fractions and subfractions were also tested f or antioxidant activity using the DPPH assay. Many of these fractions had promising free radical scavenging activity, with the the most promising re sults observed for fractions EDVI and EDVII and subfraction F5 which had I C50 values of 3.64, 1.21, and 17.7 µg/mL respectively. Overall, these fin dings demonstrate that cranberry leaves contain strong anti-biofilm and an tioxidant properties which suggests they have potential as a natural antim icrobial source and sets the foundation for future studies in isolation an d characterization of active compounds and their activity.\nEvent page: ht tps://www.umassd.edu/events/cms/20260721-ms-thesis-defense-by-kyla-lockhar t.php X-ALT-DESC;FMTTYPE=text/html:

Title: Cranberry Leaf Extract s as a Tool Against Staphylcoccus aureus: Composition and Biofilm Inhibito ry Properties by Kyla Lockhart

Advisor: Dr. Catherine Neto\, C hemistry & Biochemistry Dept.

Committee Members: Dr. Shuowei Cai\, Chemistry & Biochemistry Dept. & Dr. Frank Scarano\, Medical Labrat ory Science

Abstract: Biofilm is a community of micro-organisms which forms as a means of protection. This community helps to protect the bacteria from its environment and to adhere to different surfaces. Staphy lococcus aureus is a common gram-positive bacterial pathogen bacteria whic h forms biofilm by producing extracellular polysaccharide (EPS). This proc ess allows these bacteria to spread and become harder to kill as the EPS m akes it more resistant to antibiotics. Cranberries are known for their ant ibacterial effects due to the proanthocyanidins (PACs) they contain. While there has been much research on the cranberry fruit\, there is less known about the chemistry and antibacterial properties of the cranberry leaves. Through bioassay-guided fractionation of leaf extracts using Sephadex-LH2 0 chromatography and LCMS and GCMS analysis we were able to characterize c ranberry leaf fractions and observe their anti-biofilm effects on S. aureu s. In the biofilm formation and eradication assays\, fraction EDII was the most effective\, with inhibition of 88% and 78% respectively at a concent ration of 12.5 µg/mL. EDII was found to contain isomers of the phenolic c ompound p-coumaroylquinic acid and was further separated into subfractions which were analyzed through LCMS and biological testing. The best result for biofilm inhibition was obtained for fraction F5 with 83% and the best biofilm eradication was obtained for fraction F4 with 68%. These fractions were found to contain 1-p-coumaroylquinic acid\, 5-p-coumaroylquinic acid and chicoric acid which may contribute to their anti-bacterial and antiox idant effects. ED fractions and subfractions were also tested for antioxid ant activity using the DPPH assay. Many of these fractions had promising f ree radical scavenging activity\, with the the most promising results obse rved for fractions EDVI and EDVII and subfraction F5 which had IC50 values of 3.64\, 1.21\, and 17.7 µg/mL respectively. Overall\, these findings d emonstrate that cranberry leaves contain strong anti-biofilm and antioxida nt properties which suggests they have potential as a natural antimicrobia l source and sets the foundation for future studies in isolation and chara cterization of active compounds and their activity.

Event page: https://www.umassd.edu/events/cms/20260721-ms-thesis-defense -by-kyla-lockhart.php

DTSTAMP:20260710T140056 DTSTART;TZID=America/New_York:20260721T130000 DTEND;TZID=America/New_York:20260721T150000 LOCATION:SENG 307B SUMMARY;LANGUAGE=en-us:MS Thesis Defense by Kyla Lockhart, Cranberry Leaf E xtracts as a Tool Against Staphylcoccus aureus: Composition and Biofilm In hibitory Properties UID:f9dc7eae02ecb3613136528d0051f1eb@www.umassd.edu END:VEVENT END:VCALENDAR