Document Type
Oral Presentation
Location
Oxford Conference Center
Event Website
https://oxfordicsb.org/
Start Date
22-4-2026 1:00 PM
End Date
22-4-2026 1:20 PM
Description
Background and aims: Erica erigena grows abundantly along the west coast of Ireland, particularly in counties Mayo and Galway. The aim of the study was to evaluate its triterpenoid composition by GC-MS and NMR and to assess these compounds and fractionated terpenoid mixtures in vitro in cell proliferation, migration, and invasion assays, as well as ex vivo in aortic ring assays of angiogenesis and vasculature disruption. Methods: Plant material was collected at different times throughout the year (January, April, and September). GC-MS was used to profile the triterpenoid composition in free form using lithocholic acid as internal standard and BSTFA as derivatization reagent. NMR was used to characterize the coumaroyl triterpenes present. Individual coumaroyl triterpenes were synthesized for authentication purposes. HUVECs and PC-3 cells were used in the in vitro assays, while aorta from male Wistar rats was used for the ex vivo angiogenesis and vasculature disruption studies. Results: Pentacyclic triterpenes were the dominant terpenoid constituents, notably lupeol, ursolic acid, micromeric acid, and oleanolic acid, with minor amounts of uvaol, erythrodiol, α-/β-amyrone, lupenone, and ursolic aldehyde. Seasonal effects were significant with respect to lupeol content, ranging from 14,590.47 ± 267.64 μg/g in January to 5,048.03 ± 229.32 μg/g in September. The identity of the coumaroyl triterpenes as (E)/(Z)-coumaroyl conjugates of lupeol, α- and β-amyrin was confirmed by NMR analysis following their individual synthesis. This required an EDC/DMAP coupling step to generate the trans isomers while their conversion to the corresponding cis isomers was mediated by UV light at 365 nm. Among the 11 fractionated samples tested, the lupeol (EEL-2), uvaol (EEL-5), and ursolic acid (EEL-10)–rich fractions demonstrated significant activity at 2.5 µg/mL across all in vitro and ex vivo assays. Micromeric acid (EEL-11) was the least effective, followed by the coumaroyl triterpene fraction (EEL-3). In general, the ethyl acetate leaf extract was more effective than the flower extract. Overall, the study demonstrates that Erica erigena is a rich source of bioactive pentacyclic triterpenes with seasonal and tissue-dependent variation.
Recommended Citation
Walsh, John and Jabal, Khadijah, "Phytochemical and anticancer studies on the terpenoid constituents in Erica erigena" (2026). Oxford ICSB. 26.
https://egrove.olemiss.edu/icsb/2026_ICSB/Schedule/26
Publication Date
April 2026
Phytochemical and anticancer studies on the terpenoid constituents in Erica erigena
Oxford Conference Center
Background and aims: Erica erigena grows abundantly along the west coast of Ireland, particularly in counties Mayo and Galway. The aim of the study was to evaluate its triterpenoid composition by GC-MS and NMR and to assess these compounds and fractionated terpenoid mixtures in vitro in cell proliferation, migration, and invasion assays, as well as ex vivo in aortic ring assays of angiogenesis and vasculature disruption. Methods: Plant material was collected at different times throughout the year (January, April, and September). GC-MS was used to profile the triterpenoid composition in free form using lithocholic acid as internal standard and BSTFA as derivatization reagent. NMR was used to characterize the coumaroyl triterpenes present. Individual coumaroyl triterpenes were synthesized for authentication purposes. HUVECs and PC-3 cells were used in the in vitro assays, while aorta from male Wistar rats was used for the ex vivo angiogenesis and vasculature disruption studies. Results: Pentacyclic triterpenes were the dominant terpenoid constituents, notably lupeol, ursolic acid, micromeric acid, and oleanolic acid, with minor amounts of uvaol, erythrodiol, α-/β-amyrone, lupenone, and ursolic aldehyde. Seasonal effects were significant with respect to lupeol content, ranging from 14,590.47 ± 267.64 μg/g in January to 5,048.03 ± 229.32 μg/g in September. The identity of the coumaroyl triterpenes as (E)/(Z)-coumaroyl conjugates of lupeol, α- and β-amyrin was confirmed by NMR analysis following their individual synthesis. This required an EDC/DMAP coupling step to generate the trans isomers while their conversion to the corresponding cis isomers was mediated by UV light at 365 nm. Among the 11 fractionated samples tested, the lupeol (EEL-2), uvaol (EEL-5), and ursolic acid (EEL-10)–rich fractions demonstrated significant activity at 2.5 µg/mL across all in vitro and ex vivo assays. Micromeric acid (EEL-11) was the least effective, followed by the coumaroyl triterpene fraction (EEL-3). In general, the ethyl acetate leaf extract was more effective than the flower extract. Overall, the study demonstrates that Erica erigena is a rich source of bioactive pentacyclic triterpenes with seasonal and tissue-dependent variation.
https://egrove.olemiss.edu/icsb/2026_ICSB/Schedule/26
Comments
Assoc Prof John J. Walsh, BA (Mod.), PhD, is an Associate Director of the NatPro Centre at Trinity College Dublin. He graduated from Trinity College Dublin with a BA (Mod) Chemistry in 1990 and PhD in 1994. Following postdoctoral work with his PhD supervisor, Professor Tony Davis, he then moved in 1994 to the School of Pharmacy in TCD to conduct research with Dr Neil Frankish and Dr Helen Sheridan on the design of novel mast cell stabilising compounds. He joined the lecturing staff in the school in 1997 and since then has led several drug design programs focused on the discovery of new therapies for the treatment of cancer, malaria and allergic conditions. His research is conducted across many fields with particular emphasis now placed on the phytochemical and biological evaluation of Irish bogland plants and related species. Other aspects of his research are focused on the design and synthesis of hybrid-based compounds, “designed multiple ligands” and targeted therapies and their subsequent in vitro and in vivo evaluation in a range of disease models. He has multiple peer reviewed publications as senior author in diverse journals including Journal of Natural Products, Angiogenesis, British Journal of Pharmacology, Pharmaceutical Research, Current Medicinal Chemistry, Current Pharmaceutical Design, European Journal of Medicinal Chemistry, Bioorganic and Medicinal Chemistry Letters, Chemical Communications and the Journal of Chemical Education. He has supervised twenty-three postgraduate students to completion (19 x PhD and 4 x MSc). He lectures to undergraduate pharmacy students, to postgraduate students taking the MSc in Pharmaceutical Analysis and Diploma/MSc students in Pharmaceutical Manufacturing Technology. He is a very strong advocate of research-led teaching and has published many teaching methods on the isolation of nature-derived medicines as well as publications relating to aspects of integration of science and practice in the pharmacy curriculum. Assoc Prof Walsh has served as an undergraduate external examiner at NUI Maynooth, RCSI and at Galway Mayo Institute of Technology (now Atlantic Technological University). He served as the Director of Undergraduate Teaching and Learning from 2016-2020 which coincided with the rollout of the new Five Year Fully (Integrated) Master’s Degree Programme in Pharmacy. Since 2015, he is the Ireland representative on Committee 13B (Phytochemistry) of the European Pharmacopoeia, Strasbourg. Assoc Prof Walsh is the recipient of several awards including commendation on being selected for a Provost’s Teaching Award, Bioorganic and Medicinal Chemistry Letters - Most Cited Article 2003 to 2010 and Henkel Award for Excellence in Organic Chemistry.