Triterpenoid Components from Oak Heartwood (Quercus robur) and Their Potential Health Benefits

Abstract

For centuries oak wood (Quercus robur) has been used in aging of wines and spirits, which is based on pleasant flavors given to beverages by phenolics transferred to the liquid during the maturation process. Other metabolites, such as triterpenoids, can also be released. Searching for extractable triterpenoids in oak heartwood, 12 new, 1-12, and five known, 13-17, oleanane types were isolated and characterized. Their cytotoxicities were tested against cancer cells (PC3 and MCF-7) and lymphocytes. Breast cancer cells (MCF-7) were the most affected by triterpenoids, with roburgenic acid, 4, being the most active compound (IC = 19.7 μM). Selectivity was observed for compounds 1-3, 8, 9, and 16, exhibiting an IC > 200 μM against lymphocytes, while active against cancer cells. A galloyl unit attached to the triterpenoid moiety was established as the key feature for such effect. These results highlight the occurrence of triterpenoids in oak heartwood and their relevance for chemoprevention of breast cancer.

Medicinal Uses, Phytochemistry, and Pharmacological Activities of Quercus Species

“…Using HRESIMS and 1D/2D NMR experiments, Gammacurta et al [ 89 ] screened EtOAc extracts from the Quercus petraea heartwood for phytochemical investigations and isolated eight new triterpenoids (1−8) ( Figure 2(b) ) and two known functionalized triterpenoids. Posteriorly, Perez et al [ 90 ] in their study, identified 12 new triterpenoids, 1−12 ( Figure 2(c) ), and five known oleanane types which showed cytotoxicity activity against cancer cells (PC3 and MCF-7) and lymphocytes.…”

“…Perez et al [ 90 ] studied the cytotoxic activity of 17 triterpenoids isolated from oak heartwood of Quercus robur against human prostate cancer (PC3) and human estrogen-dependent breast adenocarcinoma (MCF-7) cell lines and lymphocytes derived from human peripheral blood. The obtained results demonstrate that breast cancer cells (MCF-7) were the most affected by triterpenoids, with roburgenic acid, being the most active compound (IC50 = 19.7 μ M).…”

“…(b)) and two known functionalized triterpenoids. Posteriorly, Perez et al[90] in their study, identified 12 new triterpenoids, 1−12(Figure 2(c)), and five known oleanane types which showed cytotoxicity activity against cancer cells (PC3 and MCF-7) and lymphocytes.Previously, three new 24-noroleanane triterpenoids, 2a,19a-dihydroxy-3-oxo-24-norolean-12-en-28-oic acid, 19a-hydroxy-3-oxo-24-norolean-12-en-28-oic acid, and 2a,3b,19a-trihydroxy-24-norolean-12-en-28-oic acid(Figure 1(d)), were also isolated from Q. aliena var. acuteserrata, with previously known compounds (bartogenic acid, ilexgenin, and aophitolic acid)[88].…”

“…(b) Eight new triterpenoids (1−8) isolated from Q. petraea[89]. (c) 12 new triterpenoids identified from oak heartwood Q. robur[90].…”

Integrated metabolomics and transcriptomics study of traditional herb Astragalus membranaceus Bge. var. mongolicus (Bge.) Hsiao reveals global metabolic profile and novel phytochemical ingredients

“…Taken together, 2190 metabolites from AMM were annotated by our integrated bioinformatics pipeline (Additional file 3). Among them, the most abundant are Terpenoids (254), followed by Flavonoids (101), Alkaloids (97), Phenylpropanoids (57), and Fatty acids related compounds (35) ( Table 1). We found an unprecedented number of metabolites from AMM, for which we have increased the number of annotated metabolites by an order of magnitude over previous studies.…”