beta-Amyrin acetate

Food Chem Toxicol. 2014 Feb;64:225-30.

Discovery of soluble epoxide hydrolase inhibitors from natural products.[Pubmed: 24309146]

With the goal of developing soluble epoxide hydrolase (sEH) inhibitors with novel chemical structures, the sEH inhibitory activities of 30 natural compounds were evaluated using both a fluorescent substrate, 3-phenyl-cyano(6-methoxy-2-naphthalenyl)methyl ester- 2-oxiraneacetic acid, and a physiological substrate, 14,15-epoxyeicosatrienoic acid.
METHODS AND RESULTS:
To evaluate the selectivity of sEH inhibition, the inhibition of microsomal epoxide hydrolase (mEH), which plays a critical role in detoxification of toxic epoxides, was determined using human liver microsomes. Honokiol and β-amyrin acetate, isolated from Magnolia officinalis and Acer mandshuricum, respectively, displayed strong inhibition of sEH activity, with respective IC50 values of 0.57 μM and 3.4 μM determined using the fluorescent substrate, and 1.7 μM and 6.1 μM determined using 14,15-epoxyeicosatrienoic acid. mEH activity was decreased to 49% or 61% of control activity by 25 μM honokiol or β-amyrin acetate, respectively.
CONCLUSIONS:
These results suggest that β-amyrin acetate and honokiol exhibit sEH inhibitory activity, although their sEH selectivity should be improved.

Asian Pac J. Trop. Biomed., 2012, 2(2):S981–S4.

Antioxidant and Cytotoxicity of β-Amyrin acetate fraction from Bridelia ferruginea Leaves.[Reference: WebLink]

The objective of this work was to determine the beta-Amyrin acetate fraction in leave extract of Bridelia ferruginea and evaluate for its antioxidant and cytotoxicity potentials.
METHODS AND RESULTS:
The dried and pulverized leaves of Bridelia ferruginea was extracted with hexane and then with ethyl acetate. The concentrated ethylacetate extract subjected to silica gel column chromatography and eluted with a mixture of equal volume of hexane and dichloromethane afforded two major fractions. The more polar fraction was concentrated and subjected to GCMS analysis which afforded the steroid, 12-Oleanen-3yl acetate commonly known as beta-Amyrin acetate (66.14%). Its ability to act as a scavenger of DPPH radical and its cytotoxicity potential based on brine shrimp assay were investigated. The DPPH antioxidant assay revealed that the fraction had a higher antioxidant potential with an IC50 value of 158.2μg/mL relative to gallic acid which had IC50 of 201.1 μg/mL. The cytotoxicity assay using the brine shrimp a gave LC50 values of 319 and 5.86 μg/mL for acute and lethal doses respectively indicating extreme toxicity when compared to reference drug, cyclophosphamide which had LC50 value of 2506 μg/mL.
CONCLUSIONS:
Thus, the beta-Amyrin acetate has been identified for the first time in the leave of Bridelia ferruginea. The data here suggest that the beta-Amyrin acetate fraction of the leave of Bridelia ferruginea could be further explored in biological profiling requiring antioxidant and cytotoxic dependent therapeutics as the plant could be a viable source of antioxidant and cytotoxic agents in cancer chemotherapy in the near future.

Pharm Biol. 2014 Nov;52(11):1478-86.

beta-Amyrin and alpha-amyrin acetate isolated from the stem bark of Alstonia boonei display profound anti-inflammatory activity.[Pubmed: 25026352]

To investigate the anti-inflammatory potential of beta-Amyrin acetateand α-amyrin acetate isolated from the stem bark of Alstonia boonei using animal models.
METHODS AND RESULTS:
Chromatographic purification of the crude methanol extract led to the isolation and structure elucidation of beta-Amyrin acetate and α-amyrin acetate.Both beta-Amyrin acetate and α-amyrin acetate inhibited heat-induced hemolysis to as much 47.2 and 61.5%, respectively, while diclofenac sodium (100 μg/mL) evoked only 40.5% inhibition. Both compounds at 100 µg/ear produced significant (p < 0.01) inhibition of ear edema in mice by 39.4 and 55.5%, respectively. Also at 100 mg/kg (p.o.) α-amyrin acetate evoked 60.3% reduction in total leucocyte count and significant (p < 0.05) suppression (47.9%) of neutrophil infiltration.
CONCLUSIONS:
This study generally provided evidence of profound anti-inflammatory activity of beta-Amyrin acetate and α-amyrin acetate isolated from the Alstonia boonei stem bark.

Phytomedicine. 2012 Jun 15;19(8-9):682-5.

β-Amyrin acetate and β-amyrin palmitate as antidyslipidemic agents from Wrightia tomentosa leaves.[Pubmed: 22541636]

The ethanolic extract and fractions of Wrightia tomentosa Roem. & Schult (Apocynaceae) leaves were tested in vivo for their antidyslipidemic activity in high fat diet (HFD) induced dyslipidemic hamsters.
METHODS AND RESULTS:
Activity guided isolation resulted in identification of antidyslipidemic compounds beta-Amyrin acetate and β-AP. Compounds beta-Amyrin acetate and β-AP decrease the levels of LDL by 36% and 44%, and increase the HDL-C/TC ratio by 49% and 28%, respectively, at a dose of 10mg/kg. In addition, the isolated compounds beta-Amyrin acetate and β-AP showed significant HMG-CoA-reductase inhibition, which was further established by docking studies.

J Oleo Sci. 2010;59(6):273-80.

Anti-inflammatory and chemopreventive effects of triterpene cinnamates and acetates from shea fat.[Pubmed: 20484832]

METHODS AND RESULTS:
Four triterpene acetates, alpha-amyrin acetate (1a), beta-Amyrin acetate (2a), lupeol acetate (3a), and butyrospermol acetate (4a), and four triterpene cinnamates, alpha-amyrin cinnamate (1c), beta-amyrin cinnamate (2c), lupeol cinnamate (3c), and butyrospermol cinnamate (4c), were isolated from the kernel fat (n-hexane extract) of the shea tree (Vitellaria paradoxa; Sapotaceae). Upon evaluation of these eight triterpene esters for inhibitory activity against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation (1 microg/ear) in mice, all of the compounds tested exhibited marked anti-inflammatory activity, with ID50 values in the range of 0.15-0.75 micromol/ear, and among which compound 3c showed the highest activity with ID(50) of 0.15 micromol/ear. Compound 3c (10 mg/kg) further exhibited anti-inflammatory activity on rat hind paw edema induced by carrageenan, with the percentage of inflammation at 1, 3, and 5 h of 35.4, 41.5, and 45.5%, respectively. The eight triterpene esters were then evaluated for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) in Raji cells as a primary screening test for inhibitors of tumor promoters.
CONCLUSIONS:
All the compounds showed moderate inhibitory effects. Furthermore, compound 3c exhibited inhibitory effect on skin tumor promotion in an in vivo two-stage carcinogenesis test using 7,12-dimethylbenz [a] anthracene (DMBA) as an initiator and TPA as a promoter. The biological activities of triterpene acetate and cinnamate esters, together with the exceptionally high levels of these triterpenes in shea fat, indicate that shea nuts and shea fat (shea butter) constitute a significant source of anti-inflammatory and anti-tumor promoting compounds.

Phytochem. Lett., 2011, 4(4):421-5.

Ovarian antiproliferative activity directed isolation of triterpenoids from fruits of Eucalyptus camaldulensis Dehnh[Reference: WebLink]

METHODS AND RESULTS:
Bioassay-guided fractionation of a methanol extract of the fruits of Eucalyptus camaldulensis Dehnh. with moderate antiproliferative activity afforded the new triterpene, 3β-acetoxy-urs-11,13(18)-dien-28-oic acid (1) along with the known triterpenoids 3β-hydroxy-urs-11-en-28,13β-olide (2), 3β-acetoxy-urs-11-en-28,13β-olide (3), 3-acetylbetulinic acid (4), oleanolic acid (5), ursolic acid (6), beta-Amyrin acetate (7), β-sitosterol (8) and sitosterol 3-O-β-D-glucopyranoside (9). Their structures were established on the basis of analysis of their 1H and 13C NMR, APT, gHSQC, gHMBC, UV, IR and mass spectral data.
CONCLUSIONS:
The tested triterpenoids (1–7) exhibited weak-moderate antiproliferative activity against the A2780 human ovarian cancer cell line.