Α-boswellic Acid Research Articles

Boswellic acid acetate induces apoptosis through caspase-mediated pathways in myeloid leukemia cells

The mechanism of the cytotoxic effect of boswellic acid acetate, a 1:1 mixture of alpha-boswellic acid acetate and beta-boswellic acid acetate, isolated from Boswellia carterri Birdw on myeloid leukemia cells was investigated in six human myeloid leukemia cell lines (NB4, SKNO-1, K562, U937, ML-1, and HL-60 cells). Morphologic and DNA fragmentation assays indicated that the cytotoxic effect of boswellic acid acetate was mediated by induction of apoptosis. More than 50% of the cells underwent apoptosis after treatment with 20 mug/mL boswellic acid for 24 hours. This apoptotic process was p53 independent. The levels of apoptosis-related proteins Bcl-2, Bax, and Bcl-XL were not modulated by boswellic acid acetate. Boswellic acid acetate induced Bid cleavage and decreased mitochondrial membrane potential without production of hydrogen peroxide. A general caspase inhibitor (Z-VAD-FMK) and a specific caspase-8 inhibitor II (Z-IETD-FMK) blocked boswellic acid acetate-induced apoptosis. The mRNAs of death receptors 4 and 5 (DR4 and DR5) were induced in leukemia cells undergoing apoptosis after boswellic acid acetate treatment. These data taken together suggest that boswellic acid acetate induces myeloid leukemia cell apoptosis through activation of caspase-8 by induced expression of DR4 and DR5, and that the activated caspase-8 either directly activates caspase-3 by cleavage or indirectly by cleaving Bid, which in turn decreases mitochondria membrane potential.

Characterization of archaeological frankincense by gas chromatography–mass spectrometry

A simple gas chromatography–mass spectrometry (GC–MS) method has been developed for the characterization of frankincense in archaeological samples. After trimethylsilylation of the methanolic extract, 15 triterpenoids have been found among the chemical constituents of commercial olibanum (α-boswellic acid, 3- O-acetyl-α-boswellic acid, β-boswellic acid, 3- O-acetyl-β-boswellic acid, α-amyrin, β-amyrin, lupeol, 3- epi-α-amyrin, 3- epi-β-amyrin, 3- epi-lupeol, α-amyrenone, β-amyrenone, lupenone, 3α-hydroxy-lup-20(29)-en-24-oic acid and 3- O-acetyl-hydroxy-lup-20(29)-en-24-oic acid). These compounds have been unequivocally identified by retention time and mass spectral comparison with pure standards previously isolated, for the most part, in our laboratory. Within these triterpenes, acid ones, the corresponding O-acetates, and their products of degradation were found to be characteristic of frankincense ( Boswellia resin). The presence of these unusual triterpenic compounds in an archaeological resinous sample, recovered during excavations from Dahshour site (Egypt, XIIth Dynasty), enabled us to identify unambiguously frankincense resin among several other materials. Additional chromatographic peaks of this sample were assigned to broad chemical classes using retention time and mass spectra features.

Immunomodulatory triterpenoids from the oleogum resin of Boswellia carterii Birdwood.

The immunomodulatory bioassay-guided fractionation of the oleogum resin of frankincense (Boswellia carterii Birdwood) resulted in the isolation and identification of 9 compounds; palmitic acid and eight triterpenoids belonging to lupane, ursane, oleanane, and tirucallane skeleta were isolated form the resin. These triterpenoids are lupeol, beta-boswellic acid, 11-keto-beta-boswellic acid, acetyl beta-boswellic acid, acetyl 11-keto-beta-boswellic acid, acetyl-alpha-boswellic acid, 3-oxo-tirucallic acid, and 3-hydroxy-tirucallic acid. The structures of the isolated compounds were deduced based on spectroscopic evidences. The lymphocyte transformation assay of the isolated compounds proved that the total extract retained more activity than that of any of the purified compounds.

A lupane triterpene from frankincense ( Boswellia sp., Burseraceae)

A new lupane-type triterpene, 3α-hydroxy-lup-20(29)-en-24-oic acid, was isolated from the methanolic extract of “Erytrean-type” resin of commercial frankincense together with the known 3α-hydroxy-olean-12-en-24-oic acid (α-boswellic acid) and 3α-hydroxy-urs-12-en-24-oic acid (β-boswellic acid). Their structures were characterized on the basis of chemical and spectral evidence including two dimensional NMR experiments and mass spectrometric techniques.

Chemical evidence for archaeological frankincense: Boswellic acids and their derivatives in solvent soluble and insoluble fractions of resin-like materials

α-Boswellic acid (3α-hydroxyolean-12-en-24-oic acid) and β-boswellic acid (3α-hydroxyurs-12-en-24-oic acid) and their acetates were identified in the solvent soluble fraction of samples of amorphous resin-like materials recovered from excavations at Qasr Ibrîm (Egyptian Nubia). The complementary 24-noroleana-3,12-diene and 24-norursa-3,12-diene were identified in pyrolysates of the residues where they were produced from the α- and β-boswellic acid and their acetates.

The 18α-epimer of α-boswellic acid: conformational diagnosis of triterpenoids by ultraviolet absorption spectroscopy

The synthesis of 18α-α-boswellic acid is reported and the hypsochromic shift in the u.v. absorption spectrum associated with the 18β→18α transformation is proposed as a diagnostic technique in conformational analysis.