Cytotoxic Activities of Extracts and Compounds from Viscum coloratum and its Transformation Products by Rhodobacter sphaeroides

Abstract

The bioassay-oriented fractionation of mistletoe crude extracts (MCEE) using 75% ethanol and culture products of mistletoe transformed by Rhodobacter sphaeroides, a photosynthetic bacterium (PSBT), revealed that the high cytotoxic activities were due to the petroleum ether extracts (PEs) and the acid-precipitated proteins from the aqueous extracts (AQs) of MCEE and PSBT. The isolated triterpenes may account for the activities of the PEs of MCEE and PSBT, respectively. Extraction of MCEE using petroleum ether led to the isolation of 3-epi-betulinic acid (1), betulonic acid (2), oleanolic acid (3), and beta-amyrin acetate (4), while petroleum ether extraction of PSBT led to the isolation of 1,3,4,betulinic acid (5), erythrodiol (6), and (3beta)-olean-12-ene-3,23-diol (7). The PE of PSBT exerted higher cytotoxicity than the PE of MCEE, which was due to the different triterpene contents of these two extracts. The cytotoxic activities of all compounds were tested, and the results revealed that compounds 1, 2, 3, 5, 6, and 7 contributed significantly to the cytotoxicities of both PEs. The AQ of the PSBT exerted almost the same cytotoxic activity and lower toxicity compared to the AQ of the MCEE. These findings indicate that mistletoe products biotransformed by R. sphaeroides could be used to treat cancers, since they have lower toxicities and higher antitumor activities compared to standard treatments.

Chemical Constituents and Cytotoxic Effect of the Main Compounds of Lythrum salicaria L.

“…Our results corroborate an earlier fi nding holding erythrodiol (14) to be responsible for the cytotoxic effect of Viscum coloratum against HO-8910 and SMMC-7721 cells (Yang et al, 2009). Furthermore, its mechanism of action has revealed that it has antiproliferative and pro-apoptotic activity toward the HT-29 cell line (Juan et al, 2008).…”

X-Ray Diffraction and Infrared Spectroscopy of N,N- Dimethylformamide and Dimethyl Sulfoxide Solvatomorphs of Betulonic Acid

“…Betulonic acid is a white solid that exhibits limited solubility in organic solvents such as methanol, ethanol, chloroform, and ether and it also shows low solubility in water. Various solvents used in the crystallization process and different melting points reported earlier, for example, 244°C–246°C,5,6 246°C–248°C,4 and 258°C,7 may indicate the existence of several crystal polymorphic or solvatomorphic forms of BA. Solvatomorphism can be defined as the ability of the compound to form several crystal unit cells, which differ in their structure and elemental composition due to the inclusions of solvent molecules 9,10.…”

“…Betulonic acid can be isolated from the various plants, for example, Betula pubescens ,4 Viscum coloratum ,5,6 and Ainsliaea acerifolia 7. It is also known as a derivative of betulin, which is one of the most plentiful triterpenes comprising up to 30% dry weight of the outer bark of the white birch.…”

Ferruginenes A−C from Rhododendron ferrugineum and Their Cytotoxic Evaluation

“…Ursolic, oleanolic, and corosolic acids have been reported to exhibit cytotoxic activity against various cell lines. − Ursolic acid induced apoptosis via the suppression of NF-kB-mediated activation of Bcl-2 in melanoma cells and the activation of caspase-dependent and -independent pathways in prostate cancer cells . Oleanolic acid caused intracellular calcium increase and apoptosis in human lung adenocarcinoma cells, while corosolic acid triggered apoptosis through the mitochondrial pathway in HeLa cells .…”