Chemical Composition and Cytotoxic Activity of the Essential Oil and Oleoresins of In Vitro Micropropagated Ansellia africana Lindl: A Vulnerable Medicinal Orchid of Africa.

Orchids are rich treasure troves of various important phytomolecules. Among the various medicinal orchids, Ansellia africana stands out prominently in the preparing of various herbal medicines due to its high therapeutic importance. The nodal explants of A. africana were sampled from asymbiotically germinated seedlings on basal Murashige and Skoog (MS) medium and were micropropagated in MS medium supplemented with 3% sucrose and 10 µM meta topolin (mT) + 5 µM naphthalene acetic acid (NAA) +15 µM indole butyric acid (IBA) + 30 µM phloroglucinol (PG). In the present study, the essential oil was extracted by hydrodistillation and the oleoresins by the solvent extraction method from the micropropagated A. africana. The essential oil and the oleoresins were analysed by Gas Chromatography (GC) and GC/MS (Mass spectrometry). A total of 84 compounds were identified. The most predominant components among them were linoleic acid (18.42%), l-ascorbyl 2,6-dipalmitate (11.50%), linolenic acid (10.98%) and p-cresol (9.99%) in the essential oil; and eicosane (26.34%), n-butyl acetate (21.13%), heptadecane (16.48%) and 2-pentanone, 4-hydroxy-4-methyl (11.13%) were detected in the acetone extract; heptadecane (9.40%), heneicosane (9.45%), eicosane (6.40%), n-butyl acetate (14.34%) and styrene (22.20%) were identified and quantified in the ethyl acetate extract. The cytotoxic activity of essential oil and oleoresins of micropropagated A. africana was evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium Bromide) assay on Vero cells compared to the standard drug doxorubicin chloride. The present research contains primary information about the therapeutic utility of the essential oil and oleoresins of A. africana with a promising future research potential of qualitative and quantitative improvement through synchronised use of biotechnological techniques.

Identification of a precursor of 2-mercapto-3-methyl-1-butanol in beer.

2-Mercapto-3-methyl-1-butanol (2M3MB) imparts an onion-like off-flavor to beer and is believed to result from the hot aeration of brewer's wort. However, little has been reported regarding the mechanism of formation of 2M3MB. This paper investigates the precursors of 2M3MB formed during the brewing process. Our study of a cysteine conjugate as a precursor showed its negligible contribution to the formation of 2M3MB. The 2M3MB precursor was found to be a volatile compound because 2M3MB was formed in the distillate of hop extract. The precursor was purified through distillation, column chromatography, and preparative gas chromatography, and the 2M3MB-producing potential was measured as an index for estimating the concentration of the precursor. The accurate mass of the precursor was measured using gas chromatography coupled to quadrupole-time-of-flight-mass spectrometry (GC/QTOF). The molecular structure was identified from the product ion spectra by GC/QTOF to be 2,3-epoxy-3-methylbutanal.

Hepatoprotective effects of polyprenols from Ginkgo biloba L. leaves on CCl4-induced hepatotoxicity in rats.

The hepatoprotective effects of polyprenols from Ginkgo biloba L. leaves were evaluated against carbon tetrachloride induced hepatic damage in Sprague-Dawley rats. The elevated levels of serum ALT, AST, ALP, ALB, TP, HA, LN, TG, and CHO were restored towards normalization significantly by GBP in a dose dependent manner. The biochemical observations were supplemented with histopathological examination of rat liver sections. Meanwhile, GBP also produced a significant and dose-dependent reversal of CCl(4)-diminished activity of the antioxidant enzymes and reduced CCl(4)-elevated level of MDA. In general, the effects of GBP were not significantly different from those of the standard drug Essentiale.

[Studies on purification of polyprenol from Ginkgo biloba L. leaves].

OBJECTIVE: To research the methods of purifying polyprenol from leaves of Ginkgo biloba L.. METHODS: The purity of polyprenol was determined by HPLC to select the optimal purifying conditions. RESULTS: The optimal conditions were degreased by 160 times of petroleum ether-ethyl acetate (9:1) firstly, then through a silica gel column (100-140 mesh) and eluted with petroleum etherethyl acetate (19:1). CONCLUSION: The methods are feasible to purify polyprenol from leaves of Ginkgo biloba L. and could increase the purity of polyprenol obviously.

[Prophylactic efficacy of aerosol preparations based on Abies siberica polyprenols in experimental influenza infection]. / Profilakticheskaia éffektivnost' aérozolei preparatov na osnove poliprenolov pikhty sibirskoi pri éksperimental'noi grippoznoi infektsii.

Preliminary investigations showed high preventive activity of two of three aerosol preparations of Abies sibirica polyprenols with nonionic surface active substances towards influenza infection. At least 2 aerosol administrations are needed to attain a high protective effect, the second dose depending on the first. Relationship between animal reaction to influenza virus infection changed in a nonmonotonous mode, depending on the drug dose injected during the first treatment: as the dose increased, the death rate first decreased and reached the minimum and then increased again. Such a reaction to aerosol treatment can be explained by the hypothesis of hyperstimulation followed by exhaustion of the host defense systems after high doses of the preparation.

3-Mercapto-2-methylpentan-1-ol, a new powerful aroma compound.

3-Mercapto-2-methylpentan-1-ol was first detected in a complex thermally processed flavor and finally isolated from raw onions. The chemical structure of this new compound was identified by MS and (1)H NMR measurement and synthesis of the proposed structure. Sensory evaluation at different concentrations indicated that the flavor quality is strongly dependent on concentration. At low concentration (0.5 ppb) a pleasant meat broth, sweaty, onion, and leek-like odor can be perceived. On the basis of some isolation experiments and volatiles occurring in raw onions, a formation pathway is proposed. As one intermediate 3-mercapto-2-methylpentanal, another new strong flavor compound, was suggested. The presence of this compound in raw onions was confirmed by synthesis and comparison of MS and chromatographic data.

[Studies on the structure of alpha-trans-bergamotenol from Chinese santalwood oil].

A new sesquiterpenol was isolated from santalwood oil (Santalum album L., Santalaceae). Its structure and relative stereochemistry were elucidated on the basis of spectral analysis (IR, MS, 1H-1H COSY, 13C-1H COSY and 1H-1H NOESY) as 9(10)Z, alpha-trans-bergamotenol (Ia).

[Sedative-hypnotic compounds in the exhalation of hops, II]. / Versuche, sedativ-hypnotische Wirkstoffe im Hopfen nachzuweisen, II.

Hops are told to promote sleep; manyfold efforts to detect the soporific principle have been unsuccessful so far. Preliminary pharmacological tests lead to the conclusion that the soporific activity of the exhalation of hops can be explained by its content of 2-methyl-3-butene-2-ol (1) in the volatile fraction. It was found that 1, when given to mice i.p. (0.80 g/kg) produces narcosis for about 8 h; no abnormal behaviour was observed there upon. Due to its water-solubility the concentration of 1 in the essential oil obtained by steam-distillation is low; contrary to that, 1, is enriched in the more volatile fraction of hops.