Microbial-mediated release of bisphenol A from polycarbonate vessels.

AIM: To identify the source of bisphenol A (BPA) [2,2'-bis(4-hydroxyphenyl) propane] in cultures of an antibiotic-producing Bacillus sp. strain grown in polycarbonate flasks. METHODS AND RESULTS: Although a culture of an antibiotic-producing Bacillus sp. strain grown in a new, rinsed polycarbonate flask yielded BPA, duplicate cultures grown in thoroughly washed polycarbonate flasks did not. Cells of Escherichia coli strain C were grown in new polycarbonate flasks rinsed three-times with 100 ml distilled H2O. BPA was only recovered from cultures grown in new polycarbonate flasks, but not from the autoclaved medium incubated in parallel. CONCLUSIONS: BPA was present in either Bacillus or E. coli cultures, probably due to its release from inadequately washed polycarbonate flasks. Standard autoclaving did not result in BPA appearance; microbial growth was required. Polycarbonate vessels for microbial cultures should be thoroughly washed to avoid the appearance of BPA in culture medium. SIGNIFICANCE AND IMPACT OF THE STUDY: This study rigorously demonstrates that the presence of BPA in culture medium was a consequence of microbial growth or metabolism in inadequately washed polycarbonate flasks. As BPA exhibits antimicrobial and oestrogenic activity, searches for novel drugs or production of recombinant chemotherapeutic agents could be derailed by the artefactual appearance of BPA.

LC-MS and LC-PDA vs. phytochemical analysis of Colchicum brachyphyllum.

In this paper, reliability and validity of a recently in-house developed dereplication strategy based on LC-MS and LC-UV/Vis PDA techniques were verified. The dereplication strategy was applied to investigate the alkaloid rich fraction of Colchicum brachyphyllum Boiss. & Haussk. ex Boiss. (Colchicaceae) which has been previously analyzed phytochemically. Both studies results, LC-MS and LC-PDA and phytochemical analysis, were matched in seven compounds namely: (-)-colchicine (5), 3-demethyl-(-)-colchicine (4), (-)-cornigerine (7), beta-lumi-(-)-colchicine (6), (-)-demecolcine (3), 3-demethyl-(-)-demecolcine (2), and 2,3-didemethyl-(-)-demecolcine (1). LC-MS and LC-PDA based dereplication strategy was not able to detect two of the compounds that were reported in the phytochemical study namely: (+)-demecolcinone and (-)-androbiphenyline. This finding could raise a question about the "naturality" of (+)-demecolcinone. On the other hand apigenin (8) was identified only using this dereplication strategy. Four compounds which had molecular ions at m/z 372 and 400 in the stems, and at m/z at 372 and 358 in flowers, could not be dereplicated, and were thus considered unknown. Their spectral data were not matched with neither the compounds that have been isolated previously from this species nor with any other colchicinoid; hence they should be pursued as potential new compounds.

Determination of (-)-demecolcine and (-)-colchicine content in selected Jordanian Colchicum species.

In our continuing attempt to investigate Jordanian Colchicum species as a potential and viable source of colchicinoids; the distributions of the most interesting colchicinoid alkaloids (-)-demecolcine and (-)-colchicine in different plant parts of wildly growing C. crocifolium Boiss., C. ritchii R. Br., and C. triphyllum Kunze, were analyzed. The method is based on the use of external reference standards and a reversed-phase gradient HPLC. While (-)-colchicine was found in all plant parts of the three investigated Colchicum species, (-)-demecolcine was not detected in the leaves and daughter corms of C. triphyllum, the corms of C. crocifolium, and the flowers, stems, and mother and daughter corms of C. ritchii. C. triphyllum was found to be the highest in total (-)-colchicine content of 0.10% (wt/wt), while C. crocifolium was the highest in total (-)-demecolcine content of 0.09% (wt/wt). During flowering, leaves and corms in C. crocifolium, and leaves and stems in C. ritchii are the main storages of (-)-colchicine. (-)-Colchicine showed a homogenous distribution in all plant parts (stems, leaves, and mother and daughter corms) of C. triphyllum of 0.10% (wt/wt). Regarding (-)-demecolcine, stems and leaves of C. crocifolium, stems of C. triphyllum, and leaves of C. ritchii are the main storages. This work reports for the first time the presence of (-)-colchicine and (-)-demecolcine in C. crocifolium.

Liquid chromatographic-mass spectrometric method for quantitative determination of lisinopril in human plasma.

A validated liquid chromatographic-mass spectrometric (LC/MS) method for the determination of lisinopril in human plasma is presented. Enalapril was used as an internal standard. After the addition of internal standard, solid phase extraction was used as a cleaning step. To separate lisinopril and enalapril from interfering endogenous plasma substances, the analysis was performed using column switching valve. The quantitative determination was performed using selected ion monitoring (+)-electrospray LC-MS. A combination of an acidic mobile phase and a reverse phase column was used. A precision in the linear range from 10 to 500.0 ng/mL plasma, absolute recovery of 91.69% for lisinopril and 90.26% for enalapril, stability for 3.5 months at -20 degrees C have been achieved. Limit of quantitation (LOQ) was 10 ng/mL while limit of detection (LOD) was about 1 ng/mL.

Determination of colchicine content in Colchicum hierosolymitanum and Colchicum tunicatum under cultivation.

Corms of Colchicum hierosolymitanum and Colchicum tunicatum were collected, identified and planted under field condition. We report here and for the first time the presence of colchicine in an appreciable amount in both species. The effect of different NPK fertilizer levels on colchicine content of the two Colchicum species at different growth stages were evaluated by HPLC. Results indicated that increasing NPK fertilizer levels significantly improve colchicine content in different plant parts and stages. The highest colchicine content observed in corms was at maturity stage 0.766 mg/g and 0.688 mg/g dry weight with C. hierosolimitanum and C. tunicatum, respectively.

Two bioactive mono-tetrahydrofuran acetogenins, annoglacins A and B, from Annona glabra.

Two new bioactive mono-THF Annonaceous acetogenins, annoglacins A and B, have been isolated from the fractionated ethanolic extracts of the leaves of Annona glabra, directing the fractionation with the brine shrimp lethality test (BST). Their structures were elucidated based on spectroscopic and chemical methods and the absolute stereochemistries were determined by the advanced Mosher ester method. Annoglacins A and B were selectively 1000 and 10,000 times, respectively, more potent than adriamycin against the human breast carcinoma (MCF-7) and pancreatic carcinoma (PACA-2) cell lines in our panel of six human solid tumor cell lines.

Annonaceous acetogenins: recent progress.

The Annonaceous acetogenins are promising new antitumor and pesticidal agents that are found only in the plant family Annonaceae. Chemically, they are derivatives of long-chain fatty acids. Biologically, they exhibit their potent bioactivities through depletion of ATP levels via inhibiting complex I of mitochondria and inhibiting the NADH oxidase of plasma membranes of tumor cells. Thus, they thwart ATP-driven resistance mechanisms. This review presents the progress made in the chemistry, biology, and development of these compounds since December 1995.

Goniotriocin and (2,4-cis- and -trans)-xylomaticinones, bioactive annonaceous acetogenins from Goniothalamus giganteus.

Goniotricin (1) and a mixture of (2,4-cis and -trans)-xylomaticinones (2), new bioactive annonaceous acetogenins, were isolated from the bark of Goniothalamus giganteus (Annonaceae) by activity-directed fractionation using the brine shrimp lethality test. Compound 1 is the first nonadjacent ring-hydroxylated bis-tetrahydrofuran (THF) acetogenin to be reported. Compound 2 is the cis- and trans-ketolactone mixture of xylomaticin, a known compound whose absolute stereochemistry has not been previously determined. The absolute stereochemistry of 2 was determined by the advanced Mosher's ester method. Both 1 and 2 showed significant and selective cytotoxicities among the six tumor cell lines in our seven-day MTT human solid tumor panel. In the yellow fever mosquito larvae microtiter assay, 1 was quite active, with an ED50 value of 3. 5 microg/mL.

Annojahnin from Annona jahnii: a possible precursor of mono-tetrahydrofuran acetogenins.

A new cytotoxic Annonaceous acetogenin, annojahnin (1), was isolated from the twigs of Annona jahnii (Annonaceae) by bioactivity-directed fractionation using lethality to brine shrimp. Compound 1 represents an unusual type of C-37 Annonaceous acetogenin, lacking either tetrahydrofuran (THF) or epoxide rings, bearing a keto group at C-10, and possessing a double bond located two methylenes away from a vicinal diol. The structure and absolute configuration of 1 were elucidated by 1H and 13C NMR, COSY, and single-relayed COSY and from chemical derivatives. 4-Deoxy-18/21-trans-annomontacin 10-one (4) and 4-deoxy-18/21-cis-annomontacin-10-one (5), two semisynthetic mono-THF acetogenins, were prepared from 1 by reactions that mimic the biogenetic pathways. These acetogenins showed selective cytotoxicities, comparable or superior to adriamycin, among six human solid tumor cell lines. Reduction of the 10-keto of 1, to the racemic 10-OH derivative (3), retained the bioactivities as did the conversion of 1 to 4 and 5.

Mono-tetrahydrofuran acetogenins from Goniothalamus giganteus.

Goniotetracin and a mixture of (2,4-cis and trans)-gonioneninone, new, bioactive, mono-tetrahydrofuran (THF) gamma-lactone and ketolactone acetogenins, were isolated from the bark of Goniothalamus giganteus (Annonaceae) by activity-directed fractionation using the brine shrimp lethality test (BST). The structures were elucidated based on spectroscopic and chemical methods. Their absolute stereochemistries were determined by the advanced Mosher ester method. Both showed selective and significant cytotoxicities, comparable to the potency of adriamycin, to the human pancreatic tumour cell line (PACA-2), while goniotetracin and goniothalamicin were comparable to the activity of rotenone against yellow fever mosquito larvae.

Muricoreacin and murihexocin C, mono-tetrahydrofuran acetogenins, from the leaves of Annona muricata.

Bioactivity-directed fractionation of the leaves of Annona muricata L. (Annonaceae) resulted in the isolation of two new Annonaceous acetogenins, muricoreacin (1) and murihexocin C (2). Compounds 1 and 2 showed significant cytotoxicities among six human tumor cell lines with selectivities to the prostate adenocarcinoma (PC-3) and pancreatic carcinoma (PACA-2) cell lines.

Glabracins A and B, two new acetogenins from Annona glabra.

Two new bioactive bis-THF Annonaceous acetogenins, glabracins A (1) and B (2), and two previously known acetogenins, javoricin (3) and bullatanocin (4), have been isolated from the leaves of Annona glabra by activity-directed fractionation using the brine shrimp lethality test (BST). The structures of 1 and 2 were elucidated based on spectroscopic and chemical methods, and the absolute stereochemistries were partially determined by the advanced Mosher ester method. 1 and 2 showed selective cytotoxicities to certain human tumor cell lines, and 1 was significantly more potent although 1 and 2 differ only in the stereochemistry of their vicinal diols at C-23/24.

Annonaceous acetogenins as natural pesticides: potent toxicity against insecticide-susceptible and -resistant German cockroaches (Dictyoptera: Blattellidae).

Six compounds, representing the mono-tetrahydrofuran (THF) (gigantetrocin A, annomontacin), adjacent bis-THF (asimicin, parviflorin), and nonadjacent bis-THF (sylvaticin, bullatalicin) classes of annonaceous acetogenins, were compared with technical grades of synthetic amidinohydrazone (hydramethylnon), carbamate (propoxur, bendiocarb), organophosphate (chlorpyrifos), and pyrethroid (cypermethrin) insecticides to determine their dietary toxicities to insecticide-resistant and insecticide-susceptible strains of the German cockroach, Blattella germanica (L.). Differential susceptibility occurred among B. germanica nymphs of both strains to this variety of the acetogenins and the 5 conventional synthetic insecticides. The speed of kill (LT50) values against insecticide-susceptible and insecticide-resistant 2nd and 5th instars permitted ranking of all 11 compounds. The adjacent bis-THF acetogenins showed the highest potency among the 3 acetogenin classes. The acetogenins caused high percentages of mortality and delays in development of the 5th instars of both strains. Insecticide-susceptible nymphal development was mainly affected by gigantetrocin A and annomontacin, whereas insecticide-resistant nymphal development was mainly affected by gigantetrocin A and bullatalicin. Most tested acetogenins performed better than the conventional insecticides against both stages of both strains. No growth regulation effects were caused by any of the compounds tested. Low resistance ratios were obtained for most compounds (except chlorpyrifos). Low resistance ratios values for 2nd instars ranged from 0.9 to 2.2 with the natural acetogenins and from 1.0 to 3.8 with the synthetic compounds; the 5th instars ranged from 0.2 to 3.9 with the natural acetogenins and from 0.6 to 8.0 with the synthetic compounds. Insecticidal properties and characteristics of acetogenins and the possible use of acetogenins in baits for cockroach control are discussed.

Glacins A and B: two novel bioactive mono-tetrahydrofuran acetogenins from Annona glabra.

Two new bioactive mono-THF Annonaceous acetogenins, glacins A (1) and B (2), have been isolated, from the fractionated ethanolic extracts of the leaves of Annona glabra, directing the fractionation with the brine shrimp lethality test (BST). The structures of 1 and 2 were elucidated on the basis of spectroscopic and chemical methods, and the absolute stereochemistries were solved by preparing their respective per-Mosher ester derivatives. 1 and 2 showed potent and selective in vitro cytotoxicities among several human solid tumor cell lines.

Three new bioactive bis-adjacent THF-ring acetogenins from the bark of Annona squamosa.

Continuing work on the bioactivity-directed fractionation of the bark of Annona squamosa has resulted in the discovery of three new Annonaceous acetogenins, (2,4-cis and trans)-squamolinone (1), (2,4-cis and trans)-9-oxoasimicinone (2), and bullacin B (3). Compounds 1-3 are all adjacent bis-THF ring acetogenins with 2 representing the first bis-ring acetogenin to contain a carbonyl along its aliphatic chain. Compound 3 was selectively cytotoxic in a panel of six human tumor cell lines with a potency of nearly a million times that of adriamycin against the MCF-7 (human breast adenocarcinoma) cell line.

Mono-THF ring annonaceous acetogenins from Annona squamosa.

Continuing work on the bark of Annona squamosa Rich. (Annonaceae), directed by the brine shrimp lethality test (BST), has resulted in the isolation of three new Annonaceous acetogenins, 4-deoxyannoreticuin, cis-4-deoxyannoreticuin, and (2,4-cis and trans)-squamoxinone. The first two are additional examples of acetogenins isolated from this plant species which contain the unusual feature of an oxygen functionality at the C-9 position. They have a hydroxylated mono-THF ring with respective threo/trans/threo and threo/cis/threo relative stereochemistries. The latter compound is a ketolactone mixture which has the same relative stereochemistry around the THF ring and the same spatial relationship between the THF ring and the hydroxyl group along the aliphatic chain as 4-deoxyannoreticuin, but is two methylene units longer. Additionally, the isolated hydroxyl group is at C-11, while the THF ring starts at C-17, instead of at C-9 and C-15, respectively, as for the first two compounds. All three compounds showed moderate, but significant, cytotoxicities against a panel of six human tumor cell lines with (2,4 cis and trans)-squamoxinone showing promising selectivity against the pancreatic cell line (PACA-2).

Two new mono-tetrahydrofuran ring acetogenins, annomuricin E and muricapentocin, from the leaves of Annona muricata.

Bioactivity-directed fractionation of the leaf extract of Annona muricata L. (Annonaceae) has resulted in the isolation of two new Annonaceous acetogenins, annomuricine (1) and muricapentocin (2). Compounds 1 and 2 are monotetrahydrofuran ring acetogenins bearing two flanking hydroxyl groups; however, each has three additional hydroxyl groups. Compound 1 has an erythro 1,2-diol, and 2 has a 1,5,9-triol moiety. Both 1 and 2 showed significant cytotoxicities against six types of human tumors, with selectivities to the pancreatic carcinoma (PACA-2) and colon adenocarcinoma (HT-29) cell lines.

New bioactive triterpenoids from Melia volkensii.

Bioactivity-directed fractionation of the root bark of Melia volkensii resulted in the isolation of two new natural products, meliavolkinin (1) and melianin C (3), together with two known compounds, 1,3-diacetylvilasinin (2) and melianin B (4). Jones oxidation of 4 gave compounds 3, 23,24-diketomelianin B (5), and 16,23,24-triketomelianin B (6). The structures of the new compounds were elucidated by spectral and chemical data. Compounds 1-6 all showed marginal cytotoxicities against certain human tumor cell lines, while 5 showed selective cytotoxicities for the human prostate (PC-3) and pancreatic (PACA-2) cell lines with potencies comparable to those of adriamycin.

(2,4-cis and trans)-gigantecinone and 4-deoxygigantecin, bioactive nonadjacent bis-tetrahydrofuran annonaceous acetogenins, from Goniothalamus giganteus.

Two new acetogenins, (2,4-cis and trans)-gigantecinone (1), isolated as a mixture, and 4-deoxygigantecin (2), a known acetogenin whose absolute stereochemistry has not been determined previously, were isolated using activity-directed fractionation, from the bark of Goniothalamus giganteus. A key step in solving their absolute stereochemistries was the preparation of 1,4-diol formaldehyde acetal derivatives (1b and 2a). Using the advanced Mosher ester method and circular dichroism, the absolute stereochemistries of 1 and 2 were revealed and were found to be the same as that of gigantecin (3), which supports a common biogenetic origin. Both 1 and 1b showed potent and selective cytotoxicities against the PC-3 human prostate adenocarcinoma cell line. Against yellow fever mosquito larvae, 1 and 2 were more potent than rotenone in pesticidal activity. Longimicin C and a mixture of (2,4-cis and trans)-isoannonacin were also isolated for the first time from this species.