Rapid screening for natural lipase inhibitors from Alisma orientale combining high-performance thin-layer chromatography-bioautography with mass spectrometry

Lipase inhibitors are an attractive class of hypolipidemic compounds, which inhibit the activity of human pancreatic lipase, thereby preventing the absorption of triglycerides in vivo. As a library of promising lead compounds for drug development, traditional Chinese medicine (TCM) has gained growing attention in quick discovery and identification of enzyme inhibitors of natural-origin. The purpose of this work was to discover unknown lipase inhibitors from Alisma orientale by the activity oriented analysis method thin-layer chromatography-bioautography, then use electrospray ionization mass spectrometry technology via the elution based TLC-MS interface to identify their structures. As a result, eleven natural lipase inhibitors from Alisma orientale extracts were identified based on molecular mass and fragment ions obtained by HPTLC-MS, and further confirmed by a series of complementary means including UV spectra, ¹H NMR characteristic proton signals and polarity of compounds, eleven lipase inhibitors were tentatively assigned as triterpenoids: alisol B (m/z 495.50 [M + Na]⁺), alisol B 23-acetate (m/z 537.58 [M + Na]⁺), 11-deoxy-alisol B (m/z 479.50 [M + Na]⁺), 11-deoxy-alisol B 23-acetate (m/z 521.50 [M + Na]⁺), alisol A/epialisol A (m/z 513.50 [M + Na]⁺), 16-oxo-11-deoxy-alisol A (m/z 511.50 [M + Na]⁺), 16-oxo-alisol A (527.50 [M + Na] ⁺), alisol C (m/z 509.58 [M + Na]⁺), alisol C 23-acetate (m/z 551.50 [M + Na]⁺), alisol M 23-acetate (m/z 567.50 [M + Na]⁺), and alismanol Q/neoalisol (m/z 493.42 [M + Na]⁺). The integrated approach is an efficient method for rapid screening lipase inhibitors from complex plant extracts and provides a reasonable and favorable basis for the identification and separation of other enzymatic system and other important compounds with therapeutic values.

2-Ethoxycarbonyl-2-β-hydroxy-a-nor-cholest-5-ene-4one: Extraction, structural characterization, antimicrobial, antioxidant, anticancer and acute toxicity studies

Identification and characterization of marine natural products with antimicrobial, antioxidant activity with minimal toxicity has received much interest over the past few years. Among, Acropora formosa is one of the unexplored marine organism for the screening of natural products in marine resources. In this study, a novel steroid 2-ethoxycarbonyl-2-β-hydroxy-A-nor-cholest-5-ene-4one (ECHC) was isolated from butanol extracts of A. formosa using vacuum liquid chromatography and sequentially purified by column chromatography. The chemical structure of the compound was elucidated based on spectroscopic analysis including GC-MS, ¹H NMR and ¹³C NMR and identified as ECHC. Moreover, in vitro antioxidant activity showed that ECHC was highly scavenged the oxidative stress generative molecules. The in vitro cytotoxic activity of ECHC showed excellent activity against human breast cancer cells. Further, in vivo acute toxicity of ECHC on zebrafish Danio rerio was showed no toxicity as well as no morphological damage was observed after 21 days exposure. Histological analysis revealed that there is no apparent difference was observed between ECHC exposure and control group of D. rerio. Together, these results confirmed that ECHC has in vitro antioxidant and anticancer activity and could be developed as a potential drug against most contagious disease like cancer.

Sterol-recognition ability and membrane-disrupting activity of Ornithogalum saponin OSW-1 and usual 3-O-glycosyl saponins

OSW-1 is a structurally unique steroidal saponin isolated from the bulbs of Ornithogalum saundersiae, and has exhibited highly potent and selective cytotoxicity in tumor cell lines. This study aimed to investigate the molecular mechanism for the membrane-permeabilizing activity of OSW-1 in comparison with those of other saponins by using various spectroscopic approaches. The membrane effects and hemolytic activity of OSW-1 were markedly enhanced in the presence of membrane cholesterol. Binding affinity measurements using fluorescent cholestatrienol and solid-state NMR spectroscopy of a 3-d-cholesterol probe suggested that OSW-1 interacts with membrane cholesterol without forming large aggregates while 3-O-glycosyl saponin, digitonin, forms cholesterol-containing aggregates. The results suggest that OSW-1/cholesterol interaction is likely to cause membrane permeabilization and pore formation without destroying the whole membrane integrity, which could partly be responsible for its highly potent cell toxicity.

The Protective Effects of Alisol A 24-Acetate from Alisma canaliculatum on Ovariectomy Induced Bone Loss in Vivo

Alisma canaliculatum is a herb commonly used in traditional Korean medicine, and has been shown in scientific studies to have antitumor, diuretic hepatoprotective, and antibacterial effects. Recently, the anti-osteoclastogenesis of alisol A 24-acetate from Alisma canaliculatum was investigated in vitro. However, the influence of alisol A 24-acetate on osteoporosis in animals has not been investigated. The present study was undertaken to investigate the anti-osteoporotic effect of alisol A 24-acetate on bone mass in ovariectomized (OVX) mice and to identify the mechanism responsible for its effects. OVX mice were treated daily with 0.5 or 2 μg/g of alisol A 24-acetate for a period of six weeks. It was found that these administrations significantly suppressed osteoporosis in OVX mice and improved bone morphometric parameters. The serum estradiol, bone alkaline phosphatase levels, regulatory T/Th17 cell numbers were significantly increased by alisol A 24-acetate as compared with untreated OVX mice. In addition, TRAP activity was inhibited by alisol A 24-acetate in OVX mice. These results suggest alisol A 24-acetate effectively prevents bone loss in OVX mice, and that it can be considered a potential therapeutic for the treatment of postmenopausal osteoporosis.

Studies on chemical constituents of Ophiopogon japonicus

Two new and six known steroidal glucosides were isolated from the tuber of Ophiopogon japonicus. The new steroidal glucosides were established as (20R,25R)-26-O-β-d-glucopyranosyl-3β,26-dihydroxycholest-5-en-16,22-dioxo-3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-glucopyranoside (1) and 26-O-β-d-glucopyranosyl-(25R)-furost-5-en-3β,14α,17α,22α,26-pentaol-3-O-α-l-rhamnopyranosyl-(1 → 2)-β-d-glucopyranoside (3) on the basis of spectroscopic data as well as chemical evidence.

A new flavonone from seeds of Alpinia katsumadai and its neuroprotective effect on PC12 cells

A new flavonone, named as (2R, 3S)-pinobanksin-3-cinnamate(1), together with six known compounds, pinocem-brin (2), pinobanksin (3), 3-O-acetylpinobanksin (4), galangin (5), kumatakenin(6), and 3-methylkaempferol (7), were isolated from a 95% ethanol extract of seeds of Alpinia katsumadai through a combination of various chromatographic techniques, including silica gel and Sephadex LH-20. The structure of compound 1 was elucidated by spectroscopic data analysis. Compound 1 exhibits a potent neuroprotective effect against the corticosterone-damaged PC12 cells, which may be underlying the effect by scavenging intracellular ROS.

A new steroid with long cross-conjugation structure from the marine-derived fungus Aspergillus aculeatus

A new steroid with a long cross-conjugation structure, 15a-hydroxy-(22E, 24R)-ergosta-3, 5, 8 (14), 22-tetraen-7-one (1), was isolated from the marine-derived fungus Aspergillus aculeatus. Its structure was established by the extensive spectroscopic analyses, and its cytotoxicities against P388, HL-60, and PC-3 cell lines were measured in vitro.

[Study on constituents of the aerial parts of Pogostemon cablin]

OBJECTIVE

To investigate the chemical constituents of the aerial parts of Pogostemon cablin.

METHODS

The constituents were isolated by column chromatography over silica gel, Sephadex LH-20 and C8. Structures were identified by spectroscopic data analysis.

RESULTS

Thirteen compounds were obtained and elucidated as patchouli alcohol (1), pogostone (2), friedelin (3), epifriedelinol (4), oleanolic acid (5), methyl oleanolate (6), 5alpha-stigmast-3,6-dione (7), stigmast-4-ene-3-one (8), beta-sitosterol (9), pachypodol (10), retusin (11), (-)-guaiacylglycerol (12) and dibutyl phthalate (13).

CONCLUSION

Compounds 6, 7, 8, 12 and 13 are isolated from this genus for the first time.

Cytotoxic cholesta-1,4-dien-3-one derivatives from soft coral Nephthea sp

Five new steroids, (12β, 22R)-12-acetoxy-22-hydroxy-cholesta-1,4-dien-3-one (1), (12β, 22R)-12-hydroxy-22-acetoxy-cholesta-1, 4-dien-3-one (2), (12β, 22R)-12, 22-diacetoxy-cholesta-1, 4-dien-3-one (3), (22R)-18, 22-diacetoxy-cholesta-1, 4-dien-3-one (4), (20R, 22R)-20-hydroxy-22-acetoxy-cholesta-1, 4-dien-3-one (5), and one known steroid astrogorgol N (6), were isolated from soft coral Nephthea sp. Their structures were established by spectroscopic analysis (1D, 2D NMR, HRMS) and comparisons of their spectral data with those of related steroids. The absolute configuration at C-22 of 1 was determined to be R by Mosher's analysis. All isolated compounds exhibited cytotoxic activity against HeLa cells with IC50 values ranged from 7.51±0.22 to 18.72±0.78μg/mL.

Two new compounds from an endophytic fungus Alternaria solani

Two new secondary metabolites, named 7-dehydroxyl-zinniol (1) and 20-hydroxyl-ergosta-4,6,8(14),22-tetraen-3-one (2), were isolated from the culture of Alternaria solani, an endophytic fungal strain residing in the roots of Aconitum transsectum. Their structures were elucidated on the basis of comprehensive spectroscopic analyses including IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR. Biological activity tests indicated that compound 1 showed moderate anti-HBV activity.

[Study on the chemical constituents from Cyathea spinulosa]

OBJECTIVE

To study the chemical constituents from Cyathea spinulosa.

METHODS

Compounds were isolated by chromatographic techniques. Their structures were elucidated by spectral methods.

RESULTS

Eight compounds were isolated from the ethanol extract of Cyathea spinulosa and identified as stigmast-4-ene-3,6-dione (1), stigmast-3,6-dione (2), ergosterol (3), protocatechuic aldehyde (4), 1-O-beta-D-glucopyranosyl-(2S,3R,4E,8Z)-2-[(2-hydroxyoctadecanoyl) amido]-4,8- octadecadiene-1,3-diol (5), (2S,3S, 4R)-2-[(2'R) -2'-hydroxytetracosanoylamino]-1,3,4-octadecanetriol (6), beta-sitosterol (7), daucosterol (8).

CONCLUSION

Compounds 1-6 are isolated from this plant for the first time.

Renaissance remedies: Antiplasmodial protostane triterpenoids from Alisma plantago-aquatica L. (Alismataceae)

AIM OF THE STUDY

In a preliminary screen of extracts from plants used as antimalarial remedies used in Europe in the 16th and 17th, the ethyl acetate extract of Alisma plantago-aquatica L. (Alismataceae) was active against Plasmodium falciparum K1 strain with 77% growth inhibition at 4.9μg/ml. The aim of this study was to isolate and identify the substances responsible for this antiplasmodial activity.

MATERIALS AND METHODS

With HPLC-based activity profiling in combination with HPLC hyphenated methods (HPLC-PDA, -MSn, HR-MS, and off-line microprobe NMR) the activity was assigned to time windows, and the substances contained therein were characterised chemically. The active compounds were isolated with semi-preparative HPLC and structures were elucidated with high resolution mass spectrometry, and 1D and 2D NMR spectroscopy.

RESULTS

Four compounds were isolated and identified as protostane triterpenoids alisol A, alisol B 11-monoacetate, alisol B 23-monoacetate, and alisol G. Their IC(50)s against Plasmodium falciparum ranged from 5.4 to 13.8μM.

CONCLUSIONS

This is the first report of antiplasmodial activity from protostanes triterpenoids, and the first result of our ongoing project of screening for antiprotozoal natural products from remedies used in European renaissance medicine.

[Sterols of marine bryozoan Bugula neritina from the South China Sea]

OBJECTIVE

To study the sterol constituents of Bugula neritina from the South China Sea.

METHODS

The alcohol extract of Bugula neritina was purified by silica gel column and Sephadex LH-20 column chromatography, and structures of the isolated compounds were identified by spectroscopic analysis and comparison with those of literatures.

RESULTS

Ten sterols were isolated and identified from the petroleum ether fraction of alcohol extract of B. neritina L.:Cholest-4-en-3-one(I); cholesterol(II);3beta,5alpha,9alpha-trihydroxy-(22E,24R)-ergosta-7,22-dien-6-one(III); 24-methyl-5alpha-cholesta-7,22-diene-3beta,5,6beta-triol(IV); 3beta-Hydroxy-7-methoxy-Cholesta-5-en(V);5alpha, 8alpha-epidioxy-(22E,24R)-ergosta-6, 22-dien-3beta-ol(VI); 3beta-hydroxycholest-5-en-7-one (VII); and 6beta-hydroxy-cholest-4-en-3-one(VIII); Cholesta-5-ene-3beta,7beta-diol(IX); Cholesta-5,22(E)-dien-3beta,7alpha-diol(X).

CONCLUSION

Compounds IV-X were isolated from Bugula neritina for the first time.

[Studies on the chemical constituents from petroleum ether portion of Abelmoschus esculentus]

OBJECTIVE

To study the chemical constituents of Abelmoschus esculentus.

METHODS

The chemical constituents were isolated and purified by chromatography on silica gel and recrystallization. The chemical structures were elucidated on the basis of physicochemical properties and spectral date.

RESULTS

Twelve compounds were isolated and identified as 9,19-23 (Z)-cycloart-23-en-3beta, 25-diol(1), ergost-7,22-diene-3beta,5alpha,6beta-triol(2),5alpha, 6alpha-epoxyergost-8(14), 22-dien-3beta, 7alpha-diol(3), 5alpha,8alpha-epidioxyergost-22-en-3beta-ol(4), stigmast-5-ene-3beta,7alpha-diol(5), stigmast-5, 22-diene-3beta,7alpha-diol(6), stigmast-4-en-3beta,6beta-diol(7), stigmast-4,22-diene-3beta,6beta-diol(8), stigmast-4-ene-3, 6-dione(9), stigmast-4-ene-3-one (10),beta-sitosterol(11), daucosterol(12).

CONCLUSION

Compounds 1-10 are obtained from the plant for the first time and also from the genu for the first time.

Anti-inflammatory and membrane-stabilizing stigmastane steroids from Alchornea floribunda leaves

Alchornea floribunda (Euphorbiaceae) leaves are widely used in African ethnomedicine for the management of acute and chronic inflammatory disorders. In the present study, bioactivity-guided fractionation led to the isolation of two known (1 and 3) and one new (2) stigmastane steroids from the hexane extract of Alchornea floribunda leaves. The anti-inflammatory activities of these compounds were evaluated using IN VITRO and IN VIVO animal models. The compounds 1, 2, and 3 at 50 and 100 microg/ear significantly (p < 0.05) inhibited xylene-induced ear edema in mice in a dose-dependent manner. The topical anti-inflammatory effect of 1 and 2 are significantly (p < 0.05) higher than that of indomethacin and prednisolone. At 20 mg/kg (i. p.), all the compounds significantly (p < 0.05) inhibited acute inflammation induced by subplantar injection of egg albumen in rats. Compound 1 exhibited an anti-inflammatory effect (50.9 % edema inhibition) comparable (p < 0.05) to that of prednisolone (48.0 % edema inhibition) at 3 h. Compounds 1, 2, and 3 (50 microg/mL) significantly (p < 0.05) inhibited heat-induced haemolysis of human erythrocytes in vitro, but had no effect on hypotonicity-induced hemolysis. The compounds were elucidated as (24R)-5alpha-stigmast-3,6-dione ( 1), 5alpha-stigmast - 23-ene-3,6-dione ( 2), and 3beta-hydroxy-5alpha-stigmast-24-ene ( 3) by spectral analysis. The results of this study show that these compounds may, in part, account for the anti-inflammatory effect of Alchornea floribunda leaves. This is the first report on the isolation and structure elucidation of these anti-inflammatory steroids from Alchornea floribunda leaves.

[Study on the chemical constituents of Humulus scandens]

OBJECTIVE

To study the chemical constituents of Humulus scandens.

METHODS

The compounds were isolated by column chromatography on silica gel and Sephadex LH-20. The structures were identified by means of IR, 1H-NMR,13C-NMR and MS analyses.

RESULTS

Seven compounds were isolated and identified as friedelanone (I), cis-asarone (II), epifriedelanol (III), stigmasta-4-ene-3,6-dione (IV), gamma-sitosterol (V), n-hexadecanoic acid (VI), and linoleic acid (VII), respectively.

CONCLUSION

All compounds are isolated from this species for the first time and compounds I - V are obtained from this genus for the first time.

Steroids and alkaloids from the South China Sea sponge Axinella sp

A new steroid 24beta-methylcholasta-1,8,14,22,25-penten-3-one-5alpha-ol (1) and a new alkaloid 1-(1H-indol-3-yl)-2,3-dihydroxy-5-methyl-hexane (2), together with four known compounds, were isolated from the EtOH extract of the South China Sea sponge Axinella sp. The structures of 1 and 2 were determined on the basis of extensive spectroscopic analysis, including 1D and 2D NMR spectral data.

[Studies on the chemical constituents of ethyl acetate extract from the roots of Actinidia chrysantha]

OBJECTIVE

To study the chemical constituents of ethyl acetate extract from the roots of Actinidia chrysantha.

METHODS

Chromatographic methods were used to isolate the compounds from ethyl acetate extract from the roots of Actinidia chrysantha and chemical and spectral methods were used to elucidate the structures of the isolated compounds.

RESULTS

Five compounds were identified as stigmast-3, 6-dione (I), beta-sitosterol (II), ursolicacid (III), beta-daucosterol (IV), 2alpha, 3beta, 23-triol-12-en-28-ursolic acid (V).

CONCLUSION

Those compounds are obtained from the plant for the first time.

(1)H and (13)C NMR assignments for two new steroids from the coral Chromonephthea sp

Two new steroids isolated from EtOH extracts of the South China Sea soft coral Chromonephthea sp. were identified. One-dimensional (1D) and two-dimensional (2D) NMR experiments including COSY, HSQC, HMBC and NOESY were used for the determination of their structure.

Chemical constituents in roots of Osbeckia opipara

OBJECTIVE

To study the chemical constituents of the roots of Osbeckia opipara.

METHOD

Repeated column chromatography over silica gel, RP-18 and Sephadex LH-20, and preparative thin layer chromatography(PTLC) were used to isolate the compounds, whose structures were determined by spectroscopic methods by direct comparing spectral data with those reported references.

RESULT

From the MeOH extract of the roots O. opipara, twelve compounds were isolated and identified as follows: lasiodiplodin (1) , de-O-methyllasiodiplodin (2), 2, 3- dihydro-2-hydroxy-2, 4-dimethyl-5-trans-propenylfuran-3-one (3), integracin (4), 5alpha, 8alpha-epidioxy-(22E, 24R)-ergosta-6, 22-dien-3beta-ol (5), 3, 3', 4'-tri-O-methylellagic acid (6), 5-hydroxymethyl furaldehyde (7), vomifolio (8) , betulintic acid (9), 2alpha-hydroxyursolic acid (10), (24R)-stigmast-4-ene-3-one (11), and eugenitin (12).

CONCLUSION

Compounds 1-12 were isolated from O. opipara for the first time.

[Chemical constituents from involatile moiety of Pogostemon cablin]

OBJECTIVE

To study the chemical constituents of involatile moiety of Pogostemon cablin.

METHOD

Compounds were isolated and purified by repeated column chromatography, and their structures were elucidated by spectroscopic analysis.

RESULT

Nine compounds have been isolated and identified: epifriedelinol (1), 5-hydroxymethol-2-furfural (2), succinic acid (3), beta-sitosterol (4), daucosterol (5), crenatoside (6), 3'''-O-methylcrenatoside (7), isocrenatoside (8), and apigenin-7-O-beta-D-(6"-p-coumaryl)-glucoside (9).

CONCLUSION

Compounds 2, 3, 6-8 were isolated from Pogostemon genus for the first time.

[Study on the chemical constituents of liposoluble steroidal and triterpenoid compounds from the stem and bark of Macaranga hemsleyana]

OBJECTIVE

to research the chemical constituents of the liposoluble compounds from the stem and bark of Macaranga hemsleyana Pax & Hoffm.

METHODS

Five compounds were obtained by silica chromatography and preparative TLC from the stem and bark of Macaranga hemsleyana Pax & Hoffm., and the chemical structures of these compounds were identified by modern spectroscopy as well as physico-chemical analysis.

RESULTS

These compounds were identified to be beta-Sitosterol (1), Stigmast-4-en-3-one (2), Stigmast-4-en-3,6-dione (3), 3beta-O-acetyl aleuritolic acid (4) and Canophyllol (5).

CONCLUSION

The liposoluble fractions of Macaranga hemsleyana Pax & Hoffm. are mainly steroidal and triterpenoid compounds.

[Studies on chemical constituents of marine bryozoan Bugula neritina L]

Seven compounds were isolated from the marine bryozoan Bugula neritina L. Their chemical structures were identified by NMR and MS spectroscopies as follows: cholesterol (I), cholest-4-en-3-one (II), cholesteryl myristate (III), 3beta,5alpha,9alpha-trihydrox-y-(22E,24R)-ergosta-,22-dien-6-one (IV), 3beta,5alpha,6beta-trihydroxy-(22E,24R)-ergosta-7,22-dien (V), uracil (VI), thymine (VII). Compounds II-VII were isolated from Bugula neritina L. for the first time.

[Studies on chemical constituents of Cynanchum forrestii]

OBJECTIVE

To study the chemical constituents of Cynanchum forrestii.

METHOD

Chromatographic techniques were applied to isolated chemical constituents. The structures were identified on the basis of physico-chemical constants and spectroscopic data.

RESULT

Eight compounds were isolated from the 95% ethanol extract of the roots of C. forrestii and elucidated as ( + ) -5'-methoxyisolariciresinol 3a-O-beta-D-glucopyranoside (1), hexahydroxycholest-7-en-6-one (2), tylophorinidine (3), sucrose (4), palmitic acid (5), beta-sitosterol (6), daucosterol (7), nonanedioic acid (8).

CONCLUSION

Compounds 1-3 from this genus, and compounds 4-8 from the plant were obtained for the first time.

[Studies on chemical constituents in the mycelia from fermented culture of Flammulina velutipes]

OBJECTIVE

To study the chemical constituents from the mycelia of Flammulina velutipes.

METHOD

The compounds were isolated with silica gel column chromatography and their structures were elucidated on the basis of chemical evidences and spectral analysis (IR, EI-MS, 1H-NMR, 13C-NMR).

RESULT

Five compounds were identified as 5alpha,8alpha-epidioxy-(22E,24R)-ergost-6,22-dien-3beta-ol (1), ergosta-4,6,8(14),22-tetraen-3-one (2), sterpuric acid (3), mannitol (4), ribitol (5).

CONCLUSION

The compounds (2)-(5) were isolated for the first time from the mycelia of Flammulina velutipes.

[Studies on the chemical constituents in herb of Ranunculus sceleratus]

OBJECTIVE

To isolate and determine the chemical constituents from Ranunculus sceleratus.

METHOD

Six compounds were isolated and purified by extraction and different kinds of column chromatography. The structures were determined on the basis of extensive spectral analysis such as EI-MS, 1H-NMR, 13C-NMR, DEPT and NOEDS.

RESULT

The structures were elucidated as stigmasta-4-ene-3,6-dione I, stigmasterol II, isoscopoletin III, scoparone IV, protocatechuic aldehyde V and protocatechuic acid VI, respectively.

CONCLUSION

Compound I, III, IV, V and VI were isolated from R. genus for the first time.

Two novel steroids from Euphorbia officinarum latex

Two novel steroids, 3beta,7alpha-dihydroxy-4alpha,14alpha-dimethyl-5alpha-cholest-8-en-11-one (2) and 3beta,7beta-dihydroxy-4alpha,14alpha-dimethyl-5alpha-cholest-8-en-11-one (3) were isolated from the latex of Euphorbia officinarum. Their structures were established on the basis of NMR and MS studies.

Quality evaluation of alismatis rhizoma by high performance liquid chromatography

The quality of Alismatis Rhizoma was evaluated by reversed-phase high performance liquid chromatographic method. Alisol B 23-acetate was used as a standard marker for evaluation. This component was fully separated from the other components in the plant extracts on a ODS column. Identification of alisol B 23-acetate was carried out by comparing the LC/MS spectrum of separated peak from the extract with that of standard. Alisol B 23-acetate contents in Alismatis Rhizoma obtained from several herbal markets were varied from 0.15% to 0.56%.

Flavanone glycosides from Miconia trailii

Assay-guided fractionation of the ethanol extract of the twigs and leaves of Miconia trailii yielded two new flavanone glycosides, matteucinol 7-O-alpha-l-arabinopyranosyl(1-->6)-beta-d-glucopyranoside (miconioside A, 1) and farrerol 7-O-beta-d-apiofuranosyl(1-->6)-beta-d-glucopyranoside (miconioside B, 2), along with the known compounds matteucinol 7-O-beta-d-apiofuranosyl(1-->6)-beta-d-glucopyranoside (3), matteucinol (4), 2alpha,3beta,19alpha-trihydroxyolean-12-ene-24,28-dioic acid (bartogenic acid, 5), 2alpha,3beta,23-trihydroxyolean-12-ene-28-oic acid (arjunolic acid, 6), 2alpha,3alpha,19alpha, 23-tetrahydroxyurs-12-ene-28-oic acid (myrianthic acid, 7), and stigmast-4-ene-3,6-dione (8). The structures of 1-8 were elucidated by spectroscopic methods, including 2D NMR.

Antifungal steroidal glycosides from the patagonian starfish anasteriasminuta: structure-activity correlations

Two new sulfated steroidal hexaglycosides, anasterosides A (2) and B (3), along with the known versicoside A (1) have been isolated from the Patagonian starfish Anasterias minuta. Their structures have been elucidated by spectroscopic analysis (NMR and FABMS) and chemical transformations. Compounds 1 and 2 and the synthetic pentaglycoside 1b derived from versicoside A showed antifungal activity against the plant pathogenic fungus Cladosporium cucumerinum. Desulfation of hexaglycoside 1 rendered a totally inactive saponin.

Cytotoxic triterpenoides from Alismatis Rhizoma

Four prostane-type triterpenes were isolated from a methanol extract of Alismatis Rhizoma by bioassay-guided isolation using in vitro cytotoxic assay. The compounds were identified as alisol B 23-acetate (1), alisol C 23-acetate (2), alisol B (3), alisol A 24-acetate (4) by spectroscopic methods. Amongst the compounds, alisol B (3) showed significant cytotoxicity against SK-OV3, B16-F10, and HT1080 cancer cell lines with ED50 values of 7.5, 7.5, 4.9 microg/ml, respectively.

Furodysin lactone and pyrodysinoic acid, new sesquiterpenes from a Philippines Dysidea species

Chemical investigation of a Dysidea sponge, collected at Siquijor, Philippines, has afforded two new sesquiterpenoid metabolites, which we have termed furodysin lactone (1) and pyrodysinoic acid (2). The known 3,6,11-trihydroxy-9,11-secoergostane-7,24(28)-dien-9-one (3) was also encountered. Structure elucidation of the isolated metabolites involved high-field 2-D NMR spectroscopy including (1)H-(1)H COSY, HSQC, and HMBC.

Two new 26,27-cyclosterols from the marine sponge Strongylophora corticata

Two novel steroids with a cyclopropane ring at C-25 and C-26, 7-oxopetrosterol (1) and 7alpha-hydroxypetrosterol (2), along with two known compounds, petrosterol (3) and 23,24-dihydrocalysterol (4), have been isolated from the Japanese marine sponge Strongylophora corticata. The structures of 1 and 2 were determined as 26, 27-cyclo-24,27-dimethyl-3beta-hydroxycholest-5-en-7-one and 26, 27-cyclo-24,27-dimethylcholest-5-en-3beta,7alpha-diol on the basis of spectroscopic investigations.

[Isolation and identification of three steroid compounds from Mauremys mutics plastron]

OBJECTIVE

To investigate the steroids components from extract of Mauremys mutics.

METHOD

The steroid compounds were isolated by using vacuum liquid chromatography and PTLC. The structures of three compounds were determined by spectral, chromatographic and chemical analysis.

RESULTS

Three steroids were isolated from M. mutics and identified as cholesterol, elcosenoic acid cholesterol ester, cholester-4-ene-3-one.

CONCLUSION

All the three compounds were isolated from M. mutics for the first time.

Ecdysteroids from the caribbean sponge Iotrochota birotulata

The sterol composition of the Caribbean sponge Iotrochota birotulata was investigated. Structure of a new ecdysteroid 2beta,3beta,14alpha, 20beta-tetrahydroxy-22alpha-(2-hydroxyacetiloxy)-5b eta-colest-7-en-6- one (1) was assigned on the basis of spectroscopic and chemical evidence and molecular mechanics calculations. Isolation of the widespread ecdysteroids 2-5 is also reported.

In vitro inducible nitric oxide synthesis inhibitors from Alismatis Rhizoma

Bioassay-guided fractionation of an aqueous extract of Alismatis Rhizoma has furnished two inducible nitric oxide synthase (iNOS) inhibitory compounds, alismol (1) and alisol B monoacetate (2), together with an inactive triterpene, alisol C monoacetate (3). Compounds 1 and 2 inhibited nitric oxide (NO) synthesis in a dose-dependent manner in murine macrophage-like RAW 264.7 cells stimulated with interferon-gamma (IFN-gamma) plus lipopolysaccharide (LPS). The inhibitory effects of 1 and 2 on NO synthesis were partly due to suppression of iNOS mRNA expression as determined by Northern blotting.

Constituents and bioactive principles of Polygonum chinensis

Isolation and characterization of the chemical constituents of Polygonum chinensis L. gave the new 25R-spirost-4-ene-3,12-dione. The known compounds stigmast-4-ene-3,6-dione, stigmastane-3,6-dione, hecogenin and aurantiamide acetate were also isolated from for the first time from this species. Their anti-inflammatory and anti-allergic properties are described.

Cholesterol and its derivatives, are the principal steroids isolated from the leech species Hirudo medicinalis

Steroids were isolated from the blood-sucking leech species Hirudo medicinalis and their structure was studied with one- and two-dimensional NMR spectroscopy (DQF-COSY and HMQC), GC-MS and ESI-MS spectrometry. Fractionating leech lipid using silicic acid chromatography led to the isolation of cholesterol in an early chloroform-eluted peak. Only minor traces of cholest-4-en-3-one, 4 beta-methylcholesterol, and sitosterol were present. The subsequent acetone-eluted fraction contained steroidtriols that were further purified by preparative TLC; these included cholest-7-ene-3,5,6 triol, cholest-4,7-diene-3,6,15 triol and to a lesser amount, cholestane-3,5,6 triol. A developmental study on cholesterol content in the leech showed that it is also the principal steroid in embryonic and freshly hatched leeches prior to feeding. The abundance of cholesterol, comprising approximately 5% of the total leech lipid, suggests that H. medicinalis, a blood sucking leech, has adapted itself fully to its mammalian host in terms of its steroid content. It remains to be seen whether lipids are directly transferred from the host to the parasite or whether leeches have evolved mechanisms to synthesize their own steroids.

The effect of 9,11-secosterol, a newly discovered compound from the soft coral Gersemia fruticosa, on the growth and cell cycle progression of various tumor cells in culture

A new 9,11-secosterol, 24-nor-9,11-seco-11-acetoxy-3 beta,6 alpha-dihydroxycholest-7,22(E)-dien-9-one, was found to exhibit growth inhibitory (IC50 below 10 microM) and cytotoxic activities against human leukemia K562, human cervical cancer HeLa, and Ehrlich ascites tumor cells in vitro. The cytostatic concentrations of the compound generally caused the G2/M block in the cell cycle progression, but differences between the three tumor cell lines in the events leading to cell death were remarkable. While inhibiting cell proliferation, 9,11-secosterol caused accumulation of HeLa and K562 cells in the metaphase of mitosis. So, abnormal mitosis can play an important role in the cytotoxicity of 9,11-secosterol in these cell lines. In the Ehrlich ascites tumor cell line the increasing concentrations of the drug (up to 40 microM) did not cause an immediate cell killing. Instead, due to continued DNA synthesis without entry into mitosis, cells with high DNA ploidy were produced. It was shown that the cytoskeletal systems such as microtubules and microfilaments were not damaged by the action of 9,11-secosterol. Further studies are necessary to elucidate the mechanism of the cytotoxic effect of 9,11-secosterol.

Bacterial cholesterol oxidases are able to act as flavoprotein-linked ketosteroid monooxygenases that catalyse the hydroxylation of cholesterol to 4-cholesten-6-ol-3-one

A new metabolite of cholesterol was found in reaction mixtures containing cholesterol or 4-cholesten-3-one as a substrate and extra- or intracellular protein extracts from recombinant Streptomyces lividans and Escherichia coli strains carrying cloned DNA fragments of Streptomyces sp. SA-COO, the producer of Streptomyces cholesterol oxidase. The new metabolite was identified as 4-cholesten-6-ol-3-one based on comparisons of its high-performance liquid chromatography, gas chromatography/mass spectrometry, infrared and proton-nuclear magnetic resonance spectra with those of an authentic standard. Genetic analyses showed that the enzyme responsible for the production of 4-cholesten-6-ol-3-one is cholesterol oxidase encoded by the choA gene. Commercially purified cholesterol oxidase (EC 1.1.3.6.) of a Streptomyces sp., as well as of Brevibacterium sterolicum and a Pseudomonas sp., and a highly purified recombinant Streptomyces cholesterol oxidase were also able to catalyse the 6-hydroxylation reaction. Hydrogen peroxide accumulating in the reaction mixtures as a consequence of the 3 beta-hydroxysteroid oxidase activity of the enzyme was shown to have no role in the formation of the 6-hydroxylated derivative. We propose a possible scheme of a branched reaction pathway for the concurrent formation of 4-cholesten-3-one and 4-cholesten-6-ol-3-one by cholesterol oxidase, and the observed differences in the rate of formation of the 6-hydroxy-ketosteroid by the enzymes of different bacterial sources are also discussed.

Two new 9,11-secosterols from the marine sponge Spongia officinalis. Synthesis of 9,11-seco-3 beta,6 alpha,11-trihydroxy-5 alpha-cholest-7-en-9-one

Two new 9,11-secosterol, 9,11-seco-3 beta,6 alpha,11-trihydroxy-5 alpha-cholest-7-en-9-one (2) and 9,11-seco-3 beta,6 alpha,11-trihydroxy-24- methylene-5 alpha-cholest-7-en-9-one (3), have been isolated from the marine sponge Spongia officinalis and their structures elucidated by analysis of spectral data including 1H nuclear magnetic resonance correlation spectroscopy (COSY) experiments. Partial synthesis of 2 starting from 3 beta,6 alpha-dihydroxy-9-oxo-9,11-seco-5 alpha-cholest-7-en-11- al (1) confirmed the structure assignment.

Three new 7-keto sterols from the Mediterranean sponge Clathrina clathrus

The CHCl3 extract of the Mediterranean sponge Clathrina clathrus was shown to contain three new sterols: (22 E)-3 beta-hydroxycholesta-5,8,22-trien-7-one (1), (22 E, 24 xi)-3 beta-hydroxy-24-methylcholesta-5,8,22-trien-7-one (2), and (22 E, 24 xi)-3 beta-hydroxy-24-ethylcholesta-5,8,22-trien-7-one (3), whose structures were elucidated on the basis of physico-chemical evidence.

Inhibitors of sterol synthesis. Reverse phase high performance liquid chromatography for the separation of cholesterol, 5 alpha-cholest-8(14)-en-3 beta-ol-15-one, and their fatty acid esters

A relatively simple and rapid method was required for the separation of 5 alpha-cholest-8(14)-en-3 beta-ol-15-one, a potent inhibitor of sterol synthesis, from its major metabolites. Conditions have been determined which permit the resolution of the 15-ketosterol and cholesterol and fatty acid esters of the two sterols by reverse phase high performance chromatography. This methodology also permits the resolution of the major esters of the 15-ketosterol and of cholesterol.

Characterization of two steroidal ketones and two isoprenoid alcohols in dairy products

Two steroidal ketones, delta-4-cholesten-3-one and delta-3,-5-cholestadiene-7-one, were isolated and identified for the first time in anhydrous milk fat and in nonfat dry milk. Together with these, two isoprenoid alcohols, phytol and dihydrophytol, were identified in anhydrous milk fat. Their identities were established on the basis of chromatographic and mass spectral data and confirmed by comparison with authentic materials.