New antifungal and cytotoxic steroidal saponins from the bulbs of an elephant garlic mutant

Saponins in bulbs of a mutant of elephant garlic were investigated, and three new steroidal saponins named yayoisaponins A-C were obtained together with the known dioscin and aginoside. Their structures, including the relative stereochemistry, were elucidated by spectral data interpretation, while the absolute stereochemistry of the sugar moieties was assigned on the basis of a chiral gas chromatographic analysis of the acid hydrolysates. Yayoisaponins A-C and aginoside exhibited not only in vitro cytotoxicity against P388 cells at 2.1 micrograms/ml, but also antifungal activity against Mortierella ramanniana at 10 micrograms/disk.     

DNA-damaging steroidal alkaloids from Eclipta alba from the suriname rainforest1

Bioassay-guided fractionation of the MeOH extract of Eclipta alba using three yeast strains (1138, 1140, and 1353) resulted in the isolation of eight bioactive steroidal alkaloids (1-8), six of which are reported for the first time from nature. The major alkaloid was identified as (20S)(25S)-22,26-imino-cholesta-5,22(N)-dien-3beta-ol (verazine, 3), while the new alkaloids were identified as 20-epi-3-dehydroxy-3-oxo-5,6-dihydro-4,5-dehydroverazine (1), ecliptalbine [(20R)-20-pyridyl-cholesta-5-ene-3beta,23-diol] (4), (20R)-4beta-hydroxyverazine (5), 4beta-hydroxyverazine (6), (20R)-25beta-hydroxyverazine (7), and 25beta-hydroxyverazine (8). Ecliptalbine (4), in which the 22,26-imino ring of verazine was replaced by a 3-hydroxypyridine moiety, had comparable bioactivity to verazine in these assays, while a second alkaloid (8) showed good activity against Candida albicans. All the alkaloids showed weak cytotoxicity against the M-109 cell line.     

Acylated C-21 steroidal bisdesmosidic glycosides from Caraluma umbellata

From the whole plant of Caraluma umbellata, three new C-21 steroidal glycosides, named as carumbellosides III-V, were isolated and their structures elucidated by extensive spectroscopic experiments, devoid of any derivatisation, as caralumagenin 3-O-beta-D-glucopyranosyl(1-->4)-beta-D-digitalopyranoside-20-O-be ta- D-glucopyranoside, caralumagenin 3-O-beta-D-glucopyranosy(1-->4)- beta-D-digitalopyranoside-20-O-(2-O- benzoyl)-beta-D-glucopyranoside and caralumagenin 3-O-[6-O-benzoyl-beta-D-glucopyranosyl(1-->4)]-beta-D- digitalopyranoside-20-O-(2-O-benzoyl)-beta-D-glucopyranoside. The determination of the absolute configuration of the aglycone as (20 R), the conformations of the sugars and the unambiguous assignments of their NMR spectroscopic signals were achieved by a combination of 2D-NMR techniques. The isolates were devoid of significant cytotoxity in the UIC human cancer cell panel.     

Solakhasoside, a novel steroidal saponin from Solanum khasianum

Solakhasoside (1), a novel steroidal saponin, was isolated from the fruit of Solanum khasianum. Its structure was determined as (23S, 25S)-spirot-5-en-3beta,17alpha, 23-triol-3-O-[alpha-L-rhamnopyranosyl-(1-->2)[beta-D-xylopyranosyl-(1 -->3)]-beta-D-galactopyranoside] (1) by spectroscopic analysis.     

Nutritive value of Geotricum candidum yeast prepared from decaying fruits in Egypt

Quantitative histology of thin, nondecalcified sections was performed on sequential bone biopsy specimens from five patients undergoing long-term hemodialysis and treated with calcifediol (25-hydroxycholecalciferol) for periods of three to nine months. With increase of intestinal absorption of calcium and decline of circulating immunoreactive parathyroid hormone and alkaline phosphatase, the bones of each patient exhibited striking histological improvement. The group as a whole showed statistically significant decreases in osteoclast number and in the percentages of osteoid surface covered by active osteoblasts. Marrow fibrosis was either eliminated or strikingly decreased in each patient. Osteoid volume significantly declined in four of five patients. In patients with osteitis fibrosa as the predominant histological lesion, calcifediol therapy resulted in decreased calcification front activity. Increased activity was the result when osteomalacia predominated.     

Chemical constituents from the bark of Hibiscus syriacus L

Seven constituents (I-VII) were isolated from the bark of Hibiscus syriacus and identified as nonanedioic acid (I), suberic acid (II), 1-octarcosanol (III), beta-sitosterol (IV), 1,22-docosanediol (V), betulin (VI) and erythrotriol (VII). VII was obtained from the plant for the first time, I, II, III and VI were isolated from Malvaceae plants for the first time.     

Complete amino acid sequence of chitinase-a from bulbs of gladiolus (Gladiolus gandavensis)

The complete amino acid sequence of gladiolus bulb chitinase-a (GBC-a) was determined. First the tryptic peptides from GBC-a after it was reduced and S-carboxymethylated were sequenced and then the peptides were further studied by chemical cleavage of the enzyme. GBC-a consisted of 274 amino acid residues and had a molecular mass of 30,714 Da. Two consensus sequences essential for chitinase activity by plant class III chitinases were conserved in GBC-a, although its sequence similarity with plant class III chitinases was less than 20%. Sequence comparison of GBC-a with sequences of other proteins in a protein identification resource (PIR) showed that the GBC-a sequence was 33% similar to that of narbonin, a seed storage 2S globulin from narbon beans.     

Chemical constituents from the aerial part of Epimedium brevicornum Maxim

Six flavonoids were isolated from the aerial part of Epimedium brevicornum and identified as baohuo side I, 2"' O-rhamnosyl icariside II, sagittatoside B, baohuoside II, ikarisoside F and ikarisoside C by means of UV, IR, 1H-NMR, 13C-NMR and FAB-MS spectral analysis, they were isolated from this plant for the first time.     

Studies on the chemical constituents of seed from Nigella glandulifera

Seven compounds were isolated from the seed of Nigella glandulifera. Their structures were identified as kaempferol-3-O-beta-D-galactopyranosyl (1-->3)-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranoside (N-I), 2-O-[alpha-D-galactopyranosyl (1-->4)-beta-D-glucopyranosyl]-beta-D-fructofuranoside (N-II), N, N-dimethyl-1, 2-dimethoxy-10, 11-dihydric aporphine quaternary ammonium chloride (N-III), 3-O-[beta-D-xylo-pyranosyl (1-->3)-alpha-L-rhamnopyranosyl (1-->2)-alpha-L-arabinopyranosyl]- 28-O -[alpha-L-rhamnopyranosyl (1-->4)-beta-D-glucopyranosyl (1-->6) beta-D-glucopyranosyl]-hederagenin (N-IV), sucrose(N-V), beta-sitosterol(N-VI) and cyclolandenol(N-VII). Compounds N-I and N-II are new compounds, named nigeglanoside and nigeglanose, respectively. Apart from ten fatty acids in its oil have also been analysed. It is the first time for the study on chemical constituents of the seed of Nigella glandulifera.     

Complete amino acid sequences of chitinase-1 and -2 from bulbs of genus Tulipa

The complete amino acid sequences of tulip bulb chitinase-1 and -2 (TBC-1 and -2) were determined. The sequences of the TBC-1 and TBC-2 were solved by analysis of peptides derived by enzymatic digestions as well as by chemical cleavages with cyanogen bromide (CNBr), o-iodosobenzoic acid, and hydroxylamine. TBC-1 and TBC-2 both consisted of 275 amino acid residues and had molecular masses of 30,825 and 30,863, respectively. They shared 247 identical residues, that is 90% identity. Comparison of their sequences with that of gladiolus bulb class IIIb chitinase-a (GBC-a) showed that 63% of the residues of both TBC-1 and TBC-2 are identical to that of GBC-a. From these results, it was seen that TBC-1 and -2 are class IIIb chitinases. The characteristic difference in specific activity between TBC-1 and -2 was also discussed on the basis of their amino acid sequences.     

New steroidal anti-inflammatory antedrugs bind to macrophage glucocorticoid receptors and inhibit nitric oxide generation

In continuing efforts to synthesize potent, anti-inflammatory steroids devoid of systemic side effects, methyl 9 alpha-fluoro-11 beta,17 alpha,21-trihydroxy-3,20-dioxo-pregna-1,4-diene-16 alpha-carboxylate (FP16CM) and its 21-acetate derivative (FP16CMAc) were recently synthesized and screened in animal models of inflammation. The compounds have now been assessed for high-affinity glucocorticoid receptor binding and glucocorticoid-mediated inhibition of nitric oxide (NO) generation in an in vitro RAW 264.7 macrophage cell culture system. Relative potencies for glucocorticoid receptor binding were 1, 1.7, and 2.4 for prednisone (P) (IC50 = 287 nM), FP16CM, and FP16CMAc, respectively. Concomitant relative potencies for inhibition of NO generation by macrophages stimulated with lipopolysaccharide were 1, 0.92 and 1.9 for P (IC50 = 126 nM), FP16CM, and FP16CMAc, respectively. Collectively, results suggest that the novel antedrugs are active anti-inflammatory agents. The 9 alpha-fluoro and 21-acetate substituent may contribute to enhanced topical potency, increased receptor binding affinity and inhibitory effects on NO generation. Inhibition of vasoactive NO may be one anti-inflammatory action of the steroidal antedrugs in vivo. Collectively, results suggest that these agents may be useful for topical application in allergic/inflammatory diseases.     

Anti-platelet aggregation constituents from Formosan Toddalia asiatica

Examination on the wood of Formosan Toddalia asiatica led to the isolation of 30 compounds, including coumarins, alkaloids, a benzoquinone and an amine. Among the isolates, (+/-)-toddanin and (-)-isocoreximine are new compounds, while cyclohexylamine was isolated for the first time from nature. The structures of the compounds were elucidated from spectroscopic data and chemical evidence. Bioassay-guided fractionation led to the isolation of seven compounds showing strong anti-platelet aggregation activity in vitro.     

Oxidation of corticosteroids to steroidal carboxylic acids by an enzyme preparation from hamster liver

Enzyme activity which catalyzes the oxidation of 11-deoxycorticosterone to 21-oic acids accompanies the "detritiating" enzyme (isomerase) of hamster liver recently isolated by Martin, K. O., et al. ((1977) Biochemistry 16 (preceding paper in this issue)). The metabolites isolated were 20alpha- and 20beta-hydroxy-3-oxo-pregn-4-en-21-oic acid and 3,20-dioxo-pregn-4-en-21-oic acid. When 21-hydroxy[4-14C, 21-3H]pregn-4-en-3,20-dione was the substrate, about half of the tritium was retained in position 20 of the hydroxy acids. The system which catalyzes the conversion of the ketol side chain of corticosteroids to acid metabolites appears to be a cluster of closely related enzymes. As a result of these studies, we believe that the hamster liver enzyme preparation provides a useful model system for studies on the biosynthesis of acid metabolites of the corticosteroids in man.     

Activity-dependent regulation of dopamine content in the olfactory bulbs of naris-occluded rats

Several lines of evidence strongly suggest that reduced olfactory nerve activity results in decreased bulb dopamine content. In the present study, high performance liquid chromatography with electrochemical detection was used to assess catecholamine levels in bulbs from postnatal day 60 rats that had undergone either unilateral naris cautery or a sham surgery on day 30. Thirty days of odor deprivation dramatically reduced dopamine and dihydroxyphenylacetic acid levels in functionally-deprived bulbs (ipsilateral to occluded nares) as compared to contralateral controls, while norepinephrine and dihydroxyphenylglycol levels were unchanged. The loss of dopamine was more severe in medial as compared to lateral aspects of experimental bulbs, while the loss of dihydroxyphenylacetic acid was similar on the two sides. To test directly the hypothesis that afferent activity regulates dopamine and dihydroxyphenylacetic acid content, 1 h of high frequency tetanic nerve stimulation was provided to the rostral-medial olfactory nerve layer in deprived olfactory bulbs, and catecholamine levels were assessed from 6 to 192 h later. Partial and temporary recovery of dopamine was observed in medial aspects of the bulb when rats were examined 96 h later, while consistent recovery of dihydroxyphenylacetic acid content was not apparent. These data corroborate evidence that olfactory nerve activity is a potent regulator of bulb dopamine and indicate that continued afferent input is necessary to maintain dopamine levels.     

Lipolytic fermentations of stickwater by Geotrichum candidum and Candida lipolytica

Stickwater, a by-product of the fish meal and oil industry, is an aqueous suspension of fish proteins, lipids, and other materials, and also contains soluble nonprotein nitrogen but not carbohydrate. It is usually partially evaporated by heat to a marketable form called "fish solubles," which is sold with an acid preservative as an animal feed supplement. However, fish solubles are only used to a limited extent in feeds, because the lipids of solubles (averages 11%) are relatively prone to oxidative rancidity development. An investigation was undertaken to digest and/or stabilize lipids in stickwater by lipolytic fermentations and, at the same time, to attempt to increase the protein content as single cell protein. Strains of the yeast Candida lipolytica and the yeast like mold Geotrichum candidum were employed for these investigations. Stickwater fermentations were performed in a laboratory bench top fermentor. Respirometric studies of lipid metabolic activity and microbial observations were periodically performed during these fermentations. Rapid microbial growth and metabolic activity were observed in well aerated cultures. Fermented products were evaluated for chemical composition. Lipid residues were characterized by thin-layer chromatographic procedures. There was evidence of abundant microbial growth, increased lipolytic activity, and decreased lipid content. However, evidence was lacking to show that the protein content of stickwater was actually increased.     

Two new steroidal saponins from Allium sativum and their inhibitory effects on blood coagulability]

Determining the presence of viable myocardium has prognostic and therapeutic implications in the treatment of ischemic heart disease. Dobutamine stress echocardiography (DSE) is one possible technique to help identify both hibernating and stunned but viable myocardium. Low-dose dobutamine infusion has an increased inotropic effect, while higher doses cause both inotropic and chronotropic effects. Thus, at lower doses cardiac augmentation occurs, and at higher doses regions of ischemia may be produced in the presence of significant coronary artery disease. This is manifested echocardiographically as changes in segmental wall motion. In theory, therefore, areas of viable myocardium should show improved wall motion at low doses, and areas of irreversible myocardial damage will remain akinetic. Five studies have investigated DSE for determining viability in the setting of acute myocardial infarction, thus looking for stunned but viable myocardium. DSE was shown to compare favorably with positron emission tomography and was highly sensitive and specific for predicting functional myocardial recovery. Five additional studies examined DSE for determining the presence of hibernating myocardium. The sensitivity and specificity of DSE were found to range from 71 to 92% and from 73 to 93%, respectively. The benefits of DSE include lower cost, convenience to both patient and physician, additional ancillary information, and determination of the possible need for urgent revascularization. Limitations of DSE include occasional technical difficulty in obtaining and interpreting studies and the need for larger volumes of viable myocardium to detect changes predictive of functional recovery. Larger trials are currently underway to confirm DSE as a reliable technique for determining myocardial viability.