Steroidal glycosides from Ornithogalum thyrsoides bulbs and their cytotoxicity toward HL-60 human promyelocytic leukemia cells and SBC-3 human small-cell lung cancer cells.

Ornithogalum thyrsoides Jacq belongs to the Asparagaceae family and is cultivated for ornamental purposes. The authors have previously reported several cholestane- and spirostan-type steroidal glycosides from O. thyrsoides. Conventional TLC analysis of the methanolic bulb extract of O. thyrsoides suggested the presence of unprecedented compounds; therefore, a detailed phytochemical investigation of the extract was performed and 35 steroidal glycosides (1-35), including 21 previously undescribed ones (1-21) were collected. The structures of 1-21 were determined mainly by analyses of their 1H and 13C NMR spectra with the aid of two-dimensional NMR spectroscopy. The isolated compounds were classified into three distinct groups: furostan-type (1, 2, 8-12, and 22), spirostan-type (3-7 and 23-26), and cholestane-type (13-21 and 27-35). Although the C/D-ring junction of the steroidal skeleton is typically trans-oriented, except for some cardiotonic and pregnane-type steroidal derivatives, 7 possess a cis C/D-ring junction. This is the first reported instance of such a configuration in spirostan-type steroidal derivatives, marking it as a finding of significant interest. Compounds 1-35 were evaluated for cytotoxicity against HL-60 human promyelocytic leukemia cells and SBC-3 human small-cell lung cancer cells. Compounds 3-6, 9, 17-21, 23-25, and 30-35 demonstrated cytotoxicity in a dose-dependent manner with IC50 values ranging from 0.000086 to 18 µM and from 0.00014 to 37 µM toward HL-60 and SBC-3 cells, respectively. Compound 19, which is obtained in a good yield and shows relatively potent cytotoxicity among the undescribed compounds, induces apoptosis in HL-60 cells, accompanied by arresting the cell cycle of HL-60 cells at the G2/M phase. In contrast, 19 causes oxidative stress-associated necrosis in SBC-3 cells. The cytotoxic mechanism of 19 is different between HL-60 and SBC-3 cells.

Systematic analysis of the codon usage patterns of African swine fever virus genome coding sequences reveals its host adaptation phenotype.

African swine fever (ASF) is a severe haemorrhagic disease caused by the African swine fever virus (ASFV), transmitted by ticks, resulting in high mortality among domestic pigs and wild boars. The global spread of ASFV poses significant economic threats to the swine industry. This study employs diverse analytical methods to explore ASFV's evolution and host adaptation, focusing on codon usage patterns and associated factors. Utilizing phylogenetic analysis methods including neighbour-joining and maximum-likelihood, 64 ASFV strains were categorized into four clades. Codon usage bias (CUB) is modest in ASFV coding sequences. This research identifies multiple factors - such as nucleotide composition, mutational pressures, natural selection and geographical diversity - contributing to the formation of CUB in ASFV. Analysis of relative synonymous codon usage reveals CUB variations within clades and among ASFVs and their hosts. Both Codon Adaptation Index and Similarity Index analyses confirm that ASFV strains are highly adapted to soft ticks (Ornithodoros moubata) but less so to domestic pigs, which could be a result of the long-term co-evolution of ASFV with ticks. This study sheds light on the factors influencing ASFV's codon usage and fitness dynamics, enriching our understanding of its evolution, adaptation and host interactions.

Phytochemical fingerprint and biological activity of raw and heat-treated Ornithogalum umbellatum.

The plants that we use as food in our daily diet and as risk preventers against many diseases have many biological and pharmacological activities. The heat treatments applied during the cooking of the plants cause changes in the phytochemical content and bioactivity. In this study, the phytochemical fingerprint and biological activities of raw and heat-treated extracts of Ornithogalum umbellatum L., which is widely consumed in the Black Sea region, were investigated. The bulb and leaf parts of the plant consumed as food were dried in an oven at 35 °C and then ground into powder. For heat treatment, the plant was boiled at 100 °C for 20 min. Differences in phytochemical contents of raw and heat-treated extracts were determined by ICP-MS, LC-MS/MS, and FTIR analysis. Biological activity was investigated with antiradical, antimicrobial, antimutagenic and antiproliferative activity tests. In this way, the effect of heat treatment on both the phytochemical content and biological activity of the O. umbellatum extract was determined. Gallic acid, procateuic acid and caffeic acid were found as the main compounds in the O. umbellatum extract, while the presence of procateuic aldehyde, vanillin and kaempferol in minor proportions was determined. There was a significant decrease in phenolic compound levels after heat treatment and gallic acid content decreased by 92.6%, procateuic acid content by 90% and caffeic acid content by 84.8%. Significant differences were detected in macro and micro element levels after heat treatment in ICP-MS results. While Cd, Ba and Zn levels of the raw extract increased; Na, Mg, K, Fe, U, Co levels decreased significantly. In FTIR spectrum, shifts and disappearances were observed in some of the vibrations and the emergence of new vibrations was also determined after heat treatment. Raw extract exhibited strong scavenging activity against H2O2 and DPPH and had a broad spectrum antimicrobial property. As a result of heat application, regressions were detected in antiradicalic, antibacterial and antifungal activities. Antimutagenic and antiproliferative activities were determined by the Allium test and a significant decrease in both activities and loss of activity against some chromosomal abnormalities were determined after heat treatment. While the antiproliferative activity of the raw extract was 20%, the activity of the heat-treated extract decreased to 7.6%. The raw extract showed the strongest antimutagenic effect with 69.8% against the unequal distribution of chromatin. Similarly, the antimutagenic activity of the extract, which reduced the bridges by 56.1%, decreased to 0.74% after heat treatment and almost lost its antimutagenic activity. The biological activities of raw O. umbellatum are closely related to the major compounds it contains, and the decrease in the levels of these compounds with the effect of heat was reflected in the activity. Studies investigating the phytochemical contents of plants are very important and the studies investigating biological activities related to phytochemical content are more remarkable. In this study, the phytochemical fingerprint of O. umbellatum was determined, its biological activities were related to the compounds it contained, and the biological activity was found to be heat sensitive.

Optimum Reaction Conditions for the Synthesis of Selenized Ornithogalum caudatum Ait. (Liliaceae) Polysaccharides and Measurement of Their Antioxidant Activity In Vivo.

This study determined the optimum reaction conditions for synthesizing selenium-containing polysaccharides. Polysaccharide IIA (with the highest yield) from Ornithogalum caudatum Ait. (Liliaceae) (OCAPIIA) was extracted and purified. Then, three parameters were selected to optimize the synthesis of selenized OCAPIIA (Se-OCAPIIA) using the Box-Behnken design (BBD) and response surface methodology (RSM). The morphology of Se-OCAPIIA was analyzed by scanning electron microscopy (SEM). The characteristic peaks and the monosaccharide composition of Se-OCAPIIA were evaluated by Fourier-transform infrared spectroscopy and gas chromatography. A D-galactose-induced aging mouse model was established, and the in vivo antioxidant activity of Se-OCAPIIA was measured. The optimal conditions for the synthesis of Se-OCAPIIA were as follows: reaction temperature, 72.38 °C; Na2SeO3 to OCAPIIA mass ratio, 0.93 g/g; and reaction time, 8.05 h. The selenium content of Se-OCAPIIA obtained using the optimized process was 3.131 ± 0.090 mg/g, close to the maximum predicted value (3.152 mg/g). Se-OCAPIIA contained D-mannose, D-glucose, and D-galactose at a molar ratio of 1.00:0.34:0.88. SEM showed that Se-OCAPIIA was spherical and flocculated. Compared with OCAPIIA, Se-OCAPIIA exhibited two characteristic peaks at 833 and 610 cm-1 in the infrared spectrum. Se-OCAPIIA increased catalase, glutathione peroxidase, and superoxide dismutase activities and decreased MDA concentrations in the mouse liver. Moreover, Se-OCAPIIA treatment improved liver morphology, decreased the levels of IL-1ß and IL-6, and increased IL-10 concentration. In conclusion, the synthesis of Se-OCAPIIA is effective, simple, and feasible. Se-OCAPIIA demonstrated high antioxidant activity in vivo and is a promising antioxidant and therapeutic agent.

Correlations between rheological and mechanical properties of fructo-polysaccharides extracted from Ornithogalum billardieri as biobased adhesive for biomedical applications.

Polysaccharides are extracted from Ornithogalum by maceration using different ultrasound (US) treatment times (0%US, 50%US, 100%US), and under optimized extraction conditions (OP%US). The total carbohydrates content (TCC) and proteins content of the extracts were determined. Data show that the extraction parameters significantly influence the extracts composition. Rheological measurements allowed determining the liquid, intermediate and gel states of the extract's solutions. The adhesion strength of the solutions was evaluated on paper and polylactide (PLA) substrates to evaluate their potential as environmentally friendly adhesive. OP%US presents the highest adhesion strength (1418.3 kPa) on paper, and is further tested on pork skin substrates. The adhesion strength is higher on skin/paper (870 kPa) than on skin/skin (411 kPa) substrate due to the capillary force of paper which allows penetration of adhesive into the micropores of paper. The correlation between rheological properties and adhesion strength indicates that the adhesion strength strongly depends on the state of adhesives and the substrate type. SEM analyses show that higher adhesion strength (intermediate and gel states) involves both cohesive and adhesive failure, whereas only adhesive failure is observed in liquid state on PLA substrates. Therefore, these polysaccharides extracts could be very promising as tissue adhesive in medical applications.

Characterization of the Phenolic Profile and Antioxidant Activity of Cathissa reverchonii (Lange) Speta.

Cathissa reverchonii (formerly Ornithogalum reverchonii) is a threatened species, constituting an endemism present in the south of Spain and northern Morocco. In Spain, it is only found in two disjoint populations in the region of Andalusia. The determination of its chemical composition and the influence that environmental factors have on it can contribute significantly to the development of appropriate protection and conservation plans. However, there are no previous reports about this species to date. Consequently, this research aimed to study the phenolic composition and antioxidant activity of C. reverchonii and to assess the influence of environmental factors on the phenolic profile and bioactivity. The vegetal material was collected in seven places inhabited by the two separate populations in Spain. The phenolic composition of methanolic extracts of the species was determined by HPLC-ESI-Q-TOF-MS, and the antioxidant activity was assessed by DPPH and ABTS assays. Fifteen compounds were characterized in the extracts of the aerial parts of C. reverchonii, revealing differences in the phytochemical profile between both populations analyzed, mainly in the saponin fraction. The main phenolics were flavone di-C-glucoside (lucenin-2), followed by a quercetin-di-C-glucoside. The composition of the extracts of C. reverchonii and their radical scavenging power were compared with those of other species of the genus Ornithogalum L., revealing significant differences between the latter and the genus Cathissa.

In vitro Cytotoxic Screening of Different Parts from Ornithogalum bungei on Selected Cancer Cells.

BACKGROUND: Natural products comprise a large section of pharmaceutical agents in the field of cancer therapy. In the present study, the organic extracts and fractions of various parts of Ornithogalum bungei were investigated for in vitro cytotoxic properties on three human cancer cell lines, hepatocellular carcinoma (HepG2), prostate cancer (PC3), and leukemia (K562) cells. METHODS: The present experimental study was conducted at Tehran University of Medical Sciences (Tehran, Iran) during 2017-2019. Separately extracted plant materials, including bulbs, stems, and flowers of O. bungei were assessed by the tetrazolium dye-based colorimetric assay (MTT). The selected extracts were submitted to fractionation using vacuum liquid chromatography and after MTT assay, the half maximal inhibitory concentration (IC50 (value for each fraction was determined. The data were analyzed using One-way ANOVA followed by Tukey's post hoc test. P<0.05 was considered statistically significant. RESULTS: The cytotoxicity of the bulb's methanol extract and the dichloromethane extract of aerial parts increased in a concentration-dependent manner. Additionally, cell viability decreased in a dose-dependent manner. In the HepG2 cell line, the best IC50 values of fractions from DCM extracts of aerial parts were determined to be 19.8±10.2 µg/mL after 24 hours of exposure and 19.39±6.4 µg/mL following 48 hours of exposure. In the PC3 cell line, after 48 hours of exposure, the IC50 values of fractions were unaccountable, while the percentage of inhibition for A6 to A11 in 24 hours of exposure was more than 40 µg/mL. CONCLUSION: O. bungei growing in Iran showed significant potentials as a cytotoxic agent with selective effects on different cancer cell lines.

Selective obstruction of the mTORC2 complex by a naturally occurring cholestane saponin (OSW-1) for inhibiting prostate cancer cell growth.

Ornithogalum caudatum Ait (OCA) is a natural product used in Chinese traditional medicine. The cholestane saponin OSW-1 is isolated from plant OCA and has recently been shown to have potent cytotoxic effects against different types of cancers. The therapeutic efficacy of OSW-1 on prostate cancer and its underlying mechanism are yet to be established. OSW-1 inhibited the growth of prostate cancer cells by interrupting the interaction between mTOR and Rictor/mTORC2. This mechanism showed a better therapeutic outcome than that of the conventional inhibition of mTOR and provided a basis for as sisting modern prostate cancer treatment strategies.

Glycodiversifying Testosterone with a Promiscuous Glycosyltransferase OsSGT2 from Ornithogalum saundersiae.

The diversity expansion of testosterone17-O-ß-glycosides (TGs) will increase the probability of screening more active molecules from their acetylated derivatives with anticancer activities. Glycosyltransferases (GTs) responsible for the increased diversity of TGs, however, were seldom documented. Herein, a glycosyltransferase OsSGT2 with testosterone glycodiversification capacity was identified from Ornithogalum saundersiae through transcriptome-wide mining. Specifically, OsSGT2 was demonstrated to be reactive with testosterone and eight donors. OsSGT2 displayed both sugar-aglycon and sugar-sugar GT activities. OsSGT2-catalyzed testosterone glycodiversification could be achieved, generating testosterone monoglycosides and disglycosides with varied percentage conversions. Among the eight donors, the conversion of UDP-Glc was the highest, approaching 90%, while the percentage conversions of UDP-GlcNAc, UDP-Gal, helicin, and UDP-Rha were less than 10%. Protein engineering toward F395 was thus performed to improve the conversion of UDP-GlcNAc. Eight variants displayed increased conversions and the mutant F395C got the highest conversion of 72.11 ± 7.82%, eight times more than that of the wild-type. This study provides a promising alternative for diversity expansion of TGs, also significant insights into the molecular basis for the conversion improvement of sugar donors.

Complete genome sequence of ornithogalum virus 3.

Ornithogalum thyrsoides, a widely cultivated bulbous ornamental plant endemic to South Africa, has significant commercial value as a pot plant and for the production of cut flowers. However, infection by viruses threatens the success of commercial cultivation, as symptoms negatively affect the appearance of the plant and flowers. To date, four Ornithogalum-infecting viruses have been reported. Complete genome sequence data are available for three of these viruses, but the genome of the potyvirus ornithogalum virus 3 (OV3) has not been fully sequenced. In this study, the complete sequence of OV3 was determined by high-throughput sequencing (HTS) and validated by Sanger sequencing. Based on recognition of protease cleavage patterns and multiple sequence alignments with closely related viruses, the polyprotein of OV3 was predicted to be proteolytically cleaved to produce 10 mature peptides containing domains conserved in members of the genus Potyvirus. Phylogenetic analysis and species demarcation criteria confirm the previous classification of OV3 as a member of a separate species in this genus. This is the first report of a complete genome sequence of OV3.

Optimization of polysaccharides extraction from a wild species of Ornithogalum combining ultrasound and maceration and their anti-oxidant properties.

Polysaccharides were extracted from a wild species of Ornithogalum by using three methods: maceration, ultrasound-assisted extraction, and combination of maceration and ultrasound. Extraction conditions were optimized by using response surface method (RSM) with a central composite design (CCD). The optimal extraction yield was 81.7%, 82.5% and 85.7%, and the optimal polysaccharides yield was 74.7%, 75.7%, and 82.8% under the optimum conditions of maceration, ultrasound-assisted extraction and combined extraction, respectively. These results indicate that the combination method significantly improves the extraction and polysaccharides yields compared to traditional extraction methods. The combination method also allows reducing the time of ultrasound treatment and thus its adverse effects on polysaccharides. In addition, these results well corroborate with the theoretically predicted values. The NMR (1H,13C, HSQC, HMBC, and COSY) analysis shows that the extract is composed of fructo-polysaccharides with a backbone of (2 â†’ 6)-linked ß-d-fructofuranosyl (Fruf) and (2 â†’ 1)-linked ß-d-Fruf branched chains, and terminated with glucose and fructose residues. The antioxidant activities of the extract were evaluated from ABTS radical scavenging activity, total antioxidant capacity, metal-chelating power and ß-carotene bleaching test. Data show that the extract presents outstanding antioxidant activities.

OSW-1 inhibits tumor growth and metastasis by NFATc2 on triple-negative breast cancer.

OSW-1 is a natural compound extracted from the bulbs of Ornithogalum saundersiae in 1992. It has been shown strong antitumor activities in various cancer cells. However, the effects of OSW-1 on tumor growth and metastasis in breast cancer are still poorly understood. In our research, we showed that OSW-1 had a strong anticancer effect on breast cancer cells, but lower toxicity to normal cells. Accordingly, it also revealed significant inhibition of tumor growth by OSW-1 in xenograft model. In addition, we performed Annexin V/PI-labeled flow cytometric assay and TUNEL assay and showed that OSW-1 inhibited tumor growth by inducing apoptosis. Furthermore, we carried out transwell assays and found that OSW-1 significantly repressed the migratory and invasive capabilities of triple-negative breast cancer (TNBC) cells via mediating epithelial-mesenchymal transition. Besides, OSW-1 also could inhibit metastasis in an orthotopic model and resulted in a longer survival compared with control group. Finally, we performed RNA-sequencing and cellular functions to investigate the molecular mechanism of how OSW-1 inhibits TNBC, and identified NFATc2 may as a pivotal factor for OSW-1-mediated effects on cell death, tumor growth, invasion, and migration.

OcUGT1-Catalyzing Glycodiversification of Steroids through Glucosylation and Transglucosylation Actions.

Steroidal glycosides are important sources of innovative drugs. The increased diversification of steroidal glycosides will expand the probability of discovering active molecules. It is an efficient approach to diversify steroidal glycosides by using steroidal glycosyltransferases. OcUGT1, a uridine diphosphate-d-glucose (UDP-Glc)-dependent glycosyltransferase from Ornithogalum caudatum, is a multifunctional enzyme, and its glycodiversification potential towards steroids has never been fully explored. Herein, the glycodiversification capability of OcUGT1 towards 25 steroids through glucosylation and transglucosylation reactions were explored. Firstly, each of 25 compounds was glucosylated with UDP-Glc. Under the action of OcUGT1, five steroids (testosterone, deoxycorticosterone, hydrocortisone, estradiol, and 4-androstenediol) were glucosylated to form corresponding mono-glucosides and biosides. Next, OcUGT1-mediated transglucosylation activity of these compounds with another sugar donor ortho-nitrophenyl-ß-d-glucopyranoside (oNPGlc) was investigated. Results revealed that the same five steroids could be glucosylated to generate mono-glucosides and biosides by OcUGT1 through transglucosylation reactions. These data indicated that OcUGT1-assisted glycodiversification of steroids could be achieved through glucosylation and transglucosylation reactions. These results provide a way to diversify steroidal glycosides, which lays the foundation for the increase of the probability of obtaining active lead compounds.

Seven new 1-oxygenated cholestane glycosides from Ornithogalum saundersiae.

As the continuous scientific research, seven new 1-oxygenated cholestane glycosides named osaundersiosides 1 A - 1 G were isolated from an EtOH extract of the bulbs of Ornithogalum saundersiae. Their structures were deduced by means of spectroscopic data, chemical evidence and the results of hydrolytic cleavage. The cytotoxicity and anti-inflammatory effects of osaundersiosides 1 A - 1 G were evaluated, but none of them displayed significant activities. [Formula: see text].

Complete genome sequence of a novel polerovirus in Ornithogalum thyrsoides from South Africa.

Ornithogalum thyrsoides, commonly known as chincherinchee, is an indigenous ornamental plant widely cultivated in South Africa. It is commercially valued as a flowering pot plant and for the production of cut flowers. Virus infections resulting in the development of severe necrotic mosaic symptoms threaten the success of commercial cultivation. The virome of an O. thyrsoides plant displaying necrotic mosaic symptoms was determined using high-throughput sequencing (HTS). In this plant, ornithogalum mosaic virus and ornithogalum virus 3 were identified, as well as a previously unknown virus. The full genome sequence of this virus was confirmed by Sanger sequencing using overlapping amplicons combined with rapid amplification of cDNA ends (RACE). Based on genome organisation and phylogenetic analysis, this novel virus can be classified as a polerovirus.

Structural Elucidation of Three Novel Kaempferol O-tri-Glycosides that Are Involved in the Defense Response of Hybrid Ornithogalum to Pectobacterium carotovorum.

Ornithogalum is an ornamental flowering species that grows from a bulb and is highly susceptible to soft-rot disease caused by Pectobacterium carotovorum (Pc). Interspecific hybridization between O. thyrsoides and O. dubium yielded hybrids with enhanced resistance to that pathogen. The hybrids displayed distinct phenolic-compound profiles with several peaks that were specifically heightened following Pc infection. Three of these compounds were isolated and identified as novel kaempferol O-tri-glycosides. The structures of these compounds were elucidated using reversed phase high-performance liquid chromatography (RP-LC), RP-LC coupled to high-resolution mass spectrometry (RP-LC-MS), and nuclear magnetic resonance (NMR) (1D 1H and 13C, DEPT, HMQC, HMBC, COSY, and NOE), in order to achieve pure and defined compounds data. The new compounds were finally identified as kaempferol 3-O-[4-O-α-l-(3-O-acetic)-rhamnopyranosyl-6-O-ß-d-xylopyranosyl]-ß-d-glucopyranoside, kaempferol 3-O-[4-O-α-l-(2-O-acetic)-rhamnopyranosyl-6-O-ß-d-xylopyranosyl]-ß-d-glucopyranoside and kaempferol 3-O-[4-O-α-l-(2,3-O-diacetic)-rhamnopyranosyl-6-O-ß-d-xylopyranosyl]-ß-d-glucopyranoside.

Spotting plants' microfilament morphologies and nanostructures.

The tracheary system of plant leaves is composed of a cellulose skeleton with diverse hierarchical structures. It is built of polygonally bent helical microfilaments of cellulose-based nanostructures coated by different layers, which provide them high compression resistance, elasticity, and roughness. Their function includes the transport of water and nutrients from the roots to the leaves. Unveiling details about local interactions of tracheary elements with surrounding material, which varies between plants due to adaptation to different environments, is crucial for understanding ascending fluid transport and for tracheary mechanical strength relevant to potential applications. Here we show that plant tracheary microfilaments, collected from Agapanthus africanus and Ornithogalum thyrsoides leaves, have different surface morphologies, revealed by nematic liquid crystal droplets. This results in diverse interactions among microfilaments and with the environment; the differences translate to diverse mechanical properties of entangled microfilaments and their potential applications. The presented study also introduces routes for accurate characterization of plants' microfilaments.

Characterization of two flavonol synthases with iron-independent flavanone 3-hydroxylase activity from Ornithogalum caudatum Jacq.

BACKGROUND: Flavonol synthase (FLS) is the key enzyme responsible for the biosynthesis of flavonols, the most abundant flavonoids, which have diverse pharmaceutical effects. Flavonol synthase has been previously found in other species, but not yet in Ornithogalum caudatum. RESULTS: The transcriptome-wide mining and functional characterisation of a flavonol synthase gene family from O. caudatum were reported. Specifically, a small FLS gene family harbouring two members, OcFLS1 and OcFLS2, was isolated from O. caudatum based on transcriptome-wide mining. Phylogenetic analysis suggested that the two proteins showed the closest relationship with FLS proteins. In vitro enzymatic assays indicated OcFLS1 and OcFLS2 were flavonol synthases, catalysing the conversion of dihydroflavonols to flavonols in an iron-dependent fashion. In addition, the two proteins were found to display flavanone 3ß-hydroxylase (F3H) activity, hydroxylating flavanones to form dihydroflavonols. Unlike single F3H enzymes, the F3H activity of OcFLS1 and OcFLS2 did not absolutely require iron. However, the presence of sufficient Fe2+ was demonstrated to be conducive to successive catalysis of flavanones to flavonols. The qRT-PCR analysis demonstrated that both genes were expressed in the leaves, bulbs, and flowers, with particularly high expression in the leaves. Moreover, their expression was regulated by developmental and environmental conditions. CONCLUSIONS: OcFLS1 and OcFLS2 from O. caudatum were demonstrated to be flavonol synthases with iron-independent flavanone 3-hydroxylase activity.

Steroidal glycosides from Ornithogalum dubium Houtt.

The phytochemical study of Ornithogalum dubium Houtt. (Asparagaceae) led to the isolation of five undescribed steroidal glycosides together with two known ones. Their structures were established by using NMR analysis and mass spectrometry as (25R)-3ß-hydroxyspirost-5-en-1ß-yl O-α-L-arabinopyranosyl-(1 → 2)-α-L-rhamnopyranoside, (25S)-3ß-hydroxyspirost-5-en-1ß-yl O-ß-D-glucopyranosyl-(1 → 6)-ß-D-glucopyranoside, (22S)-16ß-[(α-L-rhamnopyranosyl)oxy]-22-hydroxycholest-5-en-3ß-yl O-ß-D-glucopyranosyl-(1 → 4)-ß-D-glucopyranoside, (22S,23S)-1ß,3ß,11α,16ß,23-pentahydroxy-5α-cholest-24-en-22ß-yl ß-D-glucopyranoside, (22S,23S)-3ß-[(ß-D-glucopyranosyl)oxy]-22,23-dihydroxy-5α-cholest-24-en-16ß-yl O-α-L-rhamnopyranosyl)-(1 → 4)-ß-D-glucopyranoside. Their cytotoxic activities against two human cells, a lung carcinoma A-549 and a promyelocytic leukemia HL-60 cell lines, were evaluated by using the XTT method. The results showed no significant cytotoxicity on the tested cells. The influence of the potentiation of cisplatin cytotoxicity in A-549 cells was also investigated and a slight effect was observed only for the (25R) spirostane-type derivative.

Cholestane glycosides from Ornithogalum saundersiae bulbs and the induction of apoptosis in HL-60 cells by OSW-1 through a mitochondrial-independent signaling pathway.

A search for cytotoxic cholestane glycosides from Ornithogalum saundersiae bulbs resulted in the isolation of three new OSW-1 analogues (1-3), a new cholestane bisdesmoside (4), a 5ß-cholestane diglycoside (5), and four new 24(23 → 22)-abeo-cholestane glycosides (6-9), together with 11 known cholestane glycosides (10-20), including OSW-1 (11). The structures of 1-9 were determined based on conventional spectroscopic analysis and chemical evidence. As expected, based on previous data, 1-3 exhibited potent cytotoxic activity against HL-60 human promyelocytic leukemia cells and A549 human lung adenocarcinoma cells. Furthermore, the ability of OSW-1 to induce apoptosis in HL-60 cells was examined. Aggregation of nuclear chromatin, accumulation of the sub-G1 cells, DNA fragmentation, and caspase-3 activation were assessed in HL-60 cells treated with OSW-1, providing evidence for OSW-1-induced apoptosis in HL-60 cells. No mitochondrial membrane potential or release of cytochrome c into the cytoplasm were observed in the OSW-1-treated apoptotic HL-60 cells, indicating that a mitochondria-independent signaling pathway is involved in apoptotic cell death.