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1.
A new oligosaccharide citric acid derivative was isolated by hot aqueous extraction at 85?°C from Vigna angularis seeds, and it was purified using anion exchange chromatography DE-52. The structure was inferred by using UV, 1?D and 2?D NMR spectroscopy and HR-MALDI/MS, and identified as α-D-galactopyranosyl-(1→6)-α-D-galactopyranosyl-(1→6)-α-D-glucopyranosyle-(1→2)-β-D-fructofuranosyle citric acid. The isolated oligosaccharide citric acid derivative revealed promising anti-influenza A virus with 50% inhibition concentration (IC50) of 0.162?nM/mL and 50% cytotoxic dose (CC50) of >2.38?nM/mL.  相似文献   

2.
A determination method has been optimized and validated for the simultaneous analysis of tetracycline (TC), oxytetracycline (OTC), chlortetracycline (CTC) and doxycycline (DC) in honey. Tetracyclines (TCs) were removed from honey samples by chelation with metal ions bound to small Chelating Sepharose Fast Flow columns and eluted with Na2EDTA-Mcllvaine pH 4.0 buffers. Extracts were further cleaned up by Oasis HLB solid-phase extraction (SPE), while other solid-phase extraction cartridges were compared. Chromatographic separation was achieved using a polar end-capped C 18 column with an isocratic mobile phase consisting of oxalic acid, acetonitrile and methanol. LC with ultraviolet absorbance at 355 nm resulted in the quantitation of all four tetracycline residues from honey samples fortified at 15, 50, and 100 ng/g, with liner ranges for tetracyclines of 0.05 to 2 μg/mL. Mean recoveries for tetracyclines were greater than 50% with R.S.D. values less than 10% (n= 18). Detection limits of 5, 5, 10, 10 ng/g for oxytetracycline, tetracycline, chlortetracycline and doxycycline, respectively and quantitation limits of 15 ng/g for all the four tetracyclines were determined. Direct confirmation of the four residues in honey (2-50 ng/g) was realized by liquid chromatography-tandem mass spectrometry (LC/MS/MS). The linear ranges of tetracyclines determined by LC/MS/MS were between 5 to 300 ng/mL, with the linear correlation coefficient r〉 0.995. The limits of detection of 1 to 2 ng/g were obtained for the analysis of the TCs in honey.  相似文献   

3.
Abstract

Two triterpene saponins (IPS-1, IPS-2) for the first time were isolated from the roots of Impatiens parviflora DC. (Balsaminaceae). Their anti-inflammatory activity was evaluated by means of two in vitro models: anti-hyaluronidase and anti-denaturation assays. Both saponins were shown to be potent hyaluronidase inhibitors that affect the enzyme in a dose-dependent manner. The anti-hyaluronidase effect of IPS-2 (IC50?=?286.7?µg/mL) was higher than that of the reference drug: escin (IC50?=?303.93?µg/mL). Both saponins protected bovine serum albumin from heat-induced denaturation in a dose-dependent manner. IPS-1 demonstrated higher anti-denaturation effect (IC50?=?86.7?µg/ml) than IPS-2 (IC50?=?109.76?µg/mL) or the standard drug: acetylsalicylic acid (IC50?=?262.22?µg/mL). In conclusion, potent activity of IPS-1, IPS-2 in both in vitro assays shows that saponins from I. parviflora have anti-inflammatory activity. The obtained results allow to suggest that such compounds may be beneficial in inflammatory conditions, especially associated with excessive degradation of hyaluronic acid.  相似文献   

4.
Abstract

Phytochemical investigation on the biologically active compounds of seaweed Gracilaria salicornia {(C. Agardh) E.Y. Dawson} (family Gracilariaceae) guided to the separation of a previously unreported abeo-labdane class of diterpenoid. The compound was characterized as methyl-16(13→14)-abeo-7-labdene-(12-oxo) carboxylate by extensive spectroscopic experiments, and comparison with the related compounds. The studied compound registered significantly greater activities against pro-inflammatory 5-lipoxygenase (IC50 0.86?mg/mL) than that exhibited by non-steroidal anti-inflammatory agent ibuprofen (IC50 0.92?mg/mL, P?<?0.05). Likewise, this compound exhibited comparable radical quenching (1, 1-diphenyl-2-picryl-hydrazil) activity (IC50 0.66?mg/mL) as standard antioxidant agent α-tocopherol (IC50 0.62?mg/mL).  相似文献   

5.
Natural honey contains an array of glycoproteins, proteoglycans and glycopeptides. Size-exclusion chromatography fractionated Ziziphus honey proteins into five peaks with molecular masses in the range from 10 to >200 kDa. The fractionated proteins exhibited in vitro activities against Giardia lamblia with IC50 values ≤ 25 μg/mL. Results indicated that honey proteins were more active as antiprotozoal agents than metronidazole. This study indicated the potential of honey proteins and peptides as novel antigiardial agents.  相似文献   

6.
Abstract

In Brazilian folk medicine, Protium heptaphyllum is used to treat inflammatory conditions and to hasten wound repair. This paper aims to investigate the chemical composition and the in vitro antibacterial effects of the essential oils (EOs) obtained from P. heptaphyllum leaves and ripe and unripe fruits against a representative panel of oral pathogens. The GC-FID and GC-MS analysis revealed that the major components determined in P. heptaphyllum essential oils were myrcene (59.0%), β-elemene (17.2%), limonene (12.9%), spathulenol (12.6%), α-cubebene (11.6%), germacrene D (10.6%), trans-nerolidol (9.8%), and α-cadinol (8.8%). The essential oils of the ripe and unripe fruits showed the strongest antibacterial activity against the anaerobic bacteria Prevotella nigrescens (MIC?=?50?µg/mL). The leaf essential oil displayed very promising activity against Streptococcus mutans (MIC?=?50?µg/mL) and Streptococcus mitis (MIC?=?62.5?µg/mL). The antibacterial activity of EOs against oral pathogens is also described for the first time.

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7.
Abstract

This study, was to evaluate the acaricidal effect of the essential oil (EO) and fractions (FR) obtained from Laurus nobilis leaves on Rhipicephalus (Boophilus) microplus. Eight fractions were obtained, however FR1: sabinene (37.83%), β-pinene (13.50%), 1,8-cineole (12.66%), α-pinene (12.56%) and FR8: α-terpineol (79.19%) were highlighted as to the larvicidal potential when submitted by Larval Packet Test. The EO was tested by the Adult Immersion Test, at concentrations of 200.00; 100.00 and 50.00?µL/mL caused mortality of engorged females, egg mass reduction and hatching inhibition. Two fractions are shown to be efficient in controlling larvae FR8 (LC50?=?0.13?µL/mL, LC99?=?0.51?µL/mL) and FR1 (LC50?=?0.20?µL/mL, LC99?=?0.56?µL/mL). The fractionation of EO was determinant to elucidate which compounds were responsible for the larvicidal potential. This study opens new perspectives to direct new bioassays with the compounds obtained in the fractionation, since they present high potential on cattle tick larvae.  相似文献   

8.
Abstract

Di-n-butyl- (1) and diethyltin(IV) (2) derivatives of 3-methylphenylethanoic acid were synthesized and characterized by elemental analysis, atomic absorption, IR, 1H and 13C NMR spectroscopy and mass spectrometry. The spectroscopic data and single crystal X-ray diffraction studies for complex 2 have confirmed a bidentate coordination mode of the carboxylate ligand and the presence of hexacoordinated tin atoms in the complexes. The complexes were screened for their in vitro antibacterial activity against selected gram positive and gram negative bacterial strains. The anticancer potential was assessed against prostate cancer cell lines. Both complexes have shown higher activities than the ligand acid. Complex 1 with an IC50 value of 4.97?±?0.27?μg/mL was found to be better anti prostate cancer agent than complex 2 (IC50 = 11.26?±?2.18?μg/mL). Molecular docking study has suggested antibacterial action of the complexes in terms of their ability to develop hydrogen bonding and hydrophobic interactions with vital residues of the target proteins like tyrosyl-tRNA synthase from Staphylococcus aureus (gram-positive bacteria) and undecaprenyl diphosphate synthase from Escherichia coli (gram-negative bacteria).  相似文献   

9.
Abstract

Aloe vera leaf contains some bioactive compounds that have a strong binding affinity toward estrogen receptor as compared to standard drug tamoxifen. In this study, we have found that the IC50 of Aloe vera leaf extract against breast cancer cell line (MCF-7) is 23?µg/mL which is much lower than the IC50 (332?µg/mL) of Aloe vera leaf extract against non-cancerous cell line (NIH-3T3). We have also calculated the total concentration of phenolic acid (385.662?µg/mL), flavonoids (160.402?µg/mL) and alkaloids (276.754?µg/mL) in Aloe vera leaf extract. The free radical scavenging activity of Aloe vera leaf extract is 67% to 89% (at 50 to 300?µg/ml). Our virtual molecular docking study suggests that bioactive compounds like Aloe-emodin (?8.8?Kcal/mol), 7-hydroxy-2,5 dimethylchromone (?7.5?Kcal/mol), Beta-sitosterol (?7.3?Kcal/mol) etc. have a greater binding affinity toward estrogen alpha receptor as compared to standard drug Tamoxifen (?6.4?Kcal/mol).

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10.
In this study, biological properties of the essential oil isolated from seeds of Foeniculum vulgare (F. vulgare) were evaluated. GC-MS analysis revealed Trans-Anethole (80.63%), L-Fenchone (11.57%), Estragole (3.67%) and Limonene (2.68%) were the major compounds of the essential oil. Antibacterial activity of the essential oil against nine Gram-positive and Gram-negative strains was studied using disc diffusion and micro-well dilution assays. Essential oil exhibited the antibacterial activity against three Gram-negative strains of Pseudomonas aeruginosa, Escherichia coli, and Shigella dysenteriae. The preliminary study on toxicity of seed oil was performed using Brine Shrimp lethality test (BSLT). Results indicated the high toxicity effect of essential oil (LC50 = 10 μg/mL). In vitro anticancer activity of seed oil was investigated against human breast cancer (MDA-Mb) and cervical epithelioid carcinoma (Hela) cell lines by MTT assay. Results showed the seed oil behave as a very potent anticancer agent with IC50 of lower than 10 μg/mL in both cases.  相似文献   

11.
A series of novel 8‐OMe ciprofloxacin (8‐OMe CPFX)‐1H‐1,2,3‐triazole‐isatin‐(thio) semicarbazide/oxime hybrids 6a – l with the capacity to form hydrogen bond were designed, synthesized, and evaluated for their in vitro anti‐mycobacterial activities against Mycobacterium tuberculosis (MTB) H37Rv and MDR‐TB as well as cytotoxicity. All the synthesized hybrids (MIC: 0.39–16 μg/mL) exhibited excellent activities against MTB H37Rv and MDR‐TB, and the majority of them were more potent than the parent 8‐OMe CPFX (MIC: 1.56 and 2.0 μg/mL, respectively). In particular, the most active conjugate 6h (MIC: 0.39 and 1.0 μg/mL, respectively) was two to eight times more potent in vitro than the references CPFX (MIC: 3.12 and 4.0 μg/mL, respectively) and 8‐OMe CPFX against the tested strains and was comparable with or 64‐folds more potent than RIF (MIC: 0.39 and 64 μg/mL, respectively) against MTB H37Rv and MDR‐TB, respectively. In addition, all conjugates (CC50: 16–64 μg/mL) showed acceptable cytotoxicity, although most of them were more toxic than the parent (CC50: 64 μg/mL) in VERO cell line.  相似文献   

12.
A new class of propylene‐1H‐1,2,3‐triazole‐4‐methylene‐tethered (thio)semicarbazone‐isatin‐moxifloxacin hybrids 6a – h was designed, synthesized, and screened for their in vitro anti‐mycobacterial activities against Mycobacterium tuberculosis (MTB) H37Rv and MDR‐TB as well as cytotoxicity in VERO cell line. All the synthesized hybrids (MIC: 0.05–2.0 μg/mL) exhibited excellent activities against M. tuberculosis H37Rv and MDR‐TB; in particular, conjugate 6c (MIC: 0.05 and 0.12 μg/mL) was no inferior to the three references MXFX (MIC: 0.10 and 0.12 μg/mL), RIF (MIC: 0.39 and 32 μg/mL), and INH (MIC: 0.05 and >128 μg/mL) against the tested two strains. All hybrids (CC50: 2–8 μg/mL) were much more cytotoxic than the parent MXFX (CC50: 128 μg/mL) should be further optimized.  相似文献   

13.
A new set of ciprofloxacin (CPFX)‐isatin‐1H‐1,2,3‐triazole hybrids 6a – l with greater lipophilicity compared with the parent CPFX was designed, synthesized, and assessed for their in vitro anti‐mycobacterial activity against Mycobacterium tuberculosis (MTB) H37Rv as well as cytotoxicity in VERO cell line. The preliminary results showed that all hybrids (MIC: 0.39–50 μg/mL) exhibited promising activities against MTB H37Rv, and six of them (MIC: 0.39–1.56 μg/mL) were more active than the parent CPFX (MIC: 3.12 μg/mL). In particular, the most active conjugate 6h (MIC: 0.39 μg/mL) was comparable with RIF (MIC: 0.39 μg/mL), and eight times more potent than CPFX. All conjugates (CC50: 4–64 μg/mL) were more toxic than the parent (CC50: 128 μg/mL) in VERO cell lines, and the most active hybrids, which also displayed the highest cytotoxicity, should be further optimized.  相似文献   

14.
The fumigant toxicity of Xylopia parviflora (A. Rich.) Benth (Annonaceae) root bark's essential oil (EO) against cowpea seed bruchid, Callosobruchus maculatus, was investigated in the laboratory. Dose had significant (P < 0.0001) effect on mortality at 6 hours after treatment (HAT) at a concentration of 6.25 μL/mL air which exerted 81.70% mortality, while there was no mortality in all other lower doses. At 12 HAT, 75.05% and 90.00% mortality were observed at doses of 3.15 and 6.25 μL/mL air, respectively. It was significantly (P < 0.05) higher than the mortality (50.58%) observed when 0.78 μL/mL air was applied. The lethal time for 50% of assayed adults (LT50) obtained when the bruchid was exposed to X. parviflora EO at a dose of 6.25 μL/mL air (2.71 h) was significantly lower than LT50 obtained at exposure of bruchid to other lower doses of 0.78–3.15 μL/mL air.  相似文献   

15.
In the quest for bioactive natural products of fungal origin, Aspergillus flavus was isolated from rhizosphere of Mentha piperita using Potato Dextrose Agar (PDA) and Czapec Yeast Broth (CYB) nutrient media for metabolites production. In total, three different metabolites were purified using HPLC/LCMS and the structures were established using 500 Varian NMR experiments. Further the isolated metabolites in different concentrations (10, 100, 1000 μg/mL) were tested for herbicidal activity using Completely Randomized design (CRD) against the seeds of Silybum marianum and Avena fatua which are major threats to wheat crop in Pakistan. Among the isolated metabolites, one compound was found active against the test weed species whose activity is reported in the present work. The chemical name of the compound is 2-(1, 4-dihydroxybutan-2-yl)-1, 3-dihydroxy-6, 8-dimethoxyanthracene-9, 10(4aH, 9aH)-dione with mass of 388. Results showed that all seeds germinated in control treatment; however, with the metabolite treated, the growth was retarded to different levels in all parts of the weeds. At a dose of 1000 μg/mL of the pure compound, 100% seeds of S. marianum and 60% seeds of A. fatua were inhibited. Interestingly, the pure compound exhibited less inhibition of 10% towards the seeds of common wheat (Triticum aestivum).  相似文献   

16.
Abstract

A fishing platform was developed using immobilized capillary enzyme reactors in combination with liquid chromatography-mass spectrometry (LC-MS) to fish acetylcholinesterase inhibitor (AChEI) from Mahonia bealei (Fort.) Carr. (M. bealei) extract. Four potential AChEIs (columbamine, jatrorrhizine, berberine, and palmatine) were successfully screened out and identified. Their AChE inhibitory activities were further verified by an in vitro assay with IC50 values of 0.93?±?0.12?μg/mL (columbamine), 3.50?±?0.15?μg/mL (jatrorrhizine), 2.51?±?0.12?μg/mL (berberine), and 1.52?±?0.13?μg/mL (palmatine). A synergy study of these AChEIs was subsequently investigated. In comparison with the IC50 value of M. bealei extract (IC50=0.83?±?0.21?μg/mL), it can be stated that M. bealei extract is much more active than any single AChEI. Thereafter, the determination of these four alkaloids were investigated and AChE inhibitory effect were compared in terms of the extract and corresponding contents of these four alkaloids. The inhibitory effects of extract at each concentration were stronger than four alkaloids mixture. The results demonstrated that not the four AChEI mixture cause the synergistic effect but rather than the concentrations or ratios of these AChEIs play a vital role in their synergy study.  相似文献   

17.
Abstract

Four xanthones (1?4) and a known compound, mansonone D (5), were isolated from the lignicolous freshwater fungus BCC 28210 (family, Chaetosphaeriaceae). The structures of these compounds were elucidated by extensive spectroscopic analysis. Among the isolated metabolites, compound 2 and the known mansonone D (5) displayed antimalarial activity against Plasmodium falciparum K1 with IC50 values of 7.75 and 0.55?μg/mL, respectively. Compound 4 displayed antibacterial activity against Bacillus cereus with an MIC value of 6.25?μg/mL.  相似文献   

18.
Isatin and coumarin derivatives with potential anti‐tubercular activity, while (thio)semicarbazide/oxime and 1H‐1,2,3‐triazole moieties exhibited favorable properties such as hydrogen bonding and/or metal chelation capability, so integration of the four pharmacophores into one molecule may provide more effective anti‐tubercular candidates. Based on the consideration earlier, 12 isatin‐(thio)semicarbazide/oxime‐1H‐1,2,3‐triazole‐coumarin hybrids 8a–l were designed, synthesized, and evaluated for their in vitro anti‐mycobacterial activities against M. tuberculosis (MTB) H37Rv and MDR‐TB. The results showed that all the hybrids (MIC: 50–>200 μg/mL) exhibited weak to moderate inhibitory activity against MTB H37Rv and MDR‐TB, which were far less potent than the references isoniazid (MIC: 0.05 μg/mL) and rifampicin (MIC: 0.39 μg/mL) against MTB H37Rv. The most active hybrid 8h (MIC: 50 μg/mL) was comparable with rifampicin (MIC: 32 μg/mL) and more active than isoniazid (MIC: >128 μg/mL) against MDR‐TB, could be act as a lead for further optimization. Moreover, the enriched structure–activity relationship paved the way to the further rational development of this kind of hybrids.  相似文献   

19.
In continuing our efforts to find new effective antimicrobial agents for overcoming the problem of microbial resistance, a new series of functionalized 5-hetarylthiazoles have been designed and synthesized starting from readily accessible 1-(2-allylamino-4-methylthiazol-5-yl)ethanone (3). The structures of newly synthesized compounds were confirmed by elemental analyses, spectral data, and chemical transformations. The synthesized compounds were evaluated in vitro for their antimicrobial activity against some human pathogenic bacterial and fungal strains. The compounds 7, 18, and 24 exhibited higher antibacterial activity with minimum inhibitory concentration (MIC) values ranging from (0.03–0.06?µg/mL) than ampicillin (MIC, 0.12?µg/mL) against Streptococcus pneumoniae. Whereas compounds 4, 22, and 24 revealed higher antifungal potency than amphotericin B against Aspergillus fumigatus. The structure and antimicrobial activity relationship was also discussed.  相似文献   

20.
Abstract

A new rotenoid named 12-O-methylrotenolol along with five known rotenoid and isoflavone metabolites were isolated from the seeds of Dalbergia lanceolaria subsp. paniculata, collected from Egypt. The structures of these compounds were identified by physical and spectroscopic data measurements ([α]D, UV, 1D- and 2D-NMR and MS). The methanol extract of the seeds exhibited strong antioxidant activity with IC50 value 0.7?µg/µl against DPPH radical, in respect to quercetin as antioxidant reference (IC50 1.5?μM), while the tested compounds from this extract showed weak activities with IC50 values ranged from 19.6 to 33.0?µM.  相似文献   

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