Antibacterial, antifungal and cytotoxic activities of two flavonoids from Retama raetam flowers

We have investigated the antibacterial, antifungal and cytotoxic activities of two flavonoids isolated from Retama raetam flowers using the disc diffusion and micro-dilution broth methods. The cytotoxic activity was tested against Hep-2 cells using the MTT assay. The compounds licoflavone C (1) and derrone (2) were active against Pseudomonas aeruginosa and Escherichia coli (7.81-15.62 μg/mL) and showed important antifungal activity. Strong antifungal activity against Candida species (7.81 μg/mL) was for example found with compound 2. The tested compounds also showed strong cytotoxicity against Hep-2 cells. These two compounds may be interesting antimicrobial agents to be used against infectious diseases caused by many pathogens.     

Two Ecdysteroids Isolated from Micropropagated Lychnis flos-cuculi and the Biological Activity of Plant Material

Genetically uniform plant material, derived from Lychnis flos-cuculi propagated in vitro, was used for the isolation of 20-hydroxyecdysone and polypodine B and subjected to an evaluation of the antifungal and antiamoebic activity. The activity of 80% aqueous methanolic extracts, their fractions, and isolated ecdysteroids were studied against pathogenic Acanthamoeba castellani. Additionally, a Microtox^® acute toxicity assay was performed. It was found that an 80% methanolic fraction of root extract exerts the most potent amoebicidal activity at IC₅₀ of 0.06 mg/mL at the 3rd day of treatment. Both ecdysteroids show comparable activity at IC₅₀ of 0.07 mg/mL. The acute toxicity of 80% fractions at similar concentrations is significantly higher than that of 40% fractions. Crude extracts exhibited moderate antifungal activity, with a minimum inhibitory concentration (MIC) within the range of 1.25–2.5 mg/mL. To the best of our knowledge, the present report is the first to show the biological activity of L. flos-cuculi in terms of the antifungal and antiamoebic activities and acute toxicity. It is also the first isolation of the main ecdysteroids from L. flos-cuculi micropropagated, ecdysteroid-rich plant material.     

Thiophene derivatives with antileishmanial activity isolated from aerial parts of Porophyllum ruderale (Jacq.) Cass

Porophyllum ruderale (Jacq.) Cass. is a plant native to Brazil and in the northwest region of the state of Paraná, Brazil, aerial parts of P. ruderale have been used popularly in the treatment of lesions caused by Leishmania sp.. In this study the antileishmanial and cytotoxic activities of the crude extract, fractions, and isolated compounds from aerial parts of P. ruderale was evaluated. The dichloromethane extract was submitted to chromatography to yield compounds active against Leishmania amazonensis. Their structures were established by comparison of their spectroscopic data with literature values. The activities of crude extract against promastigote and axenic amastigote forms of L. amazonensis (IC(50)) were 60.3 and 77.7 μg/mL, respectively. Its cytotoxic activity against macrophage cells (CC(50)) was 500 μg/mL. The thiophene derivatives isolated were: 5-methyl-2,2':5',2"-terthiophene (compound A) and 5'-methyl-[5-(4-acetoxy-1-butynyl)]-2,2'-bithiophene (compound B). The activity of compound A against promastigote and axenic amastigote forms were 7.7 and 19.0 μg/mL and of compound B were 21.3 and 28.7 μg/mL, respectively. The activity of the isolated compounds against promastigote and axenic amastigote forms was better than that of the crude extract and more selective against protozoa than for macrophage cells.     

An HPLC‐UV method for determining plasma dimethylacetamide concentrations in patients receiving intravenous busulfan

Dimethylacetamide (DMA) is a solvent used in the preparation of intravenous busulfan, an alkylating agent used in blood or marrow transplantation. DMA may contribute to hepatic toxicity, so it is important to monitor its clearance. The aim of this study was to develop an HPLC‐UV assay for measurement of DMA in human plasma. After precipitation of plasma proteins with acetonitrile followed by dilution (1:4) with water, the extract was injected onto the HPLC and detected at 195 nm. Separation was performed using a Cogent‐HPS 5 μm C₁₈ column (250 × 4.6 mm) preceded by a Brownlee 7 μm RP₁₈, pre‐column (1.5 cm × 3.2 mm). The mobile phase was 25 mm sodium phosphate buffer (pH 3), containing 2.5% (v /v) acetonitrile and 0.0005% (v /v) sodium‐octyl‐sulfonate. Using a flow rate of 1 mL/min, the retention times of DMA and the internal standard (IS), 2‐chloroacetamide, were 9.5 and 3.5 min, respectively. Peak area ratio (DMA:IS) was a linear function of concentration from 1 to 1000 μg/mL. There was excellent intraday precision (<5% for 5–700 μg/mL DMA), accuracy (<3% deviation from the true concentration) and recovery (74–98%). The limits of detection and quantification were 1 and 5 μg/mL, respectively. In eight children who received intravenous busulfan, DMA concentrations ranged from 110 to 438 μg/mL.     

Synthesis, characterization, and antimicrobial evaluation of oxadiazole congeners

A series of 1,3-oxazole, 1,3-thiazole, isomeric 1,2,4-oxadiazole, 1,3,4-oxadiazole, and 1,2,3,4-tetrazole heterocycles was synthesized. All the compounds shared as a common feature the presence of a 4-hydroxyphenyl substituent. The structures of the synthesized compounds were confirmed by MS, 1H-NMR, and elemental analysis. In vitro antimicrobial activity for all the newly synthesized compounds at concentrations of 200-25 μg/mL was evaluated against Gram+ve organisms such as methicillin-resistant Staphylococcus aureus (MRSA), Gram-ve organisms such as Escherichia coli (E. coli), and the fungal strain Aspergillus niger (A. niger) by the cup plate method. Ofloxacin and ketoconazole (10 μg/mL) were used as reference standards for antibacterial and antifungal activity, respectively. Compounds 15, 16, and 20 showed notable antibacterial and antifungal activities at higher concentrations (200 μg/mL), whereas 17-19 were found to display significant antibacterial or antifungal activity (25-50 μg/mL) against the Gram+ve, Gram-ve bacteria, or fungal cells used in the present study.     

Two new tetralone derivatives from the culture of Xylaria hypoxylon AT-028

Two new tetralone derivatives named xylariol A （1） and B （2） were isolated from the EtOAc extract of the culture broth of Xylaria hypoxylon AT-028 （Xylariaceae）, and their structures were elucidated by MS, 1R, 1D- and 2D-NMR spectra, and by X-ray diffraction analysis. 1 and 2 showed moderate cytotoxic activities against Hep G2 cells in the in vitro cytotoxic assay with IC50 values of 22.3 and 21.2 μg/mL, respectively.     

Design,synthesis, and antifungal evaluation of novel coumarin-pyrrole hybrids

A series of coumarin derivatives bearing a pyrrole scaffold were designed, prepared, and assessed for their in vitro antifungal activities against six phytopathogenic fungi. The antifungal activity screening results suggest that some synthesized hybrids exhibited potential fungicidal activities against the tested fungi. In particular, compounds 6j , 6k , 6o , 6p , and 6r displayed significant antifungal effects against Rhizoctorzia solani, and possessed EC₅₀ values of 3.94, 7.75, 6.38, 6.25, and 7.67 μg/ mL, respectively. The above activities are more potent than the commercialized fungicide Boscalid (11.52 μg/mL) and Osthole (9.79 μg/mL). These results provide a significant reference for further rational design of coumarin-based fungicides.     

Antifungal activity, toxicity and chemical composition of the essential oil of Coriandrum sativum L. fruits

The aims of this study were to test the antifungal activity, toxicity and chemical composition of essential oil from C. sativum L. fruits. The essential oil, obtained by hydro-distillation, was analyzed by gas chromatography/mass spectroscopy. Linalool was the main constituent (58.22%). The oil was considered bioactive, showing an LC?? value of 23 μg/mL in the Artemia salina lethality test. The antifungal activity was evaluated against Microsporum canis and Candida spp. by the agar-well diffusion method and the minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) were established by the broth microdilution method. The essential oil induced growth inhibition zones of 28 ± 5.42 and 9.25 ± 0.5 for M. canis and Candida spp. respectively. The MICs and MFCs for M. canis strains ranged from 78 to 620 and 150 to 1,250 μg/mL, and the MICs and MFCs for Candida spp strains ranged from 310 to 620 and 620 to 1,250 μg/mL, respectively. C. sativum essential oil is active in vitro against M. canis and Candida spp. demonstrating good antifungal activity.     

Chemical composition, anti-inflammatory, molluscicidal and free-radical scavenging activities of the leaves of Ficus radicans 'Variegata' (Moraceae)

The methanol crude extract of the leaves of Ficus radicans Roxb. 'Variegata' (Moraceae) and the n-hexane, ethyl acetate and aqueous methanol fractions resulting from its fractionation were evaluated for their anti-inflammatory, molluscicidal and free-radical scavenging activities. The crude extract and fractions exhibited significant inhibition of inflammation in both croton oil (CO)-induced ear oedema in mice (p<0.001) and carrageenan-induced rat paw oedema models (p<0.01). The molluscicidal assay against Biomphalaria glabrata showed a weak activity for the n-hexane fraction (DL(50)=?400 μg mL(-1)). A moderated 1,1-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging activity was observed for the ethyl acetate fraction (IC(50)=?66.2 μg mL(-1)). Fractionation of the extracts through chromatographic methods afforded the coumarins 7-methoxycoumarin, 7-hydroxy-6-methoxycoumarin and methoxy-3,4-dihydrocoumarin, the steroids β-sitosterol and β-sitosterol 3-O-β-glucopyranoside, as well as a cinnamic acid derivative and a flavonoid identified as trans-4-methoxy-2-β-D-glucopyranosyloxy cinnamic acid and quercetin 3-O-β-D-xylopyranosyl-(1?→?2)-α-L-rhamnopyranoside, respectively. The compounds were identified on the basis of their NMR spectral data and comparison with those previously reported in the literature.     

Phytofabrication of silver nanoparticles from Limonia acidissima leaf extract and their antimicrobial,antioxidant and its anticancer prophecy

Green synthesis of nanoparticles by eco-friendly methods is a recent technique which draws the attention of researchers because of the reward over many conventional chemical methods. The present work focuses on aqueous Limonia acidissima leaf extract in synthesizing silver nanoparticles and its applications in a simple way. The silver nanoparticles formed were characterized by Infrared, Ultra violet-visible, X-ray diffraction, transmission electron microscopic, and atomic force microscopic techniques. The powder X-ray diffraction studies and transmission electron microscopic images reveal that the silver nanoparticles synthesized were approximately 10–40 nm and have a spherical structure. The nanoparticles were assayed for their antibacterial, antifungal and antioxidant activity. The antimicrobial studies for the silver nanoparticles show a maximum zone of inhibition of 8.8 mm for Bacillus subtilis bacteria and 8.5 mm for Candida albicans fungi at 3 and 1 μg/mL respectively. In-silico ADMET studies reveal that the toxicity, bioactivity, pharmacokinetics and drug-likeness properties of Limonia acidissima leaf extract is good. The molecular docking studies show that the microbial activity is high for Bacillus subtilis and Candida albicans showing the coincidence of the in silico and in vitro studies as expected. The free radical scavenging activity of nanoparticles is 80 for 100 μg/mL. The 50% of inhibition of silver nanoparticles against human breast cancer cell lines is 18 μg/mL. It is evident that silver nanoparticles would be helpful in treating cancer cell lines and have great perspectives in the biomedical sector.     

In vitro wound healing properties,antioxidant activities,HPLC–ESI–MS/MS profile and phytoconstituents of the stem aqueous methanolic extract of Dracaena reflexa Lam

Column chromatography of the stem aqueous methanolic extract of Dracaena reflexa Lam. (DRSE) led to the isolation of five flavonoids, one phenolic glycoside, one triterpenoid and two steroidal saponins. Furthermore, 44 compounds were tentatively identified in the phytoconstituent profile of DRSE using HPLC–ESI–MS/MS. The antioxidant activity of DRSE was evaluated. In a DPPH radical scavenging assay, DRSE exhibited an IC₅₀ value of 311.6 ± 10.10 μg/ml compared with the IC₅₀ value of the standard Trolox (24.42 ± 0.87 μg/ml). The antioxidant activities of DRSE using ABTS assay and ferric reducing antioxidant power assay were 326.63 μm Trolox equivalents/mg extract and 208.67 μm Trolox equivalents/mg extract, respectively. The wound-healing activity of DRSE was studied by the scratch assay using Human Skin Fibroblast cells. After 24 h DRSE (at 10 and 20 μg/ml) decreased the wound width to 0.55 ± 0.37 and 0.47 ± 0.55 mm, respectively, compared with the wound width in the control cells (0.77 ± 0.17 mm). This result suggested that DRSE improved the wound-healing process by inducing the migration of fibroblasts. Moreover, a docking study was performed to evaluate the binding affinity of the identified phytoconstituents toward GSK-3β relative to the co-crystalized inhibitor and curcumin with the possible involvement of this pathway in the wound-healing activity of the extract.     

Antimicrobial prospect of newly synthesized 1,3-thiazole derivatives

A new series of 1,3-thiazole and benzo[d]thiazole derivatives 10-15 has been developed, characterized, and evaluated for in vitro antimicrobial activity at concentrations of 25-200 μg/mL against Gram+ve organisms such as methicillin-resistant Staphylococcus aureus (MRSA), Gram-ve organisms such as Escherichia coli (E. coli), and the fungal strain Aspergillus niger (A. niger) by the cup plate method. Ofloxacin and ketoconazole (10 μg/mL) were used as reference standards for antibacterial and antifungal activity, respectively. Compounds 11 and 12 showed notable antibacterial and antifungal activities at higher concentrations (125-200 μg/mL), whereas benzo[d]thiazole derivatives 13 and 14 were found to display significant antibacterial or antifungal activity (50-75 μg/mL) against the Gram+ve, Gram-ve bacteria, or fungal cells used in the present study. In addition, a correlation between calculated and determined partition coefficient (log P) was established which allows future development of compounds within this series to be carried out based on calculated log P values. Moreover, compounds 13 and 14 show that the optimum logarithm of partition coefficient (log P) should be around 4.     

Acute toxicity evaluation, antibacterial, antioxidant and immunomodulatory effects of Melastoma malabathricum

Melastoma malabathricum (MM) is a well-known plant in Malaysian traditional medicine, locally known as senduduk. Its ethanol and aqueous extracts have been used in the present investigation to study the immunomodulatory role on human peripheral blood mononuclear cell (PBMC), and the DPPH, ABTS and FRAP free radical scavenging activities were also measured. Total flavonoids and total phenolic contents were assayed and the antibacterial effect was tested against four species of bacteria; two Gram-positive (Staphylococcus aureus and Streptococcus agalactiae) and two Gram-negative (Escherichia coli and Klebsilla pneumonia). The tests were carried out using the disc diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) methods. Moreover, the acute toxicity was evaluated in vivo on the ethanol extract of MM to establish its safety when administered orally. In our results, both extracts of MM showed abilities to scavenge DPPH and ABTS free radicals, IC(50) values: (11.599 ± 0.84, 10.573 ± 0.58 μmol/L) and (62.657 ± 0.78, 63.939 ± 0.48 μmol/L) for ethanol and aqueous extracts respectively. Indeed the ethanol extract evidenced high phenolic content (384.33 ± 0.005 mg/g), flavonoids contents (85.8 ± 0.009 mg/g) and ferric reducing antioxidant power (33,590 ± 0.038 mmol/g), with high activity against S. aureus and S. agalactiae (11 ± 0.3 and 12 ± 0.6 mm inhibition zones). Likewise, the percentage of peripheral blood mononuclear cells (PBMC) viability was increased in response to MM, IC(50) values (1.781 ± 1.2 and 6.545 ± 0.93 μg/mL) for ethanol and aqueous extracts, respectively. In addition, our results showed that the MM extract is safe even at a high dose of 5,000 mg/kg and has no oral toxicity. These findings suggest the excellent medicinal bioactivity of MM and explain the popularity of this plant in the folk medicine as a remedy for different illnesses.     

Phenolic glucosides and chromane analogs from the insect fungus Conoideocrella krungchingensis BCC53666

Six new compounds, named conoideoglucosides A − C and conoideochromanes A − C, together with eight known compounds, including eutypinic acid, 2,2-dimethyl-2H-1-chromene-6-carboxylic acid, (−)-luteoskyrin, (−)-4a-oxyluteoskyrin, chrysophanol, islandicin, catenarin, and (22E)-5α,8α-epidioxyergosta-6,22-dien-3β-ol were isolated from the insect fungus Conoideocrella krungchingensis BCC53666. (−)-Luteoskyrin exhibited a broad range of antimicrobial activity such as antimalarial (IC₅₀ 0.51 μg/mL), antitubercular (MIC 6.25 μg/mL), antibacterial (both Gram positive; MIC 0.39–1.56 μg/mL and Gram negative; MIC 3.13–12.50 μg/mL), and antifungal (against various plant pathogens; MIC 3.13–50.00 μg/mL) activities, while (−)-4a-oxyluteoskyrin and catenarin showed weaker antibacterial activity. Moreover, eutypinic acid, (−)-luteoskyrin, (−)-4a-oxyluteoskyrin, and catenarin showed cytotoxicity against NCI-H187 cells with IC₅₀ in a range of 0.16–17.99 μg/mL, while eutypinic acid and catenarin had no cytotoxicity against non-cancerous (Vero) cells at maximum tested concentration (50 μg/mL). The complete NMR spectral data and biological activity of the known (−)-4a-oxyluteoskyrin was also reported for the first time.     

Fermentation of Korean Red Ginseng by Lactobacillus plantarum M-2 and Its Immunological Activities

We investigated ginsenoside transformation by fermentation of red ginseng with Lactobacillus plantarum M-2. We also examined the anti-metastasis and immune-stimulating activities of EtOH extracts of fermented red ginseng (FRG-E) in animal and human subjects. Total sugar decreased from 85.5 mg mL(-1) to 44.1 mg mL(-1) with increasing culture time during the fermentation with L. plantarum M-2. Uronic acid content reached a maximum level (534.3 μg mL(-1)) at 3 days of fermentation and decreased thereafter. Ginsenoside metabolites increased from 4,637.0 to 7,581.1 μg mL(-1) after 4 days. The prophylactic intraperitoneal injection of FRG-E (500 μg mouse(-1)) inhibited lung metastasis about 81.1%, while the inhibitory effect against tumor metastasis by treatment of EtOH extract from non-fermented red ginseng (NFRG-E) was 66.9%. Immunoglobulin A (IgA) and G (IgG) levels in the serum of healthy subjects were higher after FRG-E administration than at baseline, whereas NFRG-E induced reductions of these variables related to immunity. At 1 week, the change in IgA level by FRG-E (5.14 mg mL(-1)) was significantly higher than that by NFRG-E (-14.50 mg mL(-1); p < 0.05). It was concluded that the immunological activities of FRG-E were higher than those of NFRG-E, indicating that fermentation helped enhance the immunological activities of red ginseng.     

Effect of Extraction Method on Total Flavonoid,Total Phenolic Content,Antioxidant and Anti-bacterial Activity of Zingiberis Officinale Rhizome

This research aims to compare between decocta and maceration method using water and ethanol as a solvent on total flavonoid, total phenolic content, antioxidant and antibacterial activity of Zingiber officinale rhyzome extract. The Rhyzome was dryed by oven method on 50 °C for 24 hours and 48 hours. Total flavonoid, total phenolic content and antioxidant activity were assay by spectrophotometric method. The antibacterial activity was determined by difussion agar method against Bacillus subtilis (Bs) and Escherichia colli InaCC B5 (Ec). Ethanol extract from dried rhyzome processed for 24 hours (R-24) indicated the best result for total flavonoid, total phenolic content and antioxidant activity. The yield of total flavonoid for R-24 was 286 μg/mL. The yield of total phenolic content for R-24 was 504 μg/mL and the yield of IC₅₀ antioxidant activity for R-24 was 5.753 μg/mL. The extract should antibacterial activity againts Bs with inhibition diameter of 10% and 20% of samples concentration are 10 and 11.5 mm respectively. Meanwhile, The inhibition diameter result against Ec for 10% and 20% of samples concentration are 7.5 and 8.5 mm respectively.     

Inhibitory activity of dihydrosanguinarine and dihydrochelerythrine against phytopathogenic fungi

The antifungal activities of dihydrosanguinarine and dihydrochelerythrine, isolated from the leaves of Macleaya microcarpa, were evaluated on 12 plant pathogenic fungi; the two compounds exhibited the highest antifungal activity against Botrytis cinerea Pers. Among the 11 tested plant pathogenic fungi in vitro, the two compounds showed the highest antifungal activity against B. cinerea Pers, with 95.16% and 98.32% mycelial growth inhibition at 50 μg mL?1, respectively. In addition, the two compounds inhibited spore germination in vitro in a concentration-dependent manner. They also showed potent protective and curative effects against Erysiphe graminis and B. cinerea in vivo. This is the first report on the antifungal activity of dihydrosanguinarine and dihydrochelerythrine against pathogenic plant fungi.     

Anti-Helicobacter pylori Activity of Artemisia ludoviciana subsp. mexicana and Two of Its Bioactive Components,Estafiatin and Eupatilin

Artemisia ludoviciana subsp. mexicana has been traditionally used for the treatment of digestive ailments such as gastritis, whose main etiological agent is Helicobacter pylori. In a previous screening study, the aqueous extract exhibited a good in vitro anti-H. pylori activity. With the aim of determining the efficacy of this species as a treatment for H. pylori related diseases and finding bioactive compounds, its aqueous extract was subjected to solvent partitioning and the fractions obtained were tested for their in vitro anti-H. pylori effect, as well as for their in vivo gastroprotective and anti-inflammatory activities. The aqueous extract showed a MIC = 250 µg/mL. No acute toxicity was induced in mice. A gastroprotection of 69.8 ± 3.8%, as well as anti-inflammatory effects of 47.6 ± 12.4% and 38.8 ± 10.2% (by oral and topical administration, respectively), were attained. Estafiatin and eupatilin were isolated and exhibited anti-H. pylori activity with MBCs of 15.6 and 31.2 µg/mL, respectively. The finding that A. ludoviciana aqueous extract has significant anti-H. pylori, gastroprotective and anti-inflammatory activities is a relevant contribution to the ethnopharmacological knowledge of this species. This work is the first report about the in vivo gastroprotective activity of A. ludoviciana and the anti-H. pylori activity of eupatilin and estafiatin.     

Antilymphoma Effect of Incomptine A: In Vivo,In Silico,and Toxicological Studies

Incomptine A (IA) is a sesquiterpene lactone isolated from Decachaeta incompta that induces apoptosis, reactive oxygen species production, and a differential protein expression on the U-937 (diffuse histiocytic lymphoma) cell line. In this work, the antitumor potential of IA was investigated on Balb/c mice inoculated with U-937 cells and through the brine shrimp lethality (BSL) test. Furthermore, IA was subjected to molecular docking study using as targets proteins associated with processes of cancer as apoptosis, oxidative stress, and glycolytic metabolism. In addition to determining the potential toxicity of IA in human, its acute toxicity was performed in mice. Results reveals that IA showed high antilymphoma activity and BSL with an EC₅₀ of 2.4 mg/kg and LC₅₀ 16.7 µg/mL, respectively. The molecular docking study revealed that IA has strong interaction on all targets used. In the acute oral toxicity, IA had a LD₅₀ of 149 mg/kg. The results showed that the activities of IA including antilymphoma activity, BSL, acute toxicity, and in silico interactions were close to the methotrexate, an anticancer drug used as positive control. These findings suggest that IA may serve as a candidate for the development of a new drug to combat lymphoma.