Engineering bi-layered skin-like nanopads with electrospun nanofibers and chitosan films for promoting fibroblast infiltration in tissue regeneration and wound healing.

This study presents an innovative bi-layered three-dimensional skin-like nanopad (SLN) engineered for skin tissue regeneration. The SLN integrates a mechanically supportive polycaprolactone nanofibrous layer with a functional chitosan hydrogel film, mimicking natural skin. Our SLN exhibits superior flexibility, with a maximum elongation of 751.71 ± 125 % and exceptional porosity of 95 ± 4.5 %, ensuring effective exudate management due to its high water uptake capacity (4393 ± 72 %). FTIR analysis confirmed a distinctive fiber-hydrogel network within the SLN, which serves as a barrier against Staphylococcus aureus and Pseudomonas aeruginosa infiltration. In vitro cell viability assays with the human fibroblast have consistently demonstrated that 3D bi-layered SLN enhances fibroblast attachment, infiltration, and proliferation by 150 ± 20 %. In vivo studies in a rat model demonstrated significantly faster wound closure, with 60 % on day 7 and 87 % on day 10, compared to the 30 % and 60 % in controls, highlighting the efficacy of SLN. By mimicking the architecture of native skin, this biomimetic bi-layered SLN scaffold provides flexibility and support while accelerating in vivo wound closure by promoting fibroblast proliferation and infiltration. Customizable in size, depth, and shape, the engineered SLN has emerged as a promising platform for advanced wound care and tissue engineering.

Pseudomonas aeruginosa Bacteriophages and Their Clinical Applications.

Antimicrobial resistance poses a serious risk to contemporary healthcare since it reduces the number of bacterial illnesses that may be treated with antibiotics, particularly for patients with long-term conditions like cystic fibrosis (CF). People with a genetic predisposition to CF often have recurrent bacterial infections in their lungs due to a buildup of sticky mucus, necessitating long-term antibiotic treatment. Pseudomonas aeruginosa infections are a major cause of CF lung illness, and P. aeruginosa airway isolates are frequently resistant to many antibiotics. Bacteriophages (also known as phages), viruses that infect bacteria, are a viable substitute for antimicrobials to treat P. aeruginosa infections in individuals with CF. Here, we reviewed the utilization of P. aeruginosa bacteriophages both in vivo and in vitro, as well as in the treatment of illnesses and diseases, and the outcomes of the latter.

Bacteriophages and Green Synthesized Zinc Oxide Nanoparticles in Combination Are Efficient against Biofilm Formation of Pseudomonas aeruginosa.

Bacteriophages (phages) are viruses that infect the bacteria within which their reproduction cycle takes place, a process that ends in the lysis and death of the bacterial cell. Some phages are also able to destroy bacterial biofilms. Due to increased antibiotics resistance, Pseudomonas aeruginosa, another biofilm-forming pathogen, is a problem in many parts of the world. Zinc oxide (ZnO) and other metal nanoparticles (NPs) are biologically active and also possess anti-biofilm properties. ZnO-NPs were prepared by the green synthesis method using orange peels. The vibrational peaks of the ZnO-NPs were analyzed using FTIR analysis, and their size and morphological properties were determined using scanning electron microscopy (SEM). The ability of the ZnO-NPs to reduce or eliminate P. aeruginosa biofilm alone or in combination with phages PB10 and PA19 was investigated. The P. aeruginosa cells were effectively killed in the preformed 48 h biofilms during a 24 h incubation with the ZnO-NP-phage combination, in comparison with the control or ZnO-NPs alone. The treatments on growing biofilms were most efficient in the final stages of biofilm development. All five treatment groups showed a significant biofilm reduction compared to the control group (p < 0.0001) at 48 h of incubation. The influence of the ZnO-NPs and phages on the quorum sensing system of P. aeruginosa was monitored by quantitative real-time PCR (qRT-PCR) of the autoinducer biosynthesis gene lasI. While the ZnO-NPs repressed the lasI gene transcription, the phages slightly activated it at 24 and 48 h of incubation. Also, the effect of the ZnO-NPs and phage PA19 on the viability of HFF2 cells was investigated and the results showed that the combination of NPs with PA19 reduced the toxic effect of ZnO-NPs and also stimulated the growth in normal cells.

N-Acetyl cysteine amide and cerium oxide nanoparticles as a drug delivery for ischemic stroke treatment: Inflammation and oxidative stress crosstalk.

BACKGROUND: Inflammation and oxidative stress crosstalk is involved in the ischemic stroke(IS) pathogenesis and the new therapeutic options should be offered based on the targets that are critical in the golden hour of IS. YKL-40 and total antioxidant capacity(TAC), the inflammation and oxidative stress biomarkers, provide us with clues for proper intervention targets. N-acetyl cysteine amide (NACA), a lipophilic antioxidant, with a nanoparticle-based drug delivery system is permeable enough to penetrate blood-brain barrier (BBB) and was proposed as a new treatment option for IS. In this study, we evaluated the YKL-40 and TAC levels in the sera of IS patients to elucidate the best intervention target. A rat tissue model is used to assess the NACA efficiency. The microbiology tests performed to figure out the potential NACA and antibiotics interactions. MATERIAL AND METHODS: The YKL-40 and TAC were measured in the serum of IS patients by ELISA and FRAP methods, respectively. The serum samples were obtained 12 h after the patient's admission and meantime other laboratory findings and NIHSS-based prognosis were recorded. In the animal study, the brain cortex, liver, kidney, adipose, and the heart of healthy rats were dissected and then incubated in DMEM cell culture media containing 50 micrograms/milliliter of nanoparticles; the nanoparticles were titanium dioxide nanoparticles (TiO2 NPs), copper oxide nanoparticles (CuO NPs) and cerium dioxide nanoparticles (CeO2 NPs). Olive oil and human serum albumin solution were exposed to the nanoparticles with and without NACA. TAC was measured in the supernatant culture media. With similar concentrations and settings, we evaluated the NACA, nanoparticle, and antibiotics interactions on pseudomonas aeruginosa. RESULTS: There was a nonparametric correlation between YKL-40 levels and post stroke serum TAC levels. Nonsmokers had higher YKL-40 and TAC levels than smokers. A new calculated variable, urea*lymphocyte/age, predicts a poor prognosis with an acceptable AUC (0.708). Exposing to the nanoparticles, the liver, kidney, and brain had a significantly higher TAC than adipose and cardiac tissue. The NACA had an ameliorative effect against TiO2 NPs in the brain. This effectiveness of NACA was also observed against CuO NPs treatment. However, the CeO2 NPs exert a strong antioxidant property by reducing the TAC in the brain tissue but not the others. Albumin showed antioxidant properties by itself, but olive oil had an inert behavior. NACA had no interaction with the action of routine antibiotics. CONCLUSION: Oxidative stress but not inflammation is the best point for intervention in IS patients because YKL-40 has not a relationship with NIHSS score. The CeO2 NPs and NACA combination are eligible option to develop antioxidant-based drug for the treatment of IS. As a complementary finding, the urea*lymphocyte/age is proposed as a NIHSS-based prognosis biomarker.

Design of Phage-Cocktail-Containing Hydrogel for the Treatment of Pseudomonas aeruginosa-Infected Wounds.

Recently, the treatment of infected wounds has become a global problem due to increased antibiotic resistance in bacteria. The Gram-negative opportunistic pathogen Pseudomonas aeruginosa is often present in chronic skin infections, and it has become a threat to public health as it is increasingly multidrug resistant. Due to this, new measures to enable treatment of infections are necessary. Treatment of bacterial infections with bacteriophages, known as phage therapy, has been in use for a century, and has potential with its antimicrobial effect. The main purpose of this study was to create a phage-containing wound dressing with the ability to prevent bacterial infection and rapid wound healing without side effects. Several phages against P. aeruginosa were isolated from wastewater, and two polyvalent phages were used to prepare a phage cocktail. The phage cocktail was loaded in a hydrogel composed of polymers of sodium alginate (SA) and carboxymethyl cellulose (CMC). To compare the antimicrobial effects, hydrogels containing phages, ciprofloxacin, or phages plus ciprofloxacin were produced, and hydrogels without either. The antimicrobial effect of these hydrogels was investigated in vitro and in vivo using an experimental mouse wound infection model. The wound-healing process in different mouse groups showed that phage-containing hydrogels and antibiotic-containing hydrogels have almost the same antimicrobial effect. However, in terms of wound healing and pathological process, the phage-containing hydrogels performed better than the antibiotic alone. The best performance was achieved with the phage-antibiotic hydrogel, indicating a synergistic effect between the phage cocktail and the antibiotic. In conclusion, phage-containing hydrogels eliminate efficiently P. aeruginosa in wounds and may be a proper option for treating infectious wounds.

In vitro study of redroot pigweed effects as weed plant species on leukemia.

Redroot pigweed is a well-known allelopathic weed worldwide with diverse organic compounds which involving in its allelopathic interactions as well. Preliminary tests of redroot pigweed extract against leukemia and various human phatogenic microorganisms revealed that amaranth extract inhibits the viability and proliferation of NB4 cells in a time- and dose-dependent manner and has an excellent anti-bacterial effect on gram-positive bacteria and Candida fungi. Interestingly, the anti-luekemia effects of redroot pigweed is reported for the first time. Phytochemical analysis of redroot pigweed extract, led to the identification amaranth bioactive compounds that largely were including terpenoid compounds (51.71%) as the main group and Carvacrol (11.33%) was the key compound. Redroot pigweed contains various organic compounds with allelopathic and therapeutic properties and current investigation is a promising revelation for the pharmaceutical importance of this plant.

Combination of zeolite barrier and bio sparging techniques to enhance efficiency of organic hydrocarbon remediation in a model of shallow groundwater.

Adsorption and bioremediation are effective processes for remediation of benzene, toluene, and ethylbenzene (BTE) through Permeable Reactive Barriers (PRBs). A few researches focus on adsorption of natural zeolite because of its hydrophilic property. On the other hand, PRBs need to be replaced by fresh materials after a while when all the possible absorption positions were filled up. We tried to find a way to increase the efficiency of PRB, elongation of its replacement period and of course decreasing the cost of remediation. Equipping of PRB with microbial degradation system was the idea. The present study describes the performances of natural Clinoptilolite-Heulandite Zeolite (CH-Z) and three new strains (safe and low-cost media) utilized in a PRB for removing BTE from contaminated shallow groundwater. First, batch tests were conducted to recognize the optimal removal conditions for utilization of C-HZ and strains to remediate BTE compounds. Then, an aerobic PRB system filled with a natural zeolite was designed and investigated in a continuous flow sand-tank model to assess the efficiency of combined PRBs (zeolite + biosparging), for BTE-contaminated groundwater. Batch experiments showed that the BTE removal of zeolite was 89%, as well as, a consortium of three bacterial strains, Variovorax sp. OT16, Pseudomonas balearica OT17, and Ornithinibacillus sp. OT18 efficiently removed the BTE mixture. The process of BTE removal in the PRB under continuous-flow condition was divided into three phases: Phase I, in which the barrier was made of the only zeolite, and in Phases II and III the reactor was fed by microorganisms. This experiment revealed that in Phases I, the concentrations of BTE decrease (92%) due to zeolite adsorption. In Phase II and III, the degradation process became the principal removal mechanism (68% and 81%, respectively). Consequently, this research showed high ability of C-HZ in the BTE treatment, and a combination of Natural Zeolite, with a biological degradation system (CH-Z -PRB) improves the efficiency of BTE remediation. However, the slow biodegradation rates and the continuous injection of BTE in the model confirmed that longer time was needed for the PRB to function optimally. Finally, the combined method of CH-Z- BIO PRB showed the great potential in the restriction of the BTE migration that can be used at the field-scale after up-scaling.

Lactobacillus casei UT1 Isolated from Northwest of Iran Traditional Curd Exerts Anti-proliferative and Apoptosis Inducing Effects in Human Colorectal Tumor HCT 116 Cells.

Purpose: The present study was mainly designed to assess anti-cancer effects of lactobacilli isolated from traditional dairy products, on HCT116 colorectal cancer cell lines. Methods: Traditional dairy products samples were collected from the region of Azarbayjan and the suspensions were cultured in MRS agar medium. The isolates were identified by biochemical and molecular methods. Isolated bacteria were cultured in MRS broth. Supernatants of the isolates cultures were collected and their cytotoxicity was evaluated on HCT116 cancer cells. Morphological changes of the treated cells by supernatant were observed using an inverted microscope. Cell metabolic activity was assessed by MTT assay. The morphology of apoptotic cells was examined using a fluorescent microscope. In cell cycle analysis, content measurement of DNA was performed by flow cytometry. Results: Out of 30 lactobacilli were isolated from dairy products samples, six isolates belong to curd samples. Cell-based assays showed that culture supernatant of one isolate (UT1) had a significant anticancer effect on colorectal HCT116 cell lines (P<0.05). The 16S rRNA sequence analysis revealed that the isolate UT1 was 99% compatible with Lactobacillus casei. Conclusion: It is noteworthy that the supernatant of L. casei UT1 can be candidate for studies on compounds having anti-cancer effect.

ZnO, AgCl and AgCl/ZnO nanocomposites incorporated chitosan in the form of hydrogel beads for photocatalytic degradation of MB, E. coli and S. aureus.

Significant improvement of effective and low-cost decolorization and disinfecting technologies is required to address the problems created by dyes and dangerous microorganisms from water and wastewaters. This article expresses the degradation of methylene blue (MB), Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) as gram negative and positive bacteria via a chitosan/AgCl/ZnO (CS/AgCl/ZnO) nanocomposite hydrogel beads system as a photocatalyst under visible light irradiation. The techniques such as FT-IR, SEM, EDAX, TGA, and XRD were applied to recognize the synthesized beads. Decolorization and disinfection experimental results revealed that the hydrogel beads system effectively degrade MB and bacteria. Also, the effects of the initial amount of catalysts, pH, coions and initial concentration of dye on the photocatalytic decolorization were investigated. Moreover, kinetics analysis indicates that the photocatalytic degradation rate of MB and bacteria can be described by Langmuir-Hinshelwood (L-H) and Weibull inactivation models, respectively. We provide a reusable and recoverable effective organic/inorganic photocatalyst in the form of beads that could solve the disadvantages of powder photocatalytic, without reducing the efficiency.

In Silico Identification of Probable Drug and Vaccine Candidates Against Antibiotic-Resistant Acinetobacter baumannii.

Acinetobacter baumannii is known as a Gram-negative bacterium that has become one of the most important health problems due to antibiotic resistance. Today, numerous efforts are being made to find new antibiotics against this nosocomial pathogen. As an alternative solution, finding bacterial target(s), necessary for survival and spread of most resistant strains, can be a benefit exploited in drug and vaccine design. In this study, a list of extensive drug-resistant and carbapenem-resistant (multidrug resistant) A. bumannii strains with complete sequencing of genome were prepared and common hypothetical proteins (HPs) composed of more than 200 amino acids were selected. Then, a number of bioinformatics tools were combined for functional assignments of HPs using their sequence. Overall, among 18 in silico investigated proteins, the results showed that 7 proteins implicated in transcriptional regulation, pilus assembly, protein catabolism, fatty acid biosynthesis, adhesion, urea catalysis, and hydrolysis of phosphate monoesters have theoretical potential of involvement in successful survival and pathogenesis of A. baumannii. In addition, immunological analyses with prediction softwares indicated 4 HPs to be probable vaccine candidates. The outcome of this work will be helpful to find novel vaccine design candidates and therapeutic targets for A. baumannii through experimental investigations.

Design, synthesis and evaluation of biological activities of some novel anti-TB agents with bio-reducible functional group.

Introduction: With regard to the anti-mycobacterial activity of 2-pyrazinoic acid esters (POEs), recent studies have shown that both pyrazine core and alkyl part of POE interact with the fatty acid synthase type (I) (FAS (I)) precluding a complex formation between NADPH and FAS (I). Methods: Considering this interaction at the reductase site of FAS (I) responsible for reduction of ß-ketoacyl-CoA to ß-hydroxyacyl-CoA, we hypothesized that POE containing a bioreducible center in its alkyl part might show an increased anti-tubercular activity due to the involvement of FAS (I) in extra bio-reduction reaction. Thus, we synthesized novel POEs, confirmed their structures by spectral data, and subsequently evaluated their anti-mycobacterial activity against Mycobacterium tuberculosis (Mtb) (H37Rv) strain at 10 µg/mL concentration. Results: Compounds 3c, 3j, and 3m showed higher activity with regard to the inhibition of Mtb growth by 45.4, 45.7, and 51.2% respectively. Unexpectedly, the maltol derived POE 3l having the lowest log p value among the POEs indicated the highest anti-mycobacterial growth activity with 56% prevention. Compounds 3c and 3l showed no remarkable cytotoxicity on human macrophages at 10 µg/mL concentration as analyzed by xCELLigence real-time cell analysis. In further experiments, some of the tested POEs, unlike pyrazinamide (PZA), exhibited significant antibacterial and also anti-fungal activities. POEs showed an enhanced bactericidal activity on gram-positive bacteria as shown for Staphylococcus aureus , e.g. compound 3b with a MIC value of 125 µg/mL but not E. coli as a gram-negative bacteria, except for maltol derived POE (3l) that showed an inverse activity in the susceptibility test. In the anticancer activity test against the human leukemia K562 cell lines using MTT assay, compounds 3e and 3j showed the highest cytotoxic effect with IC50 values of 25±8.0 µΜ and 25±5.0 µΜ, respectively. Conclusion: It was found that the majority of POEs containing a bioreducible center showed higher inhibitory activities on Mtb growth when compared to the similar compounds without a bio-reducible functional group.

Vancomycin Capped with Silver Nanoparticles as an Antibacterial Agent against Multi-Drug Resistance Bacteria.

Purpose: Many antimicrobial medications are available to combat infections. However, the indiscriminate use of antibiotics has produced antibiotic resistance in the case of many bacterial pathogens. This study focuses on the development of nanoparticles (NPs) that enhance the in vitro antibiotic activity of vancomycin against multi-drug resistant (MDR) organisms. Methods: Spherical shaped thioglycolic acid-stabilized silver nanoparticles (TGA-AgNPs) were prepared by using a simple chemical reduction method. Then, vancomycin was conjugated to the terminal carboxyl of TGA in the presence of N-Hydroxysuccinimide (NHS) and N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC). Afterwards, the antibacterial activity of these nanoconjugates was examined by using the minimum inhibitory concentration (MIC) assay against MDR bacteria. Results: The rate of vancomycin bound to the AgNPs was 19.6%. The MIC values of vancomycin (Van)-capped AgNPs against tested pathogens were in the range of (3.2, 1.6, 0.8, 0.4, 0.2, 0.1, 0.05, and 0.025 µl/ml). The MIC was 0.1 µg/ml for VRE, MIC≤0.02 µg/ml for MRSE, and 0.05 µg/ml for S. aureus. The MIC corresponded to the MBC for all bacterial species. Conclusion: This study indicated that some antimicrobial agents like vancomycin can be conjugated with AgNPs. This can lead to increased antimicrobial activity against MDR microorganisms.

Novel functionalized monomers based on kojic acid: snythesis, characterization, polymerization and evalution of antimicrobial activity.

Two novel acrylate monomers, [5-(benzyloxy)-4-oxo-4H-pyran-2-yl]methyl acrylate and {1-[(5-(benzyloxy)-4-oxo-4H-pyran-2-yl)methyl]-1,2,3-triazol-4-yl}methyl acrylate were synthesized by the reaction of 5-benzyloxy-2-(hydroxymethyl)-4H-pyran-4-one and 5-(benzyloxy)-2-{[4-(hydroxymethyl)-1,2,3-triazol-1-yl]methyl}-4H-pyran-4-one with acryloyl chloride in the presence of triethylamine, respectively. These monomers were polymerized using 2,2'-azobisisobutyronitrile (AIBN) as the initiator in N,N-dimethylformamide:14-dioxane (10:1) solution. The thermal behavior of the polymers was investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The synthesized compounds were evaluated for their antibacterial and antifungal activites aganist bacteria and fungi using the disk diffusion method. The results indicated that some of these compounds demonstrated moderate to good antibacterial and antifungal activities.

Plasma surface modification as a new approach to protect urinary catheter against Escherichia coli biofilm formation.

BACKGROUND AND OBJECTIVES: Biomaterials are widely used in medical devices such as urinary catheters. One of the main problems associated with long term using of the urinary catheters is biofilm formation on their surfaces. Many techniques have been presented to reduce the biofilm formation. One of the most revolutionary techniques allowing such surface fictionalization is plasma surface modification. MATERIALS AND METHODS: In this study, a glow discharge plasma (GDP) effect on Escherichia coli biofilm formation on the surface of urinary catheter in the pressure of 1.6 × 10-1 Torr of nitrogen, discharge voltage about 1.2 kV and current of 150 mA for 20 minutes has been investigated. Crystal violet binding assay and sonication method were performed in order to evaluate the amount of biofilm formation on tested biomaterials. RESULTS: Characterization of modified surfaces by Attenuated Total Reflectance Fourier Transform Infrared Spectrometry (ATR-FTIR) and atomic force microscopy (AFM) revealed a noticeable change in hydrophobicity and roughness of catheter surfaces achieved by nitrogen plasma. The results of crystal violet binding assay and sonication method showed that the amount of biofilm formation on modified surface was about 86% less than the pristine sample. CONCLUSION: Plasma surface modification can reduce the risk of infections in patients with long-term use of urinary catheters.

Effective Phages as Green Antimicrobial Agents Against Antibiotic-Resistant Hospital Escherichia coli.

BACKGROUND: Bacteriophages are viruses that attack bacteria and lead to their lysis in an efficient and highly specific manner. These natural enemies of bacteria were used as therapeutic agents before the advent of antibiotics. Currently, with the rapid spread of multi-drug resistant bacteria, phage therapy can be an effective alternative treatment for antibiotic resistant bacteria. OBJECTIVES: This study evaluated the effectiveness of bacteriophages in removing antibiotic-resistant clinical Escherichia coli strains in vitro and in vivo. PATIENTS AND METHODS: Different samples were taken from bed sore and foot ulcers of patients with diabetes. E. coli strains were isolated and identified by standard methods. The antibiogram was ascertained using the Kirby Bauer disc diffusion method for ten antibiotics. The bacteriophages were isolated from environmental water samples. They were exposed to the host bacteria by the double-layer agar technique (DLA) to observe plaques. Cross reaction of the phages on test E. coli strains was performed to determine broader-spectrum phages. Phage TPR7 was selected for animal trials. Five groups of mice including a control group, bacterial group, phage group, antibiotic therapy group and phage therapy group, were examined. RESULTS: Ten E. coli strains were isolated from hospital samples. They showed high resistance to the used antibiotics. An effective bacteriophage was isolated for each strain. The cross-reaction showed phages which affect more than six E. coli strains. They can be a good choice for clinical therapeutic use. In animal trials the group challenged with phages after being infected showed similar results as the group treated with gentamicin after being infected. In both groups infection was removed after 48 hours. CONCLUSIONS: According to the results, six strains were resistant to six or seven antibiotics and all strains were at least resistant to two antibiotics. However, for each of these resistant bacteria one bacteriophage was isolated from environmental samples, which showed the effectiveness of bacteriophages to remove clinically resistant E. coli strains. Effective phages in vitro showed effective results in vivo as well.

Halotolerant Ability and α-Amylase Activity of Some Saltwater Fungal Isolates.

Four halotolerant fungal isolates originating from the saltwater Lake Urmia in Iran were selected during a screening program for salt resistance and α-amylase activity. The isolates were identified based on sequencing the ITS region and a part of the ß-tubulin gene, as Penicillium chrysogenum (isolate U1; CBS 132820), Fusarium incarnatum (isolate U2; CBS 132821), and Penicillium polonicum (isolate U3; CBS 132822, and isolate U4; CBS 132823). The growth of these isolates was determined by measuring the colony diameter and mycelia dry weight in Sabouraud dextrose agar and yeast nitrogen base medium supplemented with NaCl, KCl, and LiCl. Isolate U4 showed a growth up in 15% NaCl and U1 was the only isolate that could grow in 20% KCl. None of the strains grew in a media containing LiCl. The salt supplemented medium did not increase the size of colony diameter in all isolates (p > 0.05). The ability of the selected isolates for amylase production was quantitatively tested and showed that P. polonicum isolate U4 was the most potent producer of amylase with a yield of 260.9 U/L after 60 h, whereas P. polonicum isolate U3 was the lowest one with a production level of 97.9 U/L after 48 h. P. polonicum isolate U4 could be a suitable candidate for production of amylase on an industrial scale after optimization.

Pyranocoumarins from Zosima absinthifolia (Vent) Link roots.

Zosima absinthifolia (Vent) Link (Apiaceae) is a perennial herb indigenous to Iran. It has been used as a medicinal plant from ancient time in Iran, Turkey and Pakistan. In the present work, air-dried and powdered plant roots were extracted with n-hexane, dichloromethane and methanol, respectively, using Soxhlet apparatus. The dichloromethane extract was subjected to vacuum liquid chromatography (VLC) and preparative thin layer chromatography (P-TLC) to yield two pyranocoumarins, aegelinol and agasyllin. The antimicrobial assay was performed using agar dilution method. The results showed that purified compounds have modest to weak antibacterial and antifungal activity.

Biochemical characterization of an extracellular polyextremophilic α-amylase from the halophilic archaeon Halorubrum xinjiangense.

An extracellular haloalkaliphilic thermostable α-amylase producing archaeon was isolated from the saltwater Lake Urmia and identified as Halorubrum xinjiangense on the basis of morphological, biochemical, and molecular properties. The enzyme was purified to an electrophoretically homogenous state by 80 % cold ethanol precipitation, followed by affinity chromatography. The concentrated pure amylase was eluted as a single peak on fast protein liquid chromatography. The molecular mass of the purified enzyme was about 60 kDa, with a pI value of 4.5. Maximum amylase activity was at 4 M NaCl or 4.5 M KCl, 70 °C, and pH 8.5. The K m and V max of the enzyme were determined as 3.8 mg ml(-1) and 12.4 U mg(-1), respectively. The pure amylase was stable in the presence of SDS, detergents, and organic solvents. In addition, the enzyme (20 U) hydrolyzed 69 % of the wheat starch after a 2-h incubation at 70 °C in an aqueous/hexadecane two-phase system.

Isoarnottinin 4'-glucoside, a glycosylated coumarin from Prangos uloptera, with biological activity.

Coumarins are a well-known group of natural products distributed in the plant kingdom especially in the family Apiaceae with various biological activities. Isoarnottinin 4'-glucoside is a simple glycosylated coumarin found previously in a few genera of Apiaceae, and its biological activities have not been previously described in details. In the present paper, the compound was isolated from Prangos uloptera (Apiaceae) leaves using HPLC techniques. Antimicrobial, phytotoxic and cytotoxic activities of the compound were evaluated by disk diffusion, lettuce assay and MTT method. Our results indicated that the compound has high antibacterial effect against Erwinia carotovora, a common plant pathogen with MIC value of 100 microg/mL. The compound also exhibited significant phytotoxic activity against lettuce and modest cytotoxic activity against HeLa cell line with IC50 of 0 .84 mg/mL. It could be concluded that isoamottinin 4'-glucoside may play phytoalexin or allelopathic role for plant and may be a candidate for an antibacterial agent or a bioherbicide.

Bioactivity of malva sylvestris L., a medicinal plant from iran.

OBJECTIVES: Malva sylvestris L. (Malvaceae), an annual plant, has been already commonly used as a medicinal plant in Iran. In the present work, we evaluate some bioactivities of the plant extracts. MATERIALS AND METHODS: The aired-dried plant flowers and leaves were extracted by soxhlet apparatus with n-hexane, dichloromethane and methanol. The antimicrobial, cytotoxic, and phytotoxic of the plant extracts were evaluated using disk diffusion method, MTT, and Lettuce assays, respectively. RESULTS: Both flowers and leaves of M. sylvestris methanol extracts exhibited strong antibacterial effects against Erwinia carotovora, a plant pathogen, with MIC value of 128 and 256 µg/ml, respectively. The flowers extract also showed high antibacterial effects against some human pathogen bacteria strains such as Staphylococcus aureus, Streptococcus agalactiae, Entrococcus faecalis, with MIC value of 192, 200 and 256 µg/ml, respectively. The plant methanol extracts had relatively high cytotoxic activity against MacCoy cell line. CONCLUSION: We concluded that Malva sylvestris can be candidated as an antiseptic, a chemopreventive or a chemotherapeutic agent.