Highest Antimicrobial Effect Research Articles

Investigation of potential use of by‐products from cold‐press industry as natural fat replacers and functional ingredients in a low‐fat salad dressing

In this study, the physicochemical, bioactive, antimicrobial, and fat replacer properties of by-products (black cumin seed [BOB], coconut [COB], flaxseed [FOB], and pumpkin seed [POB]) from the cold-press oil industry were investigated. The by-products were rich in protein, carbohydrate, and fiber contents. TPC (total phenolic content), CUPRAC (cupric reducing antioxidant capacity) values, in vitro bioaccessibility of phenolic compounds, and phenolic profile were analyzed to determine bioactive properties of by-products. FOB and BOB showed higher TPC and CUPRAC values and a higher antimicrobial effect, while phenolic compound diversity compared to other samples; therefore, they can be considered good bioactive sources. The steady and frequency sweep test rheological properties were conducted to determine the potential use of selected by-products as a fat replacer in low-fat salad dressing. The salad dressing samples enriched with by-products showed strong pseudoplastic and solid-like characteristics, except when enriched with 1% FOB and POB. This study suggests that by-products can be used in low-fat salad dressing as natural fat substitutes and functional ingredients. Novelty impact statement Cold-press oil processing results in a byproduct rich in protein, carbohydrate, and bioactive components. These by-products are suitable for food application, as no chemical treatment, such as solvent application, is applied during cold-press processing. The most important problem in the production of low-fat salad dressing is the less compact structure resulting from the reduction of fat. Protein- and carbohydrate-rich ingredients are used for the development of this structure. In addition, salad dressings are poor food groups in terms of bioactive components, and their bioactive properties should be improved. In this study, the comprehensive physicochemical and bioactive characterization, and potential use of these by-products in low-fat salad dressing as fat replacers were firstly investigated.

α-Terpinyl Acetate: Occurrence in Essential Oils Bearing Thymus pulegioides, Phytotoxicity, and Antimicrobial Effects.

The aim of this study was to evaluate occurrence of T. pulegioides α-terpinyl acetate chemotype, as source of natural origin α-terpinyl acetate, to determine its phytotoxic and antimicrobial features. Were investigated 131 T. pulegioides habitats. Essential oils were isolated by hydrodistillation and analyzed by GC-FID and GC-MS. Phytotoxic effect of essential oil of this chemotype on monocotyledons and dicotyledons through water and air was carried out in laboratory conditions; the broth microdilution method was used to screen essential oil effect against human pathogenic microorganisms. Results showed that α-terpinyl acetate was very rare compound in essential oil of T. pulegioides: it was found only in 35% of investigated T. pulegioides habitats. α-Terpinyl acetate (in essential oil and pure) demonstrated different behavior on investigated plants. Phytotoxic effect of α-terpinyl acetate was stronger on investigated monocotyledons than on dicotyledons. α-Terpinyl acetate essential oil inhibited seeds germination and radicles growth for high economic productivity forage grass monocotyledon Poa pratensis, but stimulated seed germination for high economic productive forage legume dicotyledon Trifolium pretense. α-Terpinyl acetate essential oil showed high antimicrobial effect against fungi and dermatophytes but lower effect against bacteria and Candida yeasts. Therefore, T. pulegioides α-terpinyl acetate chemotype could be a potential compound for developing preventive measures or/and drugs for mycosis.

Evaluation of the Antimicrobial Effect of the Extracts of the Pods of Piliostigma thonningii (Schumach.) Milne-Redh. (Fabaceae).

Plants have been used traditionally by people in treating and the management of diseases since time immemorial. Traditional medicines including the herbal medicines are used for primary healthcare in some domains in almost every country. Approximately 80% of the population in developing coutries depend on plants as their source of medicine for combating diseases. New and effective antimicrobial agents that have novel mechanism of actions are required. Piliostigma thonningii (Schumach.) Milne-Redh. is a species of flowering plants in the legume family, Fabaceae. Different parts of the P. thonningii plants such as the roots, leaves, seeds, and fruits have been used in treating wounds, heart pain, and gingivitis and as cough remedy. This study focused on determining the antimicrobial properties found in the pods of P. thonningii. The sample was prepared by grinding the dried pods into a fine powder. Successive extraction and extraction with 1 : 1 DCM: methanol was used. The antimicrobial assay was carried out using the broth microdilution and MTT assay. The microorganism used for the tests was Pseudomonas aeruginosa, Candida krusei and Mycobacterium smegmatis. The most potent extract was then used to determine its effect on microbial cell membrane integrity. The results showed that methanol extract had the highest percentage yield of 5%. The extract with the highest antimicrobial effects was ethanol extract with the 100 μg/mL concentration inhibiting the growth of cells to 26%, 87%, and 90% for P. aeruginosa, M. smegmatis, and C. krusei, respectively. The ethanol extracts caused significant leakage of proteins in these microorganisms. In conclusion, the pods of P. thonningii contain phytochemicals with antimicrobial properties. The pods of the plant can be a source of phytochemicals that can serve as sources of lead compounds with antimicrobial effects. One of the mechanisms of action of these phytochemicals is via membrane-damaging effects on microbes.

Microbial Synthesized Ag/AgCl Nanoparticles Using Staphylococcus pasteuri sp. nov., ZAR1: Antimutagenicity, Antimicrobial Agent

This study investigated the microbial synthesis of Ag/AgCl nanoparticles, their mutagenicity, antimutagenicity and antibacterial effects. For this purpose, bacteria isolates were taken from soil samples of Zarshouran gold mine. One silver resistant bacterial strain was selected for the production of silver nanoparticles. Results of the phylogenetic analysis showed that the strain ZAR1 was 99% similar to Staphylococcus pasteuri. The synthesis of the nanoparticles was confirmed using UV–vis spectroscopy, FTIR, XRD, DLS, and SEM-EDX. The analysis of the nanoparticles synthesized with extracellular extract of bacteria showed that the nanoparticles were spherical with a size of approximately 20–85 nm. Also, the ability of TSB media for the synthesis of silver nanoparticles was evaluated. The formation of Ag/AgCl nanoparticle composites was detected cubic form in the range of 20–50 nm. Antibacterial activity of the nanoparticles was determined against sixty-six pathogenic bacteria. Our results indicated that the nanoparticles had high antimicrobial activity against pathogenic bacteria. Moreover, the nanoparticles stabilized using sodium alginate showed high antimicrobial effects. Ames test revealed that Ag NPs did not display a mutagenic effect. Moreover, the results showed that the nanoparticles were antimutagenic. The percent inhibition of mutagenicity was approximate 97–99%.

Получение наночастиц меди в плазме комбинированного ВЧ+DС разряда

Copper nanoparticles are gaining more and more attention of researchers due to their properties such as high electrical conductivity, well-defined catalytic and antimicrobial effects, etc. The range of their application is extensive – scientific research, medicine, microelectronics and much more. To date, various methods for the synthesis of copper nanoparticles have been developed and successfully applied, in particular chemical, electrochemical, sonochemical, etc. But a significant drawback of such methods is the unsatisfactory purity of the resulting nanomaterial. In this work, a combined high-frequency discharge with an additional constant voltage (HF/DC) was used to obtain Cu particles. A technique for producing nanometer-sized copper particles was developed and studied, and as further analysis using a scanning electron microscope showed, the particles have a spherical shape with diameters ranging from 60 nm to 300 nm.

СРАВНИТЕЛЬНОЕ АНТИМИКРОБНОЕ ДЕЙСТВИЕ ЦЕОЛИТОВ, СОДЕРЖАЩИХ МЕТАЛЛЫ НА STAPHYLOCCOCUS AUREUS, PSEUDOMONAS AERUGINOSA И CANDIDA ALBICANS

Pathogenic bioagents have a great influence on the health of animals and humans. Every year, the number of microorganisms that pose a threat to animal health is growing. Along with this, the large-scale use of antibiotics in agriculture creates problems of antibiotic resistance for pathogenic bioagents. The search for antimicrobials in this regard is a priority. As a result, the search for new antimicrobials, especially antibiotics, has become ubiquitous for animal health. In the world, scientists on this problem have published many works devoted to Staphyloccocus aureus, Pseudomonas aeruginosa, Candida albicans, etc. 200 ml of 0.1 N solutions of heavy metals (AgNO3, CuSO4, Ni(NO3)2, Pb(CH3COO)2, ZnSO4). Here we obtained a modified Ag, Cu, Ni, Pb and Zn zeolite tuff, which we tested on strains of the aforementioned pathogens. To ensure a constant concentration of metals in the experiment, the obtained dried powder was diluted in 10 ml of sterile distilled water and vigorously shaken before being placed on the surface of the medium with the applied pathogen culture. Among all synthetic zeolites tested on these three pathogens, zeolite containing Ag+ and Cu+2 exhibited antagonistic activity. A high antimicrobial effect of Ag zeolite was observed against P. aeruginosa and C. albicans compared to S. aureus. Conversely, copper-containing zeolite showed a higher antimicrobial effect against S. aureus with less effect on P. aeruginosa and almost no effect on C. albicans. Surprisingly, Ni-, Pb- and Zn-zeolites did not have any antagonistic effect on all tested pathogens. The control zeolite also had no effect on pathogens.

Effect of Physical and Chemical Treatments on Viability, Sub-Lethal Injury, and Release of Cellular Components from Bacillus clausii and Bacillus coagulans Spores and Cells.

Bacterial spores are of concern to the food industry due to their ability to survive processing and their potential to subsequently germinate and grow in food. In this paper, two strains belonging to the genus Bacillus (B. clausii DSM 8716 and B. coagulans DSM 1) were studied under in vitro conditions after the application of essential oils, and physical treatments; cells and spores’ susceptibility, the extent of sub-lethal injury and the release of cellular components as a function of treatment and targets (cells, spores, old or activated spores) were studied. The highest antimicrobial effect was found for cells treated through citrus extract, while both essential oils and physical treatments could cause a sub-lethal injury on the surviving cells and spores; in addition, the spores of B. coagulans released dipicolinic acid (DPA) and proteins. Sub-lethal injury should be considered when designing a food processing treatment, because injured microorganisms could either repair the damage or be inactivated with a different effect on microbial stability of foods.

Study the Effect of Aqueous Extract of Garlic (Allium sativum) on Healing Procedure of Burn Wound on Rat

High antimicrobial and antioxidant effects of garlic make it possible to use as an effective topical cream to heal burn wound injuries. The present research was done to evaluate the burn wound healing effects of the aqueous extract of garlic on rat model. Aqueous extract was achieved from fresh garlic. Thirty healthy adult rats were subjected to burn wounding and then randomly treated with silver sulfadiazine (positive control), cream base (negative control) and garlic topical cream (0.8%, 0.4% and 0.2%). Rats were then maintained for 21 days and macroscopic and microscopic examinations were performed through the experiment. Burn wound contraction was increased in all groups of rats during the experiment period. The highest percent of burn wound contraction at day 21 was found in rats treated with 0.4% garlic topical cream (88.10%), while those treated with cream base had the lowest wound contraction (70.30%). Rats treated with 0.4% garlic topical cream showed more rapid granulation, formation of scar and healingin the macroscopic examination. Additionally, rats treated with 0.4% garlic topical cream had the higher amounts of tissue granulation with dense collagen deposition in the microscopic examination after 21 days of wounding. Burn wound healing effects of the garlic extract was not dose depended. It seems that application of 4% garlic cream is an effective way to improve the burn wound healing of rats. However, supplementary studies are needed to evaluate other effects of garlic cream on burn wound.

Antibacterial activity of essential oils encapsulated in chitosan nanoparticles

Abstract In this study, cinnamon (Cinnamomum zeylanicum), thyme (Thymus vulgaris) and Schinus molle essential oils (at 125, 250 and 500 µg/mL) were encapsulated in chitosan nanoparticles by ionotropic gelation. Their antimicrobial activity against Staphylococcus aureus ATCC 25923, Enterococcus sp., Escherichia coli ATCC 25922, Klebsiella pneumoniae (BLEE +) and Pseudomona aeruginosa carbapenemase producer was evaluated. The obtained nanoparticles exhibited a regular distribution and spherical shape with size range of 19.7 to 361 nm as observed by using a laser light scattering equipment. It was found that the studied chitosan nanoparticles with essential oils showed high antimicrobial effect than the chitosan and essential oils alone. Enterococcus sp. was the most sensitive bacteria and S. aureus the most resistant. Chitosan nanoparticles and chitosan nanoparticles with cinnamon and thyme essential oils were capable to inhibit growth of Enterococcus sp. and K. pneumoniae. This study demonstrated that chitosan nanoparticles with essential oils were effective against some foodborne pathogens.

The antimicrobial properties and biogenic amine production of lactic acid bacteria isolated from various fermented food products

Lactic acid bacteria (LAB) have been isolated from fermented foodstuff and pre-identified using API 50 CHL and confirmed by polymerase chain reaction method to investigate the protective properties against important foodborne pathogens of their cell-free supernatants (CFS) and neutralized cell-free supernatants (NCFS). The antimicrobial activity of CFS and NCFS was determined using agar well diffusion assay. Biogenic amine production of LAB strains were also monitored in tyrosine decarboxylase broth (TDB). The highest and lowest histamine production were obtained by Pediococcus pentosaceus (155.66 mg/L) and Lactobacillus plantarum (5.96 mg/L), respectively. CFS obtained from LAB isolates showed better antimicrobial effects against pathogens than NCFS. The CFS and NCFS obtained from L. plantarum showed a high antimicrobial effect against S. Paratyphi A with inhibition zone diameter 22.5 and 16.5 mm, respectively. The CFS and NCFS of L. raffinolactis showed strong antibacterial activities against Listeria monocytogenes, with zone diameter 23.5 and 24.5 mm. Practical applications Antimicrobial activity of cell-free and neutralized cell-free supernatants obtained from LAB strains was evaluated. Biogenic amine production of LAB strains were also monitored in tyrosine decarboxylase broth. All LAB isolates had the capacity to produce biogenic amines. Cell-free supernatants obtained from LAB isolates showed better antimicrobial effect against pathogens than neutralized cell-free supernatants. Our results showed that cell-free supernatants can be used as a bio-protective agent in the food industry.

Active packaging for Salmon stored at refrigerator with Polypropylene nanocomposites containing 4A zeolite, ZnO nanoparticles, and green tea extract.

In this study, three types of Polypropylene‐based (PP) films (two active nanocomposites and one control film) containing zinc oxide nanoparticles (ZnO NPs), 4A zeolite (4A Z), and green tea extract (GTE) were studied as modern active packaging's that can adjust the release of antimicrobial agents. The influence of PP nanocomposite with 3% (w/w) ZnO NPs/4A Z/GTE (treatment 1) and 6% (w/w) ZnO NPs/4A Z/GTE (treatment 2) on controlling microbial growth and preserving the sensory and chemical qualities of Salmon over nine days of storage at 4 ± 1°C was evaluated. The disk diffusion test revealed inhibition zones in the range of 10.98 ± 0.03 to 13.42 ± 0.01 m for treatments 1 and 2, respectively; the nanocomposite film with 6% ZnO NPs/4A Z/GTE had the highest antimicrobial effect against Gram‐negative bacteria (p < .05). Chemical analysis revealed that the initial peroxide value of Salmon was 0.68 ± 0.0 mEq/kg, which increased by day 9 to 12.3 ± 0.03 mEq/kg in the control sample, but rising only to 9.9 ± 0.01 and 7.3 ± 0.02 mEq/kg in treatments 1 and 2, respectively (p < .05). The shelf life of Salmon given treatment 2 increased significantly to nine days relative to the control. Accordingly, these nanocomposite films are promising as new active packaging for preventing microbial growth and preserving the quality of salmon.

Preparation and antimicrobial effect of a cinnamaldehyde-based sustained release fumigant tablet for grain storage

Currently, aluminum phosphide tablets have been extensively used as fumigant for grain storage because they could release phosphine that shows highly efficient anti-microorganism. However, phosphine is highly toxic and flammable which usually causes production accidents. Therefore, this study aimed to develop a novel fumigant based on cinnamaldehyde and study its antimicrobial efficacy for grain storage. The novel fumigant tablet was composed of cinnamaldehyde, silica, citric acid and sodium bicarbonate. Results showed that mesoporous silica with ultra-high specific surface area (1036.5 m2/g) served as carrier for cinnamaldehyde. The mixture of citric acid and sodium bicarbonate reacted with moisture to generate carbon dioxide which was helpful to release cinnamaldehyde. As expected, the fumigant tablet displayed a sustained release effect. The in vitro culture experiments showed that cinnamaldehyde had high antimicrobial effect against five fungi including Aspergillus flavus, Aspergillus candidus, Aspergillus niger, Fusarium and Penicillium. In the accelerated mildew simulation experiment (temperature: 35 °C, humidity: 98%), the blank group without mildew preventive began to go mouldy after five days, the control group with only cinnamaldehyde became mildew one week later, whereas there was no visible mildew growth in the experimental group with the fumigant tablet after one week. The number of fungal colonies in the blank group and the control group after one week was 8.3 × 104 and 6.5 × 103 CFU/g, respectively, while there were no fungi detected in the experimental group. This cinnamaldehyde-based fumigant tablet is a green and safe mildew preventive, which provides an alternative solution to aluminum phosphide tablet for grain storage.

Antilisterial Activity by Enterococcus Species Isolated from Traditional Cheeses

In this study, it was aimed to detect the antimicrobial activity of 312 Enterococcus species against Listeria monocytogenes. Antimicrobial activity was detected by agar spot and well diffusion assay. A total of 201 enterococcal strains inhibited the growth of L. monocytogenes strains based on the agar spot test. Only 44 strains showed antimicrobial activity against L. monocytogenes strains using agar well diffusion assay. Of the 44 enterococcal strains screened, 6 E. faecium (2.99%) strains had a high antimicrobial effect against indicator L. monocytogenes strains. The antilisterial activity of 6 E. faecium strains had lost after treatment of proteinase K, trypsin and pepsin. The antimicrobial compounds of these strains could be a protein or peptides nature. E. faecium strains were more active against L. monocytogenes than E. faecalis strains.

Antimicrobial activity and therapeutic efficacy of thiacycline in subclinical mastitisin sheep

Relevance. The work is devoted to the results of studying of the antimicrobial and therapeutic efficacy of the drug thiacycline in subclinical mastitis in sheep. The aim of our research еsеwas to study the antimicrobial activity and therapeutic efficacy of thiacycline in subclinical mastitis in lactating ewes.Methods. The study of antimicrobial activity was carried out by the method of serial dilutions in a liquid nutrient medium, on the basis of the Caspian zonal NIVI in the laboratory on the study of diseases of non-infectious etiology of farm animals. The therapeutic efficacy of thiacycline was studied in the SEC "Bukhti" of the Gunib district of Dagestan Republic on ewes of the Dagestan rock, aged from 3 to 5 years, with subclinical mastitis, in the amount of 51 heads. Animals on the basis of analogues were divided into two groups: experience (n = 26), control (n = 25). The animals of the experimental group were treated with thiacycline, the drug was administered intramuscularly, once a day, in dose 0.1 ml/kg. The test combination drug thiacycline developed by VIC. The control group was treated with bicillin-3, in dose 600,000 units per head, with an interval 72 hours.Results. The complex antibacterial drug thiacycline has a wide spectrum and high antimicrobial effect against museum strains and potential causative agents of sheep mastitis. The therapeutic efficacy of thiacycline in the treatment of subclinical mastitis in sheep – 97.0%, which is on 13.0% higher compared to bicillin-3. On the 7th day after the last administratin of preparation all the physicochemical parameters of milk corresponded to the physiological norm.

Preparation of hyaluronic acid and copolymeric hyaluronic acid: sucrose particles as tunable antibiotic carriers

Hyaluronic acid (HA) and copolymeric HA:Sucrose (HA:Suc) particles were synthesis with two different crosslinkers (Xs), divinyl sulfone (DVS) and glycerol diglycidyl ether (GDE) in 0.5–20 μm size range. The sustenance potential of HA:Suc particles in bacterial growth media was examined with time, up to 72 h incubation time in the cultivation of various gram-negative (GN) and gram-positive (GP) bacterial strains. Furthermore, ciprofloxacin, model drug was loaded into HA and HA:Suc particles few times by chemical conjugations; e.g., 1st and 2nd chemical conjugations and named as 1C and 2C, respectively. To increase the drug loading amount into HA-based particles, 2C particles was placed in drug solution for physical adsorption (2C + A). Therefore, drug carrier capacity of HA-based particles was enhanced almost 6.5-fold with the highest ciprofloxacin release from HA particles was 43.47 ± 2.36 mg/g within 120 h. The antimicrobial susceptibility studies revealed that ciprofloxacin-loaded copolymeric HA:Suc particles with 2C + A loading process has the highest antimicrobial effects. The minimum inhibition concentration (MIC) against E. coli, P. aeruginosa, S. aureus, and B. subtilis strains were found to range between 0.25–1 mg/mL, and an increasing inhibition trend was observed by increasing the incubation time up to 72 h due to linear drug release profile from HA particles.

Polyvinyl alcohol/thymol film for food packaging application: preparation, characterization and in vitro evaluation

Evolution of new materials that offer protection for active food ingredients is the focal point for food application research. Release of antimicrobial compounds from the packaging film is one of the common methods. In this research, an antimicrobial active packaging film based on poly(vinyl alcohol) (PVA) and thymol was prepared via freezing/thawing technique. The effect of thymol content on the property and structure of the film was characterized by Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), swelling and gel fraction measurements. Furthermore, the antimicrobial test shows that the prepared film has high antimicrobial effect against Gram-positive bacterial strains (Bacillus subtilis), fungal strain (Candida albicans), and Gram-negative bacterial strains (Salmonella senftenberg and Escherichia coli) in comparison with the control PVA film. The current approach verified that PVA film containing thymol could be applied as an alternative for food backing applications

Antimicrobial Effect of Photodynamic Therapy Using Plaque Disclosing Agent

The aim of this study was to evaluate the antimicrobial effect of photodynamic therapy (PDT) using plaque disclosing agent, 10 - 20 mM erythrosine, as a photosensitizer.&lt;br/&gt;Multispecies cariogenic biofilms containing Streptococcus mutans , Lactobacillus casei and Candida albicans were formed on hydroxyapatite disc. 20 μM, 10 mM and 20 mM erythrosine were applied as a photosensitizer for 3 minutes, and then light-emitting diode (LED) irradiated for 24 seconds. Colony-forming unit (CFU) were measured and biofilms were observed using confocal laser scanning microscopy (CLSM). CFU were significantly decreased in the PDT groups using 10 - 20 mM erythrosine (10 mM, 20mM) and the results were also confirmed by CLSM.&lt;br/&gt;This study confirms the high antimicrobial effect of photodynamic therapy using plaque disclosing agent as a photosensitizer.

Investigation of the sensitivity of pathogens of purulent-inflammatory processes of the mediastinum to modern antiseptics

Annotation. A well-chosen tactic for the prevention and treatment of infectious complications in patients with purulent-inflammatory processes of the mediastinum is important in reducing the colonization of the biotope by pathogens, contributes to the reduction of inflammation and accelerates recovery. The aim of our work was to conduct a comparative study of the antimicrobial efficacy of antiseptic drugs (decasan, myramistinum, chlorhexidine, povidone iodine and polyhexamethylene guanidine) on 278 clinical strains of microorganisms (S. aureus, E. coli, K. pneumoniae, Enterobacter spp.), which cause purulent-inflammatory complications of the mediastinum in patients. For the comparative characterization of the antimicrobial action, the method of double dilutions was used; calculated antiseptic activity index (AAI); a quantitative suspension test was performed to evaluate the decontamination effect of antiseptics. Standard methods of descriptive statistics and special and office programs “STATISTICA 6.0”, “Microsoft Excel 2010” were used. Staphylococci showed the highest level of sensitivity to most of the antiseptics under study. The mean MBSC values of S. aureus clinical strains for decasan, myramistinum, chlorhexidine was respectively 1.75±1.27 µg/ml, 3.25±2.27 µg/ml, and 5.53±3.74 µg/ml. The AAI of myramistinum and chlorhexidine before the Pseudomonas was 4.5, which is the threshold for clinical activity. The clinical activity of a solution of povidone iodine against infections caused by P. aeruginosa is doubtful, based on the activity level of 2.6. The studied antiseptics provided a full decontamination effect against most strains at 5 min exposure, the decontamination effect lasted for 15 min, followed by 30 min. There were found single microorganisms, the number of which gradually increased and after 1 hour reached 1.9×104 and 1.5×102 CFU/ml, respectively. The high sensitivity of gram-positive and gram-negative pathogens to decasan and polyhexamethylene guanidine hydrochloride substantiates their high antimicrobial effectiveness and opens wide prospects for their use in the prevention and treatment of infectious complications in modern conditions.

Antimicrobial activity of copper‐humate‐cellulose sheets

During our research, cellulose‐based test sheets containing copper and potassium humate were prepared and tested against several bacterial and fungal strains. The energy dispersive X‐ray spectrometry and attenuated total reflectance (ATR) Fourier‐transform infrared spectroscopy revealed that humate contributed to increase the copper content of the test sheets. The antimicrobial impact of test sheets on various fungi (Penicillium expansum, Wallemia sebi, and Aspergillus brasiliensis) and bacteria (genera Micrococcus, Enterococcus, Bacillus, Salmonella, Staphylococcus, Listeria genera) was tested using a modified agar diffusion‐based assay. On the basis of the disc diffusion results, the sheets effectively inhibited all the tested fungi and Gram‐positive bacteria. The highest antimicrobial effect was exhibited by the copper‐containing test sheet with 1:0.1 and 1:0.25 cellulose:humate weight ratio. Deterioration test with blackberries demonstrated the shelf life extending effect of the sheets.

Phenolic constituents, antioxidant and antimicrobial activities of methanolic extracts of some female cones of gymnosperm plant

In the present study, the total antioxidant activity, the total phenolic content, and the antimicrobial activity of methanol extracts obtained from the female cones of Pinus brutia, Pinus nigra, Cupressus sempervirens L., Thuja orientalis L., and Cedrus libani were evaluated. The in vitro total phenolic content, the antioxidant, and the antimicrobial activities were determined using the Folin-Ciocalteu reaction, the DPPH radical scavenging assay and the disc diffusion method, respectively. The results of the present study showed that the extracts of the female cones prepared in methanol had the antimicrobial activity against the test microorganisms and the highest antimicrobial effect was observed against Staphylococcus epidermidis, Staphylococcus aureus, and Bacillus subtilis. The total phenolic constituents of the extracts were determined to be in the ranges from 69 to 220 mg GA/100 g. All extracts exhibited antioxidant activity with concentrations necessary to inhibit the activity of DPPH radical by 50% (IC50) ranging from 0.35 to 17.21 µg/mL. The results indicate that the extracts of the cones exhibit acceptable antioxidant and antimicrobial activities and suggest that these cones’ extracts may serve as a potential source of natural antioxidants and antimicrobials for food or medical purposes.