Agar Diffusion Method Research Articles

Antibacterial activity of silver nanoparticles synthesized from Citrus aurantium and its synergistic effect of the combination of silver nanoparticles with ampicillin against Proteus mirabilis

Abstract Background: Proteus mirabilis is one of the most infectious organisms that cause a various infections involving those of the skin, wounds, and urinary tract. This study describes the synthesis of silver nanoparticles (AgNps) and using it as an antibacterial agent. Objective: To determine the activity of AgNps and synergistic effect of combination of AgNps with ampicillin (AMP). Materials and Methods: Out of 205 samples, 32 isolated were identified as P. mirabilis and determine the inhibition zone by using AgNps and its combination with AMP. The AgNps were biosynthesized by Citrus aurantium and then characterized using Ultraviolet (UV)-visible spectroscopy, X-ray diffraction (XRD) and transmission electron microscope (TEM). The antibacterial activity of AgNps was done using well diffusion agar method and the activity was evaluated by calculating the increase in the inhibition zone and reduction in the bacterial growth. Results: The synthesized AgNps was first characterized by UV-visible spectroscopy which showed a peak between 400 and 500 cm–1. The color changes from clear yellow to red or brown color indicate the formation of AgNps. The particle size of AgNps was calculated and found to be 21.24 nm by XRD. The TEM images showed the presence of very regular particles in shape of nanospheres with a particle size in the range of 10–28 nm. Different concentrations (25, 50, 75, 100 µg/mL) were used for determining the activities of AgNps and the combination of AgNps with AMP, and the result showed that the most efficient in inhibition zone was at concentration 100 µg/mL. Conclusion: This study concluded that the green synthesized AgNps from C. aurantium leaves extract have most potential as antibacterial against P. mirabilis.

Preliminarily investigation on the In-vitro Antimicrobial, Antioxidant and Antidiabetic Activities of Sorindeia warneckei Extracts

Abstract Phytochemicals that are naturally occurring in plants are known to be potentially bioactive, having anti-oxidative, antimicrobial and enzyme inhibiting potentials. This study investigated the antimicrobial, antioxidant and antidiabetic activities of the methanol and dichloromethane extracts of the leaf and stem Sorindeia warneckei. The plant extract showed the presence of saponins, flavonoids, terpenoids, tannins, glycosides, coumarins, steroids, alkaloids, anthraquinones and reducing sugars. The antioxidant potential was evaluated using DPPH radical scavenging assay while the antidiabetic activity was evaluated using an in-vitro α-amylase inhibitory assay. The DPPH free radical scavenging activity was expressed in % inhibition with L Ascorbic acid as standard showing IC50 0.69μg/ml with methanol extract while dichloromethane leaf extract having the highest activity at 0.45μg/ml. The α-amylase assay showed that the extracts exhibited potent alpha amylase inhibitory activity in a dose dependent manner with the leaf methanol extract having an IC50 of 2.33µg/L. The antimicrobial screening using the agar diffusion and agar dilution methods against the bacteria isolates Staphylococcus aureus, Salmonella typhirimurium, Escherichia coli and Streptococcus mutans and the fungal isolates Candida albicans, Aspergillus niger, Aspergillus flavus and Rhizopus oligosporus showed a good positive result. Preliminary investigation reveals that Sorindeia warneckei, contain bioactive compounds that possess promising pharmaceutical potentials that could be exploited.

Physicochemical Constituent, Phytochemical Analysis and Antimicrobial Activity in Ethanolic Extract of Cyanotis Axillaris

Cyanotis axillaris belong to family Commellianaceae. The present investigation deal with the physicochemical constituent, phytochemical analysis and antimicrobial activity in ethanolic extract of whole plant of Cynotis axillaris. The plant part decoction used in Ayurveda to cure many diseases [2]. The evaluation of physicochemical constituents was carried out by ash value, extractive value and phytochemical constituent in plant. The antibacterial activity was tested by cup plate agar diffusion method. The antibacterial activity carried out against E. coli, Staphylococcus Aureus, Bacilis subtilis and Proteus species

Antibacterial Activities of Heterotrigona itama Honey Farmed in Ex-Mining Area

Honey is considered to be a valuable non-timber forest product due to its numerous preventative and therapeutic properties. The nutritional content in honey is the most complete so it can boost the immune system. This study aims to determine the potential inhibition of Heterotrigona itama stingless bee honey against the activity of Staphylococcus sp bacteria and Propionibacterium sp bacteria. This research adopted the agar diffusion method to conduct antibacterial testing. The nutrient agar media was aseptically put into a sterile petri dish and thereafter left to air-dry. Following this, the bacterial suspension was reconstituted and subsequently inoculated onto the solidified agar surface by creating perforations. The experiment involved conducting antibacterial tests using many concentrations of the samples. The experimental setup included a positive control using chloramphenicol and a negative control using distilled water. The test results showed that the activity of the inhibition of Heterotrigona itama kelulut honey against Staphylococcus sp bacteria and Propionibacterium sp bacteria belonged to the strong antibacterial category. The antibacterial activity of honey exhibits an enhanced potency against both types of bacteria in direct proportion to the content of the honey sample.

Assessment of the antibacterial activity of lemongrass-extracted essential oil

Lemongrass is one of the medicinal plants having significant applications to cure various diseases. This study aims at extracting essential oils from lemongrass plants and examining their antibacterial activity. The sample of lemongrass for this study was collected from Kailali District, Nepal. The leaves of lemongrass were collected, washed, cut into small pieces, and dried in the sun. Then pieces of lemongrass were steam distilled for about 4 hours using the Clevenger apparatus, and oil was extracted. The extracted essential oil was further utilized to study its antibacterial activity in human pathogens, namely Staphylococcus aureus (S. aureus: gram-positive bacteria), by Agar diffusion and broth dilution methods. It was found that the zone of inhibition for S. aureus in concentrations of 100%, 75%, 50%, and 25% was about 25 mm, 11 mm, 9 mm, and 0 mm, respectively. In addition, it is clear from this study that the gram-positive bacteria were sensitive to essential oils. The lowest and highest zones of inhibition were shown against S. aureus at 25% and 100% concentrations, respectively. The zone of inhibition at 100% concentration is 25 mm and at 25% concentration is 0 mm, so lemongrass oil is effective against drug-resistant organisms only at high concentrations.

Chemical constituents from Cordia myxa L. (Boraginaceae) and their antibacterial activity

Chemical investigation of Cordia myxa L. (Boraginaceae) resulted in the isolation of the following ten known compounds: 1-naphthaleneacetic-5-carboxy-1,2,3,4,4a,7,8,8a-octahydro-1,2,4a-trimethyl-[1S-(1α,2β, 4a,8aα)]-acid (1), hexacosanoate-1-glyceryl (2), 3β-urs-12,20(30)-diene-27,28-dioic acid (3), 3β-D-glucopyranosylurs-12,20(30)-diene-27,28-dioic acid (4), stigmasterol (5), stigmasterol-3-O-β-D-glucopyranoside (6), oleanolic-acid (7), 3-O-acetyl-oleanolic acid (8), betulin (9) and spinasterol-3β-O-D-glucopyranoside (10). The isolated compounds were characterised by using spectroscopic methods, 1D and 2D NMR, mass spectroscopy (ESI-MS) and by comparison with the literature data. To the best of our knowledge, compounds 1, 3, 4, 8 and 10 were isolated for the first time from the Cordia genus. This result improves the chemotaxonomy knowledge of the Cordia genus. The antibacterial activities were performed by the Muller–Hinton agar diffusion method. The antibacterial activities were studied on Salmonella typhi, Staphylococcus aureus, Vibrio cholerae, Pseudomonas aeruginosa and Escherichia coli ATCC 25922. Compounds 8 and 9, at 20.0 mg/mL resulted to be effective antimicrobial against E. coli, V. cholerae and P. aeruginosa.

FORMULATION AND ACTIVITY TESTING OF RED ALGAE (Eucheuma cottonii) EXTRACT GEL AGAINST THE BACTERIA Propionibacterium acnes

Flavanoids are one of the many compounds in phenols that have the ability to denature bacterial cell membrane proteins, thus inhibiting cell growth. The purpose of this study was to formulate an anti-acne gel for the ethanolic extract of red algae (Eucheuma cottonii) and to test its antimicrobial activity against Propionibactericum acnes. The method used is laboratory research design by making antiacne gel preparations of red algae extract with concentrations of 1%, 3%, 5% and testing the antimicrobial activity with the agar diffusion method using wells on MHA media which is incubated for 1x24 hours. The results of the evaluation of the gel preparation before and after the cycling test met the requirements of organoleptic, homogeneity, pH, viscosity, and dispersibility where each formula was stable in the gel preparation. The results showed that red algae extract (Eucheuma cottonii) could be formulated and was stable in the form of an anti-acne gel and had antibacterial activity. In formula I with a concentration of 1% the inhibition zone formed was 36.33 mm, in formula II with a concentration of 3% the inhibition zone formed was 38.79 mm and in formula III with a concentration of 5% the inhibition zone formed was 34.27 mm. So that which has optimal antibacterial activity against Propionibacterium acnes is formula II with a concentration of 3% and an area of ​​inhibition zone of 38.79 mm

Contamination of a Water Stream and Water Drainage Reaching Matosinhos Beach by Antibiotic-Resistant Bacteria.

Antibiotic-resistant bacteria represent a major public health concern, especially impacting medical care centers and hospitals, thereby challenging the effectiveness of current infection treatment protocols. The emergence and persistence of antimicrobial resistance in the environment have been thoroughly researched, with a focus on the aquatic environment as a potential reservoir of these bacteria in areas with anthropogenic contamination. Having this in mind, this work aims to investigate the water streams of Riguinha and Brito Capelo Street, both of which ultimately flow into Matosinhos Beach in Portugal, to determine the potential presence of fecal contamination. Six water samples were collected and analyzed within twenty-four hours from these two water streams. A phenotypic characterization was performed in various volumes on MacConkey agar with antibiotics. Randomly selected lactose-fermenting gram-negative bacteria underwent antimicrobial susceptibility tests using the agar diffusion method following EUCAST guidelines, covering β-lactam and non-β-lactam antibiotics. The isolates were analyzed through Polymerase Chain Reaction. The findings of this study confirm that both water streams were contaminated by multidrug-resistant bacteria such as Enterobacteriaceae, including Escherichia coli, the KESC group, and Pseudomonas, exhibiting extended-spectrum β-lactamases (ESBL), AmpC β-lactamases, and carbapenemases. These indicate the presence of fecal contamination with relevant antimicrobial-resistant threats.

Synergistic and antagonistic medicinal activities of essential oil of Monodora myristica

Synergetic and antagonistic medicinal activities of crude and fractionated essential oil from the seed of Monodora myristica were investigated. The crude essential oil was extracted by steam distillation and then subjected to column chromatography; three fractions (N1, N2, and N3) were obtained. To identify the components, gas chromatography and mass spectrometry (GC-MS) investigation was utilized. The phytochemical parameters were determined by standard analytical methods. 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) were used to evaluate the antioxidative capacity. and, the anti-diabetic activity was performed using α-amylase and α-glucosidase assay. The Agar diffusion method was used to determine the antibacterial activities. The GC-MS analysis indicated p-cymene (21.12%) as the major component of the crude essential oil. The antioxidant activity using DPPH varied from 614 to 704 µg/mL, while the ABTS activity ranged between 281-342 µg/mL. The α-amylase assay showed fraction N1 with IC50 value of 3.21 µg/mL, while for α-glucosidase assay, fraction N2 with IC50 2.15 µg/mL recorded the least value. The minimum inhibitory concentration values for the crude extract and all the fractions against the strains of bacteria ranged from 6 to 12.5 mg/mL Both crude extract and fractionated essential oil showed antioxidant, anti-diabetic and antibacterial activities.

Synergistic effects of CuO/TiO2 -chitosan-farnesol nanocomposites: Synthesis, characterization, antimicrobial, and anticancer activities on melanoma cells SK-MEL-3.

The current investigation focuses on synthesizing copper oxide (CuO)-titanium oxide (TiO2 )-chitosan-farnesol nanocomposites with potential antibacterial, antifungal, and anticancer properties against Melanoma cells (melanoma cells [SK-MEL-3]). The nanocomposites were synthesized using the standard acetic acid method and subsequently characterized using an X-ray diffractometer, scanning electron microscope, transmission electron microscopy, and Fourier transform infrared spectroscopy. The results from the antibacterial tests against Streptococcus pneumoniae and Stapylococcus aureus demonstrated significant antibacterial efficacy. Additionally, the antifungal studies using Candida albicans through the agar diffusion method displayed a considerable antifungal effect. For evaluating the anticancer activity, various assays such as MTT assay, acridine orange/ethidium bromide dual staining assay, reactive oxygen species (ROS) generation assay, and mitochondrial membrane potential (MMP) analysis were conducted on SK-MEL-3 cells. The nanocomposites exhibited the ability to induce ROS generation, decrease MMP levels, and trigger apoptosis in SK-MEL-3 cells. Collectively, the findings demonstrated a distinct pattern for the synthesized bimetallic nanocomposites. Furthermore, these nanocomposites also displayed significant (p < 0.05) antibacterial, antifungal, and anticancer effects when tested on the SK-MEL-3 cell line.

Microbial inhibition test and optimization of temperature, aeration fermentation of endophytic Fusarium sp LBKURCC 41 from Dahlia tuber (Dahlia variabilis)

Link of Video Abstract: https://youtu.be/G8AKREK9E9Q Introduction: Synthetic drugs can cause toxicity. Finding new natural sources of medicinal materials with low toxicity is one of the efforts to reduce it. This was done by using biotechnology from endophytic fungi growing on dahlia tubers (Dahlia variabilis). This study aimed to find the optimum temperature and aeration in the fermentation of endophytic fungi Fusarium sp LBKURCC 41 in producing secondary metabolites. Methods: The method of this research was temperature optimization with temperature variations of 10˚C, 27˚C, 37˚C and 40˚C. For aeration, the variation of oxygen provided was 50 ppb and 100 ppb. Both fermentation environment factors were incubated for 5, 10, 15, 20, and 25 days. The activity test was conducted against pathogenic microbes E. Coli, S. aureus, and C. albicans using the agar diffusion method. Positive controls used ketoconazole for Candida albicans and ciprofloxacin for E. coli and Streptococcus aureus bacteria. Result: The results showed the optimum temperature of the fermentation of endophytic fungi Fusarium sp LBKURCC 41 based on statistical analysis of T-Test for (p &lt; 0.05) is to have the highest inhibition zone diameter value of 10.5 ± 0.62 mm on day 20 against Candida albicans with a positive control of 6.0 ± 0.23 mm. For aeration, the highest inhibition zone value was 12.3 ± 0.12 mm with a positive control of 19.5 ± 0.12 mm. Conclusion: The optimum temperature of the fermentation is to have the highest inhibition zone diameter value of 10.5 ± 0.62 mm. The ability of endophytic fungi to produce secondary metabolite compounds is determined by the temperature and aeration used.

Uji aktivitas antimikroba ekstrak daun tumbuhan akar kucing (Acalypha indica L.) terhadap mikroba patogen manusia

The leaves of Acalypha indica L. were used as the object that are easily found around the home contain secondary metabolites as antimicrobials for Meticillin Resistant Staphylococcus aureus (MRSA) and Candida albicans. The method used for plant sampling is purposive sampling method. Extraction of active compounds using maceration method. The antimicrobial potency test used the agar-diffusion method using two types of microbial pathogens: Meticillin Resistant Staphylococcus aureus (MRSA) and C. albicans. Each paper disk was given 50 L of bacterial isolate and incubated at 370C for 24 hours and continued for 48 hours. The parameter observed is the clear zone formed around the paper disk. The results showed that the leaves of contained compounds that could inhibit the growth of MRSA bacteria and the fungus. A good solvent to extract the active compounds contained in the leaves of is distilled water. The extract - distilled water treatment with a concentration of 100% had the widest inhibition zone among other treatments, which was 4.5 mm against the growth of the fungus

Anti-microbial and anti-cancer efficacy of acetone extract of Rosa chinensis against resistant strain and lung cancer cell line

BackgroundScreening of herbal plants for various therapeutic properties is the hour as it shows promising activity. Scientific evidence of the pharmacological activity of the plant strengthens the traditional application of plants.MethodsRose flowers (Rosa chinensis) were procured and grounded into a coarse powder. The DNA was isolated from rose flower and molecular identification was performed by rbcL-BF and rbcL-724R primers. Antibacterial activity was evaluated by using disc and agar diffusion methods and the anti-cancer effect of the rose flower extract (RE) was examined using MTT assay in lung cancer cell line. The mechanism of cell death induced by RE was qualitatively measured using Acridine orange/Ethidium bromide staining and Hoechst staining. GC-MS analysis was performed using GC-MS-5975C.ResultThe RE showed potent antimicrobial activity against various ATCC cultures. The rose extract strongly inhibits the growth of ESBL resistant organism along with inhibition of biofilm formation in the ESBL resistant organism. The extract caused apoptotic and necrotic cell death in lung cancer cells. GC-MS analysis demonstrated the presence of several biologically active compounds such as Clindamycin, Phytol, Octanoic acid, and Stigmasterol which might be the reason for the therapeutic properties of the plant.ConclusionThis study shows the antimicrobial and biofilm inhibition activity against the clinical isolates of Klebsiella pneumonia. The study shows the cytotoxic and apoptotic activity in A549 cancer cell line. Thus, the plant may act as a potent antimicrobial drug against resistant strains.

Development of multifunctional bioactive food packaging based on silver nanoparticles/grape fruit peel extract reinforced PVA composites

Active food packaging based on bio-wastes has gained considerable attention these days due to their ecofriendly and biodegradable behavior. In this study, multifunctional bio-composite films with remarkable anti-oxidant and anti-microbial attributes were synthesized by incorporating biosynthesized silver nanoparticles (AgNPs) and grape fruit peel extract (GFPE) into polyvinyl alcohol (PVA) matrix. Synthesized films were characterized in terms of Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Differential scanning calorimetry (DSC) and Dynamic Mechanical Analyzer (DMA). Antioxidant activity of AgNPs-GFPE/PVA films was determined by %DPPH scavenging ability and Ferric reducing antioxidant power assay while antimicrobial activity was measured by agar diffusion method. XRD analysis revealed the semi-crystalline behavior of synthesized composites with characteristics peak at 38° whereas SEM micrographs confirmed the homogeneous dispersion of reinforcement and porous rough surface structure of AgNPs-GFPE/PVA nano-composites. AgNPs-GFPE/PVA nanocomposite exhibited glass transition temperature (Tg) at ∼116 °C and Tm ∼191 °C along with the storage modulus of 685 MPa, revealing significantly enhanced thermal and mechanical stability of composites compared to pure PVA films. The composite films exhibited remarkable antioxidant potential i.e DPPH scavenging activity ∼50 % and reducing power ∼ 0.58. The AgNPs-GFPE/PVA nano-composite films exhibited remarkable antimicrobial activity in response to food borne pathogens. The results designated that the synthesized composite films have prodigious potential of being cheap, eco-friendlier substitute to conventional materials for application in food packaging, which certify the safety and economical life span of packed food.

The Effect of Plasma-Activated Water Combined with Rosemary Extract (Rosmarinus officinalis L.) on the Physicochemical Properties of Frankfurter Sausage during Storage.

This study investigated the impact of plasma-activated water (PAW) and rosemary extract on the bacterial inactivation and quality attributes of Frankfurter sausages during a 6-day storage period. The antibacterial activity, total phenol content (TPC), and total flavonoid content (TFC) of the rosemary extract were evaluated. The TPC of the rosemary extract was 89.45 mg gallic acid/g dry weight, while the TFC was 102.3 mg QE/g dry weight. Even at low concentrations, the rosemary extract effectively inhibited the growth of all the tested pathogens using the Well Diffusion Agar method (WDA). The sausages were treated with different concentrations of PAW and rosemary extract and stored for 1 and 6 days. Sample B (100% rosemary extract + PAW treatment) showed the greatest reduction in microbial load and was selected for further analysis. Throughout the storage period, Sample B exhibited no significant changes in pH, moisture content, textural parameters, or sensory evaluation compared to the control group. However, the hardness and color parameters (L*, a*) of Sample B decreased, while the TBARS value increased after 6 days of storage. The combination of PAW and rosemary extract, particularly Sample B, effectively inhibited bacterial growth in the Frankfurter sausages without compromising most quality attributes. Some changes in hardness, color, and lipid oxidation were observed over the extended storage period.

Perbandingan ekstraksi akar kucing (Acalypha indica l.) dengan ekstrak etanol 96% dan ekstrak akuades terhadap pertumbuhan EPEC dan Candida albicans

The root of the cat (Acalypha indica L.) was used as the object of research and extraction was carried out to determine the antimicrobial activity of 96% ethanol extract and distilled water against EPEC (Enterophatogenic Escherichia coli) bacteria and the fungus Candida albicans. The method used for plant sampling is purposive sampling method. Extraction of active compounds using maceration method. The antimicrobial potency test used the agar-diffusion method using two types of microbial pathogens, namely the bacteria EPEC and the fungus Candida albicans. Each paper disk was given 50 µL of bacterial isolate, incubated at 37 0C for 24 hours and continued for 48 hours. The observed parameter is the clear zone formed around the paper disk. The results showed that cat root (A. indica L.) contains compounds that can inhibit the growth of EPEC bacteria and the fungus C. albicans. A good solvent to extract the active compounds contained in the cat root plant (A. indica L.) is distilled water. Treatment with aquadest extract with a concentration of 100% had the widest inhibition zone among other treatments, namely 6.8 mm against the growth of EPEC bacteria and ethanol extract with a concentration of 100% which was 3.8 mm against the growth of the fungus Candida albicans.

Antibiotic resistance of salmonella strains isolated from poultry products (eggs and organs) from markets and slaughter areas in the Bamako district

The aim of this study was to determine the antibiotic resistance of Salmonella strains isolated from poultry products from Bamako's markets and slaughter areas. It involved the analysis of 64 Salmonella strains isolated from poultry eggs and organs. The antibiotypic profile of these strains was determined using the Kirby-Bauer agar diffusion method and the recommendations of the Comité de l'antibiogramme de la société française de microbiologie (CA-SFM). This work resulted in high rates of resistance to imipenem (93.75%), followed by kanamycin (84.37%) and doxycycline (67.18%). In addition, low levels of resistance were observed to gentamicin (12.5%) and flumequine (26.56%). Sequencing of the complete genome of the isolated strains and the use of bioinformatics tools made it possible to obtain certain genes conferring antibiotic resistance, namely marB, marA, marC, marR, mdtG, mdtQ, folA, ksgA, rarD and STM169. Some of these genes are multi-resistant to antibiotics (marB, marA, marC).

Ternifoliasaponin, a new triterpenoid saponin from the roots of Gardenia ternifolia Schumach & Thonn (Rubiaceae)

A new triterpenoid saponin, Ternifoliasaponin (1), together with four known compounds (2–5) chikusetsusaponin IVa (2), chikusetsusaponin IVa methyl ester (3), bonushenricoside B (4) and Dianoside C (5) were isolated from roots of Gardenia ternifolia Schumach. & Thonn (Rubiaceae). The structures of isolated compounds were elucidated on the basis of spectroscopic analysis and chemical methods. The antibacterial activities of compounds (3), and (4) were performed by the Muller–Hinton agar diffusion method. The antimicrobial activities of the compounds were studied on Salmonella typhi (Enterobacteriaceae), Staphylococcus aureus and Pseudomonas aeruginosa microorganisms. Compound (3) at 25 mg/mL, showed moderately sensitive effect (8.0 ˂ DIZ ˂14.0 mm) on S. typhi, S. aureus and P. aeruginosa. Compound (4) at 25 mg/mL and compound (3) at 12.5 mg/mL exhibited moderately sensitive effect on S. typhi and S. aureus. Compound (4) inhibited moderately sensitive the S. typhi and P. aeruginosa colonies at 12.5 mg/mL.

In vitro antimicrobial activity of the crude extract of the endophytic bacterium Pseudomonas aeruginosa (SS93) isolated from Sapindus saponaria L.

Endophytes colonize the interior of plant tissues without causing any damage to their hosts. The plant Sapindus saponaria L., popularly known as ‘sabão-de-soldado’, presents a diversified endophytic microbiota and also medicinal properties. Endophytic microorganisms may produce secondary metabolites with different biotechnological properties. The present study aimed to evaluate the in vitro antibacterial and antifungal capacity of the crude extract of secondary metabolites produced by the endophytic bacteria P. aeruginosa SS93 isolated from S. saponaria leaves. The metabolites extract was obtained using the organic solvent ethyl acetate, and the antimicrobial activities were tested against six pathogenic bacteria (Enterococcus faecalis [ATCC 29212], Pseudomonas aeruginosa [ATCC 27853], Shigella flexneri [ATCC 12022], Salmonella enterica [CCCD a016], Escherichia coli [ATCC 25922], and Staphylococcus aureus [ATCC 25923]), and pathogenic fungi (Fusarium oxysporum, Glomerella sp., Sphaceloma sp., Fusarium solani, Maniliophtora perniciosa, and Sclerotinia sclerotiorum), by agar diffusion method. In the antibacterial assay, the best results were obtained against E. faecalis and S. aureus, where the formation of inhibition halos was observed in all tested concentrations, especially at 500 and 700 µg mL-1. Positive inhibitory activity against phytopathogenic fungi was observed, with the highest inhibition recorded against F. oxysporum (61.1%), followed by Sphaceloma sp. (55.7%), M. perniciosa (35.6%), F. solani (34.4%), and Glomerella sp. (30.4%).

Design, fabrication, and evaluation of green mesoporous hollow magnetic spheres with antibacterial activity

Hollow silica nanostructures are receiving more attention due to their special features such as low density and very high surface-to-volume ratio compared to other types of nanoparticles. In this research, an efficient method for the synthesis of hollow magnetic spheres with antibacterial properties is investigated. These hollow magnetic spheres are prepared in several steps and identified by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Energy-dispersive X-ray spectroscopy (EDS), Elemental mapping, High-resolution transmission electron microscopy (HRTEM), and vibrating-sample magnetometer (VSM) techniques. Also, the antibacterial property of magnetic hollow spheres is investigated by the agar diffusion method on the Acinetobacter baumannii, Staphylococcus epidermidis, Proteus mirabilis, Staphylococcus aureus, and Pseudomonas aeruginosa. Due to the high surface-to-volume ratio, their contact level with the surrounding environment is extremely high, which increases the effectiveness of their antibacterial properties. The results of FTIR bond analysis show that TEOS precursor particles established surface bonds with CTAB activators during the synthesis process, and the presence of SiOSi bonds in the range (600–1320 cm−1) indicates the formation of silicate chains. The size of the nanoparticles based on the HRTEM images was estimated to be approximately 40 nm. FESEM images confirmed the spherical shape of nanoparticles with an average size of 350 nm. The antibacterial feature, porous walls and empty space inside the spheres made it possible to facilitate and control the drug release and use it in medicine, especially for wound healing. Also, due to the magnetic properties of the manufactured nanospheres, they can be used in many ways in medical fields, especially in the treatment of cancer. In the continuation of the work, it is suggested to use Ag/Fe3O4@@ magnetic hollow mesoporous spheres (HMS) as a suitable drug carrier due to increasing the efficiency and control of drug delivery with the capabilities of targeting/responding to stimuli, increasing the speed and effect of the drug.