Reduction In Bacterial Counts Research Articles

Comparative evaluation of antimicrobial efficacy of bioactive glass, 1% chlorhexidine gluconate with calcium hydroxide and 1% chlorhexidine gluconate, as intracanal medicament in primary molars: An in vivo study

Aims: To compare the antimicrobial efficacy of Bioactive glass, combination of 1% Chlorhexidine gluconate gel and Calcium hydroxide powder and 1% Chlorhexidine gluconate gel as intracanal medicament in primary molars.Settings and Design: In vivo study design Methods and Material: The present study was conducted in the Department of Pediatric and Preventive Dentistry, Krishnadevaraya College of Dental Sciences and Hospital, Bengaluru. This study included 48 subjects within the age group ranging from 4-11 years who were indicated for multi visit Pulpectomy. These subjects were randomly divided into three experimental groups, containing sixteen samples per group. Group 1: Bioactive glass; Group 2:1% Chlorhexidine gel and Calcium hydroxide powder; Group 3:1% Chlorhexidine gel. Under rubber dam isolation, following lesion sterilization S0 sample was obtained. Following access opening and working length, sample S1 was obtained and the respective medicament was placed inside the canals after cleaning and shaping and a double seal was done with ZOE and GIC. Patient was recalled after a period of 5 to 7 days and the medicaments were flushed under isolation and sample S2 was obtained. Pulpectomy procedure was then completed. S0, S1, S2 samples were subjected to microbiological analysis and the total bacterial count in CFU/ml was calculated.Statistical analysis used: Kruskal Wallis Test and One-way ANOVA.Results: The mean percentage of reduction of bacterial count from S1- S2 (Before and after placement of medicament) with Group 1: Bioactive glass was 75.7%, with Group 2:1% Chlorhexidine gluconate and calcium hydroxide was 52% and Group 3:1% Chlorhexidine gluconate was 28.6%, revealing that bioactive glass has the superior antibacterial efficacy when compared with other groups. Antibacterial efficacy of bioactive glass was significant in both primary maxillary and mandibular first molar and second molar proving it to work best for all types of root anatomy in mixed dentition population. Superior clinical and microbiological results were found when bioactive glass was used as intracanal medicament in both intraoral and extra oral abscess cases in primary molars.Conclusions: Bioactive glass; intracanal medicament; primary dentition; primary molar; mixed dentition.

Development and characterization of catechin-in-cyclodextrin-in-phospholipid liposome to eradicate MRSA-mediated surgical site infection: Investigation of their anti-infective efficacy through in vitro and in vivo studies

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the prime pathogens responsible for surgical site infection (SSI). Treatment of SSI remains challenging because of resistant nature of MRSA, which is a major threat in recent years. Our previous work revealed the antibacterial potential of catechin isolated from cashewnut shell against MRSA. However, the application of catechin to treat MRSA-mediated SSI is hampered because of its poor solubility and low trans-dermal delivery. Hence, the present study focused on developing catechin-in-cyclodextrin-in-phospholipid liposome (CCPL) and evaluating its physicochemical characteristics and anti-infective efficacy through in vitro and in vivo models. Encapsulation of catechin with β-cyclodextrin and soybean lecithin was confirmed through UV–Vis spectroscopy, FTIR, and XRD techniques, while TEM imaging revealed the size of CCPL (206 nm). The CCPL displayed a higher level of water solubility (25.13%) and in vitro permeability (42.14%) compared to pure catechin. A higher level of encapsulation efficiency (98.9%) and antibacterial activity (19.8 mm of ZOI and 31.25 μg/mL of MIC) were noted in CCPL compared to the catechin/cyclodextrin complex. CCPL recorded significant and dose-dependent healing of the incision, significant reduction of bacterial count, improved epithelization, and effective prevention of inflammation in skin samples of SSI-induced Balb/c mice. Data of the present work suggest that the CCPL could be considered as a novel and potential candidate to mitigate MRSA-mediated SSI after clinical trials.

The impact of gel fingernail polish application on the reduction of bacterial viability following a surgical hand scrub.

To determine the effect of gel nail polish application on the reduction of bacterial viability immediately after a surgical hand scrub. Randomized controlled trial. Ten fingernails each from 40 female health care professionals and students. Participants' fingernails were randomized to receive no polish or gel nail polish during a manicure from a licensed manicurist. One day and 14 days after manicure, participants' fingernails were sampled before and after a surgical hand scrub with chlorhexidine gluconate. The samples for each fingernail were serially diluted, plated on a Trypsin sheep blood agar and MacConkey's agar plate, and incubated for 36 h. For each plate, bacterial colony forming units (CFU)/ml were determined. Mixed linear models were used to assess factors associated with the logarithmic reduction of viable bacterial counts from pre- to post-surgical scrub. In the final model, no association was detected between gel nail polish and reduction of viable bacterial count (p=.09). On Day 14, among longer nail lengths (2 to <3-mm and ≥3-mm), surgical scrubs resulted in greater reduction in bacterial counts in left-handed than right-handed participants (p < .01). Increasing nail length was correlated with increased CFU/ml post-scrubbing (p < .001). Application of gel nail polish did not seem to affect the ability of surgical scrub to reduce bacterial viability 1 and 14 days after a manicure. This study does not provide evidence to prevent application of gel nail polish on short fingernails in surgeons prior to surgical hand scrub with chlorhexidine gluconate.

Preoperative antisepsis in ophthalmic surgery (a review).

Endophthalmitis remains a serious complication following intraocular procedures. Preoperative prophylactic measures for endophthalmitis decrease the morbidity associated with this disease and represent a standard of care prior to ophthalmic surgery. The literature supports as measures for ocular antisepsis: povidone-iodine solution for ocular surface preparation, chlorhexidine in patients with iodine allergy and application of topical antibiotics. Povidone-iodine is regarded as the most effective antiseptic associated with significant reduction in ocular surface bacterial counts. Currently, the recommended preoperative management is the application of 5% povidone-iodine solution in the conjunctival fornix, prior to surgery. This paper reviews the preoperative measures for ocular antisepsis, used in order to decrease the risk of culture-proven endophthalmitis.

Treatment of dental plaque biofilms using photodynamic therapy: a randomised controlled study

IntroductionPhotodynamic therapy (PDT) is a treatment modality involving a dye that is activated by exposure to light of a specific wavelength in the presence of oxygen to form oxygen species causing localised damage to microorganisms.AimTo determine the most effective bactericidal incubation and irradiation times of erythrosine-based PDT on in vivo-formed dental plaque biofilms.MethodsA randomised controlled study; 18-healthy adult participants wearing intraoral appliances with human enamel slabs to collect dental plaque samples in two separate periods of two weeks each for use in arm-1 and arm-2. These accumulated dental plaque samples were treated with PDT under different experimental conditions. Incubation times with photosensitiser (erythrosine) of 15 min and 2 min were used in arm-1 and arm-2, respectively, followed by light irradiation for either 15 min (continuous) or as a fractionated dose (5 × 30 sec). Following treatment, percentage reductions of total bacterial counts were compared between the different groups. In addition, confocal laser scanning microscopy (CLSM) and LIVE/DEAD® BacLight™ Bacterial Viability Kit were used to visualise the effect of PDT on in vivo-formed biofilms.ResultsSignificant reductions in the percentage of total bacterial counts (~93–95%) of in vivo-formed biofilms were found when using either 2 min or 15min incubation times and applying 15 min continuous light. Although when applying fractionated light, there was more cell death when 15 min incubation time was used (~ 91%) compared with the 2 min incubation time (~ 64%). CLSM results supported these findings.ConclusionImproving the clinical usefulness of PDT by reducing its overall treatment time seems to be promising and effective in killing in vivo-formed dental plaque biofilms.

Fabrication of gelatin/silk fibroin/phage nanofiber scaffold effective against multidrug resistant Pseudomonas aeruginosa

Objective The alarming rise of multi-drug resistant (MDR) Pseudomonas aeruginosa has prompted the World Health Organization to consider it a serious threat to human health. Although phage (Phg), an effective antibacterial treatment option, can maintain long-term infectivity via lyophilized storage, freeze-drying can be expensive and time-consuming. Thus, we propose electrospun gelatin/fibroin (G/F) nanofibrous formulation for dehydrating and storing phage against MDR P. aeruginosa. Significance The formulation of phage within the nanofibrous structure of the electrospun G/F scaffold would result in antimicrobial activity against MDR P. aeruginosa leading to enhanced wound healing. Methods Phg effective against MDR P. aeruginosa was isolated, characterized and loaded within G/F nanofibers by electrospinning. Morphology, crystallinity and thermal stability as well as the antimicrobial activity and the biocompatibility of the developed G/F/Phg nanofibers were determined. Results Phg-loaded G/F nanofibers revealed an amorphous structure with good thermal stability at temperatures below 300 °C and exhibited effective antibacterial activity against MDR P. aeruginosa with ∼2 log reduction in the bacterial count which increased to ∼4 log reduction in bacterial count after 16 h as compared to both the G/F nanofibers and the negative control. Lack of cytotoxic effects on cultured fibroblasts supported the biocompatibility of G/F/Phg nanofibers. Conclusion The developed G/F/Phg nanofibers are able to maintain the viability of phage and represent a promising antimicrobial dressing for wounds infected with MDR P. aeruginosa.

Effect of Propolis and Pomegranate Extract Mouthwashes on Taste Alteration, Salivary pH and Antibacterial Activity in High Caries Risk Patients: A Randomized Control Trial

Dental caries prevention is the key to control dental caries worldwide problem nowadays. Chlorhexidine is the gold standard antibacterial agent but it has many side effects so natural products have been proposed as a safer alternative; Propolis and pomegranate are known with their great antibacterial properties.Aim: This study assessed taste alteration, salivary pH and antibacterial activity of propolis and pomegranate mouthwashes compared to chlorhexidine mouthwash in high caries risk patients.Materials and Methods: A total of 80 participantswere divided randomly into four groups, in a parallel group design. Group 1:propolis mouthwash, group 2: pomegranate mouthwash, group 3: chlorhexidine mouthwash and group 4: saline. Salivary sample was collected at baseline, immediately after mouthwash usage and after seven days. The pH of the collected saliva and streptococcus mutans bacterial count were assessed. Participants received a questionnaire to assess taste alteration on the seventh day. Statistical analysis took placeusing ANOVA/ Kruskal-Wallis and Wilcoxon tests.Results: Chlorhexidine has a significantly higher incidence of taste alteration compared to the other mouthwashes which showed statistically similar incidence. The highest salivary pH value was recorded after immediate usage of mouthwashes in all groups, after seven days there was no significant change in chlorhexidine and saline groups. There was no statistically significant difference between the total percentage reduction of bacterial count in all groups but with highest percentage of reduction after immediate usage.Conclusion: Propolis and pomegranate mouthwashes could be considered as an alternative to chlorhexidine mouthwash

Therapeutic Potential of Novel Mastoparan-Chitosan Nanoconstructs Against Clinical MDR Acinetobacter baumannii: In silico, in vitro and in vivo Studies.

PurposeAcinetobacter baumannii antibiotic resistant infections in high-risk patients are a great challenge for researchers and clinicians worldwide. In an effort to achieve potent bactericidal outcomes, a novel chitosan–mastoparan nanoconstruct (Mast-Cs NC) was designed and assessed for its therapeutic potential through in silico, in vitro and in vivo experimentation against clinical multidrug-resistant (MDR) A. baumannii.MethodsOptimized 3D structures of mastoparan and chitosan were coupled computationally through an ionic cross-linker to generate a circular ring of chitosan encasing mastoparan. The complex was assessed for interactions and stability through molecular dynamic simulation (MDS). Binding pocket analysis was used to assess the protease–peptide interface. Mast-Cs NC were prepared by the ionic gelation method. Mast-Cs NC were evaluated in vitro and in vivo for their therapeutic efficacy against drug-resistant clinical A. baumannii.ResultsMDS for 100 ns showed stable bonds between chitosan and mastoparan; the first at chitosan oxygen atom-46 and mastoparan isoleucine carbon atom with a distance of 2.77 Å, and the second between oxygen atom-23 and mastoparan lysine nitrogen atom with a distance of 2.80 Å, and binding energies of −3.6 and −7.4 kcal/mol, respectively. Mast-Cs complexes approximately 156 nm in size, with +54.9 mV zeta potential and 22.63% loading capacity, offered >90% encapsulation efficiency and were found to be geometrically incompatible with binding pockets of various proteases. The MIC90 of Mast-Cs NC was significantly lower than that of chitosan (4 vs 512 μg/mL, respectively, p<0.05), with noticeable bacterial damage upon morphological analysis. In a BALB/c mouse sepsis model, a significant reduction in bacterial colony count in the Mast-Cs treated group was observed compared with chitosan and mastoparan alone (p<0.005). Mast-Cs maintained good biocompatibility and cytocompatibility.ConclusionNovel mastoparan-loaded chitosan nanoconstructs signify a successful strategy for achieving a synergistic bactericidal effect and higher therapeutic efficacy against MDR clinical A. baumannii isolates. The Mast-Cs nano-drug delivery system could work as an alternative promising treatment option against MDR A. baumannii.

Moderations in performance, immunity, tissue architecture, and vaccine viability induced by water magnetization in broiler farms.

Background and Aim:Water magnetization contributes to increased molecular ionization and fluidity, which improves biological activities. This study tests the influence of magnetic water on the viability of the Newcastle vaccine and the survival of Escherichia coli and SalmonellaTyphimurium, as well as the influence of magnetic water in face of water impurities’ challenges on performance, immunity, and tissue architecture in broiler chickens.Materials and Methods:An in vitro 96-micro-well plate minimal inhibitory concentration was utilized to test the influence of water, saline, and magnetic water on Newcastle vaccine viability and E. coli O157:H7 and S. Typhimurium survival. The 245 experimental 1-day-old female Ross® 308 broilers used in this study were divided into seven groups of 35 birds each. Broilers were provided with magnetic drinking water (13,200 gausses) for 6 h daily from the 5th day and were challenged on days 14, 21, 28, and 35 using sodium chloride (700 mg/L), calcium sulfate (80 mg/L), lead acetate (500 mg/L), yeast extract 5% (5 mg/L), diazinon (2.5 mL/L), and E. coli O157:H7 (1.6 × 109 CFU/mL). A total of 2040 samples (96 diluent-Newcastle virus vaccine mixes, 96 microbial-magnetic water mixes, 231 sera, 231 intestinal swabs, and 1386 organ samples) were collected.Results:An in vitro trial revealed highly significant (p<0.01) declines of 94.13%, 84.53%, and 10.31% in the Newcastle vaccine titer in water, saline, and magnetic water, respectively, and 54.91% and 39.89% in E. coli O157:H7 and S. Typhimurium survival, respectively, after 4 h. In all challenged groups, broilers exhibited highly significant (p<0.01) increases in performance, carcass/organs weight, immunoglobulin G, immunoglobulin M, and Lactobacillus counts; significant improvement in tissue architecture and biochemical parameters; and highly significant (p<0.01) reductions in cortisol, superoxide dismutase, and total bacterial and Enterobacteriaceae counts.Conclusion:Magnetic water could maintain vaccine viability and vaccination efficiency, reduce microbial survival, and minimize the negative influence of all induced challenges.

Antimicrobial Effectiveness of Photodynamic Therapy, 5% Sodium Hypochlorite and 2% Chlorhexidine Gluconate in Root Canal Treated Teeth: A Clinical Study

Aim: To evaluate the effectiveness of photodynamic therapy (PDT), sodium hypochlorite (NaOCl) and chlorhexidine gluconate (CHO) in the endodontic re-treatment in the removing of microorganisms from previously filled infected root canals. Materials and Methods: The study samples consist of 54 root canal treated anterior teeth with apical periodontitis were randomly divided into three groups according to the disinfection protocol. Microbiological samples from the root canals were collected after removing the gutta-percha (S1) and following the endodontic re-treatment (S2) with either 5% NaOCl, 2% CHO or PDT procedure for 1 minute. Microbiological samples were cultivated on selective plates to assess the presence or absence of microbial growth and determine the average reduction of viable microorganisms. Results: Significant reduction in the total bacterial count in all the groups at post treatment ( P &lt; .001). PDT provided statistically higher (99.74%) elimination of Enterococcus faecalis in comparison to NaOCl (95%) and CHO (88%). Conclusions: The use of PDT in endodontic re-treatment led to the significant reduction of the remaining bacterial species. So, PDT can be used for routine endodontic disinfection in failed root canal cases.

Inhibition of LpxC Increases the Activity of Iron Chelators and Gallium Nitrate in Multidrug-Resistant Acinetobacter baumannii.

Infections caused by multidrug-resistant Acinetobacter baumannii would benefit from the development of novel treatment approaches. Compounds that interfere with bacterial iron metabolism, such as iron chelators and gallium nitrate, have previously been shown to have antimicrobial activity against A. baumannii. In this study, we characterize the effect of LpxC inhibitors on the antimicrobial activity of previously characterized iron chelators, 2,2′-bipyridyl (BIP) and deferiprone (DFP), and gallium nitrate (Ga(NO3)3) against A. baumannii reference strains and multidrug-resistant clinical isolates. The LpxC inhibitor LpxC-2 was synergistic with BIP for 30% of strains tested (FICI values: 0.38–1.02), whereas inhibition with LpxC-4 was synergistic with BIP for 60% of strains tested (FICI values: 0.09–0.75). In time–kill assays, combinations of BIP with both LpxC inhibitors demonstrated synergistic activity, with a more than 3 log10 reduction in bacterial counts compared to BIP alone. LpxC-2 was synergistic with Ga(NO3)3 for 50% of strains tested (FICI values: 0.27–1.0), whereas LpxC-4 was synergistic with Ga(NO3)3 for all strains tested (FICI values: 0.08–≤0.50). In time–kill assays, combinations of Ga(NO3)3 with LpxC-2 and LpxC-4 decreased the growth of both strains compared to each compound separately; however, only the combination with LpxC-4 met the defined criteria for synergy. These results identify a novel synergy between two antimicrobial classes against A. baumannii strains.

Gamma irradiation and storage effects on quality and safety of Himalayan paprika (Waer)

The present study was conducted to investigate the effect of gamma irradiation treatment (control, 3, 6, 9 kGy) on the changes in capsaicinoids, carotenoids, phenolic acids and microbial load of traditional Himalayan paprika during storage under ambient conditions. HPLC (High Performance Liquid Chromatography) results revealed that total capsaicinoids and phenolic acids increased significantly (p ≤ 0.05) with gamma irradiation and decreased significantly (p ≤ 0.05) during storage. With storage, dihydrocapsaicin exhibited more decrease (23.3%) compared to capsaicin (21.0%) in 9 kGy irradiated samples. However, carotenoids decreased significantly (p ≤ 0.05) with respect to both gamma irradiation and storage. Among carotenoids, capsorubin showed less decrease (19.2%) with storage when compared to capsanthin (29.9%), zeaxanthin (28.5%), beta-carotene (29.5%) and beta-cryptoxanthin (29.5%) in 9 kGy irradiated samples. The use of gamma irradiation for microbial decontamination resulted in 2 log reduction in bacterial count and 3 log reduction in yeast and mold count at a dose of 3 kGy. However, in samples irradiated at doses 6 kGy and 9 kGy, no microbial growth was observed up to 9 months of storage. The study elucidates quality and safety retention of irradiated processed paprika, enabling its potential commercial application in food products as a culinary ingredient.

Quality attributes enhancement of ready-to-eat hairtail fish balls by high-pressure processing

High-pressure processing (HPP) subject to 250 MPa for 5 min or 300, 350 MPa for 3 or 5 min was applied to pre-cooked hairtail (Trichiurus haumela) fish balls for manufacturing ready-to-eat (RTE) surimi products, while effects on quality attributes (microorganism, texture, color, freshness, protein structure, sensory, and water distribution) were investigated. The results indicated that safety and freshness of fish balls treated at 350 MPa for 5 min were significantly improved evidenced by the reduction of total bacterial count (from 726.67 to 7.33 CFU/g) and total volatile basic nitrogen content (from 3.45 to 0.93 mg N/100 g). Additionally, a moderate high-pressure treatment was beneficial for improving textural and sensory properties of hairtail fish balls, including higher springiness, cohesiveness and gel strength. However, a higher pressure (350 MPa) unfolded proteins, and changed the secondary structure of myofibrillar protein, resulting in the decrease of gel strength. Color changes caused by pressurization were within acceptable ranges. Low-field NMR (LF-NMR) results showed a reduction in water mobility and a transfer of immobilized water to bound water for pressure-induced samples. Overall, HPP at 300 MPa for 5 min is suggested for the development of RTE fish balls with favorable quality attributes.

The use of Vitally Active Cellulose Membranes for the Reduction of Pathogenic Bacterial Count in White Cheese

This study was designed to evaluate the effects of cellulose membranes produced by Acetobacter xylinum bacteria, after enrichment of the growth media with Alzahdy palm dates syrup to enhance cellulose production for reducing the contamination of locally-produced white cheese with pathogenic bacteria. Cellulose was vitally activated by incubation with both probiotics Lactobacillus acidophilus and Lactobacillus plantarum and the effectiveness of the produced cellulose membranes was measured by studying six characteristics: elongation, tensile strength, membrane rupture, permeability to oxygen, permeability to water vapor, and thickness (mm). The produced membranes showed remarkable functionality and characteristics for all studied tests. The results indicate that the cellulose membranes showed high antibacterial activity after incubation with Lactobacillus acidophilus and Lactobacillus plantarum for 24 and 48 hours against five different pathogenic bacteria, namely E. coli, S. aureus, Pseudomonas sp., B. cereus and S. typhymurim. Moreover, a positive result was obtained by reducing the number of these pathogenic bacteria after treating the white cheese with the produced cellulose membranes.

Silver‐doped sol‐gel borate glasses: Dose‐dependent effect on Pseudomonas aeruginosa biofilms and keratinocyte function

AbstractBorate‐based glasses have generated great interest for wound healing applications due to their ability to incorporate biologically therapeutic ions which can then be released at the site of repair attributable to their high dissolution rates. In this study, the anti‐bacterial activity and cytocompatibility of sol‐gel–derived silver‐doped borate glasses (AgBGs) of the compositional range (60)B2O3–(36)CaO–(4–x)P2O5–(x)Ag2O, where x = 0.0, 0.3, 0.5, and 1 (mol.%) were investigated, in vitro. The dose‐dependent anti‐bacterial activity of AgBGs was demonstrated against Pseudomonas aeruginosa under both planktonic conditions and pre‐formed biofilms, with up to 99.7% reduction in bacterial cell counts. Lower concentrations of ionic dissolution products from AgBGs were non‐toxic to keratinocytes, stimulating their growth and metabolic activity. Furthermore, compositions containing 0.3 and 0.5 mol.% Ag significantly accelerated the migration of keratinocytes at two different concentrations in an in vitro 2D wound healing model. In summary, these therapeutic AgBGs have demonstrated potential for accelerated wound healing.

Isolation and Characterization of Bacteriophages from Inland Saline Aquaculture Environments to Control Vibrio parahaemolyticus Contamination in Shrimp.

The online version contains supplementary material available at 10.1007/s12088-021-00934-6.

Toxic and Microbiological Effects of Iron Oxide and Silver Nanoparticles as Additives on Extended Ram Semen.

Simple SummaryArtificial insemination with extended semen is a reproductive biotechnological method promising quick genetic improvement and benefits for farmers. Semen collection in farm animals, including rams, is a procedure that takes place under unsterile conditions. Apart from certain bacteria, which are pathogenic and may be transmitted through semen to the female genital tract, causing clinical diseases, semen from healthy donors may also be contaminated during processing of the ejaculate. Consequently, ejaculate contamination with bacteria is inevitable. Antibiotics are a main constituent of semen extenders to avoid growth of bacteria present in ram semen and, subsequently, enhance reproductive performance. During the last decades, however, there is an increasing scientific interest about alternative agents to the conventional antibiotics, such as nanoparticles, to overcome bacterial resistance, which is a serious problem for human and veterinary medicine. Therefore, the aim of this study was to examine the effect of iron oxide and silver nanoparticles’ supplementation on bacterial proliferation control during ram semen processing, as well as their impact on sperm quality and functionality variables.The aim of the study was to investigate the effect of iron oxide (Fe) and silver (Ag) nanoparticles (NPs) on ram semen. A skim milk extender without antibiotics was used as a diluent of 21 ejaculates (8 rams; 2–3 ejaculates/ram). The groups of control (C; semen without NPs), Fe NPs (3.072 mg Fe3O4/mL semen), and Ag NPs (2.048 mg Ag-Fe/mL semen) were incubated (15 °C; 30 min), and then a magnetic field was used for NPs’ removal. Standard microbiological procedures were performed for all groups. Post-treated samples were stored (15 °C) for 24 h, and sperm variables (kinetics by computer assisted sperm analysis (CASA); viability; morphology; HOST; DNA integrity) were evaluated at 6 and 24 h. Semen data were analyzed by a mixed model for repeated measures and microbiological data with Student’s t-test for paired samples. At 6 h of storage, VCL and rapid movement-spermatozoa, and at 24 h, total/progressive motility and amplitude of lateral head displacement (ALH) were significantly decreased in group Ag compared to control. In group Fe, progressive/rapid movement-spermatozoa were significantly lower compared to control after 24 h of storage. Only in group Ag was a significant reduction of total bacterial count revealed. In conclusion, the examined Fe NPs demonstrated slight antibacterial effect, while the examined Ag NPs provided higher antibacterial properties accompanied by cytotoxicity.

Development of thermosensitive hydrogel wound dressing containing Acinetobacter baumannii phage against wound infections

With the emergence of multidrug resistance (MDR) bacteria, wound infection continues to be a challenging problem and represents a considerable healthcare burden. This study aims to evaluate the applicability of a phage loaded thermosensitive hydrogel in managing wound infections caused by MDR Acinetobacter baumannii, using IME-AB2 phage and MDR-AB2 as the model phage and bacteria, respectively. Excellent storage stability of the IME-AB2 phage in a ~18 wt% Poloxamer 407 (P407) hydrogel solution was first demonstrated with negligible titer loss (~0.5 log) in 24 months at 4 °C. The incorporated phage was released in a sustained manner with a cumulative release of 60% in the first 24 h. The in vitro bacterial killing efficiency of phage gel and phage suspension at 37 °C demonstrated >5 log10 CFU/ml reduction against A. baumannii. A comparable biofilm elimination capacity was also noted between the phage gel and phage suspension (59% and 45% respectively). These results suggested that the incorporation of phage into the hydrogel not only had insignificant impacts on the bacterial killing efficiency of phage, but also act as a phage depot to maintain higher phage titer at the infectious site for a prolong period for more effective treatment. We also found that the hydrogel formulation significantly suppressed microbial survival in an ex vivo wound infection model using pig skin (90% reduction in bacterial counts was achieved after 4 h treatment). In summary, our results demonstrated that the P407-based phage-loaded thermosensitive hydrogel is a simple and promising phage formulation for the management of wound infections.

Evolution of grain microbiota during hermetic storage of corn (Zea mays L.)

Respiration of biotic components of the grain ecosystem generates self-modified atmospheres (oxygen reduced and carbon dioxide enriched) during hermetic storage. The effect of temperature, moisture content and modified atmospheres on the evolution of maize microbiota is not entirely known. In this study, corn grain samples were conditioned to different moisture contents (14.3, 16.5 and 18.4%) and hermetically stored in glass jars at 15, 25 and 35 °C. Grain samples were collected at different stages of modified atmosphere evolution of each experiment: T0 (O2: 21% initial concentration); T1 (O2: 10%); T2 (O2: 0%); T3 (CO2 maximum concentration stabilized). Microbiota was quantified with Petri dish counts using selective growth media for different microbial groups. Additionally, ethanol, acetic acid and lactic acid were measured for monitoring anaerobic activity. Results indicated that there was a high correlation between water activity (aw) and the time to reach anaerobiosis (R2 of 0.85), the maximum CO2 concentration (R2 of 0.86), and the reduction of filamentous fungi and bacterial counts during hermetic storage (R2 of 0.72 and 0.48, respectively). A differential behavior of the hermetic storage was observed according to aw of the grain, and a general conceptual model is offered for its understanding. It was concluded that modified atmospheres reduced or inhibited microbial growth in stored corn, and that aw was the most influential factor in the time to reach anaerobiosis, maximum CO2 concentration, and the filamentous fungi and bacterial counts reduction during hermetic storage.

Effects of lemon and kiwi juice in reduction of some pathogens contaminating chicken breast meat

The unacceptable bad quality meat of chickens is a problem for the poultry industry. Therefore, the main objective of current study was improve the sensory, microbiological quality of row hen meat and inhibit the growth of Enterobacteriacea and Staphylococcus using natural juices of kiwi, lemon and their combination and to investigate the deterioration criteria and sensory quality of treated meat during refrigerated storage. Five groups were marinated in marinade solutions containing fruit juices as follow: the 1st group was containing 5% kiwi juice, the 2nd group was containing 10% kiwi juice, the 3rd group was containing 0.04% lemon juice, the 4th group was containing 0.2% lemon juice, the 5th group was containing combination of 10% kiwi juice and 0.2% lemon juice and the 6th group was used as acontrol without kiwi or lemon, all groups were stored at 4ᵒC. Results revealed that using lemon 0,04%, lemon 0.2%, kiwi5%, kiwi10% and mix (lemon 0.2% + kiwi 10%) in zero day made reduction in total bacterial count by 95.3%, 98%, 73.9%, 89.3% and 93.3% respectively and reduction in count of Enterobacteriacae by 58%, 99.8%, 89.23%, 95.64% and 95.51% respectively and reduction in Staphylococcus count by 65.15%, 96.74%, 60.60%, 93.18% and 93.68 respectivly so, it can be used as natural preservatives to control food poisoning diseases , increase shelf life on chicken meat.