Reduction In Bacterial Counts Research Articles

2D TiO2 nanosheets decorated via sphere-like BiVO4: a promising non-toxic material for liquid phase photocatalysis and bacterial eradication.

An in-depth investigation was conducted on a promising composite material (BiVO4/TiO2), focusing on its potential toxicity, photoinduced catalytic properties, as well as its antibiofilm and antimicrobial functionalities. The preparation process involved the synthesis of 2D-TiO2 using the lyophilization method, which was subsequently functionalized with sphere-like BiVO4. Finally, we developed BiVO4/TiO2 S-scheme heterojunctions which can greatly promote the separation of electron-hole pairs to achieve high photocatalytic performance. The evaluation of concentration- and time-dependent viability inhibition was performed on human lung carcinoma epithelial A549 cells. This assessment included the estimation of glutathione levels and mitochondrial dehydrogenase activity. Significantly, the BiVO4/TiO2 composite demonstrated minimal toxicity towards A549 cells. Impressively, the BiVO4/TiO2 composite exhibited notable photocatalytic performance in the degradation of rhodamine B (k =0.135 min-1) and phenol (k = 0.016 min-1). In terms of photoinduced antimicrobial performance, the composite effectively inactivated both gram-negative E. coli and gram-positive E. faecalis bacteria upon 60-min of UV-A light exposure, resulting in a significant log6(log10CFU/mL) reduction in bacterial count. These promising results can be attributed to the unique 2D morphology of TiO2 modified by sphere-like BiVO4, leading to an increased generation of (intracellular)hydroxyl radicals, which plays a crucial role in treatments of both organic pollutants and bacteria.

Evaluation of antibacterial activity of an experimental dental adhesive containing synthesized quaternary ammonium compound: in vitro study

BackgroundDental adhesives with immobilized antibacterial agents are formulated to combat bacterial invasion along the tooth-restoration interface. This study aims to evaluate the antibacterial effect of synthesized quaternary ammonium compound (QAC) incorporated into commercial dental adhesive.MethodsQAC was synthesized from 2-(Dimethylamino) ethyl methacrylate and 1-Bromobutane and characterized using CHN (Carbon, Hydrogen, Nitrogen), FTIR (Fourier transform infrared) and H+NMR (Proton nuclear magnetic resonance) analyses. The synthesized QAC was assessed for its cytotoxicity and its antibacterial activity against S. mutans using disc diffusion method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), time-kill kinetics test, and TEM imaging. The QAC was added to the primer of a commercially available adhesive (OptiBond XTR) at two concentrations; 20 and 40 mg mL−1 representing the MIC and MBC, respectively. The antibacterial properties of the experimental adhesives, commercial antibacterial adhesive Clearfil SE Protect containing 12-methacryloyloxydodecylpyridinium bromide (MDPB), and commercial vehicle (OptiBond XTR) were compared using time-kill kinetics test. Statistical analysis by ANOVA followed by tukey post-hoc test (P < 0.05).ResultsDisc diffusion and time-kill kinetics tests showed potent antibacterial action of QAC, both in the unpolymerized and the cured forms. MIC and MBC were 20 and 40 mg mL−1 respectively. There was no statistically significant difference between experimental adhesives and Clearfil Protect with more than 99% reduction in bacterial count, while OptiBond XTR showed no bacterial killing up for up to 10 h.ConclusionsThe synthesized QAC added to a commercially available adhesive imparted antibacterial properties, thus providing an affordable adhesive system to the local market.

Activities of aztreonam in combination with several novel β-lactam-β-lactamase inhibitor combinations against carbapenem-resistant Klebsiella pneumoniae strains coproducing KPC and NDM.

Isolates coproducing serine/metallo-carbapenems are a serious emerging public health threat, given their rapid dissemination and the limited number of treatment options. The purposes of this study were to evaluate the in vitro antibacterial activity of novel β-lactam-β-lactamase inhibitor combinations (BLBLIs) against carbapenem-resistant Klebsiella pneumoniae (CRKP) coproducing metallo-β-lactamase and serine-β-lactamase, and to explore their effects in combination with aztreonam, meropenem, or polymyxin in order to identify the best therapeutic options. Four CRKP isolates coproducing K. pneumoniae carbapenemase (KPC) and New Delhi metallo-β-lactamase (NDM) were selected, and a microdilution broth method was used to determine their susceptibility to antibiotics. Time-kill assay was used to detect the bactericidal effects of the combinations of antibiotics. The minimum inhibitory concentration (MIC) values for imipenem and meropenem in three isolates did not decrease after the addition of relebactam or varbobactam, but the addition of avibactam to aztreonam reduced the MIC by more than 64-fold. Time-kill assay demonstrated that imipenem-cilastatin/relebactam (ICR) alone exerted a bacteriostatic effect against three isolates (average reduction: 1.88 log10 CFU/mL) and ICR combined with aztreonam exerted an additive effect. Aztreonam combined with meropenem/varbobactam (MEV) or ceftazidime/avibactam (CZA) showed synergistic effects, while the effect of aztreonam combined with CZA was inferior to that of MEV. Compared with the same concentration of aztreonam plus CZA combination, aztreonam/avibactam had a better bactericidal effect (24 h bacterial count reduction >3 log10CFU/mL). These data indicate that the combination of ATM with several new BLBLIs exerts powerful bactericidal activity, which suggests that these double β-lactam combinations might provide potential alternative treatments for infections caused by pathogens coproducing-serine/metallo-carbapenems.

Antimicrobial efficacy of two commercially available herbal products with and without ultrasonic activation in primary endodontic infections: A randomized clinical trial.

Effective irrigation is crucial for successful endodontic treatment. Traditional irrigants like sodium hypochlorite (NaOCl) have been widely used, but there is a growing interest in exploring natural alternatives for their potential antimicrobial properties. The study aims to compare the antimicrobial efficacy of Neem, Bitter Gourd, and NaOCl, with and without ultrasonic activation in managing primary endodontic infections. Ninety patients were randomly assigned six groups (n = 15) Group 1: NaOCl, Group 2: NaOCl with passive ultrasonic irrigation (PUI), Group 3: Neem juice, Group 4: Neem juice with PUI, Group 5: Bitter gourd juice, and Group 6: Bitter gourd juice with PUI. Bacteriological samples were collected before (S1) and after (S2) shaping, plated on brain heart infusion agar, and colony counting was done after 24 h. Shapiro-Wilk test, one-way ANOVA, post hoc Tukey analysis, and paired t-test. All the groups demonstrated a significant reduction in bacterial count. Groups with PUI (2, 4, 6) demonstrated higher mean bacterial reduction than their counterparts without PUI (1, 3, 5). Neem and Bitter gourd juices, particularly when used with PUI, demonstrated antimicrobial efficacy comparable to NaOCl with PUI.

Alginate and Chitosan-Based Hydrogel Enhance Antibacterial Agent Activity on Topical Application.

Untreated topical infections can become chronic, posing serious health issues. Optimal skin adherence is crucial in addressing such infections. In this context, chitosan and alginate emerge as promising candidates for use as a foundation in the development of topical hydrogels. The aim of this review is to examine the literature on topical hydrogel formulations that use chitosan and alginate as foundations, specifically in the context of topical antibacterial agents. The research methodology involves a literature review by examining articles published in databases such as PubMed, Scopus, ScienceDirect, and Google Scholar. The keywords employed during the research were "Alginate", "Chitosan", "Hydrogel", and "Antibacterial". Chitosan and alginate serve as bases in topical hydrogels to deliver various active ingredients, particularly antibacterial agents, as indicated by the search results. Both have demonstrated significant antibacterial effectiveness, as evidenced by a reduction in bacterial colony counts and an increase in inhibition zones. This strongly supports the idea that chitosan and alginate could be used together to make topical hydrogels that kill bacteria that work well. In conclusion, chitosan and alginate-based hydrogels show great potential in treating bacterial infections on the skin surface. The incorporation of chitosan and alginate into hydrogel formulations aids in retaining antibacterial agents, allowing for their gradual release over an optimal period. Therefore, hydrogels specifically formulated with chitosan and alginate have the potential to serve as a solution to address challenges in the treatment of topical bacterial infections.

The effect of nano silver fluoride, self-assembling peptide and sodium fluoride varnish on salivary cariogenic bacteria: a randomized controlled clinical trial

ObjectivesTo compare the antibacterial effect of Nanosilver Fluoride varnish (NSF) varnish, P11-4 and Sodium Fluoride (NaF) varnish against salivary Streptococcus mutans (S. mutans) and Lactobacilli.Methods66 patients aged 10–24 years old were randomly assigned to receive single application of NSF, P11-4 or NaF varnish. Baseline unstimulated saliva samples were collected before the agents were applied and S.mutans and Lactobacilli colony forming units (CFU) were counted. After one, three and six months, microbiological samples were re-assessed. Groups were compared at each time point and changes across time were assessed. Multivariable linear regression compared the effect of P11-4 and NSF to NaF on salivary S. mutans and Lactobacilli log count at various follow up periods.ResultsThere was a significant difference in salivary S. mutans log count after 1 month between P11-4 (B= -1.29, p = 0.049) and NaF but not at other time points nor between NSF and NaF at any time point. The significant reduction in bacterial counts lasted up to one month in all groups, to three months after using P11-4 and NaF and returned to baseline values after six months.ConclusionIn general, the antimicrobial effect of P11-4 and NSF on salivary S. mutans and Lactobacilli was not significantly different from NaF varnish. P11-4 induced greater reduction more quickly than the two other agents and NSF antibacterial effect was lost after one month.Clinical relevanceNSF varnish and P11-4 have antimicrobial activity that does not significantly differ from NaF by 3 months. P11-4 has the greatest antibacterial effect after one month with sustained effect till 3 months. The antibacterial effect of NSF lasts for one month. NaF remains effective till 3 months.Trial RegistrationThis trial was prospectively registered on the clinicaltrials.gov registry with ID: NCT04929509 on 18/6/2021.

Optimizing in vitro phage-ciprofloxacin combination formulation for respiratory therapy of multi-drug resistant Pseudomonas aeruginosa infections

Respiratory infection caused by multi-drug resistant (MDR) Pseudomonas aeruginosa is challenging to treat. In this study, we investigate the optimal dose of anti-pseudomonas phage PEV31 (103, 105, and 108 PFU/mL) combined with ciprofloxacin (ranging from 1/8× MIC to 8× MIC) to treat the MDR P. aeruginosa strain FADD1-PA001 using time-kill studies. We determined the impact of phage growth kinetics in the presence of ciprofloxacin through one-step growth analysis. Single treatments with either phage PEV31 or ciprofloxacin (except at 8× MIC) showed limited bactericidal efficiency, with bacterial regrowth observed at 48 h. The most effective treatments were PEV31 at multiplicity of infection (MOI) of 0.1 and 100 combined with ciprofloxacin at concentrations above 1× MIC, resulting in a >4 log10 reduction in bacterial counts. While the burst size of phage PEV31 was decreased with increasing ciprofloxacin concentration, robust antimicrobial effects were still maintained in the combination treatment. Aerosol samples collected from vibrating mesh nebulization of the combination formulation at phage MOI of 100 with 2× MIC effectively inhibited bacterial density. In summary, our combination treatments eradicated in vitro bacterial growth and sustained antimicrobial effects for 48 h. These results indicated the potential application of nebulization-based strategies for the combination treatment against MDR lung infections.

Eco-Friendly Antibacterial Finish from Ghamra and Apamarga Leaf Extract for Textile Application

ABSTRACT The aim of the present study was to develop eco-friendly antibacterial finish from Ghamra and Apamarga leaf extract and its application on textile. Aqueous and methanol extracts from Ghamra and Apamarga leaf had been applied to cotton fabric using pad dry cure method. Antibacterial efficacy of finished fabric samples were tested against Bacillus cereus and Pseudomonas aeruginosa and counted quantitatively by AATCC-100 test method. For testing the efficacy of finish, the samples were inoculated with selected bacterium and further tested to check their bacterial resistance by calculating the percentage reduction in bacterial count. The observations were taken after 24, 48, 72, and 96 hours of inoculation. The results revealed that samples finished with Ghamra and Apamarga leaf extracts showed 100% reduction after 24 hours of inoculation against both bacterial strains, respectively. After 48 hours, it gradually decreased and after 96 hours it decreased to 94.5% and 94.1% against Bacillus cereus and 94.2% and 94% against Pseudomonas aeruginosa in treated samples, respectively. The results also indicated that samples finished with Ghamra and Apamarga leaf extracts provided excellent ultraviolet protection, i.e. 44.51 and 45.37 as exhibited by higher UPF values. The surface morphological studies using SEM showed some fibrillation.

Target attainment of intravenous lefamulin for treatment of acute bacterial skin and skin structure infections.

Lefamulin is a pleuromutilin antibiotic approved for the treatment of community-acquired bacterial pneumonia (CABP). Its spectrum of activity, good penetration into soft tissues and low rates of cross-resistance also make lefamulin a potentially valuable option for treatment of acute bacterial skin and skin structure infections (ABSSSIs). A Phase 2 trial of lefamulin for ABSSSI indicated similar efficacy of 100 and 150 mg q12h IV dosing regimens. In the present study, the potential of lefamulin for this indication was further evaluated from a translational pharmacokinetic/pharmacodynamic perspective. PTA was determined for various dosages using Monte Carlo simulations of a population pharmacokinetic model of lefamulin in ABSSSI patients and preclinical exposure targets associated with bacteriostasis and a 1-log reduction in bacterial count. Overall target attainment against MSSA and MRSA was calculated using lefamulin MIC distributions. Overall attainment of the bacteriostasis target was 94% against MSSA and 84% against MRSA for the IV dosage approved for CABP (150 mg q12h). Using the same target, for the 100 mg q12h regimen, overall target attainment dropped to 68% against MSSA and 50% against MRSA. Using the 1-log reduction target, overall target attainment for both regimens was <40%. Lefamulin at the currently approved IV dosage covers most Staphylococcus aureus isolates when targeting drug exposure associated with bacteriostasis, suggesting potential of lefamulin for the treatment of ABSSSIs. Lefamulin may not be appropriate in ABSSSI when rapid bactericidal activity is warranted.

Antimicrobial Efficacy of Simvastatin and Double Antibiotic Paste as Intracanal Medicaments: A Randomised Clinical Study

Abstract Introduction: Root canal debridement, irrigation and a microorganism-free environment are key factors in the success of root canal treatment. Intracanal medicaments are used to enhance root canal disinfection. Simvastatin is derived from lovastatin and is a semisynthetic medication. This study compares and evaluates the effect of simvastatin and double antibiotic paste (DAP) as an intracanal medicament in single-rooted teeth with apical periodontitis using colony-forming units (CFUs)/ml. Materials and Methods: Twenty-eight patients with single-rooted teeth diagnosed with apical periodontitis were selected. Under aseptic conditions, patency was gained, sterile saline solution was deposited in the canal and the first sample (S1) was collected. Cleaning and shaping were then carried out following an appropriate technique depending on the configuration of the canal. After irrigation and biomechanical preparation, teeth were randomly assigned to two different groups, and the test intracanal medicament was applied to the root canals. Coronal openings were sealed with temporary restorative cement. The second sample (S2) was collected after 7 days. The samples obtained were checked for a reduction in the bacterial load. They were incubated aerobically for 48 h, and the CFUs were calculated. The Mann–Whitney U and Wilcoxon’s signed-rank tests were used to analyse the results statistically. Results: A significant reduction in bacterial count was present after administration of the intracanal medicament. On intergroup comparison, there was no statistically significant difference in bacterial decrease between the two groups. Comparatively, the mean reduction in the bacterial count was higher in the DAP group. Conclusion: It can be concluded that DAP and simvastatin were effective in the reduction of the bacterial count in single-rooted teeth diagnosed with apical periodontitis. However, DAP demonstrated a better performance in the reduction of bacterial counts.

Antibacterial Effect of Basil (Ocimum basilicum) and Table Salt as Alternative Disinfectants against Staphylococcus aureus

This study was undertaken to evaluate the potency of basil (Ocimum basilicum) extract and table salt as alternative disinfectants based on their effect in inhibiting bacterial proliferation. A sample of bacteria (Staphylococcus aureus) with an initial mean density of 1.35 x 103 CFU/mL was used as the bacterial test culture. Treatments included basil extract (T1), table salt (T2), ethanol (T3, positive control) and distilled water (T4, negative control). The antibacterial effect of the treatments was evaluated in terms of the measurement of the zones of inhibition which was further validated by monitoring the mean recovery counts of bacteria post-application with the treatments given at different concentrations (100, 50, 25 and 10%). The results showed that the larger diameter of the zones of inhibition (with mean measurements that ranged from 17.65 to 20.98 mm) was related to the application of basil extract, table salt and ethanol applied at 100% concentration compared with the 50% (mean measurements ranged from 14.03 to 17.67 mm) underscoring the minimum inhibitory concentration of the candidate disinfectants at 50%. There was a comparable significant reduction of bacterial recovery counts associated with the application of basil extract and ethanol only at 3 h that were not sustained until 6 h. The results indicated that basil extract and table salt at the prescribed concentrations could be used and therefore recommended as disinfectants.

In vitro evaluation of three engineered multispecies endodontic biofilms on a dentinal disk substrate

The aim of this study was the development of a complex multispecies endodontic biofilm using Candida albicans, Proteus mirabilis and Pseudomonas aeruginosa on a biofilm of Enterococcus faecalis in a dentinal substrate design. The endodontic pathology is a biofilm-mediated infection, and the aim of root canal therapy is to reduce, as much as possible, the bacterial population. Thus, it is important to develop a laboratory endodontic biofilm to test the effect of new irrigation and obturation techniques on reduction of bacterial count. The culture of Enterococcus faecalis from ATCC 29212 began with aerobic cultivation on blood agar, followed by transfer to Brain Heart Infusion (BHI) broth with 5% sucrose. Incubation occurred in a shaker at 37 °C for 24 h, followed by an additional 24-h static phase. After 10 d, Proteus mirabilis, Pseudomonas aeruginosa, and Candida albicans were introduced sequentially in three distinct groups. Group 1: the order of addition was Candida albicans, Proteus mirabilis, and Pseudomonas aeruginosa; Group 2: the order was Pseudomonas aeruginosa, Candida albicans, and Proteus mirabilis; and Group 3: Proteus mirabilis, Pseudomonas aeruginosa, and Candida albicans. After 16 days, the biofilm was carefully extracted, transferred to sterile BHI, and dissected using a sterile needle technique. Subsequently, an optical density test, bacterial counts, and colony enumeration were performed on various agar plates. Group 2 in which Pseudomonas aeruginosa was added directly after Enterococcus faecalis followed by Candida albicans and Proteus mirabilis showed significantly greater total bacterial count than the other two groups.

Design and evaluation of antibacterials crosslinked chitosan nanoparticle as a novel carrier for the delivery of metronidazole to treat bacterial vaginosis

Bacterial vaginosis (BV) is a recurring, chronic infection that is difficult to treat due to the limited bioavailability of antimicrobials within vaginal epithelial cells. Vaginal administration, because of lower dosing and systemic exposure offers a viable option for treating vaginal infections. In this study, Metronidazole-loaded chitosan nanoparticles were synthesised employing borax (BX) or tannic acid (TA) as an antimicrobial crosslinking agent for treating BV. The prepared NPs were characterized for various physical, physicochemical, pharmaceutical, thermal and antibacterial properties. Morphological investigation revealed that nanoparticles prepared from 0.5 % w/v chitosan, 1.2 % w/v BX, and 0.4 % w/v metronidazole (MTZ) were non-spherical, with particle sizes of 377.4 ± 37.3 nm and a zeta potential of 34 ± 2.1 mV. The optimised formulation has MIC values of 24 ± 0.5 and 59 ± 0.5 μg/mL, against Escherichia coli (E.coli) and Candida albicans (C.albicans) respectively. The results of DSC and XRD demonstrated no change in the physical state of the drug in the finished formulation. Under simulated vaginal fluid, the optimised formulation demonstrates a cumulative drug release of about 90 % within 6h. The prepared borax crosslinked NPs exhibit anti-fungal activities by inhibiting ergosterol synthesis. The in-vivo antibacterial data indicated a comparable reduction in bacterial count compared to the marketed formulation in female Swiss albino mice treated with optimised nanoparticles. According to histopathological findings, the prepared nanoparticle was safe for vaginal use. Based on the experimental findings, it was concluded that MBCSNPs, due to their good physiochemical and antimicrobial properties, could serve as a potential topical alternative for treating BV and reducing fungal infection.

Diode laser targeting red-complex bacteria in periodontitis: a systematic review.

This systematic review examines the effectiveness of diode laser irradiation in reducing the levels of red complex bacteria as well as periodontal parameters of pocket depth and clinical attachment level. We conducted electronic searches across databases such as Scopus, Embase, Medline, and Web of Science databases in July 2022. Randomized controlled trials that evaluated the reduction of red-complex bacteria in patients with periodontitis using diode lasers were included. The primary focus was the reduction in the microbial count of red complex bacteria, whereas probing depth and attachment level were considered secondary outcomes. Articles in languages other than English were excluded. Study quality was assessed based on the Cochrane Handbook for Systematic Reviews of Interventions and the ROB2 tool. After searching the databases, eight independent studies were included, with a sample size of 210 subjects. The average age group of the study population was 30-60 years, and there was a lack of consensus on the antimicrobial effect of diode lasers. Out of the eight studies, four studies reported no significant difference in the levels of red complex bacteria before and after laser application. Three studies reported significantly lower levels of red complex bacteria in the intergroup comparison. One study reported that laser had no significant effect on intergroup bacterial levels. The combination of diode laser irradiation with scaling reduced the count of red complex bacteria and improved the clinical parameters, although not significantly. Based on the limited evidence available, the adjunctive use of diode laser for scaling and root planning may provide some additional benefit in terms of reduction of red complex bacterial count and clinical parameters. Further well-designed trials and the use of objective measures are necessary before outlining universal guidelines for best practice. The adjunctive use of diode laser in non-surgical periodontal therapy may provide a reduction in the red complex microbial count and improvement in clinical parameters, decreasing the need for periodontal surgery.

Efficacy of Neem Leaves Extract and Aloe Vera as Antimicrobial in Hand Sanitizer

Since the coronavirus disease pandemic of 2019 (COVID-19) is spreading quickly around the world, 99% alcohol-based hand sanitizer (ABHS) is utilized to minimize disease transmission. During the COVID-19 outbreak, isopropyl supply becomes limited. Herbal based hand sanitizers were used as an alternative way during pandemic to reduce the spreading of COVID-19. This study aimed to evaluate the efficacy of neem leaves extract and aloe vera as antimicrobials for Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria which can readily be found on the hands. Moreover, 30% isopropyl alcohol, citrus lemon oil, essential oil and vitamin E oil were also added in the formulations. Four different hand sanitizers were formulated which labelled as A1, A2, A3 and A4. The initial formulation, A1, is said to be the most effective because it contains the highest amount of neem leaf extract and aloe vera, and it is followed by A2, which contains less neem leaf extract and aloe vera. A3 does not contain neem leaf extract, while A4 does not contain aloe vera. All formulations contained the same amount of isopropyl alcohol, essential oil, vitamin E oil, and citrus lemon. Streaking methods on Tryptic Soy Agar plate and nutrient agar plate were used to evaluate the effectiveness of hand sanitizer against S. aureus and E. coli bacteria. The total colony forming unit (CFU) and percentage of effectiveness were calculated to compare the antimicrobial activity of all the formulations. The results revealed that a significant reduction in total bacterial colony counts of microbes after treatment with the formulations. Besides, pH value for A1, A2, A3 and A4 were also evaluated, and the results were 5.2, 5.3, 4.8, and 5.5 respectively. Among all four formulations, A1 showed the highest efficiency of microbial disinfectant for both S. aureus and E. coli bacteria by showing the reduction of microbes for 94.55% and 97.27% respectively since A1 contains the highest amount of neem leaves extract and aloe vera. It also has a skin-friendly pH value of 5.2 which is slightly acidic to control the bacterial infection and applicable since it is within the pH range of 4.5 to 6.5 found in human skin.

Possibility of Prolonging Chicken Meat Shelf Life by Coating with Protein Concentrate of Quinoa Seeds

The research encompassed the production of protein casings derived from concentrated quinoa seed protein at varying concentrations (2%, 4%, 6%, 8%). The objective was to investigate the mechanical characteristics of the produced casings and their potential application in packaging refrigerated chicken breast pieces at a temperature of 4°C, with the aim of extending the storage duration for different time intervals (10, 5, 15 days). The findings pertaining to the mechanical properties of the protein casings being investigated revealed that the thickness of the membrane, tensile strength, elongation, and solubility exhibited an upward trend as the concentration increased. The findings of the microbial analysis also indicated that the application of protein casings derived from quinoa seed protein concentrate, at concentrations of 6% and 8%, on chicken breast pieces and subsequent refrigeration at 4°C, resulted in a significant reduction in the total bacterial count and the count of psychrophilic bacteria, in comparison to the control treatment where chicken pieces were left uncoated. In addition, it was observed that chicken breast portions that were coated with protein coatings exhibited no growth of coliform bacteria during the storage period, in contrast to the uncoated counterparts. The emergence of the phenomenon was observed on the tenth day of the storage period. The application of protein films on chicken breast parts resulted in a notable reduction in both the peroxide number (PV) and the value of thiarebiobutyric acid (TBA) as compared to the uncoated control treatment. The control treatment exhibited the highest values on the 15th day of refrigerated storage.

Innovative high power short time microwave finish drying cum decontamination method for producing hot curry spice mix (Garam Masala) with enhanced quality characteristics

Garam Masala is a mixture of ground spices commonly used in Indian and some Asian cuisines. Garam Masala risks microbial contamination due to poor hygienic conditions during various stages, including harvesting, processing, and storage. Moreover, its phytochemicals and antioxidant capacity need to be enhanced for better application in curry preparation and other recipes. The Garam Masala generally has a high microbial load and relatively higher moisture content (10-12% wet basis). The product having such a high moisture content is not shelf stable for longer durations due to its vulnerability to microbial growth. Therefore, an innovative high power short time finish drying cum decontamination method using microwaves (2.45 GHz) for Garam Masala was developed. Garam Masala was subjected to three different levels of microwave power density (10, 15, and 20 W/g) for 60 s. The best microbial load treatment protocol was also implemented, which consisted of applying 20 W/g for a duration of 60 s, followed by 6 cycles of 10 s “ON” and 5 s “OFF”. Drying kinetics were studied, and the Page model was found to be the best-fitting model. Microwave treatment exhibited a significant (p < 0.05) reduction in the total aerobic mesophilic bacterial count (2.79 log) and Bacillus cereus (1.83 log). The results also demonstrated that 15 W/g treatment enhanced the total phenolics, flavonoids content, and antioxidant capacity. No significant color changes were found between the untreated and treated samples. Therefore, it was concluded that a high power short time microwave finish drying cum decontamination method can control the microbial load and enhance the chemical characteristics in Garam Masala.

Production and characterization of plantaricin Y11 from &lt;i&gt;Lactiplantibacillus Plantarum&lt;/i&gt; strain y11 (MW642245.1) isolated from Nigerian food samples and their applications in preserving milk

Bacteriocin from lactic acid bacterium (LAB) was characterized and its biopreservation assay carried out using conventional methods and integrative approaches. About 66.7% (n=180) of the bacterial strains isolated from twelve different fermented/non-fermented food products were potential LAB strains by biochemical characterization. The highest bacteriocin producing strain was selected and confirmed with 16S rRNA sequencing and submitted to GenBank of National Center for Biotechnology Information as Lactiplantibacillus plantarum strain Y11 (Accession number: MW642245.1). Polymerase Chain Reaction (PCR) revealed the presence of virulence genes (cytotoxin K and haemolysin C) in L. plantarum Y11. The bacteriocin produced was labelled as plantaricin Y11 with molecular weight of 1540 Da, amino acid sequence was NSHGTADYCVMWLIXK, and possessed the merits of wide pH stability (2–10), high thermal stability and sensitivity to protease. The bacteriocin showed wide spectrum of activity against bacterial reference strains with bacteriocin activity ranging from 3200Au/mL to 6400Au/mL. Preservative potentials of the bacteriocin compared favourably with sodium benzoate in milk, inhibiting bacterial and fungal load compared to the control. There was log reduction of aerobic mesophilic bacterial count of 8.02±0.15 and 8.43±0.21 Log 10 CFU/mL in milk treated with plantaricin Y11 and sodium benzoate, respectively. The log reductions of fungal count in plantaricin Y11 and sodium benzoate treated milk ≥4.41±0.11 and ≥3.1±0.2 Log 10 CFU/mL respectively. The plantaricin Y11 was then classified as class IIa in bacteriocin classification schemes and it sustained some organoleptic conditions of milk making it a promising candidate for safe bio-preservatives.

Comparison of the Bacterial Inactivation Efficiency of Water Activated by a Plasma Jet Source and a Pin-to-Pin Electrode Configuration Source

In this comparative study, the bacterial inactivation efficiency of plasma-activated water (PAW) generated by two distinct plasma reactors, one utilizing a nitrogen plasma jet electrode and the other a hybrid argon plasma reactor, was explored. The present study involved the assessment of antimicrobial activity against suspensions of three Gram-positive and three Gram-negative bacterial strains in their planktonic cell state. Bacterial suspensions were introduced into PAW five days after generation. Subsequently, the viability of the bacteria was assessed at various time intervals, specifically at 0.5, 1, 3, 5, 10, and 24 h, in order to evaluate the effect of inactivation. Structural changes in bacteria after PAW treatment were assessed using a scanning electron microscope (SEM). The physicochemical properties of PAW, including pH, conductivity, and concentrations of H2O2, NO2−, and NO3− during aging were measured. The present study demonstrated the effective inactivation of the tested bacterial strains by PAW. Gram-positive bacteria displayed greater resistance compared to Gram-negative species, with the lowest reductions in bacterial counts observed for B. cereus, and the highest for Escherichia coli O157:H7. Morphological damage was evident across all bacterial species examined. Physicochemical measurements showed slow decay of the reactive species in the aging process. This study illustrated the potential utility of PAW as an alternative disinfectant.

Evaluation of a novel surface-coating formulation with time-extended antimicrobial activity for healthcare environment disinfection

BackgroundThe importance of environmental contamination in the transmission of pathogens among hospitalized patients is universally recognized, and disinfection of surfaces is a widely accepted modality for reducing healthcare-associated infections. Nevertheless, hospital disinfection is still suboptimal. In this study, we evaluated the sustained effects of the novel formulation OxiLast™ which extends the antimicrobial effects of chlorine-based disinfectants.MethodsIn an experimental lab phase, PVC surfaces were coated with OxiLast™ and then inoculated with representative Gram-positive and Gram-negative pathogenic bacteria. Cells were recovered at different contact times (5, 15, 30 min) to assess the reduction in bacterial counts compared to uncoated surfaces and also subject to various challenges to assess robustness. A similar methodology was then applied in an unoccupied hospital room to evaluate the sustained effect of OxiLast™ on high-touch surfaces.ResultsOxiLast™ demonstrated notable activity against the range of bacterial strains tested with ≥ 4 log10 reduction in bacterial counts observed for up to seven days following one surface application, for various strains and contact times. Similar results were observed following challenges such as simulated abrasion of coated surfaces, organic contamination or successive inoculations. The results were confirmed in a simulated patient care environment.ConclusionsThe addition of OxiLast™ to common chlorine-based disinfectants has shown a substantial and sustained reduction in bacterial pathogen counts for up to 7 days following one application. The consistent results in the laboratory and hospital are promising and should be tested in a real-life clinical scenario.