Bacterial Extracts Research Articles

Ex-vivo antioxidant, enzyme inhibitory properties and computational analysis unveil the molecular mechanism of cardiac and penile phosphodiesterase-5 inhibition by bacterial strain HOKA1 extract as an aphrodisiac's agent

Ex-vivo antioxidant, enzyme inhibitory properties and computational analysis unveil the molecular mechanism of cardiac and penile phosphodiesterase-5 inhibition by bacterial strain HOKA1 extract as an aphrodisiac's agent

Preliminary Assessment of the Protective and Antitumor Effects of Several Phytoene-Containing Bacterial and Microalgal Extracts in Colorectal Cancer.

The identification of new functional food constituents is a priority to improve the prognosis and prevention of colorectal cancer (CRC). In this study, several bacterial and algal phytoene-enriched extracts were obtained, and their potential activity against oxidative damage and their ability to inhibit proliferation and cell migration in several human colon-adenocarcinoma-derived cell lines were assessed. The main conclusions indicate that total extracts of Sphingomonas echinoides and Chlorella sorokiniana exhibited the highest protective effect against oxidative damage. All extracts enhanced the activity of detoxifying enzymes, particularly importantly the increase of NAD(P)H:quinone oxidoreductase activity, which reached a value 40% higher than that of untreated control cells upon exposure to Escherichia coli extracts. Staphylococcus haemolyticus and transgenic E. coli extracts significantly arrested the migration capacity of both cell lines, while S. haemolyticus and C. sorokiniana extracts inhibited cell proliferation by 15 to 20% compared to untreated cells. These results point to these extracts as potential antioxidant complements able to protect cells against oxidative damage and with a moderate ability to inhibit the proliferation and migration of CRC tumor cells, paving the way to design functional foods or probiotic formulations with preventive properties against oxidative stress-related diseases, such as cancer, or as starting point for purifying anticancer compounds.

Synergistic action of bacteriophage and metabolites of Pseudomonas fluorescens JB3B and Streptomyces thermocarboxydus 18PM against Enterotoxigenic Escherichia coli and Bacillus cereus and their biofilm

BackgroundFoodborne disease and food spoilage are the prime public health issue and food security round the globe. Significant disease outbreaks mostly linked to the existence of pathogenic bacteria that extremely challenging due to the persistence of biofilm-forming. Proteins and bacterial metabolites have been shown to have good antibacterial activity and effectively removal bacterial biofilm. Recently, bacteriophage and their encoded lytic proteins such as lysin have attracted attention as potential alternative agent to control undesirable pathogens in human body infection, increasing food safety as advance preservations and medical treatment such as phage therapy. For these reasons, the efficacy of bacteriophage and their potential in combination with bacterial metabolites from Phyllosphere and Actinomycetes bacteria (Pseudomonas fluorescens JB3B and Streptomyces thermocarboxydus 18PM crude extracts) was the aim of this present study.ResultsIn this study, bacteriophage BC-VP (1.28 ± 0.29 × 1011 PFU/ml) and ETEC-phage-TG (8.9 ± 2.19 × 108 PFU/ml) isolated from artificial lake water from previous study showed potential activity to control Bacillus cereus (BC) and Enterotoxigenic Escherichia coli (ETEC) population. The combination of BC-VP with metabolite (P. fluorescens JB3B and S. thermocarboxydus 18PM) which were known from previous study had antibiofilm activities were able to inhibit (86.1%; 83.3%) and destruct (41%; 45.5%) biofilm formation of B. cereus respectively. Likewise, the synergy of bacteriophage ETEC-phage-TG with the same crude extract also showed promising activity against biofilm of ETEC with percentage of inhibition (81.9%; 76.4%) and percentage of destruction (54.1%; 44.4%). Application in various food, combination of BC-VP and bacterial metabolite extract (P. fluorescens JB3B; S. thermocarboxydus 18PM) were able to reduce Bacillus cereus population in mashed potato (99.6%; 99.4%) at cold temperature (4 °C) and (68.9%; 56.6%) at room temperature (28 °C), boiled pasta (99.5%; 99.4%) and (84.7%; 75.7%), also soymilk (96.9%; 96.7%) and (42.4%; 39.4%) respectively. Likewise, combination of ETEC-phage-TG and bacterial metabolite (P. fluorescens JB3B; S. thermocarboxydus 18PM) potentially reduced ETEC population after two different temperatures (4 °C and 28 °C) incubation in bean sprouts (TFTC; TFTC) and (47.5%; 49.1%), chicken meat (TFTC; TFTC) and (58.1%; 54%), also minced beef (99.5%; 99.4%) and (41.1%; 28%). GC-MS determination performed, oxalic acid, phenol, phenylethyl alcohol, N-hexadecanoic acid, and pyrolol[1,2-a]pyrazine-1,4-dione, hexadro-3-92-methylpropyl was the most active compound in P. fluorescens JB3B. 2,4-Di-tert-butylphenol, phenyl acetic acid, N-Hexadecanoic acid, pyrolol[1,2-a]pyrazine-1,4-dione, hexadro-3-92-methylpropyl, and Bis(2-ethylhexyl) phthalate was most active compound in the S. thermocarboxydus 18PM isolates.ConclusionsThe combination of isolated bacteriophages and bacterial metabolite showed promising results to be used as biocontrol candidate to overcome biofilm formed by foodborne and food spoilage bacteria using their ability to produce antibiofilm compounds and lytic activity. In addition, this combination also potentially reduces the use or replace the drawbacks of common application such as antibiotic treatment.

Structural characterization of N-acyl-homoserine lactones from bacterial quorum sensing using LC-MS/MS analyses after Paternò-Büchi derivatization in solution.

Bacterial quorum sensing is a chemical language allowing bacteria to interact through the excretion of molecules called autoinducers, like N-acyl-homoserine lactones (AHLs) produced by Gram-negative Burkholderia and Paraburkholderia bacteria known as opportunistic pathogens. The AHLs differ in their acyl-chain length and may be modified by a 3-oxo or 3-hydroxy substituent, or C = C double bonds at different positions. As the bacterial signal specificity depends on all of these chemical features, their structural characterization is essential to have a better understanding of the population regulation and virulence phenomenon. This study aimed at enabling the localization of the C = C double bond on such specialized metabolites while using significantly lower amounts of biological material. The approach is based on LC-MS/MS analyses of bacterial extracts after in-solution derivatization by a photochemical Paternò-Büchi reaction, leading to the formation of an oxetane ring and subsequently to specific fragmentations when performing MS/MS experiments. The in-solution derivatization of AHLs was optimized on several standards, and then the matrix effect of bacterial extracts on the derivatization was assessed. As a proof of concept, the optimized conditions were applied to a bacterial extract enabling the localization of C = C bonds on unsaturated AHLs.

Screening of Extract Secondary Metabolites of Bacteria Which Have Symbiosis with Sponges from Central Tapanuli Bakar Island as an Antibacteria

This study aims to determine the presence of antibacterial-producing bacteria from sponges from Bakar Island, Central Tapanuli Regency and to determine the antibacterial activity of methanol extracts from potential bacterial isolates against Staphylococcus aureus and Escherichiacoli. 21 pure isolates were found and it was known that 9 isolates produced antibacterial against S. aureus and 4 isolates against E. coli. Bacterial isolates with the highest inhibition zone against bothS.aureus and E. coli were found in isolates with code SP20 with each large inhibition zone are 14.5 mm and 16.04 mm. Then microscopic observations were carried out, namely gram staining and were obtained 8 isolates were gram positive, and 1 gram was negative. The biochemical test showed that SP20 showed positive results for the Motility, TSIA and Catalase Test but negative for Citrate Test. Bacterial isolates withthe code SP20 had the largest inhibition zone so that these isolates were to be extracted.The resultsof the screening test showed that the secondary metabolitesof the sponge symbiont bacterial extract from Bakar Island were positive for flavonoids and saponins. And then test the activity of secondary metabolites with 3 concentrations, 10%, 20%, and 30%.The results showed that the best concentration of the test bacteria was S. aureus at a concentration of 30% with an inhibition zone of 3.08 mm and E. coli at 5.04 mm.

Role of cerium dopant in tuning the semiconductor-to-metal transition properties of magnesium zinc ferrite nanomaterials

In this research work, Magnesium zinc ferrite (CexMgZn1-xFe2O4) nanomaterials have been synthesized with various cerium concentrations (x = 0, 0.05, 0.1, 0.15) using the coprecipitation method. With no deformation as per structural analysis, cerium ions are doped in the spinel lattice of MgZnFe2O4 nanomaterials. The undoped MgZnFe2O4 with initial flake-like morphology is changed to cube-like shapes upon Ce (x = 0.15) addition. The DC resistivity exhibits a varying pattern in both ferromagnetic and paramagnetic regions as temperature increases. Furthermore, the samples with x = 0.15 exhibit a high resistivity on the order of 1.09∗1010 Ω cm, and an activation energy of 0.909 eV. The dielectric properties, such as dielectric constant, dielectric losses, and impedance, exhibit a progressive drop as the frequency increases from 1 MHz to 2 MHz. Furthermore, dielectric parameters reach their lowest value in the dopant x = 0.1. The highest Q values for x = 0.05 and 0.15 indicate that the mentioned materials are most suitable for use in high-frequency devices, likewise multi-layer chip inductors and resonant circuits. Growth inhibition of two types of bacterial extracts (E.Coli and S. aureus) has been studied. Results revealed MgZnFe2O4 enhanced growth inhibition against S. aureus bacteria with increasing Ce concentration, however, inhibition of E. Coli is hampered (50 % at maximum) by Ce incorporation into ferrite lattice.

Enhancing Gingival-Derived Mesenchymal Stem Cell Potential in Tissue Engineering and Regenerative Medicine Through Paraprobiotics.

Gingival-derived mesenchymal stem cells (GMSCs) stand for a unique source of mesenchymal stem cells (MSCs) isolated from a neural crest origin with potential application in regenerative medicine. However, there are some limitations to the usage of these cells in clinical cell therapy such as reduced cell number and undesirable differentiation of the cell throughout frequent passages. Nowadays, studies have applied manipulation strategies to improve MSCs' effectiveness in clinical therapy. Among all of the materials used for this purpose, there is a growing trend for the use of biomaterials such as probiotic extracts or their conditioned media due to their lower toxicity. In the present study, we utilized extracts from Lactobacillus reuteri and Lactobacillus rhamnosus to assess their potential to enhance the function of GMSCs. We compared the effectiveness of these bacterial extracts to determine their relative efficacy. Bacterial extracts of two lactic acid bacteria were prepared using an ultrasonic homogenizing device. The impact of these bacterial extracts on GMSCs was evaluated through Alizarin Red and Oil Red O staining, cell counting by Trypan Blue staining, and real-time polymerase chain reaction. The findings of our study indicate that the administration of 50 μg/mL L. rhamnosus extract resulted in a greater enhancement of stemness marker expression, osteogenic differentiation, and proliferation of GMSCs compared with an equivalent concentration of L. reuteri extract. Neither of these bacterial extracts revealed any effect on the differentiation of the GMSCs into the adipogenic lineage. These findings suggest that L. rhamnosus extract could be more effective at promoting GMSCs' efficacy in tissue engineering and regenerative medicine.

Exploring the antibacterial efficacy of Satureja hortensis and Bacillus subtilis extracts in combating Xanthomonas citri

Biofilm plays a critical role in protecting the associated bacterial colonies. Citrus canker caused by Xanthomonas citri, resulted in remarkable yield reduction in citrus orchards. This study aims to evaluate the anti-biofilm properties of S. hortensis and B. subtilis extracts against X. citri. The antibacterial effects of both extracts were evaluated using the disk diffusion method and 96-well microdilution plates. Crystal violet and XTT procedures were employed to assess the inhibition of adhesion and antibiofilm effects of both extracts. The checkboard titration method was applied to determine the synergistic effects of the plant-bacterial extracts. The antibiofilm effects were confirmed by the light microscopy method. The results showed that the antibacterial and antibiofilm properties of both extracts varied. The MIC values of S. hortensis and B. subtilis extracts were 6.25 and 50 mg/ml, respectively. In these concentrations the inhibition of adhesion effects of S. hortensis and B. subtilis were 70% and 80%, whereas their antibiofilm effects were 60% and 72%. S. hortensis and B. subtilis extracts showed 63% and 76% antibiofilm activity, respectively, using the XTT test. The extracts showed synergistic effects, resulting in higher inhibition rates in combinatorial applications. Molecular docking results also confirmed that the secondary metabolites of S. hortensis could interact with different X. citri proteins differentially. Further large-scale studies on combinatorial antibiofilm effects of plant and bacterial extracts against citrus pathogens will provide new opportunities to develop safe and applicable reagents to control these destructive diseases.

Extraction and characterization of novel alternative cellulosic fiber for sustainable textiles from Aloe barbadensis Miller stems (agricultural waste)

Novel research has been conducted on Aloe vera, focusing on stems fiber (agricultural waste), for the extraction of cellulosic fiber, an area lacking prior scientific exploration. This fiber is being reported for the first time in the scientific community. Aloe barbadensis Miller variety was subjected to various cultivation methods, including the application of inorganic and organic fertilizers, along with the removal of lower leaves to promote stem growth. Stem fibers were extracted using the water retting method and subsequently analyzed. The moisture content was 55.35 % and 6.99 % ash content in the fibers. The bacteriostatic analysis of Aloe vera fibers was assessed against four bacterial strains, with both ethanol and water extracts showing varying degrees of inhibition zones. The UV–Visible spectrum exhibited a distinct λmax at 247 nm in ethanol, while FT-IR analysis provided characteristic peaks at 3759, 1590, 1750, 1663, 1250, 564, SEM images displayed the smooth surface morphology of the fibers, and X-ray diffraction analysis indicated a high degree of crystallinity (78.67 %), suggesting a well-structured and crystalline nature. Energy dispersive X-ray (EDX) analysis was conducted to determine the elemental composition of the fibers, revealing the presence of carbon, oxygen, calcium, and copper, with carbon being the predominant element in cellulose. These results showed promising properties suggesting potential applications in textile industry as an alternative sustainable natural cellulosic fiber.

Reduction of Nitrate and Acrylamide in Heat-processed Meats using treatment with Lactobacillus Casei and Plant Extracts

Background: Food security has always been a concern in the multi-factorial systems analysis of health and wellbeing. The presence of nitrate and acrylamides in cooked meat leads to negative health outcomes. Objective: This study aimed to reduce nitrate and acrylamide content in different kinds of meats (chicken, turkey, lamb, beef, quail, and fish) using some plant extracts and lactobacillus treatment. Methods: The extracts were prepared from Coriandrum sativum, Nigella sativa, and Thymus leaves and stem. The used bacteria was Lactobacillus casei subsp. rhamnosus LCR6013. Acrylamide and nitrate were measured by liquid chromatography and colorimetric spectrophotometry methods Results: The results showed that both bacterial treatment and plant extracts could reduce the amount of acrylamide and nitrate. The most reduction in the amount of acrylamide and nitrate was obtained by adding Thymus and Nigella sativa extracts, followed by coriander extract and bacterial inoculum. Also, bacterial treatment was more effective for nitrate reduction than acrylamide. Conclusion: It was concluded that the plant extracts and bacterial treatment are appropriate solutions to reduce the amount of acrylamide and nitrate during the baking process of meat.

Antibiotic properties of seaweed-associated heterotrophic Bacilli against drug-resistant pathogens

The increasing prevalence in antibiotic resistance has driven the search for novel bioactive compounds in previously unexplored marine habitats. Seaweed-associated symbionts have emerged as significant sources of novel antibacterials against nosocomial pathogens. Herein, eighty-one bacterial isolates were obtained through culture-dependent isolation of seaweed symbionts from the southern coast of India. Bacillus velezensis SK54 represented the largest share (54 %), followed by Bacillus siamensis SK53 (33 %), Bacillus subtilis SK20 (8 %), and Bacillus filamentous SK55 (5 %). B. siamensis SK53 and B. velezensis SK54, which were separated from seaweeds Turbinaria conoides and Dictyota cervicornis, respectively, demonstrated clearance zones over 25 mm on spot-over-lawn assay against multiple clinical pathogens, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Staphylococcus aureus (VRSA). Selected isolates were sensitive to commercially available antibiotics, and no pathogenicity was observed. The isolates did not amplify pore-forming non-haemolytic haemolysin BL (hbl) and enterotoxin (nhe) genes, and haemolysis on blood agar confirmed their non-pathogenic nature. The bacterial extracts exhibited significant antibacterial activity against the tested pathogens, including MRSA and VRSA, with a minimum inhibitory concentration (MIC) range of 6.25–12.5 μg/mL. The 700 bp type-I polyketide synthase (pks) genes (OQ657454, OQ706631, OQ737799, and OQ834957) were amplified from the heterotrophic B. siamensis SK53 and B. velezensis SK54, with a 99 % identity in the BLAST search. The substantial antibacterial potential against drug-resistant bacteria, along with the presence of genes encoding bioactive lead molecules, suggests that these marine symbiotic bacteria, B. siamensis SK53 and B. velezensis SK54, could be effective in combating emerging antibiotic resistance.

The Biological Effect of Synthesized Zinc Oxide Nanoparticles on Organic Pollutions in Drinking Water

This study aimed to demonstrate the biosynthesis procedure of zinc oxide nanoparticles (Zn-O NPs) by using extracellular components from environmental isolates of Escherichia coli as reducing and stabilizing agent by adding 1 g of zinc sulfate to 10 ml of bacterial extract to prepare of zinc oxide nanoparticles. These organic pollutants are considered one of the most important causes of poisoning that have great health risks to humans and are also considered one of the most dangerous environmental pollutants as they are toxic and harmful to the environment. The optimum condition for Zn-O biosynthesis was characterized through several devices and techniques such as ultraviolet- visible (UV-Vis) Atomic force microscope (AFM) X-Ray diffractometer (XRD) Fourier Transform Infrared spectroscopy (FTIR) and field emission scanning electron microscopy (FE-SEM). In particular, a cutoff phenomenon of the biological synthesized Zn-O was found at around 325 nm using UV-Vis, while spherical shape particles were noticed using FE-SEM techniques. Also, the results of the AFM analysis revealed that Zn-O NPs have an average diameter of 37.15 nm. Determining the FTIR spectrum of the biosynthesized Zn-O nanoparticles showed Zn-O at the broad peak at 694.33 cm.

Nanodisc assembly from bacterial total lipid extracts

Nanodiscs are discoidal lipoproteins that have often been used as vehicles to study membrane proteins in their native configuration. Nanodiscs have been primarily made from synthetic lipids. However, nanodiscs also offer a format by which native lipids can be studied in their natural configuration. Here, we present a method to synthesize nanodiscs from bacterial total lipid extracts using the biothreat agent, Yersinia pestis, as a proof-of-concept. The creation of nanoparticles entirely composed of bacterial lipids supports membrane characterization and vaccine antigen discovery without the inherent safety concerns associated with live bacterial cells of this Tier 1 select agent pathogen.

Neuroprotective Effects Exerted by a Combination of Selected Lactic Acid Bacteria in a Mouse Parkinsonism Model under Levodopa-Benserazide Treatment.

Alterations of the microbiota-gut-brain axis has been associated with intestinal and neuronal inflammation in Parkinson's disease (PD). The aim of this work was to study some mechanisms associated with the neuroprotective effect of a combination (MIX) of lactic acid bacteria (LAB) composed by Lactiplantibacillus plantarum CRL2130 (riboflavin overproducing strain), Streptococcus thermophilus CRL808 (folate producer strain), and CRL807 (immunomodulatory strain) in cell cultures and in a chronic model of parkinsonism induced with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in aged mice, and under levodopa-benserazide treatment. In vitro, N2a differentiated neurons were exposed to the neurotoxin 1-methyl-4-phenylpyridinium (MPP+) and treated with intracellular bacterial extracts or with conditioned media from BV-2 cells exposed to the bacterial extracts. In vivo, motor skills, tyrosine hydrolase (TH) in brain and cytokine concentrations in serum and in brain were evaluated. The study of the faecal microbiota and the histology of the small intestine was also performed. The results showed that the neuroprotective effect associated with LAB MIX administration did not interfere with levodopa-benserazide treatment. This effect could be associated with the antioxidant and immunomodulatory potential of the LAB selected in the MIX, and was associated with the significant improvement in the motor tests and a higher number of TH + cells in the brain. In addition, LAB MIX administration was associated with modulation of the immune response. LAB administration decreased intestinal damage with an increase in the villus length /crypt depth ratio. Finally, the administration of the LAB MIX in combination with levodopa-benserazide treatment was able to partially revert the intestinal dysbiosis observed in the model, showing greater similarity to the profiles of healthy controls, and highlighting the increase in the Lactobacillaceae family. Different mechanisms of action would be related to the protective effect of the selected LAB combination which has the potential to be evaluated as an adjuvant for conventional PD therapies.

LARVICIDAL EFFICACY OF ALCOHOL-BASED EXTRACTION OF VERNONIA AMYGDALINA WITH BACILLUS THURINGIENSIS ON THE VECTOR AEDES AEGYPTI

Mosquitoes are the most significant category of hematophagous arthropods. Traditional medicine uses numerous plants for their larvicidal properties against mosquitoes in various regions globally. The combination of bacterial toxin and plant extract has a significant impact on mosquito larvae. We evaluated the larvicidal effectiveness of the plant extract Vernonia amygdalina in combination with B. thuringiensis against third instar larvae of Aedes aegypti. We recorded the average mortality and percentage mortality of larval populations at various concentrations after 24 and 48 hours of exposure. Bti and Vernonia amygdalina extracts showed significant insecticidal efficacy, as evidenced by LC 50 and LC 90 values. The LC50 values for 24-hour and 48-hour exposure are 18.35 and 16.71, respectively. The LC 90 values at 24 hours and 48 hours of exposure are 32.47 and 29.39, respectively.

Investigation of Biofilm Formation, Anti-Quorum Sensing Activity and Antimicrobial Resistance in Corynebacterium Species Isolated from Clinical Samples

An increasing number of different clinical infections caused by Corynebacteria have been reported in the last decade. The aim of this study was to evaluate the antibiotic resistance rates, biofilm formation capacities and to investigate the ''anti-quorum-sensing (anti-QS)'' activities of corynebacteria, which were divided into three groups according to the type of growth in culture (pure, with another pathogenic bacterium and polymicrobial growth). In total 240 Corynebacterium spp. isolates from different clinical specimens sent to the medical microbiology laboratories of Düzce University Faculty of Medicine Hospital and Başakşehir Çam and Sakura City Hospital between June 2021 and June 2022 were classified into three groups: pure, isolated with another pathogen and polymicrobial, according to their growth patterns in culture. Bacteria were identified by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) Biotyper (Bruker, Germany) at an external centre. Antibiotic susceptibilities were determined by disc diffusion method and for vancomycin broth microdilution method was used. Results were interpreted according to EUCAST recommendations. The biofilm-forming properties of the isolates were determined quantitatively. Bioactive components of 17 isolates with strong biofilm formation were extracted and anti-QS activity was determined by agar diffusion method using Chromobacterium violaceum ATCC 12472 strain and then violacein pigment production was measured quantitatively. Of the 240 Corynebacterium spp. isolates, 138 (58%) were pure, 52 (22%) were isolated with another pathogen and 50 (20%) were part of a polymicrobial infection. Of the isolates, 140 were identified as C.striatum, 34 as C.amycolatum and 24 as Corynebacterium afermentans. When the antibiotic resistance rates of the Corynebacterium isolates were analysed according to the groups, the resistance rates to rifampicin and tetracycline antibiotics were found to be statistically significantly lower in the polymicrobial group than in the other groups. The resistance rates to penicillin, clindamycin, ciprofloxacin, moxifloxacin, rifampicin, tetracycline and linezolid were 96.7%, 88.3%, 86.3%, 73.8%, 62.5%, 59.2% and 0.8%, respectively. While all isolates were susceptible to vancomycin, linezolid resistance was detected in two C.afermentans isolates. When the biofilm formation ability was analysed, it was observed that 87 (36.3%) isolates formed biofilm. The biofilm formation rate of the isolates in the polymicrobial growth group was lower than the other two groups. The anti-QS activity of 17 isolates with strong biofilm formation was investigated and none of the Corynebacterium extracts tested were found to have anti-QS activity (inhibition of violacein pigment production without inhibiting bacterial growth) in the QS study with C.violaceum, whereas five isolate extracts had antibacterial activity (inhibition of bacterial growth). Four of the bacterial extracts with antimicrobial activity belonged to C.amycolatum and one to C.afermentans. In conclusion, when both antibiotic resistance rates and biofilm formation rates were analysed, the corynebacteria growing in culture with another pathogen showed similar characteristics to the corynebacteria growing as a pure culture. Therefore, it was thought that corynebacteria growing with another pathogen should not be ignored. In addition, the antimicrobial effects of some corynebacterial extracts suggested that more QS studies should be carried out with microbiota bacteria.

Comparison of DeNovix, NanoDrop and Qubit for DNA quantification and impurity detection of bacterial DNA extracts.

Accurate DNA quantification is key for downstream application including library preparations for whole genome sequencing (WGS) and the quantification of standards for quantitative PCR. Two commonly used technologies for nucleic acid quantification are based on spectrometry, such as NanoDrop, and fluorometry, such as Qubit. The DS-11+ Series spectrophotometer/fluorometer (DeNovix) is a UV spectrophotometry-based instrument and is a relatively new spectrophotometric method but has not yet been compared to established platforms. Here, we compared three DNA quantification platforms, including two UV spectrophotometry-based techniques (DeNovix and NanoDrop) and one fluorometry-based approach (Qubit). We used genomic prokaryotic DNA extracted from Streptococcus pneumoniae using a Roche DNA extraction kit. We also evaluated purity assessment and effect of a single freeze-thaw cycle. Spectrophotometry-based methods reported 3 to 4-fold higher mean DNA concentrations compared to Qubit, both before and after freezing. The ratio of DNA concentrations assessed by spectrophotometry on the one hand, and Qubit on the other hand, was function of the A260/280. In case DNA was pure (A260/280 between 1.7 and 2.0), the ratio DeNovix or Nanodrop vs. Qubit was close or equal to 2, while this ratio showed an incline for DNA with increasing A260/280 values > 2.0. The A260/280 and A260/230 purity ratios exhibited negligible variation across spectrophotometric methods and freezing conditions. The comparison of DNA concentrations from before and after freezing revealed no statistically significant disparities for each technique. DeNovix exhibited the highest Spearman correlation coefficient (0.999), followed by NanoDrop (0.81), and Qubit (0.77). In summary, there is no difference between DeNovix and NanoDrop in estimated gDNA concentrations of S. pneumoniae, and the spectrophotometry methods estimated close or equal to 2 times higher concentrations compared to Qubit for pure DNA.

Cytotoxic and apoptosis-inducing properties of Staphylococcus aureus cytoplasmic extract on lung cancer cells: Insights from MTT assay and bax/bcl-2 gene expression analysis

BackgroundLung cancer ranks as the second most prevalent cancer in both men and women and stands as one of the most prevalent and lethal malignancies globally. In recent decades, the therapeutic potential of bacteria has gained recognition in pharmaceutical and therapeutic research. While bacteria have historically been associated with cancer causation, recent studies have unveiled their potential as efficacious agents for targeted cancer therapy. However, limited data exist on the characterization and impact of Staphylococcus aureus (S. aureus) extract on lung cancer cell lines. Consequently, this study aims to investigate the effect of S. aureus extract on inducing apoptosis in A549, a lung cancer cell line, and MRC-5, a lung normal cell line, by evaluating the expression levels of the bax and bcl-2 genes. MethodsInitially, cytoplasmic extract of S. aureus was prepared using the sonication technique. The protein concentration was determined via the Bradford assay, and the presence of proteins was confirmed using SDS-PAGE. A549, representing a lung cancer cell line, and MRC-5, representing a lung normal cell line, were exposed to varying concentrations of bacterial extract, and cell viability was assessed using the MTT assay. Subsequently, the expression levels of the bax and bcl-2 genes were quantified utilizing the Real-Time PCR method. ResultsCytoplasmic extract derived from S. aureus demonstrated the ability to modulate the expression levels of apoptotic genes. Relative to the control group, the bax gene exhibited a fivefold overexpression, while the expression of the bcl-2 gene decreased by more than half compared to the control. Furthermore, the results of the MTT assay indicated that the bacterial cytoplasmic extract exhibited concentration-dependent cytotoxicity on cancer cells, highlighting a significant increase in cell death with escalating concentrations. ConclusionsThis research highlights the potential of S. aureus extract for targeted lung cancer therapy by promoting cancer cell apoptosis while sparing normal cells. These findings open up exciting possibilities for innovative cancer treatments and improved patient outcomes, emphasizing the promise of S. aureus extract in the fight against lung cancer.

Antifouling activity of marine bacterial extracts: A non-toxic alternative as biocide

Antifouling activity of marine bacterial extracts: A non-toxic alternative as biocide

Pomegranate Rhizosphere Microbial Diversity Revealed by Metagenomics: Toward Organic Farming, Plant Growth Promotion and Biocontrol?

Food production must undergo systems change to meet the sustainable development goals (SDGs). For example, organic farming can be empowered by soil microorganisms with plant growth promotion (PGP) and biocontrol features. In this context, there have been limited studies on pomegranate. We investigated microbial diversity in rhizosphere of the pomegranate "Bhagwa" variety and its potential role in PGP and biocontrol. Both bulk and rhizosphere soil samples were analyzed for their physicochemical properties. Whole metagenome sequencing was conducted using the Illumina NovaSeq6000 platform. Surprisingly, we found that bulk and rhizosphere soil samples had comparable microbial diversity. Metagenome sequencing revealed the abundance of Streptomyces indicus, Bradyrhizobium kalamazoonesis, and Pseudomonas cellulosum in the rhizosphere that are reported here for the first time in agricultural literature. Pathway prediction analysis using KEGG (Kyoto Encyclopedia for Genes and Genomes) and COG (clusters of orthologous genes) databases identified metabolic pathways associated with biocontrol properties against pathogens. We confirmed the metagenome data in vitro, which demonstrated their PGP potential and antimicrobial properties. For instance, S. indicus produced high concentration of indole-3-acetic acid, a PGP phytohormone, that can stimulate plant growth. In addition, an antimicrobial susceptibility assay suggested that bacterial extracts displayed activity against Xanthomonas, a primary pathogen causing the pomegranate wilt disease. In conclusion, this study suggests that S. indicus, B. kalamazoonesis, and P. cellulosum can potentially be PGP and biocontrol agents that may contribute to increased crop productivity in pomegranate cultivation. These agents and their combinations warrant future research with an eye on SDGs and so as to enable and innovate organic farming and pomegranate agricultural practices.