Antibacterial Assay Research Articles

In Vitro Biological and GC-MS Analysis of Whole Plant Calotropis procera

Calotropis procera is a medicinal, traditional, and therapeutic plant in Pakistan. In this research study, the biological activities, for instance, anticancer, antileishmanial, antibacterial, antifungal, anti-inflammatory, and brine shrimp lethality assay and GC-MS are studied. MTT assay, antileishmanial bioassay, microplate Alamar Blue assay, agar tube dilution method, oxidative burst assay using chemiluminescence technique, B-hatching techniques, and triple quadrupole acquisition method MS parameters were the methods used for anticancer, antileishmanial, antibacterial, antifungal, anti-inflammatory, brine shrimp lethality assay, and gas chromatography-mass spectrometry. Whole plant methanol extract of Calotropis procera (WMECP) inhibited 69.1% of the growth of HeLa cell line with an IC50 value of 3.1 ± 0.4 and whole plant n-hexane fraction of Calotropis procera (WHFCP) and whole plant and aqueous fraction of Calotropis procera (WAFCP) inhibited the growth by 70.2% and 65.2% with IC50 values of 5.0 ± 0.3 and 17.1 ± 1.0. Whole plant methanol extract of Calotropis procera (WMECP) inhibited 70.1% of the growth of the PC3 cell line with an IC50 value of 5.1 ± 0.3 and whole plant n-hexane fraction of Calotropis procera (WHFCP) and whole plant aqueous fraction of Calotropis procera (WAFCP) inhibited 61.6% and 59.7% with IC50 values of 3.7 ± 0.5 and 16.4 ± 1.0. None of the extract and fractions of Calotropis procera showed anticancer activities against the 3T3 cell line. None of the extract and fractions of Calotropis procera showed antileishmanial, antibacterial, antifungal, and anti-inflammatory activities. Whole plant methanol extract of Calotropis procera (WMECP) exhibited lethality at the highest concentration while other fractions did not exhibit lethality. GC-MS studies revealed that the whole plant methanol extract of Calotropis procera (WMECP) consists of 11 compounds, whole plant n-hexane fraction of Calotropis procera (WHFCP) consists of 9 compounds, and whole plant aqueous fraction of Calotropis procera (WAFCP) consists of 7 compounds.

Hybrid structured silk-rPET nanotechnical cloth for advanced air purification

AbstractAir pollution has become a significant global issue due to its detrimental environmental and human health effects. In this study, a novel approach was taken to address these challenges by developing a recycled polyethylene terephthalate (rPET) nano-coated silk technical cloth embedded with green-synthesized silver nanoparticles (AgNPs) using a solution electrospinning technique. The filtration performance of the developed material was assessed through particle filtration efficiency (PFE) tests, while differential pressure (DP) tests were conducted to evaluate pressure drop. SEM, FTIR, tensile, antibacterial, radiative heat barrier performance, and moisture management properties of the developed samples were also performed. Maximum 96.58% of filtration performance was observed with corresponding low differential pressures of 29.1 Pa/cm2; maximum tensile force and elongation% were 157.47 N and 15.32%, respectively of the developed samples. FTIR analysis confirmed the presence of silk, rPET, sodium alginate, and AgNPs in the developed sample. Antibacterial assays demonstrated inhibition against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Moisture management property revealed water penetration resistance and radiative heat barrier testing showed good barrier performance. These results make the promising potential of the developed material as an advanced air filter. Graphical Abstract

Polydopamine reduced graphene oxide/ chitosan-based hydrogel for the therapy of diabetic wound

Diabetic foot ulcer (DFU) is a serious complication of diabetes, often leading to high risks of amputation and imposing considerable economic burdens on patients. Hyperglycemia induced impaired angiogenesis and increased susceptibility to bacterial infection are common obstacles in DFU wound healing, which impede the recovery process. In this work, a novel multifunctional polydopamine reduced graphene oxide chelating copper ions chitosan (PDA-rGO@Cu/CS) hydrogel was developed. Specifically, PDA-rGO@Cu/CS hydrogel dressing was facilitated efficient sterilization and angiogenesis, which attributed to the remarkable photothermal performance and the catalyzing NO release function of hydrogel. Experimental results indicated that the hydrogel accelerated the wound healing process in diabetic rats after topical application and the wound closure rate reached up to 91.57% (vs. 60% of the control) on day 14. Furthermore, in vitro/vivo antibacterial assays demonstrated that the hydrogel possessed antibacterial activity against E.coli and S.aureus, and improved infected wound healing as well as wound closure, which reached up to 90.42% on day 10. Mechanistically, H&E staining, Masson staining, immunofluorescent staining for CD31&α-SMA and IL-6 exhibited that the hydrogel accelerated full-thickness skin wound reconstruction by inhibiting inflammation, promoting collagen deposition and accelerating angiogenesis. Collectively, PDA-rGO@Cu/CS hydrogel provided a promising and efficient treatment strategy for DFU.

Polysilsesquioxane decorated ZIF-8 as a potential pH-responsive vehicle for topical delivery and release of acyclovir and tetracycline: Investigation of blood compatibility, cytotoxicity and antibacterial properties

In this research, poly-chloropropylmethyl-silsesquioxanen was prepared and decorated with ZIF-8 in order to investigate its loading capacity for acyclovir and tetracycline. Before and after drug loadings, the composites were characterized by FT-IR, SEM-EDS, XRD, and XPS analyses. Then, the in-vitro release of these drugs was investigated by UV–Vis spectroscopy in different buffers (pH = 5, 7.4, and 9.1). The results showed that the release of ACV reached a maximum amount of 41.3 mg at pH = 7.4 during 12 h. In comparison, the release of TC reached a maximum amount of 22.5 mg at pH = 5 during 6 h. The blood compatibility, in-vitro cytotoxicity on the L929 fibroblast cells line, and antibacterial assay against Staphylococcus aureus and Pseudomonas aeruginosa were also investigated for this composite as a drug carrier.

Phytochemical Analysis, Antioxidant Potential and Antibacterial Activities of Different Anatomical Parts of Hypericum cordifolium Choisy.

The genus Hypericum comprises a large number of species. The flower, leaf, stem, and root of the Hypericum species are widely used in traditional medicine in different cultures. Many Hypericum species have been well investigated phytochemically and pharmacologically. However, only a few reports are available on the H. cordifolium native to Nepal. The present study aims to evaluate the phytochemical composition of different extracts, qualitative analysis of methanol extract of the flower and leaf using thin-layer chromatography (TLC), and the antioxidant properties of components by the TLC-DPPH. assay. The phenolic and flavonoid contents were estimated in different extracts of the leaf and stem, and their antioxidant and antibacterial activities were evaluated. In the phytochemical screening, phenolics and flavonoids were present in ethyl acetate, methanol, and 50% aq methanol extracts of both the leaf and stem. In TLC analysis, the methanol extract of flowers showed the presence of 11 compounds and the leaf extract showed the presence of 8 compounds. Both extracts contained chlorogenic acid and mangiferin. Hyperoside and quercetin were present only in the flower extract. In the TLC-DPPH. assay, almost all of the flower extracts and 5 compounds of the leaf extract showed radical scavenging potential. Estimation of phenolics and flavonoids showed that all the leaf extracts showed higher amounts of phenolics and flavonoids than stem extracts. Among leaf extracts, greater amounts of phenolics were detected in 50% aqueous methanol extract (261.25 ± 1.66 GAE/g extract) and greater amounts of flavonoids were detected in methanol extract (232.60 ± 10.52 CE/g extract). Among stem extracts, greater amounts of flavonoids were detected in the methanol extract (155.12 ± 4.30 CE/g extract). In the DPPH radical scavenging assay, the methanol extract of the leaf showed IC50 60.85 ± 2.67 µg/ml and 50% aq. methanol extract of the leaf showed IC50 63.09 ± 2.98 µg/ml. The methanol extract of the stem showed IC50 89.39 ± 3.23 µg/ml, whereas ethyl acetate and 50% aq. methanol extract showed IC50 > 100 µg/ml. In the antibacterial assay, the methanol extract of the leaf showed the inhibition zone of 12-13 mm and the stem extract showed the inhibition zone of 7-11 mm against S. aureus, E. coli, and S. sonnei, whereas both extracts were inactive against S. typhi. The findings of this study support the traditional use of this plant in Nepal for the treatment of diseases associated with bacterial infections. The present study revealed that the underutilized anatomical parts of H. cordifolium could be the source of various bioactive phytochemicals like other Hypericum species.

Visible-Light-Responsive Novel Ru(II)-Metallo-Antibiotics with Potential Antibiofilm and Antibacterial Activity.

Growing challenges with antibiotic resistance pose immense challenges in combating microbial infections and biofilm prevention on medical devices. Lately, antibacterial photodynamic therapy (aPDT) is now emerging as an alternative therapy to overcome this problem. Herein, we synthesized and characterized four Ru(II)-complexes, viz., [Ru(ph-tpy)(bpy)Cl]PF6 (Ru1), [Ru(ph-tpy)(dpq)Cl]PF6 (Ru2), [Ru(ph-tpy)(dppz)Cl]PF6 (Ru3), and [Ru(ph-tpy)(dppn)Cl]PF6 (Ru4) (where 4'-phenyl-2,2':6',2″-terpyridine = ph-tpy; 2,2'-bipyridine = bpy; dipyrido[3,2-f:2',3'-h]quinoxaline = dpq; dipyrido[3,2-a:2',3'-c]phenazine = dppz; and Benzo[I]dipyrido[3,2-a:2',3'-c]phenazine = dppn), among which Ru2-Ru4 are novel. Octahedral geometry of the complexes with a RuN5Cl core was evident from the crystal structure of Ru2. Ru1-Ru4 showed an MLCT absorption band in the 450-600 nm region, useful for aPDT performances. Further, optimum triplet excited state energy and excellent photostability of Ru1-Ru4 made them good photosensitizers for aPDT. Ru1-Ru4 demonstrated enhanced antimicrobial activity on visible-light exposure (400-700 nm, 10 J cm-2), confirmed using different antibacterial assays. Mechanistic studies revealed that inhibition of bacterial growth was due to the generation of oxidative stress (via NADH oxidation and ROS generation) upon treatment with Ru2-Ru4, resulting in destruction of the bacterial wall. Ru2 performed best killing performance against both Gram-negative (Escherichia coli) and Gram-positive (Bacillus subtilis) bacteria when exposed to light. Ru2-Ru4, when coated on a polydimethylsiloxane (PDMS) disk, showed long-term reusability and durable antibiofilm properties. Molecular docking confirmed the efficient interaction of Ru2-Ru4 with FabH (regulates fatty acid biosynthesis of E. coli) and PgaB (gives structural stability and helps biofilm formation of E. coli), resulting in probable downregulation. In vivo studies with healthy Wistar rats confirmed the biocompatibility of Ru2. This study shows that these lead complexes (Ru2-Ru4) can be used as potent alternative antimicrobial agents in low concentrations toward bacterial eradication with photodynamic therapy (PDT).

Isolation of Novel 6-methylideneoxecane-3,4,5,7,8,9-hexol from the Leaves of Rauwolfia vomitoria, Apocynaceae

Rauwolfia vomitoria (Wennberg) belongs to the family Apocynaceae, the dried leaves were extracted successively using n-hexane, dichloromethane, and 70% methanol, concentrated in vacuo. Extracts were subjected to antibacterial assay and the butanol fraction was subjected to chromatographic purification to obtain NBF12 which was subjected to spectral analysis. The antibacterial of n-Hexane, dichloromethane, and 70% methanol extracts was inactive against the screened organisms assessed (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa). NBF12 is yellowish crystals (10.5 mg), Rf (0.69), UV, max Abs (248) The carbon 13C-NMR spectrum displayed ten carbon atoms; one methylene, two methylene oxide carbon, 6-carbinolic carbon (Sp3) and a quaternary carbon (SP2). The spectrum showed a tertiary carbon at δ131.09 ppm, due to C-6 and at δ 114.74 ppm due to exocyclic methylidene carbon (Sp2) (C=CH2) linked to the C-6position. Based on the spectral data NBF12 is 6-methylideneoxecane-3,4,5,7,8,9-hexol with a molecular formula C10H18O7, molecular weight 250 g/mol.

Exploring the Antibacterial Potential of Artemisia judaica Compounds Targeting the Hydrolase/Antibiotic Protein in Klebsiella pneumoniae: In Vitro and In Silico Investigations.

Carbapenem antibiotic resistance is an emerging medical concern. Bacteria that possess the Klebsiella pneumoniae carbapenemase (KPC) protein, an enzyme that catalyzes the degradation of carbapenem antibiotics, have exhibited remarkable resistance to traditional and even modern therapeutic approaches. This study aimed to identify potential natural drug candidates sourced from the leaves of Artemisia judaica (A. judaica). The phytoconstituents present in A. judaica dried leaves were extracted using ethanol 80%. A reasonable amount of the extract was used to identify these phytochemicals via gas chromatography/mass spectrometry (GC/MS). One hundred twenty-two bioactive compounds from A. judaica were identified and subjected to docking analysis against the target bacterial protein. Four compounds (PubChem CID: 6917974, 159099, 628694, and 482788) were selected based on favorable docking scores (-9, -7.8, -7.7, and -7.5 kcal/mol). This computational investigation highlights the potential of these four compounds as promising antibacterial candidates against the specific KPC protein. Additionally, in vitro antibacterial assays using A. judaica extracts were conducted. The minimum inhibitory concentration (MIC) against the bacterium K. pneumonia was 125 μg/mL. Well-disk diffusion tests exhibited inhibition zones ranging from 10.3 ± 0.5 mm to 17 ± 0.5 mm at different concentrations, and time-kill kinetics at 12 h indicated effective inhibition of bacterial growth by A. judaica leaf extracts. Our findings have revealed the pharmaceutical potential of Artemisia judaica as a natural source for drug candidates against carbapenem-resistant pathogens.

Coordination-Driven Self-Assembly of Metal Ion-Antisense Oligonucleotide Nanohybrids for Chronic Bacterial Infection Therapy.

Bacterial infection poses a significant challenge to wound healing and skin regeneration, leading to substantial economic burdens on patients and society. Therefore, it is crucial to promptly explore and develop effective methodologies for bacterial infections. Herein, we propose a novel approach for synthesizing nanostructures based on antisense oligonucleotides (ASOs) through the coordination-driven self-assembly of Zn2+ with ASO molecules. This approach aims to provide effective synergistic therapy for chronic wound infections caused by Staphylococcus aureus (S. aureus). The resulting hybrid nanoparticles successfully preserve the structural integrity and biological functionalities of ASOs, demonstrating excellent ASO encapsulation efficiency and bioaccessibility. In vitro antibacterial experiments reveal that Zn-ASO NPs exhibit antimicrobial properties against Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. This antibacterial ability is attributed to the high concentration of metal zinc ions and the generation of high levels of reactive oxygen species. Additionally, the ftsZ-ASO effectively inhibits the expression of the ftsZ gene, further enhancing the antimicrobial effect. In vivo antibacterial assays demonstrate that the Zn-ASO NPs promote optimal skin wound healing and exhibit favorable biocompatibility against S. aureus infections, resulting in a residual infected area of less than 8%. This combined antibacterial strategy, which integrates antisense gene therapy and metal-coordination-directed self-assembly, not only achieves synergistic and augmented antibacterial outcomes but also expands the horizons of ASO coordination chemistry. Moreover, it addresses the gap in the antimicrobial application of metal-coordination ASO self-assembly, thereby advancing the field of ASO-based therapeutic approaches.

Preliminary Purification and Partial Characterization of a Functional Bacteriocin of Lacticaseibacillus paracasei Zhang and Mining for its Gene Cluster.

Bacteriocins produced by lactic acid bacteria (LAB) have good potential for use as food biopreservatives. Lacticaseibacillus paracasei Zhang (L. paracasei Zhang) is both a food use and a probiotic bacterium. This study aimed to purify and preliminary characterize the active antibacterial metabolite of L. paracasei Zhang. The cell-free supernatant of L. paracasei Zhang was collected and purified by ultrafiltration and gel filtration chromatography. The 1-3kDa active fraction could inhibit the growth of Staphylococcus aureus but not Escherichia coli. Further antibacterial activity assays revealed its capacity to suppress various foodborne and human opportunistic pathogens (including Staphylococcus aureus, Pseudomonas fluorescens, Pseudomonas aeruginosa, Listeria monocytogenes, and Bacillus cereus), but not fungi. The antibacterial activity showed good tolerance to heat (40 to 100°C), acid-base (pH 2-3 and pH 6-10), and digestions by a number of industrial and animal/human enzymes (such as trypsin, pepsin, α-amylase, and protease K, except papain); these desired properties make it a suitable biopreservative to be used in harsh and complex industrial production processes. The high papain sensitivity suggested a proteinaceous/peptide nature of the bioactivity. Moreover, our genomic data mining for bacteriocin through BAGEL4 revealed an area of interest encoding a complete set of putative genes required for bacteriocin production. In conclusion, our study showed that L. paracasei Zhang can produce extracellular functional antibacterial metabolite, likely a class II bacteriocin. Our preliminary extraction and characterization of the active metabolite demonstrated that it has good potential to be used as a biopreservative or an agent for suppressing gastrointestinal infections.

Biosynthesized silver nanoparticles prevent bacterial infection in chicken egg model and mitigate biofilm formation on medical catheters.

Investigating the application of innovative antimicrobial surface coatings on medical devices is an important field of research. Many of these coatings have significant drawbacks, including biocompatibility, coating stability and the inability to effectively combat multiple drug-resistant bacteria. In this research, we developed an antibiofilm surface coating for medical catheters using biosynthesized silver nanoparticles (b-Cs-AgNPs) developed using leaves extract of Calliandra surinamensis. Various characterization techniques were employed to thoroughly characterize the synthesized b-Cs-AgNPs and c-AgNPs. b-Cs-AgNPs were compatible with human normal kidney cells and chicken embryos. It did not trigger any skin inflammatory response in in vivo rat model. b-Cs-AgNPs demonstrated potent zone of inhibition of 19.09mm when subjected to the disc diffusion method in E. coli confirming strong antibacterial property. Different anti-bacterial assays including liquid growth curve, colony counting assay, biofilm formation assay supported the potent antimicrobial efficacy of b-Cs-AgNPs alone and when coated to medical grade catheters. Mechanistic studies reveal the presence of ferulic acid, that was important for the synthesis of b-AgNPs along with enhanced antibacterial effects of b-Cs-AgNPs compared to c-AgNPs, supported by molecular docking analysis. These results together demonstrated the effective role b-Cs-AgNPs in combating infections and mitigating biofilm formations, highlighting their need for further study in the field of biomedical applications.

3D-printed polyether-ether ketone/carboxymethyl cellulose scaffolds coated with Zn–Mn doped mesoporous bioactive glass nanoparticles

Patient-specific fabrication of scaffold/implant requires an engineering approach to manufacture the ideal scaffold. Herein, we design and 3D print scaffolds comprised of polyether-ether-ketone (PEEK) and sodium-carboxymethyl cellulose (Na-CMC). The fabricated scaffold was dip coated with Zn and Mn doped bioactive glass nanoparticles (Zn–Mn MBGNs). The synthesized ink exhibit suitable shear-thinning behavior for direct ink write (DIW) 3D printing. The scaffolds were crafted with precision, featuring 85% porosity, 0.3 mm layer height, and 1.5 mm/s printing speed at room temperature. Scanning electron microscopy images reveal a well-defined scaffold with an average pore size of 600 ± 30 μm. The energy dispersive X-ray spectroscopy analysis confirmed a well dispersed/uniform coating of Zn–Mn MBGNs on the PEEK/Na-CMC scaffold. Fourier transform infrared spectroscopy approved the presence of PEEK, CMC, and Zn–Mn MBGNs. The tensile test revealed a Young's modulus of 2.05 GPa. Antibacterial assays demonstrate inhibition zone against Staphylococcus aureus and Escherichia Coli strains. Chick Chorioallantoic Membrane assays also present significant angiogenesis potential, owing to the antigenic nature of Zn–Mn MBGNs. WST-8 cell viability assays depicted cell proliferation, with a 103% viability after 7 days of culture. This study suggests that the PEEK/Na-CMC scaffolds coated with Zn–Mn MBGNs are an excellent candidate for osteoporotic fracture treatment. Thus, the fabricated scaffold can offer multifaceted properties for enhanced patient outcomes in the bone tissue regeneration.

Mitigation of oxidative stress and inflammatory factors, along with the antibrowning and antimicrobial effects of cassia seed microbial fermentation solution.

Cassia seeds, originating from the mature seeds of leguminous cassia species, possess pharmacological effects attributed to their rich composition of various active ingredients, notably anthraquinones. While current research predominantly focuses on pharmaceutical extractions, there has been limited progress in fermentation studies. Our study aimed to enhance the content of active compounds such as anthraquinones, flavonoids, and polyphenols using microbial fermentation techniques. We specifically optimized a fermentation system through a single-factor experimental design. The antioxidant properties of the fermentation solution were validated through assays involving HaCaT cells and zebrafish. We observed effective suppression of inflammatory reactions in both RAW264.7 cells and transgenic zebrafish by the fermentation solution. Moreover, significant inhibition of tyrosinase activity and melanin production was evident in B16-F10 cells and zebrafish. Positive outcomes were also obtained in antibacterial assays and chick embryo experiments. These findings highlight the potential of cassia seed fermentation solution as a safe and eco-friendly material in food chemistry and biomedical sciences.

In-vitro assessment of biocompatibility and antimicrobial properties of 85S bio-glass and SrTiO3 composites

Strontium-containing ceramics enhance bone healing and graft osseointegration, but bacterial infections may impede the process, risking surgical failure. In this study, we explore the development of composites comprising strontium titanate (SrTiO3) and 85S (85SiO2–10CaO–5P2O5 mol%) bio-glass at varying concentrations using in-vitro tests such as simulated body fluid (SBF), MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide), hemolysis, and antibacterial assays. X-ray diffractogram (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) analyses confirm the development of the hydroxyapatite layer after immersing in SBF. Notably, 10 wt% of SrTiO3 in 85S bio-glass (STO_10) exhibits exceptional bone formation properties. Furthermore, MTT assays reveal non-cytotoxicity and high cell proliferation behaviour towards MG_63 cells even after 168 h, particularly for 25 mg/ml of high concentration, and are hemocompatible up to STO_10. Additionally, STO_10 demonstrates a 62 % reduction in the growth of E. coli and a 55 % reduction in S. aureus, highlighting its antimicrobial efficacy. These compelling in-vitro findings unveil the significant potential of STO_10 in the field of bone tissue regeneration.

Enhancing the antioxidant and anti-inflammatory potentials of mulberry-derived postbiotics through submerged fermentation with B. subtilis H4 and B. amyloliquefaciens LFB112

Mulberry-derived postbiotics (MDP) have been scientifically proven to possess beneficial properties for human health, making them potential nutraceuticals. This study aims to enhance the antioxidant and anti-inflammatory effect of MDP via submerged fermentation with Bacillus subtilis H4 (H4) and Bacillus amyloliquefaciens LFB112 (LFB112) bacterial strains. Our results demonstrated compelling evidence that the combination of two strains with the optimized time (24 h), inoculum size (8%), and substrate size (10%) significantly increased the 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activities. When compared to the non-fermented mulberry (NFM), the MDP with the above-optimized conditions showed substantially higher antioxidant activities such as DPPH, 2,2′-Azino-bis (3-ethylebenzothiazoline-6-sulfonic acid) (ABTS), hydroxyl scavenging activities, and reducing power capabilities. Moreover, the MDP showed a significant decrease in the lipopolysaccharides (LPS)-induced reactive oxygen species (ROS) generated in RAW264.7 cells. The antibacterial assays such as minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) showed that MDP possesses antibacterial activity against various pathogenic bacterial strains with the lowest MIC recorded as 32.5 mg/ml against S. pullorum CVCC519, while the highest MIC observed was 40 mg/ml against P. aeruginosa. The lowest and highest MBCs observed were 40 and 55 mg/ml against S. aureus ATCC43300 and S. pullorum CVCC519 respectively. Furthermore, the MDP showed good ant-inflammatory activities by significantly reducing the nitric oxide (NO) concentration (p<0.0001) and mRNA expression of the proinflammatory cytokines in response to the LPS-induced inflammation in the RAW264.7 macrophage cell line. To sum up, our findings indicate that MDP as a novel postbiotics can be utilized both as a functional food and a safe feed additive, possibly benefiting gut and metabolic health.

Optimization of vacuum impregnated nutmeg rind candy using RSM modeling: effect on functional and nutritional properties.

Vacuum impregnation (VI) stands as an innovative technique, used to create novel food formulations by impregnating vital nutritive compounds into natural food matrices. Process variables were syrup temperature ranging from (50 to 70°C), syrup concentration (60° to 80° Brix), and VI duration (10 to 20min). The optimal conditions emerged at 66.81°C for syrup temperature, 71.58° Brix for syrup concentration, and a precise 11.59min for the VI duration. At these paramount conditions, the candy exhibited striking attributes such as 50.0% water loss, 12.23% sugar gain, chewiness of 9N, and lightness value of 22.17. The predicted values using the developed model were validated with experimental data and indicated the adequacy of the generated model. The functional characterization of the optimized nutmeg rind candy showcased a marked reduction in myristicin content, signifying an augmented level of safety for consumption. Furthermore in-vitro anti-bacterial assay, total phenolics, flavonoids and tannin content, anti-oxidant potential, proximate composition and microstructure of the optimized candy were analysed.

N-Acetyl Cysteine-Decorated Nitric Oxide-Releasing Interface for Biomedical Applications.

Biomedical devices are vulnerable to infections and biofilm formation, leading to extended hospital stays, high expenditure, and increased mortality. Infections are clinically treated via the administration of systemic antibiotics, leading to the development of antibiotic resistance. A multimechanistic strategy is needed to design an effective biomaterial with broad-spectrum antibacterial potential. Recent approaches have investigated the fabrication of innately antimicrobial biomedical device surfaces in the hope of making the antibiotic treatment obsolete. Herein, we report a novel fabrication strategy combining antibacterial nitric oxide (NO) with an antibiofilm agent N-acetyl cysteine (NAC) on a polyvinyl chloride surface using polycationic polyethylenimine (PEI) as a linker. The designed biomaterial could release NO for at least 7 days with minimal NO donor leaching under physiological conditions. The proposed surface technology significantly reduced the viability of Gram-negative Escherichia coli (>97%) and Gram-positive Staphylococcus aureus (>99%) bacteria in both adhered and planktonic forms in a 24 h antibacterial assay. The composites also exhibited a significant reduction in biomass and extra polymeric substance accumulation in a dynamic environment over 72 h. Overall, these results indicate that the proposed combination of the NO donor with mucolytic NAC on a polymer surface efficiently resists microbial adhesion and can be used to prevent device-associated biofilm formation.

Antibacterial activity of Sarcocephalus latifolius and Acacia sieberiana, and the effect of their association with antibiotics against multidrug-resistant Staphylococcus aureus

Background: Infectious diseases continue to wreak havoc around the world causing directly or indirectly 17 million deaths per year. The present study was carried out to evaluate the in vitro antibacterial activity of the methanol extracts from the root of Sarcocephalus latifolius and from the leaves of Acacia siberiana, and their ability to potentiate the action of antibiotics against multidrug-resistant (MDR) Staphylococcus aureus. Methods: The antibacterial assays were performed using the broth microdilution method, and the extracts were screened for phytochemicals using standard qualitative methods. The effect of Sarcocephalus latifolius root extract on the functioning of H+/ATPases proton pumps of ATCC25923 Staphylococcus aureus was determined using a standard qualitative method. Results: The extracts of Sarcocephalus latifolius and Acacia siberiana had minimum inhibitory concentrations (MIC) ranging from 16 to 1024 µg/mL and 32 to 1024 µg/mL, respectively, with action spectra of 93.75% and 87.5% against the 16 strains of Staphylococcus aureus tested. The S. latifolius root extract contained alkaloids, phenols, and terpenoids as the main classes of secondary metabolites. In contrast, the A. siberiana leaf extract contained phenols and terpenoids as the major classes of secondary metabolites. The S. latifolius extract enhanced the activity of penicillin against 100% of the isolates tested. On the other hand, the A. siberiana extract enhanced the activity of Cefixime against 85.71% of the isolates tested with a 128-fold increase in activity. Conclusion: The results obtained in this study provide significant data that could potentially support the use of Sarcocephalus latifolius and Acacia siberiana in combating bacterial infections caused by multidrug-resistant Gram-positive Staphylococcus aureus.

The effect of extraction method on biological activity and phytochemical content of Artocarpus heterophyllus (jackfruit) leaves extract concurrent with its principal component analysis

Artocapus heterophyllus (jackfruit) is available in abundance in tropical regions. The present study explored the effect of different extraction method i.e. maceration, ultrasonication and both of ultrasonication and maceration on its biological activity (antioxidant, antidiabetes and antibacterial activities) and phytochemical content of Artocarpus heterophyllus (jackfruit) leaves extract. Jackfruit leaves were extracted using ethanol as solvent. The capability of jackfruit leaves extract to scavenge radicals was evaluated using a DPPH (2,2-diphenyl-1-picryl-hydrazyl) assay, β-carotene bleaching assay and reducing power assay. The total phenolic content (TPC) was assessed using the Folin- Ciocalteau method. Its antibacterial activity was assessed using the disc diffusion and microdilution method against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella typhimurim and Escherichia coli. The α-glucosidase inhibitor assay was conducted using α-glucosidase from Saccharomyces cerevisiae. The results revealed that ulrasonication method give the highest antioxidant activity in three metode used, i.e. DPPH assay with IC50 of 42.51 µg/mL, β-carotene bleaching assay of 57.64%, reducing power assay of 919 mg GAE/g. Meanwhile, for α-glucosidase inhibitory assay, ultrasonication method also had the highest value of 83.44% at concentration of 1000 µg/mL. Furthermore, antibacterial assay using disk diffusion method showed ultrasonication had the highest inhibition zone of 7.81 mm at 5 mg/mL against P. aeruginosa, while maceration method had the highest inhibition zone of 8.02 mm at 5 mg/mL against E. coli. These results in accordance with total phenolic content (TPC) of ultrasonication extract which was the highest of 125.06 mg GAE/g. The liquid chromatography-high-resolution mass spectrometry (LC-HRMS) analysis suggested that several bioactive compounds such as phenolic, flavonoid and its derivatives was present in the jackfruit leaves extract. Further analysis using principal component analysis (PCA) revealed that the extraction process affected the metabolite composition of the samples which was confirmed by significant separation of the score plots of extraction methods. The present study revealed that jackfruit leaves is a potent source of natural antibacterial, antioxidants and antidiabetic medicines in functional foods and pharmaceutical industries.

Synthesis, spectroscopic, biological and structural characterizations for the gold(III), platinum(IV), and Ruthenium(III) ceftriaxone drug complexes

Three new metal complexes of ceftriaxone (cef), incorporating platinum(IV), gold(III), and ruthenium(III), were prepared. The complexes were prepared using a 1:2 molar ratio between ceftriaxone sodium salt (Na2cef) to AuCl3, PtCl4, and RuCl3 salts in methanol solvent. The as-synthesized complexes were characterized using microanalytical techniques for C, H, N, and S elements, magnetic and molar conductance measurements, as well as spectroscopic methods including FTIR, 1H NMR, and UV-Vis. The shape, morphology and size calculations have been examined using SEM, TEM, and X-ray diffraction data. The cef complexes were six-coordinate systems possessing a distorted octahedral geometry. Through the oxygen of both triazine and carboxylate moieties with the chemical formulae [Au(cef)2(Cl)(H2O)] (I), [Pt(cef)2(Cl)2] (II), and [Ru(cef)2(Cl)(H2O)] (III) the antibiotic cef acts as a bidentate ligand towards three metal ions. The newly created complexes demonstrated antibacterial activity showing efficacy in comparison to the cef sodium ligands. In vitro, antibacterial assays against specific microorganisms were evaluated to assess the antibacterial activities of the complexes. Cytotoxicity assays for cef complexes were conducted for HepG-2 and MCF-7 cell lines, representing human hepatocellular carcinoma and breast cancer, respectively. A value of 22.4 g and 26.2 g for 50% inhibitory concentration (IC50), respectively, for HepG-2 and MCF-7 were obtained for [Ru(cef)2(Cl)(H2O)] (III). KEY WORDS: Ceftriaxone sodium, Gold, Ruthenium, Platinum, Complexes, FTIR, IC50 Bull. Chem. Soc. Ethiop. 2024, 38(4), 937-948. DOI: https://dx.doi.org/10.4314/bcse.v38i4.10