Nucleic Acid Leakage Research Articles

Polygonatum sibiricum Extract Inactivates Cronobacter sakazakii Isolated from Powdered Infant Formula.

This study aimed to investigate the antibacterial activity and mechanism of Polygonum sibiricum extract (PSE) against Cronobacter sakazakii (C. sakazakii) isolated from powdered infant formula (PIF). The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and growth curves were measured to evaluate the antibacterial effects. The antibacterial mechanism was elucidated by revealing the changes in cell membrane potential, intracellular reactive oxygen species (ROS) level, cell membrane permeability, protein and nucleic acid leakage, and cell morphology of C. sakazakii. The antibacterial effects of PSE against C. sakazakii in biofilm on stainless steel and in PIF were further analyzed. The results showed that the MIC and MBC of PSE against C. sakazakii were 4 mg/mL and 8 mg/mL, respectively. The growth of C. sakazakii can be completely inhibited by two MIC of PSE. Cell membrane depolarization, increased and then decreased intracellular ROS content, significantly increased cell membrane permeability (p < 0.05), more leakage of intracellular protein and nucleic acid, and severely damaged cell morphology were found in C. sakazakii after treatment with PSE. Furthermore, PSE can significantly reduce the viable bacteria count of C. sakazakii in biofilm on stainless steel and in PIF (p < 0.05). These findings suggest that PSE has the potential to serve as a natural antibacterial agent to reduce contamination by C. sakazakii in PIF.

Ultrasonic-assisted preparation of rose oil nanoemulsion: Characterization, anti-Escherichia coli activity, and its application in cucumber juice.

Ultrasonic-assisted preparation of rose oil nanoemulsion: Characterization, anti-Escherichia coli activity, and its application in cucumber juice.

Sucrose laurate and nisin synergistically inhibit Bacillus subtilis by multiple antibacterial targets and play promising application potential in bread preservation.

Sucrose laurate and nisin synergistically inhibit Bacillus subtilis by multiple antibacterial targets and play promising application potential in bread preservation.

Ultra-short lipopeptides containing d-amino acid exhibiting excellent stability and antibacterial activity against gram-positive bacteria.

Ultra-short lipopeptides containing d-amino acid exhibiting excellent stability and antibacterial activity against gram-positive bacteria.

Chemical Profiling and Antibacterial Potential of Methanol Extract of Solanum xanthocarpum Fruits against Methicillin-Resistant Staphylococcus aureus: Implications for AMR Management.

To investigate the antimicrobial potential of methanol fruit extract of Solanum xanthocarpum against Methicillin-Resistant Staphylococcus aureus (MRSA) and elucidate its mode of action. The rise of antimicrobial resistance (AMR) demands the exploration of alternative therapeutic strategies to combat resistant pathogens. To evaluate the efficacy of Solanum xanthocarpum methanol extract against MRSA, and identify its active constituents and mechanism of action. The fruits of Solanum xanthocarpum were extracted using various solvents, with hexane and methanol yielding the highest results. Microbroth dilution assays assessed antimicrobial activity, while in vitro assays such as Alamar blue, Scanning Electron Microscopy (SEM), protein, and nucleic acid leakage examined metabolic disruption and cell membrane integrity. Gas Chromatography- Mass Spectrometry (GC-MS) was used to identify active compounds, and molecular docking studies assessed interactions with key MRSA proteins. The methanol extract demonstrated significant antimicrobial activity against MRSA, causing metabolic disruption and leakage of cellular contents as evidenced by various in vitro assays including alarm blue, SEM, and protein and nucleic acid leakage assay. GC-MS analysis identified alpha-linoleic acid and palmitic acid as key active components. Molecular docking studies confirmed their inhibition of beta-lactamase activity, cell wall biosynthesis, efflux pumps, and virulence factors. The findings suggest that Solanum xanthocarpum methanol fruit extract has promising potential as a natural remedy against AMR associated with MRSA.

Microbial diversity and antibacterial mechanism of slightly acidic electrolyzed water against Pseudomonas fluorescens in razor clam during storage.

Microbial diversity and antibacterial mechanism of slightly acidic electrolyzed water against Pseudomonas fluorescens in razor clam during storage.

Peppermint Essential Oil For Controlling Aspergillus flavus and Analysis of its Antifungal Action Mode.

Aspergillus flavus contamination has long been a major problem in the food and agriculture industries, while peppermint essential oil (PEO) is increasingly recognized as an effective alternative for controlling fungal spoilage. However, its biocontrol effect and action mode on A. flavus have rarely been reported. Here, the inhibition rates of PEO on A. flavus were determined by the plate fumigation and mycelial dry weight method. The minimum inhibitory concentration (MIC) was identified as 0.343 μL/mL. In the biocontrol tests, the moldy rates of maize kernels, wheat grains, and peanut kernels in the PEO treatment group were significantly reduced by 65%, 72%, and 63.33%, respectively. The biocontrol efficacy of PEO on maize kernels, wheat grains, and peanut kernels reached 80.67%, 82%, and 67.67%, respectively. Furthermore, antifungal action mode analysis showed that PEO changed the mycelial morphology, damaged the integrity of cell wall and membrane. Moreover, it reduced the ergosterol content, elevated the malondialdehyde content, increased the relative conductivity, and led to the intracellular leakage of nucleic acids and proteins, thereby enhancing the cell membrane permeability. In addition, PEO decreased the antioxidant-related catalase (CAT) and superoxide dismutase (SOD) activities, significantly increased the hydrogen peroxide (H2O2) content, and induced the accumulation of reactive oxygen species (ROS) in the mycelia. In conclusion, this study confirms that PEO, as an effective natural antimicrobial agent, has good application prospects in controlling the spoilage of A. flavus during grain storage and preventing food mold.

Zinc–Silver Nitroprusside Nanocomposites: Synthesis, Characterization, and Antibacterial Properties with Cytocompatibility

The emergence of bacterial infections poses an enormous health, economic, and global burden on organisms. However, silver‐based materials with strong antibacterial activity are difficult to apply due to the high toxicity. Therefore, zinc–silver nitroprusside nanocomposites (Zn–AgNP NCs) are prepared using sodium nitroprusside as a medium and characterized to achieve enhancement of their antibacterial properties and reduction of their cytotoxicity. Herein, the Zn–AgNP NCs show a cubic shape with an average size of 161.23 ± 3.77 nm and exhibit a negative zeta potential (–25 ± 0.23 mV). The Zn–AgNP NCs exhibit crystalline properties similar to those of silver nitroprusside nanoparticles (AgNP NPs) and zinc nitroprusside nanoparticles (ZnNP NPs). Furthermore, Zn–AgNP NCs demonstrate enhanced antibacterial and anti‐biofilm activities against multiple pathogens, including Bacillus cereus (MIC50 = 8.8 μg mL−1), and induce high levels of nucleic acid and protein leakage in bacteria. In addition, Zn–AgNP NCs demonstrate low cytotoxicity (below 15.6 μg mL−1) and high biocompatibility (up to 250 μg mL−1). Overall, Zn–AgNP NCs exhibit excellent antibacterial capabilities and superior biocompatibility compared to AgNP NPs. This study suggests that Zn–AgNP NCs have the potential to be utilized as a safe and effective antibacterial agent.

Chestnut flower extract as a natural inhibitor of Fusarium graminearum: antifungal activity and mechanisms.

Plant pathogenic fungi are a major contributor to reductions in crop yield and quality, posing significant challenges to global food security. The extensive application of chemical fungicides has led to the development of resistance in pathogenic fungi and the accumulation of harmful residues, which threaten environmental sustainability and human health. Plant-derived fungicides, with low toxicity and broad-spectrum activity, offer an eco-friendly alternative to synthetic chemicals. This study evaluated the antifungal activity of chestnut flower extract (CFE) against Fusarium graminearum (FG) and investigated its underlying mechanisms through cellular and transcriptomic analyses. Liquid chromatography-mass spectrometry (LC-MS) identified phenolic acids and flavonoids as the primary active constituents of CFE. CFE inhibited mycelial growth and spore germination with median effective concentration (EC50) values of 2.51 and 0.39 mg mL-1, respectively. It disrupted biofilm integrity and membrane permeability by reducing ergosterol content, increasing extracellular conductivity, and affecting malondialdehyde (MDA) levels. Protein and nucleic acid leakage were observed. Additionally, CFE inhibited energy metabolism by reducing adenosine triphosphate (ATP) levels and suppressing the activities of key respiratory enzymes, including succinate dehydrogenase (SDH), malate dehydrogenase (MDH) and nicotinamide adenine dinucleotide (NADH) dehydrogenase. Transcriptomic analysis further revealed that CFE affected multiple biological processes in FG, including cell structure, protein synthesis, ion transport and mitochondrial function. The chestnut flower contains active antibacterial ingredients that exhibit targeted inhibition of FG, thereby providing theoretical and technical support for the development of natural antibacterial agents with specific targeting capabilities. © 2025 Society of Chemical Industry.

The Antibacterial Activity and Mechanisms of a Mixed Bio-Preservative on the Bacillus Stains in Crab Roe Sauce.

Crab roe sauce (CRS) is prone to spoilage due to microbial contamination. Therefore, this study aimed to investigate the inhibitory effects and mechanisms of a mixed bio-preservative (0.025% ε-polylysine hydrochloride (ε-PL) + 0.01% nisin (NS) + 0.01% tea polyphenols (TPs)) on the specific spoilage bacteria (SSB) in CRS. First, the SSB in CRS were isolated and identified by 16S rRNA sequencing. Two isolates were selected as representative strains based on their enzymatic spoilage potential and spoilage capability in CRS. By comparing the inhibition zones, ε-PL, NS, and TPs were selected from five conventional bio-preservatives (ε-PL, NS, TPs, grape seed extract (GSE), and rosemary extract (RE)) to prepare the mixed bio-preservative. The results showed that the minimum inhibitory concentration (MIC) of the mixed bio-preservative against Bacillus pumilus and Bacillus subtilis was 56.3 µg/mL. The growth curves and cell viability tests revealed that the mixed bio-preservative reduced the viability of both strains. The conductivity, alkaline phosphatase activity, and nucleic acid and soluble protein leakage indicated that the mixed bio-preservative disrupted the integrity of the cell walls and membranes of the two isolates in a concentration-dependent manner. Scanning electron microscopy further confirmed the damage to the cell membranes of the two isolates by the mixed bio-preservative. Overall, the mixed bio-preservative exhibited excellently inhibitory effects on the SSB and could be a promising method for the preservation of CRS.

Antibacterial activity of zinc oxide nanoparticles against Shewanella putrefaciens and its application in preservation of large yellow croaker (Pseudosciaena crocea).

Antibacterial activity of zinc oxide nanoparticles against Shewanella putrefaciens and its application in preservation of large yellow croaker (Pseudosciaena crocea).

Synergistic inactivation and mechanism of thermosonication treatment combined with germinants and licorice extracts against Paraclostridium bifermentans.

Synergistic inactivation and mechanism of thermosonication treatment combined with germinants and licorice extracts against Paraclostridium bifermentans.

Antifungal effect and control of Alternaria fruit rot in blueberry through ε-polylysine hydrochloride.

Antifungal effect and control of Alternaria fruit rot in blueberry through ε-polylysine hydrochloride.

Synergistic Anti-Helicobacter pylori Effects of Takifugu obscurus Skin Peptides and Lactobacillus plantarum: A Potential Gastric Health Dietary Supplement.

Helicobacter pylori (H. pylori) infection is a widespread gastric infectious disease, posing significant challenges due to the increasing prevalence of antibiotic resistance. This study aimed to evaluate the synergistic antibacterial activity of Takifugu obscurus skin peptides (TSPs) and the cell-free supernatant of Lactobacillus plantarum WUH3 (LCFS) in developing a potential green and efficient dietary supplement therapy. Using enzymatic hydrolysis and ultrafiltration techniques, the most bioactive peptide fraction, TSPb (1-3 kDa), was identified. The effects of TSPb and LCFS-both individually and in combination-on H. pylori biofilm function, membrane morphology, and internal structure were systematically analyzed using urease activity, N-phenyl naphthylamine (NPN) uptake, nucleic acid leakage, scanning electron microscopy (SEM), and infrared (IR) spectroscopy. The results showed that both LCFS and TSPb significantly inhibited H. pylori urease activity, with inhibition rates of 53.60% and 54.21% at 24 h, respectively, and the highest inhibition rate of 74.64% was observed with their combined treatment. SEM, NPN fluorescence, and nucleic acid leakage analyses revealed distinct mechanisms of action for each treatment. LCFS treatment caused membrane surface loosening and morphological deformation, while TSPb induced the formation of localized membrane pores. IR spectroscopy further confirmed that the combined treatment led to a more severe disruption of the lipid and protein structure within the bacterium. Overall, compared to individual treatments, the combination of TSPb and LCFS exhibited enhanced intracellular penetration and a more significant effect on bacterial viability. This study successfully identified TSPb as a highly bioactive peptide and elucidated its potential synergistic antibacterial mechanism with LCFS. These findings provide scientific evidence for the development of functional antimicrobial foods and gastric health dietary supplements, offering a promising strategy for the prevention and management of H. pylori infections.

Evaluation of extracts from Phyllostachys makinoi for their antibacterial and accelerated wound healing potential

Phyllostachys makinoi, an endemic bamboo species in Taiwan, is underutilized, despite its rich forest resources. Known for its antioxidant, anti-inflammatory, and antibacterial properties, this study explores the antimicrobial, anti-inflammatory, and wound-healing activities of P. makinoi extracts. The antibacterial potential of P. makinoi extracts was first evaluated using the agar diffusion method, along with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays. Subsequently, electron microscopy and a conductivity meter were employed to assess whether P. makinoi extracts exert antibacterial effects by disrupting bacterial cell structures. Finally, the anti-inflammatory and cell proliferation-promoting effects of P. makinoi extracts were assessed in RAW264.7 and CCD-1112Sk cell models. The MIC and MBC of the P. makinoi water extracts against two multidrug-resistant Staphylococcus aureus strains were 4 and 16–32 mg/mL, respectively, while those for ethanol extracts were 2 and 32 mg/mL, respectively. In the time-kill assay, both strains were killed after treatment with extracts for 12 and 18 h. Scanning electron microscopy revealed that the bacterial cells treated with the extracts appeared rough, ruptured, and shriveled. The extracts disrupted the cell membranes, causing electrolyte, protein, and nucleic acid leakage, leading to cell death. Additionally, P. makinoi extracts reduced lipopolysaccharide-induced nitric oxide, tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 levels in RAW264.7 cells, and promoted wound healing by enhancing CCD-1112Sk cell proliferation. In conclusion, P. makinoi water and ethanol extracts demonstrated antibacterial and anti-inflammatory effects, showing potential for treating wound infections and accelerating healing, making them promising candidates for wound-healing therapies.

Antifungal lipopeptides from the marine Bacillus amyloliquefaciens HY2-1: A potential biocontrol agent exhibiting in vitro and in vivo antagonistic activities against Penicillium digitatum.

Antifungal lipopeptides from the marine Bacillus amyloliquefaciens HY2-1: A potential biocontrol agent exhibiting in vitro and in vivo antagonistic activities against Penicillium digitatum.

Efficacy of Terminalia catappa Leaves Extract As An Antimicrobial Agent Against Pathogenic Bacteria

Terminalia catappa (“Ketapang” in Malay) is a plant that belongs to the family Combreteceae and is native to Southeast Asia. Various parts of this plant were reported to possess bioactive compounds with antimicrobial properties. However, reports on the antimicrobial activity of different ages of T. catappa leaf (TCL) against pathogenic bacteria are lacking. This study investigated the antibacterial activity of the different ages of TCL extracts against the pathogenic bacteria, Staphylococcus aureus and Escherichia coli. Disk diffusion assay was carried out to determine the antibacterial activity of different ages of TCL extracts. Meanwhile, the efficacy of the different leaf extracts was evaluated by performing broth microdilution (MIC &amp; MBC determination), growth reduction, time-kill study, and membrane cell leakage assay (MCLA). The findings revealed that the extracts showed greater antibacterial activity toward the Gram-positive S. aureus compared to Gram-negative E. coli, with diameter of inhibition zone ranging from 12.33±0.53 mm to 26.33±1.4 mm and 9.23±0.32 mm to 16.21±0.42 mm, respectively. The mature leaf extract (MLE) and senescent leaf extract (SLE) exhibited higher antibacterial activity compared to young leaf extract (YLE) and shoot leaf extract (ShLE) for both Gram-positive and Gram-negative bacteria. The broth microdilution assay showed all the different ages of TCL extracts exhibited bactericidal effects towards S. aureus. Meanwhile, the YLE and ShLE showed a bacteriostatic effect on E. coli, whereas the MLE and SLE exerted bactericidal action. The time-kill study revealed that the extract activity was time- and concentration-dependent. The results of the MCLA corroborated the time-kill study, which showed that a higher concentration of extract could successfully inhibit and kill the bacterial cells, as indicated by higher protein and nucleic acid leakage. The present study suggests that all different ages of TCL extracts, particularly the MLE can act as potential antibacterial agents against both Gram-positive and Gram-negative bacteria.

Constituents, Antioxidant and Antibacterial Abilities of Essential Oil of Dolichos lablab Flowers and Its Application as Food Preservative

ABSTRACTDolichos lablab flowers, as the dried buds of D. lablab L, was used as an ingredient in various dishes in China, and there were no studies on the constituents, antioxidant and antibacterial activity with the essential oil. The constituents, antioxidant and antibacterial ability of the essential oil of D. lablab flowers (EOF) obtained by hydro‐distillation (HD) method were evaluated, and its efficacy in fresh pork preservation was studied. The 36 components were recognised, accounting for 96.46% of EOF. The proportion of oxygen‐containing compounds in EOF was as high as 89.72%, of which fatty acid accounted for 65.82%. Among fatty acids, palmitic acid (33.86%), myristic acid (8.42%), lauric acid (5.42%) and 2E‐dodecenoic acid (4.46%) were identified as the major compounds. EOF had an excellent antioxidant ability. The semi‐radical scavenging concentrations (IC50) of EOF for 2,2‐Diphenyl‐1‐picrylhydrazyl (DPPH−), 2,2′‐Azinobis‐(3‐ethylbenzthiazoline‐6‐sulphonate) (ABTS+) and liposomal peroxidation were 3.09, 2.46 and 0.82 mg/mL. EOF also showed good antibacterial ability, including Bacillus subtilis, Listeria monocytogenes, Escherichia coli and Staphylococcus aureus. And the L. monocytogenes showed the highest sensitivity to EOF with the minimum inhibitory concentration (MIC) of 1.25 μg/mL and the minimum bactericidal concentration (MBC) of 2.5 μg/mL. Further research showed that EOF achieved its antibacterial effect by destroying the functional and structural integrity of cell membranes and cell walls of L. monocytogenes, leading to the leakage of alkaline phosphatase (AKP), nucleic acids and proteins, ultimately leading to L. monocytogenes death. The pork fresh‐keeping results showed that 1.0% EOF extend the shelf‐life of pork up to day 6, which was 2.00 times than the control during 7 days of refrigeration at 4°C. This study will provide the fundamental data support for future potential applications of EOF in food preservation.

Antifungal activity of dimethyl trisulfide and potential biocontrol against Alternaria alternata on postharvest Lycium barbarum

Lycium barbarum, is a medicine-food homology plant, so sustainable control of the postharvest Goji berry black mold caused by Alternaria alternata is particularly critical. In this paper, the impact of dimethyl trisulfide (DMTS) on A. alternata was studied, as well as the effects of DMTS on hypha ultrastructure, membrane permeability, reactive oxygen production, and essential enzymes of the cellular defense system. DMTS was shown to significantly inhibit the spore germination and hyphal growth of A. alternata in a concentration-dependent manner. The results of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that A. alternata cells were separated between cytoplasm and cell wall, organelles such as mitochondria were vacuolate or even disappeared, and the cytoplasm was fused. PI staining, conductivity measurements, and intracellular nucleic acid and protein content measurements showed that the permeability of the cell membrane changed after DTMS treatment, leading to the leakage of intracellular nucleic acid and protein. DMTS could also cause the accumulation of hydrogen peroxide (H2O2) and malondialdehyde (MDA), thus causing membrane oxidative damage. Through directly destroying the fungal cell and indirectly inducing membrane damage, DMTS can control the postharvest Goji berry black mold, and is a potential application prospect in the control of postharvest diseases.

Antibacterial activity of Azanza garckeana extracts (Malvaceae) in vitro and their potential use in respiratory infections

Antibacterial activity of Azanza garckeana extracts (Malvaceae) in vitro and their potential use in respiratory infections