Curcuma sahuynhensis Škorničk. & N.S. Lý has been discovered recently whose antiviral potential is unknown, thus deserved for discovery-phase screening. A combination of experimental characterization, quantum calculation, molecular docking simulation, physicochemical analysis, and absorption, distribution, metabolism, excretion, and toxicity (ADMET) was designed for the theoretical argument on the potentiality of oil-based components (1−27) against H5 hemagglutinin in influenza A virus (PDB-5E32), wild-variant SARS-CoV-2 main protease (PDB-6LU7), and SARS-CoV-2 Omicron spike protein (PDB-7T9J). Theoretical arguments based on various computational platforms specify the most promising bio-inhibitors, i.e. 23 (bio-compatibility: ground energy −966.73 a.u., dipole moment 3.708 Debye; bio-inhibitability: DS ̅ \bar{{\rm{DS}}} −12.5 kcal mol⁻¹; drug-likeness: mass 304.7 amu, log P 1.31; polar-interactability: polarizability 32.8 ų) and 26 (bio-compatibility: ground energy −1393.66109 a.u., dipole moment 5.087 Debye; bio-inhibitability: DS ̅ \bar{{\rm{DS}}} −11.9 kcal mol⁻¹; drug-likeness: mass 437.5 amu, log P 4.28; polar-interactability: polarizability 45.7 ų). The pkCSM-ADMET model confirms their favorable pharmacokinetics and pharmacology. The total essence is unsuitable for use as an antiviral source in its pure form since the most bioactive candidates are accountable for the small content. Particularly, 23 (7β-hydroxydehydroepiandrosterone) and 26 (ethyl cholate) are recommended for further experimental efforts of isolation and bioassaying trials.

Background: Pseudomonas aeruginosa (PA) is a significant cause of nosocomial infections, particularly because its ability to form biofilms on medical devices complicates treatment. This study developed a biofilm model using a drip flow reactor (DFR) system and apply it to investigate the effects of antibiotics on biofilm formation. Methods: The biofilm-forming capacity of PA strains ATCC 9027, ATCC 27853, and PA 01 (a PA isolate from wastewater samples) was evaluated using a DFR system. This model was then used to assess biofilm resistance to antibiotics through flow cytometry analysis. Results: A PA biofilm model was successfully established in the DFR system, as evidenced by images of the carrier and flow cytometry analysis results. Significant differences in biofilm formation were observed among the tested strains (one-way ANOVA, P < 0.01). The timing of antibiotic administration was found to influence biofilm formation. The combination of colistin and rifampicin exerted a synergistic effect, significantly enhancing both the inhibition of biofilm formation and the destruction of existing biofilms compared with individual antibiotic treatments (one-way ANOVA, P < 0.01). Conclusion: This study successfully developed a PA biofilm model using the DFR system and applied it to evaluate the efficacy of colistin and rifampicin, both individually and in combination, against PA biofilms. The DFR model, coupled with flow cytometry analysis, is a valuable tool for investigating biofilm formation kinetics and assessing the impact of antibiotics on biofilm development and eradication.

Introduction: Acinetobacter baumannii (A. baumannii) is a major cause of hospital-acquired infections and frequently harbors antibiotic-resistance genes that complicate treatment. Rapid identification and resistance gene detection are essential for effective antibiotic use and infection control. This study developed a multiplex polymerase chain reaction (PCR) assay to identify A. baumannii and detect key β-lactam resistance genes for clinical isolates. Methodology: The assay targeted the recA gene and the 16S-23S ribosomal RNA internal transcribed spacer region for A. baumannii identification. In addition, five β-lactamase genes (blaOXA-51-like, ampC, blaCTX-M, blaTEM, and blaSHV) were targeted. Antimicrobial susceptibility testing and phenotypic extended-spectrum beta-lactamase detection were performed to confirm resistance profiles. Results: Of the 49 Acinetobacter isolates, 46 were identified as A. baumannii by multiplex PCR. All 46 isolates contained ampC, and 45 harbored blaOXA-51-like. blaTEM was detected in 34 isolates, whereas blaCTX-M and blaSHV were absent. Phenotypic tests showed general agreement with the PCR results. High resistance rates were observed for multiple antibiotic classes, including carbapenems, cephalosporins, and aminoglycosides. Conclusions: The multiplex PCR assay developed here provides a rapid and reliable method for A. baumannii identification and resistance gene detection, outperforming conventional methods in terms of speed and accuracy. The high resistance rates observed highlight the urgent need for effective diagnostic tools and infection control strategies to combat multidrug-resistant A. baumannii.

Myxobacteria are known to produce epothilone, a natural macrolide compound with significant antitumor activity achieved through the inhibition of microtubules formation during cell division, which is a mechanism critical to chemotherapy. This study investigated the antifungal and antitumor activities of myxobacteria isolated from soils enriched with decomposed plant material. Myxobacterial strains were isolated and screened by examining macroscopic characteristics, assessing cellulose degradation using filter paper as the sole carbon source, and observing the presence of fruiting bodies and motility on slides. Selected strains were cultured in CK6 medium containing Amberlite XAD-16 resin, and active compounds were eluted using methanol. Antifungal activity was evaluated using disk diffusion and thin-layer chromatography autography, and cytotoxicity was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Among the 41 soil samples, three strains (QN01, QN02, and QN04) demonstrated cellulose degradation capability and exhibited morphological characteristics consistent with the Sorangium sp. The QN02 strain exhibited antifungal activity against pathogens, including Trichophyton rubrum, Trichophyton mentagrophytes, Microsporum gypseum, Aspergillus flavus, Aspergillus niger, Aspergillus fumigatus, Penicillium sp., and Mucor sp. Furthermore, extracts from QN02 inhibited MCF-7 breast cancer cells (IC50=159.1 ng/mL) and human embryonic kidney cells (HEK-293) human kidney cells (IC50=528.1 ng/mL). The QN02 strain is a promising source of antifungal and antitumor compounds.

Yen NTN, Chung DD, Hong NTK, Cham NP, Nhan VT, Linh DTL, Ngoc NLB, Thai NM, Nga ND, Anh NT. 2023. Isolation, phylogenetic analysis and bioprospection of myxobacteria from Vietnam. Biodiversitas 24: 5653-5663. Myxobacteria have been considered microbial factories for producing secondary metabolites that have a variety of potential biological actions for discovering and isolating new biological molecules. Myxobacteria were isolated from soil samples collected in some provinces/cities in Vietnam. The purified isolates were identified based on morphology, biochemical test and phylogenetic analysis inferred from 16S rRNA gene. High-throughput screening assays including 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DDPH) for antioxidant properties and microdilution for antimicrobial activity were performed with myxobacterial extracts. Compounds from potential strain were predicted using liquid chromatography coupled with mass spectrometry. Forty-three myxobacterial strains were isolated and classified into seven genera of Angiococcus, Archangium, Chondromyces, Corallococcus, Cystobacter, Melittangium, and Myxococcus. The extract from CT21 strain had the highest total antioxidant activity (IC50 = 52.34 ± 1.47 and 30.28 ± 0.74 ?g/mL for the DPPH and ABTS, respectively). It is worth noting that all strains isolated myxobacterial strains show inhibitory activity against at least one of the tested microorganisms. The most potent antimicrobial strain was Myxococcus stipitatus GL41, which inhibited all tested microorganisms, and the minimal inhibitory concentration (MIC) values were 1 ?g/mL against methicillin-resistant Staphylococcus aureus (MRSA), methicillin-sensitive Staphylococcus aureus (MSSA), Streptococcus faecalis, Candida albicans, and Aspergillus niger. Mass spectrometry analysis revealed the presence of althiomycin - the polyketide antibiotic from ethyl acetate fraction. In the present study, myxobacteria were isolated from soil sample collected from Vietnam, analyzed phylogenetically, and screened for biological activities.