Martyna Kasela

Essential oils (EOs) are widely investigated as multifunctional agents for cosmetic applications due to antimicrobial and antioxidant properties; however, their efficacy and safety depend on chemical composition and microbiological selectivity. This study characterized ten commercially available EOs (basil, lavender, melissa, mint, oregano, rosemary, sage, thyme, clove, tea tree) and evaluated their antistaphylococcal and antioxidant activities. Chemical composition was analyzed using GC-MS and ATR-FTIR spectroscopy, while antistaphylococcal activity was assessed against Staphylococcus spp. isolated from skin microbiota using the microbroth dilution method. Antioxidant capacity was determined by the DPPH assay. Multivariate statistical analyses were applied to explore chemical composition–activity relationships. The EOs showed distinct chemical profiles dominated by phenolic compounds (eugenol, carvacrol, thymol), oxygenated monoterpenes (linalool, menthol, 1,8-cineole), and terpenoids. Clove, oregano, and thyme EOs exhibited the strongest antistaphylococcal activity (MIC 0.5–2 mg/mL) and highest antioxidant capacity (>80%), whereas lavender, mint, and sage EOs showed weak effects. All EOs demonstrated bactericidal activity with consistent susceptibility patterns among Staphylococcus spp. PCA and FTIR confirmed an association between phenolic content and bioactivity. In conclusion, antimicrobial efficacy is primarily driven by phenolic composition, supporting targeted cosmetic use while acknowledging possible effects on skin Staphylococcus spp. populations.

Staphylococcus aureus is a high-priority pathogen causing skin and soft tissue infections (SSTIs). The frequent resistance to anti-staphylococcal agents exhibited by this underscores the need for accurate diagnostics to guide effective therapy. Therefore, this study aimed to compare phenotypic and genotypic resistance in S. aureus isolates from nasal carriers and SSTIs and to elucidate gene-silencing mechanisms. In total, 355 S. aureus isolates (256 isolated from carriers and 79 from SSTIs) were studied for their phenotypic and genotypic resistance to β-lactams, macrolides, tetracyclines, aminoglycosides, and mupirocin. The silenced mupA gene (low prevalence: 0.6%; 2/335), linked to mupirocin resistance, was sequenced, and expression was assessed via reverse transcription qualitative PCR (RT-qPCR) in all mupA-positive isolates. SSTI isolates showed significantly higher resistance to erythromycin, gentamicin, and mupirocin, along with a higher prevalence of multidrug-resistant strains and ermC and tetM genes. Sequencing revealed multiple mutations in silent mupA, including a critical frameshift (c.372 delA) in a poly(A) tract that brings about premature truncation. RT-qPCR indicated upregulation of silent mupA variants and high variability in functional strains, suggesting that frameshift alone prevents resistance. These findings highlight silent resistance genes as key targets for advancing S. aureus surveillance and for combating emerging threats.

This paper provides a comprehensive phytochemical analysis of extracts obtained from the leaves and roots of Hedysarum semenowii using HPLC/PDA-ESI-QToF/MS-MS techniques. The study identified 53 compounds, with flavones and isoflavones as the primary polyphenols. Notably, flavones were predominant in the leaves, while isoflavones were found mainly in the roots, potentially serving as chemotaxonomic markers. Medicarpin and its glucoside were confirmed in the roots, while mangiferin and its derivatives were identified for the first time in both the roots and leaves. Isoflavones like formononetin, calycosin, and afrormosin, along with their glucosides, were exclusive to the roots. Flavonols such as quercetin and its glycosides were abundant in the aboveground parts. Our study also identified flavones like luteolin, flavanones (naringenin), and chalcones (liquiritigenin) in various parts. Additionally, the phenolic acids gallic and ferulic acids, as well as the organic acids malic and citric acid, were also detected. The extracts demonstrated differential antimicrobial and antifungal activities in a microbroth dilution assay, with the aerial part extracts showing superior efficacy, particularly against Staphylococcus epidermidis and Pseudomonas aeruginosa. Both aerial and underground parts exhibited comparable antifungal activity against Candida species. Antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH^•) radical scavenging test varied significantly, with ethanolic extracts from the aerial parts showing the highest potential (Antioxidant Activity Index (AAI) 2.07 ± 0.13). In contrast, root extracts had consistently low antioxidant activity. The results highlight the aerial parts of H. semenowii as a more promising source of biologically active compounds with antimicrobial and antioxidant properties compared to the roots.

Geum aleppicum Jacq. (yellow avens), a species traditionally used in folk medicine, remains understudied in the ethnopharmacological aspects. In this study, we comprehensively evaluated the phytochemical composition and biological activity of a hydroethanolic (50:50, v/v) extract from the aerial parts of G. aleppicum collected in Kazakhstan. Using the high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (HPLC-ESI-QTOF-MS/MS), we identified 24 compounds, predominantly phenolic acids, flavonoids, tannins, and triterpenoids. The major compound was ellagic acid (2.28 mg/g dry extract) as revealed by the reverse phase high-performance liquid chromatography–diode array detector (RP-HPLC-DAD). The extract exhibited a high polyphenol content (131.45 mg GAE/g) and strong antioxidant activity in Ferric Reducing Antioxidant Power (FRAP) assay and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay (3.82 ± 0.07 mmol Fe²⁺/g and 106.61 ± 0.89 mg GAE/g, respectively). Antimicrobial assay of the extract revealed notable antifungal activity against Candida spp., especially against C. glabrata and C. tropicalis with minimum inhibitory concentration (MIC) of as low as 0.125 mg/mL, showing fungistatic effect. Although the extract inhibited the cytopathic effect induced by Human Herpesvirus 1 (HHV-1) in VERO cells, it did not significantly reduce viral replication. Moreover, among human cancer cell lines studied, the extract exerted moderate and selective cytotoxicity against A549 lung cancer cells (CC₅₀ = 75.51 µg/mL, SI = 9). These findings highlight G. aleppicum as a rich source of bioactive compounds, especially phenolics, supporting its potential for development of pharmaceutical and cosmetic applications.

Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder with an increasing global prevalence. The International Classification of Diseases (ICD) system typically categorizes IBS into four subtypes based on symptomatology. The objective of this review is to provide a concise synthesis of the most current information regarding IBS, encompassing widely accepted diagnostic criteria, etiology, epidemiological data and the significance of gut microbiota (GM) in pathogenesis of this disorder. Additionally, it will explore future perspectives. Recent studies have demonstrated that the GM in healthy individuals primarily consists of four main bacterial phyla: Firmicutes spp., Bacteroidetes spp., Actinobacteria spp., and Proteobacteria spp. Dysbiosis or an imbalance in these bacteria may be a contributing factor to the IBS development. It is imperative to acknowledge the multifaceted role of the GM in several essential biological processes, including: immunomodulation, intestinal barrier integrity, gut microbiota-gut-brain axis (GBA) or nutrient absorption. The composition of GM is subject to variation depending on the IBS subtype. Many therapeutic strategies have been devised for the treatment of patients with IBS, comprising antibiotics, probiotics, prebiotics, synbiotics and fecal microbiota transplantation (FMT). Although FMT has shown promise, clinical trials outcomes remain still inconsistent. Dietary interventions and psychological support are also vital components of IBS management. Despite the advances in understanding the GM-IBS relationship, there is still a lack of knowledge regarding specific microbial markers for each IBS subtype. Consequently, a definitive microbiota pattern has yet to be delineated. However, emerging evidence underscores the microbiome’s role in IBS pathophysiology.

Introduction and objective: Milking wastewater (MW) is an under-recognised reservoir of antibiotic resistant bacteria (ARB) and antimicrobial resistance genes (ARGs). The aim of the study is to evaluate MW as a point source pollutant for the presence of ARB and ARGs, to develop a treatment...

The genus Inula has been used in folk medicine for centuries; however, the data concerning Inula britannica L. are scarce. This study aimed at investigating the chemical composition of methanolic and ethanolic extracts from the aerial parts of I. britannica collected in Kazakhstan and evaluating their antimicrobial and antioxidant properties, with special attention being paid to polyphenols. The total content of polyphenols and flavonoids in the extracts was determined colorimetrically, while their qualitative and quantitative analyses were conducted using HPLC/ESI-QTOF-MS and RP-HPLC/DAD. Their antioxidant potential was determined using the FRAP and DPPH methods, whereas their antimicrobial activity was determined by the microdilution method towards a panel of reference microorganisms, including pathogens of the human gastrointestinal tract. Chemical analysis demonstrated that the methanolic extract had a higher content of polyphenols (58.02 vs. 43.44 mg GAE/g) and flavonoids (21.69 vs. 13.91 mg QUE/g) than the ethanolic extract. In both extracts, 15 compounds were identified, with the highest contents being those of cynarine (13.96 and 11.68 mg/g) and chlorogenic acid (9.22 and 5.09 mg/g). The DPPH assay showed a higher antioxidant activity of the methanolic extract (19.78 ± 0.12 mg GAE/g) in comparison to that of the ethanolic extract (15.56 ± 0.24 mg GAE/g). Similarly, the FRAP method showed that the methanolic extract exerted a much higher antioxidant activity (5.07 ± 0.18 mmol Fe²⁺/g) than the ethanolic extract (0.39 ± 0.01 mmol Fe²⁺/g). In contrast, both extracts showed similar antimicrobial properties, with the highest activity being that against Helicobacter pylori ATCC 43504 (MIC = 0.125–0.25 mg/mL). This paper presents novel data on I. britannica L., implying its significance as a source of valuable active compounds and being a prerequisite for further biological studies.

Parcel vending machines (PVMs) are receiving more recognition as an environmentally friendly last-mile delivery service. However, their high popularity creates the risk of microbial contamination of touchscreens and keypads resulting in the spread of pathogens in humans. The study aimed at assessing the degree of bacterial contamination of PVMs and characterizing the microbial population using mass spectrometry-based identification. In total, 64 PVMs located in 16 districts of city Lublin (Poland) were studied for the total number of aerobic bacteria (TNAB) using contact plates, whereas bacterial identification was conducted using the MALDI-TOF MS. Study revealed that the average TNAB for the analyzed districts ranged from 1 ± 0.4 CFU/cm² to 8.54 ± 10.77 CFU/cm². Statistical analysis showed a positive correlation between the TNAB and the population density (p = 0.0193), emphasizing the influence of human microbiota on the level of bacterial contamination. Among 140 reliably identified bacterial species (96.3%), the most prevalent were Bacillus spp. (52.8%) and Staphylococcus spp. (10.7%). Multiple opportunistic pathogens were detected, including B. cereus and Escherichia coli. This study indicates the need to develop procedures for disinfection or to implement modified materials for the PVMs touchscreens to limit the adhesion of potentially pathogenic microorganisms.

The Stachys L. genus has been widely used in traditional medicine in many countries throughout the world. The study aimed to investigate the chemical composition and bioactivity of the hydroethanolic extract (50% v/v) obtained by ultrasonication from the aerial flowering parts of Stachys sylvatica L. (SSE) collected in Almaty region (Southern Kazakhstan). According to RP-HPLC/PDA analysis the leading metabolites of the SSE belonged to polyphenols: chlorogenic acid and its isomers (2.34 mg/g dry extract) and luteolin derivatives (1.49 mg/g dry extract), while HPLC-ESI-QTOF-MS/MS-based qualitative fingerprinting revealed the presence of 17 metabolites, mainly chlorogenic acid and its isomers, flavonoid glycosides, and verbascoside with its derivatives. GC-MS analysis of the volatile metabolites showed mainly the presence of diterpenoids and fatty acid esters. A reduction in the viability of nematodes Rhabditis sp. was obtained for the SSE concentration of 3.3 mg/mL, while 11.1 mg/mL showed activity comparable to albendazole. The SSE exhibited higher activity against Gram-positive (MIC = 0.5–2 mg/mL) than Gram-negative bacteria and yeast (MIC = 8 mg/mL), exerting bactericidal and fungicidal effects but with no sporicidal activity. The SSE showed some antiviral activity against HCoV-229E replicating in MRC-5 and good protection against the cytopathic effect induced by HHV-1 in VERO. The SSE was moderately cytotoxic towards human cervical adenocarcinoma (H1HeLa) cells (CC₅₀ of 0.127 mg/mL after 72 h). This study provides novel information on the SSE extract composition and its biological activity, especially in the context of the SSE as a promising candidate for further antiparasitic studies.

Essential oils (EOs), being mixtures of various natural compounds, constitute an attractive source of novel antimicrobial agents. Along with multiple studies concerning their rich biological activity, there are different methods allowing to determine both antimicrobial activity in direct contact, as well as through the activity of vapours. Thyme constitutes one of the most common aromatic herbs used for pharmaceutical, cosmetic and culinary purposes. The aim of the study was to compare the antibacterial activity of liquid and vapour phases of Thymus vulgaris L. essential oil (TEO) against most common pathogenic Gram-positive (Staphylococcus aureus ATCC 25913, Enterococcus faecalis ATCC 29212, Bacillus cereus ATCC 10876) and Gram-negative (Escherichia coli ATCC 25922, Salmonella typhimurium ATCC 14028, Pseudomonas aeruginosa ATCC 27853) microorganisms. To determine TEO antibacterial properties, two methods were used: disc-diffusion assay so as to test activity in direct contact; disc-volatilization assay so as to determine activity in gaseous contact. Statistical analysis showed that Gram-positive bacteria were more sensitive to TEO vapours than Gram-negative (p=0.005), while in the case of disc-diffusion assay, no such differences were evident. Moreover, sensitivity towards TEO differed among Gram-positive bacteria in disc-diffusion (p=0.009) and disc-volatilization assay (p=0.001). Among Gram-negative rods, a statistically higher sensitivity regarding E. coli was noted when compared to S. typhimurium in both direct (p=0.011) and gaseous (p=0.006) TEO contact. No activity of TEO against P. aeruginosa was found. As thyme essential oil exhibited significant antimicrobial activity against Gram-positive bacteria in gaseous contact, this justifies its use as an addition to inhalation agents to prevent or support the treatment of upper respiratory tract infections. Further studies should therefore apply other methods for determining the antibacterial activity of TEO vapours to assess the exact minimal concentration inhibiting bacterial growth.