ABSTRACT

Argemone ochroleuca Sweet, Brit. Fl. Gard. Ser.1 3(2): pl. 242 (1828) of the family Papaveraceae is reported here for the first time from Libya. This species is native to Mexico. Flowering specimens of A. ochroleuca were collected from the region Ariggiba (26°35’11.8”N 13°29’24.8”E), 110 km southwest of the city of Sabha, which lies about 700 km south of Tripoli. It is presented with updated nomenclature, taxonomic description, geographical distribution, key to genera, location in Libya, and colour photographs taken in the field. The voucher specimens are deposited in the Herbarium of Botany Department (ULT), University of Tripoli, Libya.

A new record for Leptadenia arborea (Forssk.) Schweinf. is reported for the first time in the flora of Libya. This species was collected from Ariggiba region (110 km southwest Sabha city). A full description and habitat information on the plant are provided. A brief discussion about the most important traits of this species is presented.

Abstract

For the first time in Libyan flora, a new record for Boerhavia repens L is recorded. This widespread wild weed was collected from the Ariggiba region (110 km west-south Sabha city). A full description, habitat information, distribution map, and distribution data are provided to facilitate further identification and future detection. A brief discussion about the most important threats this species poses is presented.

Clostridioides difficile is widely recognised as one of the most common causes of healthcare-associated C. difficile infections due to the ability of spores to survive for prolonged periods in the hospital environment. This study aimed to evaluate the efficacy of UV-C 254 nm light in the inactivation of the spores of different C. difficile ribotypes on brain heart infusion (BHI) agar plates or in phosphate-buffered saline (PBS) with varying spore densities. Furthermore, the effectiveness of a sporicidal surface disinfectant against C. difficile spores was determined on different surfaces. Spore suspensions of different C. difficile strains in the range of 10⁵–10⁷ colony-forming units (CFUs) mL⁻¹ were inoculated on BHI agar plates or in PBS and exposed to UV-C light for up to 30 min. Additionally, a spore suspension of 10³–10⁵ CFUs was spread over a 1 cm² test area on different surfaces, and sporicidal surface wipes were used according to the manufacturer’s instructions. The findings demonstrated that spores of C. difficile ribotypes exhibited a complete reduction in log₁₀ CFU on BHI agar plates and PBS following 20 min of exposure to a UV-C dose of 2208 mJ cm⁻². The surface wipes with sporicidal properties demonstrated efficacy in reducing the number of C. difficile spores on the Formica, stainless steel, and plastic surfaces by 2.03–3.53 log₁₀. The present study demonstrates that moist surfaces or liquids can enhance the efficacy of UV-C treatment in reducing C. difficile spores. This approach may be applicable to the surfaces of healthcare facilities and to water disinfection systems.

Clostridioides difficile is an important human pathogen causing antibiotic-associated diarrhoea worldwide. Besides using antibiotics for treatment, the interest in bacteriophages as an alternative therapeutic option has increased. Prophage abundance and genetic diversity are well-documented in clinical strains, but the carriage of prophages in environmental strains of C. difficile has not yet been explored. Thus, the prevalence and genetic diversity of integrated prophages in the genomes of 166 environmental C. difficile isolates were identified. In addition, the clustered regularly interspaced short palindromic repeats (CRISPR)-Cas systems were determined in the genomes of prophage regions. Predicted prophages and CRISPR-Cas systems were identified by using the PHASTER web server and CRISPRCasFinder, respectively. Phylogenetic relationships among predicated prophages were also constructed based on phage-related genes, terminase large (TerL) subunits and LysM. Among 372 intact prophages, the predominant prophages were phiCDHM1, phiCDHM19, phiMMP01, phiCD506, phiCD27, phiCD211, phiMMP03, and phiC2, followed by phiMMP02, phiCDKM9, phiCD6356, phiCDKM15, and phiCD505. Two newly discovered siphoviruses, phiSM101- and phivB_CpeS-CP51-like Clostridium phages, were identified in two C. difficile genomes. Most prophages were found in sequence types (STs) ST11, ST3, ST8, ST109, and ST2, followed by ST6, ST17, ST4, ST5, ST44, and ST58. An obvious correlation was found between prophage types and STs/ribotypes. Most predicated prophages carry CRISPR arrays. Some prophages carry several gene products, such as accessory gene regulator (Agr), putative spore protease, and abortive infection (Abi) systems. This study shows that prophage carriage, along with genetic diversity and their CRISPR arrays, may play a role in the biology, lifestyle, and fitness of their host strains.

Clostridioides difficile is the most important pathogen causing antimicrobial-associated diarrhea and has recently been recognized as a cause of community-associated C. difficile infection (CA-CDI). This study aimed to characterize virulence factors, antimicrobial resistance (AMR), ribotype (RT) distribution and genetic relationship of C. difficile isolates from diverse fecally contaminated environmental sources. C. difficile isolates were recovered from different environmental samples in Northern Germany. Antimicrobial susceptibility testing was determined by E-test or disk diffusion method. Toxin genes (tcdA and tcdB), genes coding for binary toxins (cdtAB) and ribotyping were determined by PCR. Furthermore, 166 isolates were subjected to whole genome sequencing (WGS) for core genome multi-locus sequence typing (cgMLST) and extraction of AMR and virulence-encoding genes. Eighty-nine percent (148/166) of isolates were toxigenic, and 51% (76/148) were positive for cdtAB. Eighteen isolates (11%) were non-toxigenic. Thirty distinct RTs were identified. The most common RTs were RT127, RT126, RT001, RT078, and RT014. MLST identified 32 different sequence types (ST). The dominant STs were ST11, followed by ST2, ST3, and ST109. All isolates were susceptible to vancomycin and metronidazole and displayed a variable rate of resistance to moxifloxacin (14%), clarithromycin (26%) and rifampicin (2%). AMR genes, such as gyrA/B, bla_CDD-1/2, aph(3′)-llla-sat-4-ant(6)-la cassette, ermB, tet(M), tet(40), and tetA/B(P), conferring resistance toward fluoroquinolone, beta-lactam, aminoglycoside, macrolide and tetracycline antimicrobials, were found in 166, 137, 29, 32, 21, 72, 17, and 9 isolates, respectively. Eleven “hypervirulent” RT078 strains were detected, and several isolates belonged to RTs (i.e., RT127, RT126, RT023, RT017, RT001, RT014, RT020, and RT106) associated with CA-CDI, indicating possible transmission between humans and environmental sources pointing out to a zoonotic potential.

The goal of this study was to investigate the vegetation composition and structure of the Al-Orban area in Gharyan district, Libya over two continues growing seasons from the first of January 2020 to the first of Jaunary 2022. During this period, a total of 309 plant species were identified and collected in the field. These species belonged to 43 families, with 39 families of dicotyledons and 4 families of monocotyledons. The most dominant family was Asteraceae with 60 species, followed by Fabaceae with 32 species, Poaceae with 33 species, and Brassicaceae with 35 species. The most dominant genera were Plantago and Euphorbia, each represented by 6 species, followed by Erodium and Chenopodiun with 5 species each, and Astragalus, Centaurea, Rumex, Concolvulus, and Stipa each represented by 4 species. Life-form spectrum analysis indicated that Therophytes were the most predominant with 189 species, followed by Hemicryptophytes with 47 species, and geophytes with 40 species. Furthermore, chorotype spectrum analysis showed the dominance of Mediterranean species with 128 species, followed by Mediterranean/Iranian-Turanian with 66 species. These findings provide valuable insight into the plant diversity and distribution in the Al-Orban area of Gharyan district, Libya.

Clostridioides difficile (C. difficile) is the most common pathogen causing antibiotic-associated intestinal diseases in humans and some animal species, but it can also be present in various environments outside hospitals. Thus, the objective of this study was to investigate the presence and the characteristics of toxin-encoding genes and antimicrobial resistance of C. difficile isolates from different environmental sources. C. difficile was found in 32 out of 81 samples (39.50%) after selective enrichment of spore-forming bacteria and in 45 samples (55.56%) using a TaqMan-based qPCR assay. A total of 169 C. difficile isolates were recovered from those 32 C. difficile-positive environmental samples. The majority of environmental C. difficile isolates were toxigenic, with many (88.75%) positive for tcdA and tcdB. Seventy-four isolates (43.78%) were positive for binary toxins, cdtA and cdtB, and 19 isolates were non-toxigenic. All the environmental C. difficile isolates were susceptible to vancomycin and metronidazole, and most isolates were resistant to ciprofloxacin (66.86%) and clindamycin (46.15%), followed by moxifloxacin (13.02%) and tetracycline (4.73%). Seventy-five isolates (44.38%) showed resistance to at least two of the tested antimicrobials. C. difficile strains are commonly present in various environmental sources contaminated by feces and could be a potential source of community-associated C. difficile infections.

Soil fertilization with wastewater treatment plant (WWTP) biosolids is associated with the introduction of resistance genes (RGs), mobile genetic elements (MGEs) and potentially selective pollutants (antibiotics, heavy metals, disinfectants) into soil. Not much data are available on the parallel analysis of biosolid pollutant contents, RG/MGE abundances and microbial community composition. In the present study, DNA extracted from biosolids taken at 12 WWTPs (two large-scale, six middle-scale and four small-scale plants) was used to determine the abundance of RGs and MGEs via quantitative real-time PCR and the bacterial and archaeal community composition was assessed by 16S rRNA gene amplicon sequencing. Concentrations of heavy metals, antibiotics, the biocides triclosan, triclocarban and quaternary ammonium compounds (QACs) were measured. Strong and significant correlations were revealed between several target genes and concentrations of Cu, Zn, triclosan, several antibiotics and QACs. Interestingly, the size of the sewage treatment plant (inhabitant equivalents) was negatively correlated with antibiotic concentrations, RGs and MGEs abundances and had little influence on the load of metals and QACs or the microbial community composition. Biosolids from WWTPs with anaerobic treatment and hospitals in their catchment area were associated with a higher abundance of potential opportunistic pathogens and higher concentrations of QACs.