Isolation and characterization of vaginal Lactobacillus spp. in dromedary camels (Camelus dromedarius): in vitro evaluation of probiotic potential of selected isolates

Abstract

Lactobacillus spp. is one of the beneficial lactic acid producing microbiota in the vagina, which is important for a healthy vaginal environment. However, little is known about vaginal Lactobacillus in dromedary camels (Camelus dromedarius). Therefore, this study aimed to isolate vaginal lactic acid bacteria (LAB) in dromedary camels and to study the probiotic potential of selected isolates. A total of 75 vaginal swabs were collected from pluriparous, non-pregnant, non-lactating dromedary camels. The LAB were isolated using deMan, Rogosa and Sharpe broth and agar media. Suspected LAB isolates were subjected to catalase testing and Gram staining and examined for indole production, nitrate reduction, hemolytic activity, cell surface hydrophobicity, auto- and coaggregation, antibacterial activity and characterized by 16S rRNA amplification and sequencing. Eighteen LABs were isolated from the 75 vaginal swabs. Among the 18 LAB isolates, six were Lactobacillus plantarum, eight were Lactobacillus fermentum, and four were Lactobacillus rhamnosus. None of the LAB isolates was hemolytic and only four LAB were H2O2 producing. The percentage of hydrophobicity ranged from 0% to 49.6%, 0% to 44.3% and 0% to 41.6% for hexadecane, xylene and toluene, respectively. All isolates showed higher (P < 0.05) autoaggregation after 24 h of incubation compared to 4 h. Furthermore, all LAB showed higher coaggregation (P < 0.05) and antimicrobial activity toward Staphylococcus aureus than to Escherichia coli. All LAB isolates were vancomycin resistant and sensitive to streptomycin, erythromycin, kanamycin and chloramphenicol. Only, three LAB isolates were resistant to tetracycline. The dromedary camel vaginal LAB isolates exhibited varying degrees of in vitro probiotic properties tested in this study and showed promising activity against the most common bacterial causes of endometritis in dromedary camels. Further investigation of the in vivo effect of these isolates is warranted.

Novel Probiotic Lactic Acid Bacteria Were Identified from Healthy Infant Feces and Exhibited Anti-Inflammatory Capacities

“…Notably, all selected strains exhibited strong inhibitory effects against E. faecalis E27. As reported, due to the exceptional multidrug resistance, most isolates of E. faecalis have caused clinical infections that are often hard to treat [ 41 ]. However, the antibiotic resistance of E. faecalis selected in our study hasn’t been assayed.…”

The Use of Probiotics for Management and Improvement of Reproductive Eubiosis and Function

“…El-Deeb and co-workers [66] isolated 18 Lactobacillus species from the vaginas of dromedary camels, (belonging to Lactobacillus plantarum, fermentum and rhamnosus) with potential probiotic properties. These bacterial species also exhibit phenotypical resistance to vancomycin-resistant strains and sensitivity to streptomycin, erythromycin, kanamycin, and chloramphenicol [66].…”

“…El-Deeb and co-workers [66] isolated 18 Lactobacillus species from the vaginas of dromedary camels, (belonging to Lactobacillus plantarum, fermentum and rhamnosus) with potential probiotic properties. These bacterial species also exhibit phenotypical resistance to vancomycin-resistant strains and sensitivity to streptomycin, erythromycin, kanamycin, and chloramphenicol [66]. In fact, however, this criterion may raise some fear toward the antimicrobial resistance issue; the different mechanism of antimicrobial resistance of these strains compared to other bacteria such as Enterococci may preclude this fear, as the antimicrobial resistance of these strains is attributed to the synthesis of a modified cell-wall peptidoglycan precursor and is different from the transferable mechanism observed for other bacteria [50].…”

“…In addition, vaginal isolates of dromedary camels (Camelus dromedarius) have been found to contain Lactobacillus species belonging to Lactobacillus plantarum, Lactobacillus fermentum, and Lactobacillus rhamnosus strains with potential probiotic properties. These bacterial species showed strong antimicrobial activity against Staphylococcus aureus, which is considered as one of the most common bacterial causes of endometritis in dromedary camels and other animal species [66].…”