Effect of phytoderivatives on the growth of homologous beneficial vaginal lactobacilli (BVL) strains and their compatibility for the design of phytobiotics for the vaginal tract health

Abstract

Background: Lactobacilli are the predominant bacteria in the vaginal tract, and while they are present, can prevent infectious situations, being used as probiotics for the health of the tract. Phytoderivatives are used historically to prevent or maintain the health of the tract, and is possible to combine both bioactives for novel vaginal formulas. The aim of this work was to study the effect of phytoderivatives (individual or combined extracts) on the growth of homologous vaginal lactic acid bacteria and their compatibility, to go further in the design of a combined pharmabiotic formula for the prevention or treatment of urogenital tract infections.Methods: the effect of phytocompounds approved by Pharcopoeias was evaluated on the growth of beneficial lactic acid bacteria previously isolated from the vaginal tract. Statistical methods, as CART, were applied to determine the stimulatory or inhibitory effect of the vegetal sources on bacterial growth by applying different methodology. Compatibility between phyto and lactobacilli was determined, and the phenolic compounds contents quantified, to define the optimal conditions for the formula design. Results: The BVL strains showing highest growth values with most of the phytoderivatives under study were L. gasseri CRL 1361, L. ga. CRL 1509 and L. ga. CRL 1263, and L. jensenii CRL 1333 and L. jen. CRL 1317, indicating the behavior is strain-dependent, and vegetable-compound-affected. The most adequate phytoderivatives were: Carica, Centella, Plantago, Uva ursi*, Zarzaparrila*, Cola de caballo, Echinaceae, Ortiga and Palo Azul.Conclusions: The BVL strains showing optimal resistance to the phytocompounds and compatibility with them were L. gasseri CRL 1320, 1307, 1509, L. salivarius CRL 1296 and L. rhamnosus CRL 1332 combined with Uva ursi*, Zarzaparrilla* and Echinaceae that will be used for the design of optimal phytobiotic formulas.

Functional and safety characterization of beneficial vaginal lactic acid bacteria for the design of vaginal hygiene products

“…C. albicans, St. agalactiae, S. aureus, E. coli) (De Gregorio et al, 2019;Juárez Tomás et al, 2005Leccese Terraf et al, 2012;Ocaña, Bru, et al, 1999;Ocaña, de Ruiz, et al, 1999b;Silva et al, 2021). This strain also evidenced biofilm formation and EPS production, being compatible with some phytoextracts and resistant to GIT conditions (Marchesi, Silva, Ficoseco, et al, 2020;, demonstrating a high resistance to osmotic stress, but not to high temperatures (Silva et al, 2019(Silva et al, , 2020. Referred to safety properties, L. rhamnosus CRL 1332 is resistant to erythromycin and does not express virulence enzymes.…”

“…Candida albicans , St. agalactiae , Klebsiella pneumoniae ), has a high hydrophobicity, and also is a biofilm former and EPS producer strain (De Gregorio et al, 2019; Juárez Tomás et al, 2011; Leccese Terraf et al, 2012; Ocaña, Bru, et al, 1999; Ocaña, de Ruiz, et al, 1999b). In addition, this strain is compatible with some phytoextracts (Marchesi, Silva, Wiese, & Nader‐Macías, 2020), resists the highest temperatures under thermal stress conditions (Silva et al, 2020) and expresses a moderate resistance to GIT conditions (Marchesi, Silva, Ficoseco, et al, 2020). Regarding the safety characteristics evaluated in this work, L. gasseri CRL 1320 showed resistance only to vancomycin and did not express virulence enzymes.…”

“…The microorganisms used in this study were 24 BVLAB strains isolated from healthy women and included in the Culture Collection of the Reference Center for Lactobacilli (CERELA) (Tucumán, Argentina). The strains were genotypically identified by our research group by 16S-RNA-DNA sequencing (Marchesi, Silva, Ficoseco, et al, 2020) described in previous works (Fosch et al, 2018). These strains were previously pre-selected by their beneficial probiotic properties and summarized with their recent taxonomy proposed by Zheng et al (2020) in Table S1.…”

“…Our research group isolated vaginal strains from healthy women in Tucumán, Argentina (Ocaña, Bru, et al, 1999). Most of these microorganisms were identified by phenotypic and genetic methods and some of their beneficial, functional and technological properties were evaluated through a wide variety of in vitro and in vivo (animals) tests, including a Phase I assay, which supported the first selection of beneficial lactobacilli (De Gregorio et al, 2016, 2019, 2020; Juárez Tomás et al, 2005, 2011; Leccese Terraf et al, 2012, 2014, 2016; Marchesi, Silva, Ficoseco, et al, 2020; Marchesi, Silva, Wiese, & Nader‐Macías, 2020; Ocaña et al, 2006; Ocaña, Bru, et al, 1999; Ocaña, de Ruiz, et al, 1999; Ocaña & Nader‐Macías, 2001, 2002; Silva et al, 2019, 2020; Vera Pingitore et al, 2009). The aim of this work was to complement the evaluation of functional and safety characterization of beneficial vaginal lactic acid bacteria (BVLAB) and select the most adequate strains to advance in the design of a probiotic formula that could reconstitute the VM and prevent urogenital tract infections (UGTIs) in women.…”

Probiotic Lactic Acid Bacteria for Vaginal Application. Optimization of Biomass Production and Freeze-Drying Conditions

“…Different VLB strains were previously isolated from healthy women in Tucumán, Argentina [20]. The strains showed appropriate surface and functional characteristics [21][22][23][24][25][26], such as safety [27] and resistance to osmotic stress, temperatures [28] and gastrointestinal tract conditions [29], to be used either as probiotics or combined with phytoderivatives [30]. Phase I assays were also performed to determine strains' safety in healthy women [31].…”