Aqueous two-phase flotation for primary recovery of bacteriocin-like inhibitory substance (BLIS) from Pediococcus acidilactici Kp10

Abstract

An aqueous two-phase flotation (ATPF) system based on polyethylene glycol (PEG) and sodium citrate (NaNO3C6H5O7·2H2O) was considered for primary recovery of bacteriocin-like inhibitory substance (BLIS) from Pediococcus acidilactici Kp10. The effects of ATPF parameters namely phase composition, tie-line length (TLL), volume ratio between the two phases (VR), amount of crude load (CL), pH, nitrogen gas flow rate (FR) and flotation time (FT) on the performance of recovery were evaluated. BLIS was mainly concentrated into the upper PEG-rich phase in all systems tested so far. The optimum conditions for BLIS purification, which composed of PEG 8000/sodium citrate, were: TLL of 42.6, VR of 0.4, CL of 22% (w/w), pH 7, average FT of 30min and FR of 20mL/min. BLIS was partially purified up to 5.9-fold with a separation efficiency of 99% under this optimal conditions. A maximum yield of BLIS activity of about 70.3% was recovered in the PEG phase. The BLIS from the top phase was successfully recovered with a single band in SDS-gel with molecular weight of about 10-15kDa. ATPF was found to be an effective technique for the recovery of BLIS from the fermentation broth of P. acidilactici Kp10.

Bacteriocin partitioning from a clarified fermentation broth of Lactobacillus plantarum ST16Pa in aqueous two-phase systems with sodium sulfate and choline-based salts as additives

“…Although a few studies using bacteriocin partitioning/recovery using PEG/salt-based ATPSs [26][27][28][29][30], and with an aqueous two-phase micellar system (ATPMS) [31,32], have been evaluated, PEG/NaPA systems composed of inorganic salts or choline-based salts have not been proposed before. In this context, and based on the advantages mentioned above, the present study investigated a PEG/NaPA based ATPS with Na 2 SO 4 or choline chloride ([Ch]Cl) as additives to extract bacteriocin from the fermented broth of Lactobacillus plantarum ST16Pa.…”

Aqueous Two‐Phase Systems at Large Scale: Challenges and Opportunities

“…In ATPF, operation process parameters are designed to only move the product of interest to the top phase. ATPF has been successful to separate bromelain, cyclodextringlycosyltransferase, flavonol glycosides, and bacteriocin‐like inhibitory substance . Moreover, ATPF has been employed at pilot‐scales for the purification of lipase .…”

Biotechnological production and application of antimicrobial biomolecules by <i>Lactobacillus plantarum</i> in milk whey

“…Then, 20 µL of the CFS was spotted onto the agar surface. A period of 3 h was allowed for the diffusion of the supernatant at room temperature and after the plates were incubated at 30°C for 24 h. Subsequently, the inhibition halos were measured in four directions by a digital caliper gauge (Lee Tools, model 684132) and the antimicrobial activity of bacteriocin (A Bact ), defined in arbitrary units (AU), was calculated based on Sidek et al (2016). The equation is represented as follows:…”

“…Remarkably, IL-based ATPPS have been shown to overcome some of the main limitations of typical polymer-polymer or polymer-salt systems since it is possible to tailor the properties and affinities of the IL-rich phase by adequately choosing the IL chemical structure (Pereira, Rebelo, Rogers, Coutinho, & Freire, 2013). In general, IL-based ATPPS have shown a better extractive performance compared to traditional polymer based ATPPS (Freire et al, 2012) Although few studies with bacteriocin partitioning/recovery using PEG/salts based ATPPS (Abbasiliasi et al, 2014;Lappe, Anna, & Brandelli, 2012;Li, Bai, Li, Cai, & Ouyang 2001;Li, Ouyang, & Bai, 2000;Sidek et al, 2016) and with aqueous two-phase micellar system (ATPMS) 2013) have already been evaluated, PEG/NaPA systems composed of salts or ILs have never been proposed before. In this context and based on the advantages above mentioned, our group investigated PEG/NaPA based ATPPS with the ionic liquid choline chloride ([Ch]Cl) to extract bacteriocin from fermented broth of Lactobacillus plantarum ST16Pa.…”

“…Next, 20 µL of the CFS was pipetted onto the agar surface. A period of 3 h was allowed for the diffusion of the supernatant at room temperature and after that, the plates were incubated at 30 °C for 24 h. Then, the inhibition halos were measured using a digital caliper and the antimicrobial activity was defined in AUs, which represent the area of the inhibition halos per unit of volume in mL (mm 2 /mL), calculated by the procedure adapted from the methodology presented bySidek et al (2016).2.9. BLIS biopreservative efficiency in fresh chicken breast filletsTo investigate the biopreservative efficiency of CFS against the growth of bioindicator strain E. faecium 711, fresh chicken breast fillets (at 24 h post mortem and individually aged on ice) were purchased in a local market, and transported to the laboratory in a refrigerated thermal box (~4 °C).…”