Potentially Probiotic Lactobacillus Strains from Traditional Kurdish Cheese

Abstract

In this study, the probiotic potential of Lactobacillus strains isolated from traditional Kurdish cheese was investigated. The Lactobacillus strains were examined for resistance to gastric acidity and bile toxicity, antimicrobial activities, autoaggregation, coaggregation, hydrophobicity, adhesion to Caco-2 cells, and antibiotic susceptibility. The results showed that all strains tested tolerate acid gastric conditions (pH 2.0 and 3.0), and all of them were bile resistant (at 0.3 and 1% concentration). Although no antibacterial activity was detected in vitro assay for the treated (neutralized to pH 6.5 and treated with catalase) cell-free culture supernatant (CFCS) of strains, untreated CFCS showed strong antagonistic activity against two known pathogens bacteria. All strains exhibited a strong autoaggregating phenotype and manifested a high degree of coaggregation with pathogens. On the other hand, majority of studied strains were found sensitive to different antibiotics, such as ampicillin, penicillin, ciprofloxacin, chloramphenicol, erythromycin, rifampicin, and tetracycline, and were resistant to vancomycin and streptomycin. Finally, isolated strains showed good hydrophobicity and adherence to Caco-2 cell line, so they could be exploited for food manufacture.

Assessment of potentially probiotic properties of Lactobacillus strains isolated from chickens

“…Some isolates of chicken origin exhibited even 100% survival rate at pH of 2.0, while others showed no viability at those conditions (Garriaga et al 1998, Lee et al 2008, Bujnakova et al 2014. Hashemi et al (2014) described significantly lower viability of lactobacilli after 2 h of incubation at the pH 2 or in 0.3% of bile salt, but all evaluated bacteria were obtained from traditional kurdish cheese. It is well documented that lactobacilli isolated from GIT are able to tolerate low pH and bile salt, as compared to strains obtained from fermented food products (Ehrmann et al 2002, Koll et al 2008.…”

Probiotic Lactobacillus Strains from Traditional Iranian Cheeses

“…Table 14.1 shows a list of Lactobacillus strains isolated from traditional Iranian cheeses that are usually considered as probiotics. Tolerance to acid and bile, ability to adhere to the gastrointestinal mucosa, competitive exclusion of pathogens, and desirable antibiotic susceptibility patterns Tajabadi Ebrahimi et al, 2011;Hassanzadazar et al, 2012;Hashemi et al, 2014a) are some of the common criteria that have been used for the selection of these microorganisms as probiotic. Probiotic characteristics of these bacteria will be discussed below on the basis of the existing literature.…”

“…On the other hand, ingestion of probiotic strains with food or dairy products raises the pH in the stomach to 3.0 or higher (Iñiguez-Palomares et al, 2007). All these studies reported a growth delay of Lactobacillus strains in the presence of bile salts that were strain specific (Hassanzadazar et al, 2012;Hashemi et al, 2014a;Tofangsazan, 2014). Bile is an aqueous solution made up of bile acids, cholesterol, phospholipids, and the biliverdin, which gives the bile its yellow-green color.…”

“…Therefore, raising the pH improved the survival of probiotic organisms; this could possibly be a viable strategy for improving the survival of probiotics through the stomach environment. Bile tolerance of Lactobacillus strains isolated from Kurdish cheese was assessed by Hashemi et al (2014a). Bile plays an important role in lipid digestion; it emulsifies and solubilizes lipids and functions as biological detergent (Hofmann and Roda, 1984;Begley et al, 2006).…”

“…plantarum LP3 Kurdish cheese Hashemi et al (2014a) L. plantarum AF1 Kurdish cheese Hashemi et al (2014a) L. plantarum LU5 Kurdish cheese Hashemi et al (2014a) L. plantarum LS5 Kurdish cheese Hashemi et al (2014a) plantarum LP3 Kurdish cheese Hashemi et al (2014a) L. plantarum AF1 Kurdish cheese Hashemi et al (2014a) L. plantarum LU5 Kurdish cheese Hashemi et al (2014a) L. plantarum LS5 Kurdish cheese Hashemi et al (2014a) …”