Physiological Characteristics and Production of Folic Acid of Lactobacillus plantarum JA71 Isolated from Jeotgal, a Traditional Korean Fermented Seafood

Abstract

Folic acid, one of the B group of vitamins, is an essential substance for maintaining the functions of the nervous system, and is also known to decrease the level of homocysteine in plasma. Homocysteine influences the lowering of the cognitive function in humans, and especially in elderly people. In order to determine the strains with a strong capacity to produce folic acid, 190 bacteria were isolated from various kinds of jeotgal and chungkuk-jang. In our test experiment, JA71 was found to contain 9.03μg/mL of folic acid after 24 h of incubation in an MRS broth. This showed that JA71 has the highest folic acid production ability compared to the other lactic acid bacteria that were isolated. JA71 was identified as Lactobacillus plantarum by the result of API carbohydrate fermentation pattern and 16s rDNA sequence. JA71 was investigated for its physiological characteristics. The optimum growth temperature of JA71 was 37℃, and the cultures took 12 h to reach pH 4.4. JA71 proved more sensitive to bacitracin when compared with fifteen different antibiotics, and showed most resistance to neomycin and vancomycin. Moreover, it was comparatively tolerant of bile juice and acid, and displayed resistance to Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus with restraint rates of 60.4%, 96.7%, and 76.2%, respectively. These results demonstrate that JA71 could be an excellent strain for application to functional products.

Lactic acid fermentation as a tool for increasing the folate content of foods

“…Table 5 shows that folate may also be consumed or produced in different culture media, and that this is highly variable and strain dependent. L. plantarum JA71 produced the highest concentration of folate in MRS medium (9,030 ng/mL) (Park et al, 2014) and L. plantarum SM39 produced 4,413 ng/mL in a supplemented whey permeate medium (Hugenschmidt et al, 2011). Folate production also depends on growth kinetics and on the culture conditions.…”

“…NC: Not Calculated *offal includes folate-rich products such as liver and kidney, as well as products with a much lower folate content such as heart and brain. MRS (n=2) -10 to 9030 (Hugenschmidt et al, 2011;Padalino et al, 2012;Park et al, 2014) SWP (n=28) 0 to 4413 (Hugenschmidt et al, 2010(Hugenschmidt et al, , 2011 L. reuteri CDM (n=1) 59 (Santos et al, 2008) SWP (n=3) 0 to 125* (Hugenschmidt et al, 2010) L. rhamnosus SWP (n=1) -10 to 0* (Hugenschmidt et al, 2010) YPD (n=3) <0* (Herranen et al, 2010) L. sakei FFM (n=2) 101 to 107 (Masuda et al, 2012) Lc. lactis M17 (n=16) 57 to 291 (Sybesma et al, 2003) YPD (n=2) <0* (Herranen et al, 2010) Leuconostoc lactis MRS (n=1) 45 (Sybesma et al, 2003) Ln.…”