The effect of Lactobacillus brevis KB290 against irritable bowel syndrome: a placebo-controlled double-blind crossover trial

Abstract

BackgroundIrritable bowel syndrome (IBS) is a functional disorder of the digestive tract that causes chronic abdominal symptoms. We evaluated the effects of Lactobacillus brevis KB290 (KB290), which has been demonstrated to be effective at improving bowel movements and the composition of intestinal microflora, on IBS symptoms.MethodsWe performed a placebo control double-blind cross matched trial. Thirty-five males and females (aged 6 years and above) who had been diagnosed with IBS according to the Rome III criteria were divided into 2 groups, and after a 4-week pre-trial observation period, they were administered test capsules containing KB290 or placebo for 4 weeks (consumption period I). Then, the capsule administration was suspended for 4 weeks in both groups (washout period), before the opposite capsules were administered for a further 4 weeks (consumption period II). Fecal samples were collected on the first day of the pre-consumption observation period, the last day of consumption period I, the last day of the washout period, and the last day of consumption period II. In addition, the subjects’ IBS symptoms and quality of life (QOL) and any adverse events that they experienced were evaluated.ResultsNo significant difference in IBS symptoms was noted among the various periods. However, the mean QOL scores were improved during the test capsule consumption.The frequencies of watery and mushy feces were significantly lower in the test capsule consumption period than during the pre-consumption observation period, and the frequency of abdominal pain was significantly reduced in the test capsule consumption period compared with the other periods.The frequency of the genus Bifidobacterium was significantly higher, and that of the genus Clostridium was significantly lower, after the test capsule consumption than after the placebo consumption. The frequencies of the genera Lactobacillus, Bacteroides, and Enterococcus were also investigated, but no differences in their frequencies were detected between the placebo and test capsule consumption periods.ConclusionsProbiotics, the safety of which has been established, are used widely in various foods and can now be purchased readily. The results of the present study suggest that KB290 is useful for early intervention in IBS.

Probiotic Therapy of the Irritable Bowel Syndrome: Why Is the Evidence Still Poor and What Can Be Done About It?

“…37,52,56, Four studies employed a cross-over design, 52,56,90,105 which is frequently used for motivational purposes (patients are easier to recruit when they are offered an effective treatment, at least for a part of the trial). However, they are difficult to evaluate since the assumption that the data in both periods is equal and can be merged may be distorted by unblinding and conditioning effects.…”

“…Other lactobacilli strains were used only in single trials, such as Lactobacillus brevi, 90 L. acidophilus, 56,100 Lactobacillus reuteri, 103 Lactobacillus rhamnosus GG, 107 and Lactobacillus casei (CLR35).…”

Growth characteristics of Lactobacillus brevis KB290 in the presence of bile

“…We recently showed that some plant-derived strains have high bile tolerance [19]. Lactobacillus brevis KB290 isolated from suguki, a traditional fermented vegetable product from the Kyoto region of Japan, has several probiotic activities, including stimulation of immune function [7,21,38] and improvement of gut health [27,29]. Strain KB290 can tolerate artificial digestive juice and bile salts because of its cell-bound exopolysaccharide (EPS) [34] and other factors.…”

Genomic Analysis by Deep Sequencing of the Probiotic Lactobacillus brevis KB290 Harboring Nine Plasmids Reveals Genomic Stability

“…KB290 has been found to tolerate gastrointestinal juices, stimulate immune function [13]–[15], and improve gut health [13]–[15]. Moreover, KB290 has a strong tendency to aggregate in broth medium, which may be a desirable property that allows for co-aggregation with pathogenic bacteria, and it colonizes and immunomodulates colonic mucosa [16]–[21].…”