A non-dairy probiotic's (poi) influence on changing the gastrointestinal tract's microflora environment.

JUSTIFICATION Yogurt has been historically used to restore gut microflora adversely affected by antibiotic treatment. Certain fermented dairy products are probiotics; "live microorganisms which when administered in adequate amounts confer a health benefit to the host." Microorganisms in foods may benefit certain health conditions such as diarrhea, gastroenteritis, irritable bowel syndrome, inflammatory bowel disease, and cancer. A potential new probiotic from a Polynesian traditional food is poi; a starchy paste made from the corm of taro plants. OBJECTIVE The purpose of this study was to determine if consumption of poi, a potential non-dairy probiotic, altered the microflora in the gastrointestinal tract of healthy adults. METHODS A cross-over clinical study included 18 subjects (19-64 years of age) divided into a poi group (n = 10) and control group (n = 8). The study duration of 14 weeks consisted of a 2-week washout, 4-week treatment or control, a subsequent 2-week washout, cross-over of 4-week treatment or control, and a final 2-week washout. Subjects thus served as their own controls. While receiving the poi treatment, participants consumed fresh poi (1-2 days old) three times a day (130 g/meal or approximately 1/2 cup/meal); the control group did not. Both groups filled out 3-day dietary records to ensure compliance. Measurable outcomes included pre- and post-treatment microbiological fecal culture analyses. RESULTS We found no significant differences in total bacterial counts following a poi diet versus following a control diet, nor were significant differences found in counts of specific bacterial species. Lactococcus tends to be higher in poi when it is analyzed for specific bacteria, but the poi consumption in our study did not alter the mean concentration of individual bacterial species (log10 CFU/g wet feces) for Escherichia coli, Enterobacter, Klebsiella, Lactobacillus, Lactococcus, and Bifidobacterium. No significant differences in stool frequency or consistency were observed between the treatment and control group periods. CONCLUSION Poi consumption did not significantly alter total or individual bacterial counts in the human gastrointestinal tract. Further research might determine if "sour poi" (3-4 days old) has a greater affect than "fresh poi" (1-2 days old) as a potential probiotic, and a larger trial with longer diet durations may detect more subtle effects of poi consumption on bacterial counts.