Hayek, Saeed AShahbazi, AboghasemWorku, MulumebetIbrahim, Salam A2015-09-052015-09-052014-05Hayek Saeed A, Shahbazi Aboghasem, Worku Mulumebet, Ibrahim Salam A. Enzymatic Activity of Lactobacillus Grown in a Sweet Potato Base Medium. British Microbiology Research Journal. 2014 May; 4(5): 509-522.http://imsear.searo.who.int/handle/123456789/163127Aim: To study the impact of sweet potatoes on α-glucosidase, β-glucosidase, acid phosphatase, and phytase activity of Lactobacillus. Study Design: Enzymatic activity of seven strains of Lactobacillus grown in a sweet potato medium (SPM) was determined and compared to the standard lactobacilli MRS. Strains having the highest enzymatic activity were further enhanced by metal ions. Place and Duration of Study: Food Microbiology and Biotechnology Laboratory, North Carolina A&T State University, Greensboro, NC, USA, between September 2012 and May 2013. Methodology: Lactobacillus strains were grown in SPM and MRS at 37ºC for 16 h. At the end of incubation, bacterial population (log CFU/mL) was determined by plating and enzymatic activity was determined spectrophotometrically using the corresponding substrate. Results: Lactobacillus strains continue to grow in SPM and MRS and reached averages of 10.98±0.49 and 10.92±0.55 log CFU/mL respectively. Growth of Lactobacillus strains in SPM led to higher β-glucosidase, acid phosphatase, and phytase activity than MRS. Strains of L. reuteri (CF2-7F and SD2112) grown in SPM showed the highest acid phosphatase (15.84±1.05 and 20.56±1.49 Ph U/mL), and phytase (0.66±0.14 and 0.65±0.11 Ph U/mL) respectively. The highest β-glucosidase (36.04±3.16 Glu U/mL) activity was obtained from L. delbrueckii subsp. bulgaricus SR35 grown in SPM. In addition, acid phosphatase and phytase produced by L. reuteri CF2-7F growing in SPM were further increased by the addition of Mn2+ (70.1 and 41.8%) or Mg2+ (94.7 and 20.9%) respectively. β-glucosidase activity of L. reuteri was increased in a range of 4.1 to 130.6% due to the addition of metal ions. Conclusion: Components in sweet potatoes could increase enzymatic activity of Lactobacillus and the addition of metal ions could further produce an enhanced level of these enzymes.enSweet potato mediumLactobacillusenzymatic activitymetal ions and L. reuteriArticle