In vitro evaluation of effect watermelon and melon seeds on the growth of probiotic bacteria

In this study, the effect of melon and watermelon seed on the development of Bifidobacterium animalis subsp. lactis, Bifidobacterium longum subsp. infantis, Bifidobacterium bifidum, Lactobacillus acidophilus, Lactobacillus casei in vitro fermentation medium was investigated. Carbohydrate-free TPY broth for Bifidobacterium spp. and carbohydrate-free MRS broth for Lactobacillus spp. were used as basal growth media. The highest pH value was determined in the negative control sample (6.99), while the lowest pH value (3.54) was found in the medium containing glucose. The highest OD value (2.281) was determined in the sample containing glucose. During the fermentation the highest number of microorganisms (10.30 cfu/mL) was determined in the medium containing watermelon seed. Among the substrate types, the highest PAS value (1.54) was determined in the medium containing watermelon seed. The amounts of glucose (8.69 g/L), galactose (21.77 g/L), fructose (21.19 g/L) and sucrose (13.42 g(L) were stated to be highest in the medium inoculated with Lb. acidophilus. The amount of xylose (3.46 g/L) was determined to be the highest in the medium inoculated with Lb. casei. The amounts of acetic (89.722 ppm), propionic (4.778 ppm) ve butyric acid (1.303 ppm) were determined to be highest in the medium inoculated with Lb. acidophilus. The amount of lactic acid (1594.280 ppm) was determined to be the highest in the medium inoculated with Lb. casei. It was stated that whole watermelon and melon seed had a positive effect on the growth/activity probiotics. The results demonstrated that these substrates have potential prebiotic properties.