It is an interesting article describing the relationship between the time of Lactocbacillus sp. acquisition from human breast milk 1,3 and 6 months after childbirth and kinetic parameters of bacteria growth as lag phase and the time needed to reach the OD 600nm of 0.5. Results of Authors show that Lactobacillus sp. isolated from samples obtained 1 month after childbirth have longest lag phase and most quickly achieve the OD 600 nm of 0.5. Analysis of regression models showed that growth rate decreased stepwise in older human milk samples and was slowest in material obtained 6 months after childbirth. Obtained results may have implications in future research more detailly describing properties of bacteria that settle in the newborn baby intestine. I suggest that following improvements should be done before publication: 1. Extensive English language and misspelling corrections (Rnase etc) - if possible by native English speaker. 2. The fact that milk was obtained 1,3 or 6 months after childbirth should be clearly stressed in material and method section 2.1. 3. Some doubts may be related to the fact that samples isolated milk 1 and 3 months after childbirth are represented mostly by L. plantarum and sample obtained from material after 6 months was represented mainly by L. pentosus. However I understand that the composition of bacteria in human breast milk may change over time and results obtained of Authors still suggest interesting relationship between lag phase duration, growth rate and time of sample acquisition (1,3 or 6 months). 4. I suggested also improvement of introduction section which is described in my opinion sent to Authors.

Comments for Authors:

Comment 1: Extensive editing of English language is required- if possible performed by native English speaker. Comment 2: Introduction could be improved by including citation of a review article - Bertrand, J of Bacteriology, 2019, 201, e00697-18. Also novel methods of lag phase determination as Raman spectroscopy could be shortly presented (Ren et al., Microbial Cell Factories, 2017, 16, 223.) Comment 3: Paragraph 2.2- Rnase- should be corrected to RNase.