hey nandita,

M.S.c microbiology and M.S.c biotechnology are two different course however in terms of topic they do resemble a little to eachother,  in biotechnology what you will study is vaacine development , brewing to plant breeding , diagnostics and preganancy testing whereas in microbiology about what you are going to study is microbes, bacteria , viruses, protozoa , microalgae etc.

hope it helped you!