Stable-isotope examining (SIP) is a strategy in microbial nature for following transitions of supplements in biogeochemical cycling by microorganisms. A substrate is enhanced with a heavier stable isotope that is devoured by the creatures to be considered. A substrate is advanced with a heavier stable isotope that is devoured by the living beings to be contemplated. Biomarkers with the heavier isotopes fused into them can be isolated from biomarkers containing the more normally plenteous lighter isotope by isopycnic centrifugation. For instance, 13CO2 can be utilized to discover which living beings are effectively photosynthesizing or devouring new photosynthate. As the biomarker, DNA with 13C is then isolated from DNA with 12C by centrifugation. Sequencing the DNA recognizes which life forms were devouring existing starches and which were utilizing sugars all the more as of late created from photosynthesis. At the point when DNA is the biomarker, SIP can be performed utilizing isotopically marked C, H, O, or N, however 13C is utilized regularly. A more fragile DNA light thickness move is seen when 15N-versus 13C-marked substrates were utilized in unadulterated culture. Alternately, an extremely solid light thickness move was seen when the two marks were utilized.