Carbohydrate is the most abundant biomolecule on earth. Carbohydrate is organic compound synthesized in the chlorophyll-containing cells of some bacteria, algae and green plants, during photosynthesis. Certain photoautotrophic bacteria, e.g. Green sulphur bacteria and purple sulphur bacteria contain pigments like Chlorophyll and Bacteriochlorophyll, respectively that helps them in photosynthesis. During photosynthesis, carbon dioxide reduced into carbohydrates by water and oxygen is liberated.