Optimization of PHA Production at Laboratory Scale by using Different Carbohydrate Supplemented Davis Minimal Media

https://doi.org/10.5281/zenodo.19448887

Abstract

Background: PHAs (Polyhydroxyalkanoates) are biopolymers produced by certain microbes under specific growth conditions (limited essential nutrients including nitrogen, magnesium, phosphorus or oxygen but the surplus of carbon supply). Several studies have shown that the physical properties of these polymers, such as elasticity, stiffness, and strength, are similar to petroleum-based plastics. Additionally, they are biodegradable. This will reduce environmental pollution caused by plastic material. So, it is a need for time to identify such interesting bacteria from Pakistan. Pakistan is a well-known agricultural and food-producing country.  Conventional plastic causes environmental pollution problems, so we aim to produce green plastic (PHA) using different media and PHA producing microbes.

Methodology: In this research, PHA production was optimized using various wasted cheap carbohydrate-derived media like Dextrose, Glucose, Wheat Flour, Oatmeal Flour and Cassava at different PH ranges from 4 to 9 at a small scale. PH values ranging from 5 to 9 and using 1% Glucose as a carbon source.

Results: Different supplements produced varying levels of PHA output, with Dextrose producing the highest yield of 65% and Glucose producing the lowest yield of 42 %. Different incubation intervals ranging from 24 hours to 72 hours were used to test the optimal incubation time for each supplement. The results showed that the 48-hour incubation period provided the best/maximum yield for each supplement (Glucose, Dextrose, wheat flour, oat flour, and Cassava). Dextrose produced the highest PHA yield of all the supplements tested, at 66%, while wheat flour produced the lowest PHA yield, at 44 %.