eng Enviro Research Publishers Current Research in Nutrition and Food Science Journal 2347-467X 2322-0007 2024-12-15 12 3 1354 1365 10.12944/CRNFSJ.12.3.29 21126 article Maha Rehman 1 Rehan Naeem 1 Sunanda Biswas 2 Maheen Sohail 1 Sadeeq Khan 1 Muhammad Arif 1 Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology, Kohat, Khyber Pakhtunkhwa, Pakistan. Department of Food and Nutrition, Acharya Prafulla Chandra College, Kolkata, India Department of Clinical Nutrition, Nur International University, Lahore, Pakistan Department of Microbiology, University of Agriculture, Faisalabad, Pakistan Folate, an essential nutrient crucial for DNA synthesis, cell division, and fetal neural tubedevelopment, remains a global health concern due to deficiencies in certain populations. Toaddress this issue, we investigated the synergistic interaction between Spirulina, a nutrient-rich microalga, and two strains of folic acid-producing bacteria, Bacillus subtilis-1 and Bacillus subtilis-2, to enhance folate production. Spirulinahas high nutritional content, combined with the folate production capabilities of the selected bacteria, offered a promising opportunity for sustainable folate synthesis. In this study, Spirulinaand the two strains of Bacillus subtilis were cultured separately to optimize growth conditions for each organism. Co-culture experiments were then conducted, combining Spirulina with Bacillus subtilis-1 and also Bacillus subtilis-2, to investigate their collective potential for folate production. The specific growth rates of both Spirulinaand the bacteria were measured individually and in combination using spectrophotometric methods, and their dry weights were determined to assess biomass productivity. Folate quantification in the microalgal-bacterial cultures was performed using a spectrophotometric analysis based on the phosphate buffer extraction method. This method facilitated the measurement of folate content investigated the impact of the symbiotic relationship between Spirulina and bacteria, particularly in terms of enhancing vitamin B₁₂ acquisition and its impact on folate synthesis. Our results revealed a synergistic enhancement in folate production at the exponential growth phase of Bacillus subtilis-1 and Bacillus subtilis-2 co-culture. The synergistic relationship between Spirulina and Bacillus subtilis-1, as well as Bacillus subtilis-2, is manifested in elevated folate synthesis, highlighting the significant impact of microbial cooperation on nutrient production. Additionally, we observed fluctuations in folate production at the stationary phase, highlighting the subtle equilibrium achieved through symbiotic interactions. These findings shed light on the potential of harnessing the synergistic potential of microorganisms for sustainable folate synthesis. This research advances co-culturing methods to optimize folate production, tackling global folate deficiency challenges and fostering innovative, sustainable nutritional solutions. https://www.foodandnutritionjournal.org/volume12number3/synergistic-interaction-of-spirulina-sp-and-folic-acid-producing-bacteria-for-folate-production/ Co-cultivation Folic acid Folate production Folic acid-producing bacteria Growth dynamics Spirulina Synergistic interaction