In vitro studies on the immunomodulatory effects of fulvic acid extract from palm oil empty fruit bunch (OPEFB)Firda Dimarwanita, Silmi Mariya, Fitria Nur Annisa Dewi, Silva Latisya, Yora Faramitha and Didiek Hadjar GoenadiBIO Web Conf., 154 (2025) 02002DOI: https://doi.org/10.1051/bioconf/202515402002