Increasing the resistance of polyethersulfone ultrafiltration (PES UF) membrane to fouling remains a challenging endeavor when developing UF membrane. This paper concerns the incorporation of chitosan into PES UF membrane to produce low-fouling PES UF membrane. The membranes were produced by means of phase inversion with chitosan as an additive. https://parisnaturalfoodes.shop/product-category/elderberry-liquid/