BACKGROUND:　Lacticaseibacillus　paracasei,　widely　recognized　for　its　safety,　is　frequently　used　as　a　starter　culture　in　fermented　foods.　In　the　present　study,　the　differences　in　the　physicochemical　properties,　antioxidant　activities,　volatile　compounds　and　non-volatile　compounds　of　mango　juice　fermented　with　L.　paracasei　FJG2339　were　evaluated.　RESULTS:　The　results　displayed　that　L.　paracasei　FJG2339　significantly　reduced　the　total　sugar　content　of　mango　juice,　but　slightly　increased　the　contents　of　polyphenols　and　flavonoids.　Meanwhile,　the　ABTS　[i.e.　2,2＇-azino-bis(3-ethylbenzothiazoline-6-sulfonic　acid)],　DPPH　(i.e.　2,2-diphenyl-1-picrylhydrazyl)　and　OH　radical　scavenging　abilities　of　mango　juice　were　increased　by　28%,　29%　and　48%,　respectively,　after　L.　paracasei　FJG2339　fermentation.　Flavor　profiles　analysis　suggested　that　L.　paracasei　FJG2339　facilitated　the　production　of　acids,　alcohols　and　esters　in　mango　juice,　which　endow　it　with　a　distinct　aroma.　Untargeted　metabolomics　analysis　displayed　that　L.　paracasei　FJG2339　fermentation　significantly　shifted　207　non-volatile　compounds　(containing　123　up-regulated　non-volatile　substances　and　84　down-regulated　non-volatile　substances)　of　mango　juice,　which　are　mainly　involved　in　animo　acid　metabolism　(such　as　alanine,　aspartate　and　glutamate　metabolism,　tyrosine　metabolism,　tryptophan　metabolism,　phenylalanine　metabolism,　phenylalanine,　and　tyrosine　and　tryptophan　biosynthesis).　CONCLUSION:　These　results　indicate　that　L.　paracasei　FJG2339　fermentation　enhances　the　physicochemical　properties,　antioxidant　capacity　and　metabolic　profiles　of　mango　juices.　This　study　has　important　implications　for　the　application　of　fermentation　technology　of　fruit　juices.　(c)　2025　Society　of　Chemical　Industry.