Abstract:To improve the antioxidant ability and key bioactive components of pine pollen， this study utilized three lactic acid bacteria （LAB） commonly employed in food processing： Lacticaseibacillus paracasei 6244，Lactiplantibacillus plantarum 21793， and Lactococcus lactis 23609 for fermentation. The changes in in vitro antioxidant activity （DPPH and ABTS+ radical scavenging capacity， ferric reducing antioxidant power）， total phenolic content （TPC）， and total flavonoid content （TFC） were investigated. Additionally， the phenolic composition of pine pollen before and after fermentation was systematically investigated using ultra performance liquid chromatography quadrupole-time of flight mass sectrometry and high performance liquid chromatography photodiode array detector. Results indicated that compared to water extraction， LAB fermentation enhanced the DPPH and ABTS+ radical scavenging capacity， ferric reducing antioxidant power， and total phenolic content of pine pollen were significantly increased by 156.31%， 136.87%， 46.63%， and 97.24%， respectively.All phenolic compounds showed marked increases after fermentation， with 4-hydroxybenzoic acid exhibiting the most pronounced change. The sum of all quantified phenolic compounds reached 903.00 μg/g dw following a 1-day fermentation with L. paracasei， representing an 11.80-fold increase over the water-extracted sample.Correlation analysis revealed that the elevated antioxidant activity was primarily attributed to the increased levels of protocatechuic acid， caffeoylquinic acid， p-coumaric acid， taxifolin， and naringenin. Principal component analysis further identified a 1-day fermentation with L. paracasei as the optimal strain-time combination.In conclusion， LAB fermentation effectively enhanced the bioactive components and antioxidant properties of pine pollen， providing a theoretical foundation for its application in functional products.