To overcome the disadvantages of pu’er, we developed a post-fermentation oolong tea high in GA by a 2-week fermentation process mediated by A. sojae, which preserves the anti-DNA methylation function of GA, showing stronger reduction effects on the genomic 5mC content in lung cancer cells than oolong tea and even the well-known DNMT inhibitor 5azaC (Figure 5A). This evidence concerns the gene DNMT1 and lung carcinoma.