Institute of Sciences of Food Production, National Research Council, Via G. Celoria 2, Milan, 20133, Italy.
FEMS Microbiol Lett. 2020 May 1;367(9). doi: 10.1093/femsle/fnaa059.
Lactic acid bacteria (LAB) can be used to increase the folate in foods by in situ fortification. Seventy LAB were screened for their ability to produce folate during growth in de Man, Rogosa and Sharpe/M17 broth. Lactobacillus casei, Lactobacillus plantarum, Lactobacillus paracasei subsp. paracasei, Lactobacillus rhamnosus, Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, Lactococcus lactis subsp. lactis, Enterococcus faecium and Enterococcus lactis were able to synthetize folates in the medium, even if to a different extent. The 47 folate-producing strains were further analyzed by microbiological assay, for total, extra and intracellular folate. Enterococcus faecium VC223 and E. lactis BT161 were able to produce in cultural medium 123,625.74 ± 8.00 ng/ml and 384.22 ± 5.00 ng/ml of folate, respectively. Five strains were further examined for their ability to synthesize folate in cheese. The folate content increased with ripening up to by 54% after 30 d when L. casei VC199 was used and up to 108% and 113% after 60 d, with L. paracasei SE160 and E. lactis BT161 respectively exceeding 100 ng/100g. Results encourage the use of specific LAB to obtain natural folate bio-enriched dairy products improving folate intake.
乳酸菌（LAB）可通过原位强化来增加食品中的叶酸。从 70 株 LAB 中筛选出在德曼、罗戈萨和 Sharpe/M17 肉汤中生长时能够产生叶酸的能力。干酪乳杆菌、植物乳杆菌、副干酪乳杆菌亚种、鼠李糖乳杆菌、保加利亚乳杆菌、嗜热链球菌、乳球菌乳亚种、粪肠球菌和乳酸肠球菌能够在培养基中合成叶酸，尽管程度不同。进一步通过微生物分析对 47 株产叶酸的菌株进行分析，用于总、额外和细胞内叶酸。粪肠球菌 VC223 和乳酸肠球菌 BT161 能够在培养基中分别产生 123,625.74±8.00ng/ml 和 384.22±5.00ng/ml 的叶酸。进一步对五株菌株进行了在奶酪中合成叶酸的能力的检查。随着成熟度的增加，叶酸含量在 30 天时增加了 54%，当使用干酪乳杆菌 VC199 时，在 60 天时增加了 108%和 113%，而副干酪乳杆菌 SE160 和乳酸肠球菌 BT161 分别超过了 100ng/100g。这些结果鼓励使用特定的 LAB 来获得天然叶酸生物强化乳制品，从而提高叶酸的摄入量。
