Department of Agricultural and Food Sciences, University of Bologna, p.zza Goidanich 60, 47521 Cesena (FC), Italy; Interdepartmental Center for Industrial Agri-food Research, University of Bologna, via Quinto Bucci 336, 47521 Cesena (FC), Italy.
Department of Pharmacy and Biotechnology, University of Bologna, via San Donato 19/2, 40127 Bologna (BO), Italy.
Food Res Int. 2020 Nov;137:109580. doi: 10.1016/j.foodres.2020.109580. Epub 2020 Jul 23.
Lactobacillus crispatus strain BC4, isolated from the human healthy vaginal environment and characterised by a strong antimicrobial activity against urogenital pathogens and foodborne microorganisms, was employed as a probiotic culture in the cheesemaking of the soft cheese Squacquerone. Such cheese is intended as a "gender food", that could be used as a hedonistic dietary strategy to reduce the incidence of woman vaginal dysbiosis and infections, given the evidence that a probiotic strain able to survive to the entire digestive process once ingested, can pass from intestine to vagina. This work was aimed to evaluate the resistance of L. crispatus BC4, carried in Squacquerone cheese, to different challenges of the human gastrointestinal tract, including the colon stage. The digestion process was tested using a Simulator of the Human Intestinal Microbial Ecosystem (SHIME®). The viability and metabolic activity of L. crispatus BC4 during the colon simulation were monitored by qPCR and gas chromatography, respectively, also in the presence of a complex microbiota. The results showed that L. crispatus BC4 survival was not affected by the gastric condition, while it was significantly affected by bile salts and pancreatic juice in small intestine conditions, where it decreased of approx. 0.6 log (colony-forming units) CFU/g. Differently, during colon simulation L. crispatus BC4 was able to grow in sterile colon conditions and to maintain viability in the presence of a complex microbiota. Moreover, during colon simulation, L. crispatus BC4 was metabolically active as demonstrated by the higher production of short chain fatty acids (SCFA) and lactate. In the presence of a complex gut microbiota, a decrease of lactate was observed, due to its conversion into propionate (anti-cholesterol activity) and butyrate (anti-inflammatory activity) by cross-feeding. However, no differences in propionate and butyrate production could be observed between control cheese and cheese containing L. crispatus BC4. Despite this may appear as a negative outcome, it must be taken into account that, in this setup, only a single dose of the cheese was tested and the outcome of the colonization and impact of the gut microbiota might be different when daily repeated doses are tested.
从健康女性阴道环境中分离出的卷曲乳杆菌（Lactobacillus crispatus）菌株 BC4 具有很强的抗泌尿生殖道病原体和食源微生物的抗菌活性，被用作软奶酪 Squacquerone 制作过程中的益生菌培养物。这种奶酪被认为是一种“性别食品”，可以作为一种享乐饮食策略，以降低女性阴道菌群失调和感染的发生率，因为有证据表明，摄入后能够在整个消化过程中存活下来的益生菌菌株，可以从肠道传递到阴道。本研究旨在评估卷曲乳杆菌（Lactobacillus crispatus）BC4 在 Squacquerone 奶酪中的耐受力，该菌株能够抵抗人体胃肠道的不同挑战，包括结肠阶段。使用人类肠道微生物生态系统模拟器（Simulator of the Human Intestinal Microbial Ecosystem，SHIME®）测试消化过程。通过 qPCR 和气相色谱法分别监测结肠模拟过程中 L. crispatus BC4 的存活和代谢活性，同时也存在复杂的微生物群。结果表明，L. crispatus BC4 的存活不受胃条件的影响，而在小肠条件下的胆汁盐和胰液中受到显著影响，其在无菌结肠条件下能够生长并在复杂微生物群存在下保持存活能力。在小肠条件下，其数量减少了约 0.6 个对数（菌落形成单位）CFU/g。相比之下，在结肠模拟中，L. crispatus BC4 的生存能力在存在复杂微生物群的情况下不受影响。此外，在结肠模拟过程中，L. crispatus BC4 表现出代谢活性，这表现为短链脂肪酸（short chain fatty acids，SCFA）和乳酸的产量更高。在存在复杂肠道微生物群的情况下，由于乳酸被转化为丙酸（抗胆固醇活性）和丁酸（抗炎活性），乳酸的产量减少了。然而，在对照奶酪和含有 L. crispatus BC4 的奶酪之间，丙酸和丁酸的产生没有差异。尽管这可能看起来是一个负面结果，但必须考虑到，在这种情况下，仅测试了奶酪的单一剂量，并且当每天重复剂量时，定植和肠道微生物群的影响可能会有所不同。
