Center for Food Analysis (NAL), Technological Development Support Laboratory (LADETEC), Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro, RJ 21941-598, Brazil.
Laboratory of Advanced Analysis in Biochemistry and Molecular Biology (LAABBM), Department of Biochemistry, Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro, RJ 21941-909, Brazil.
Oxid Med Cell Longev. 2021 Oct 27;2021:9081738. doi: 10.1155/2021/9081738. eCollection 2021.
Despite evidence of health benefits from kefir administration, a systematic review with meta-analysis on bioactive compounds associated with these benefits is still absent in the literature. Kefir is fermented milk resulting from the metabolism of a complex microbiota in symbiosis. Recent researches have investigated the bioactive compounds responsible for the preventive and therapeutic effects attributed to kefir. However, differences in functional potential between industrial and artisanal kefir are still controversial. Firstly, we identified differences in the microbial composition among both types of kefir. Available evidence concerning the action of different bioactive compounds from kefir on health, both from and studies, was subsequently summarized to draw a primary conclusion of the dose and the intervention time for effect, the producer microorganisms, the precursor in the milk, and the action mechanism. Meta-analysis was performed to investigate the statistically significant differences ( < 0.05) between intervention and control and between both types of kefir for each health effect studied. In summary, the bioactive compounds more commonly reported were exopolysaccharides, including kefiran, bioactive peptides, and organic acids, especially lactic acid. Kefir bioactive compounds presented antimicrobial, anticancer, and immune-modulatory activities corroborated by the meta-analysis. However, clinical evidence is urgently needed to strengthen the practical applicability of these bioactive compounds. The mechanisms of their action were diverse, indicating that they can act by different signaling pathways. Still, industrial and artisanal kefir may differ regarding functional potential-OR of 8.56 (95% CI: 2.27-32.21, ≤ .001)-according to the observed health effect, which can be associated with differences in the microbial composition between both types of kefir.
尽管有证据表明食用克菲尔能带来健康益处，但关于与这些益处相关的生物活性化合物的系统评价和荟萃分析在文献中仍然缺失。克菲尔是一种发酵乳，由共生的复杂微生物群落代谢而成。最近的研究已经调查了负责预防和治疗克菲尔归因于的生物活性化合物。然而，工业和手工克菲尔之间在功能潜力方面的差异仍然存在争议。首先，我们在这两种克菲尔之间发现了微生物组成的差异。随后，总结了关于克菲尔中不同生物活性化合物对健康的作用的现有证据，包括 和 研究，以得出初步结论，包括剂量和干预时间、生产微生物、牛奶中的前体以及作用机制。进行荟萃分析以调查每个研究健康效果的干预和对照组之间以及两种克菲尔之间的统计学显著差异（<0.05）。总之，更常报道的生物活性化合物是胞外多糖，包括克菲尔聚糖、生物活性肽和有机酸，特别是乳酸。克菲尔生物活性化合物具有抗菌、抗癌和免疫调节活性，荟萃分析结果证实了这一点。然而，迫切需要临床证据来加强这些生物活性化合物的实际应用。它们的作用机制多种多样，表明它们可以通过不同的信号通路发挥作用。然而，根据观察到的健康效果，工业和手工克菲尔在功能潜力方面可能存在差异——观察到的优势比为 8.56（95%置信区间：2.27-32.21，<0.001）——这可能与两种克菲尔之间的微生物组成差异有关。
