Tempe, Tofu, and Amyloid-β 1-40 Serum Levels in Ovariectomized Rats

Effects of Tempeh Probiotics on Elderly With Cognitive Impairment

Introduction

Oral consumption of probiotics can alter Gut Microbiota by causing changes in the production of probiotic derivatives. Therefore, by utilizing Gut-Brain-Axis (GBA), probiotics could provide an opportunity for central nervous system (CNS) modulation, including cognitive function. Tempeh is a traditional Indonesian food rich in probiotics and beneficial for cognitive function. However, the type of probiotics that play a role in cognitive improvement and the number of probiotics needed for the benefits of increasing cognitive function was unknown.

Method

This experimental study involved a total of 93 subjects, divided into 3 groups: A, B and C/control (n: 33, 32, and 28), who were provided with probiotic supplementation isolated from tempeh for 12 weeks intervention. Inclusion criteria were age > 60 years, and memory impairment with the third repetition value of Word List Memory Immediate Recall (WLMIR) < 7. Subjects with diabetes were excluded. Cognitive function examinations were carried out before and after treatment. The tempeh-derived probiotics were prepared trough several processes. Genomic isolation, detection of GABA-encoding genes, and species identification using the 16S-rRNA gene encoding were performed.

Results

The probiotics isolate used in the intervention was identified as Limosilactobacillus fermentum. We assigned this isolate as L. fermentum A2.8. The presence of the gene encoding GABA was found on this isolate. There was an increase in the cognitive domains of memory, learning process, and verbal fluency (p < 0.05) in group A (probiotics at concentration of 10⁸ CFU/mL). Memory function, visuospatial, and verbal fluency improved (p < 0.05) in group B (probiotics at concentration of 10⁷ CFU/mL). Only an increase in the memory domain was observed in the control group. Improvement of the learning process occurred only in group A (p = 0.006).

Conclusion

Administration of probiotics derived from L. fermentum A2.8 increased the cognitive domains of memory, language and visuospatial function. However, probiotic supplementation at a concentration of 10⁸ CFU/mL was better in improving the learning process. This study succeeded in detecting Lactic Acid Bacterial isolates L. fermentum A2.8 that enclosed gene encoding glutamate decarboxylase (gad) which is involved in the synthesis of -aminobutyric acid (GABA), a neurotransmitter vital for cognitive function.

Tempeh Consumption and Cognitive Improvement in Mild Cognitive Impairment

INTRODUCTION

Tempeh consumption has been linked to the improvement of cognitive function in older people. However, to what extent the amount of microorganism or the size of tempeh serving consumed per day influences the benefit to cognitive functions has not yet been studied.

METHODS

This experimental study involved a total of 90 respondents, who were divided into 3 groups: group A (consuming 100 g of Tempeh A/day), group B (consuming 100 g of Tempeh B/day), and group C (control). Intervention was given for 6 months. Cognitive assessments were done before and after the intervention. Blood uric acid level was checked at the end of intervention to examine the effect of tempeh consumption on this. The inclusion criteria were respondents aged 60 years or over with mild cognitive impairment (MCI) who agreed not to consume other fermented food during the study period. Respondents with diabetes were excluded.

RESULTS

There were 84 subjects at the end of the study, majority being female (71.4%) and aged over 65 years (72.6%). An increase in global cognitive scores was found in both groups A and B. The increase in language domain scores was found only in group A.

CONCLUSION

Both Tempeh A or Tempeh B consumption for 6 months appeared to be beneficial in improving global cognitive function of older people with MCI. Consuming Tempeh A, which had a lower number of microorganisms, was also associated with an improvement in the language domain.