Unveiling Neuroprotective Potential in Tempeh Peptide Extracts by In Vitro Screening of Anti-Alzheimer’s Compounds

Background Alzheimer's Disease (AD) incidence and prevalence increase every year, commonly related to neuron inflammation and degeneration conditions. Tempeh, a traditional fermented product from Indonesia, was reported to have anti-inflammatory, antioxidant, and anti-Alzheimer properties. However, anti-Alzheimer properties of tempeh peptide extracts have not been extensively examined. This research studied the effect of the extracted peptide from tempeh in preventing and delaying Alzheimer's disease. Methods Tempeh peptide was extracted using water maceration and quantified using HPLC and spectrophotometry. Anti-Alzheimer properties of tempeh were analyzed with Ellman's assay of anticholinesterase and in vitro gene expression analysis using LPS-induced neural Schwann cells. Results As a result, tempeh contained 19.27% of GABA, which is reported to have anti-Alzheimer properties, and other amino acids. Tempeh peptide extract at 12.5 µg/mL had strong inhibition activity toward acetylcholinesterase at 12.61%, and 100 µg/mL of tempeh peptide extract had 8.97% butyrylcholinesterase inhibition activity. Tempeh peptides extract also altered the expression of various genes related to Alzheimer's disease, such as TNF-α, BACE 1, Ntrk 1, BDNF 2, and APP. Conclusions This research proved that various peptides from tempeh have anti-Alzheimer properties.