Abstract
Nutrient optimization of Lactobacillus plantarum MTCC 1325 with cinnamon (40 µg/mL) and pantothenic acid (4 µg/mL) resulted in a chloroform extract of Media D that exhibited a strong activity profile relevant to the therapeutic approach to Alzheimer's disease. Across 20-100 µg/mL extracts were non-cytotoxic to undifferentiated PC12 cells. Chloroform extract of Media D showed potent radical scavenging [IC₅₀(superoxide) = 41.7 ± 2.1 µg/mL, IC₅₀(NO) = 33.4 ± 1.1 µg/mL], high total phenolics (68.6 ± 1.1 mg GAE/g), and acetylcholinesterase inhibition [IC₅₀ = 33.2 ± 4.2 µg/mL, galantamine (standard) = 22.5 ± 3.2 µg/mL]. Pre-treatment with chloroform extract of Media D reduced LPS-induced cytotoxicity [IC₅₀ = 32.6 ± 3.6 µg/mL] and lowered nitrite accumulation up to 1.69-fold versus LPS. GC-MS of the active fraction resolved six constituents, consistent with lipid and aromatic metabolites. Together, these results support a nutrient-first media design strategy, demonstrating that selective modulation of media composition under fixed incubation parameters can enrich L. plantarum culture-derived metabolites with antioxidants, anti-inflammatory, and AChE inhibitory activities related to the medical management of AD. This is a preliminary in vitro study using one strain and a single-cell model, Extract were crude and tested with modest replication, and library matched GC-MS identification. Mechanistic markers were not quantified, and in vivo validation is warranted.