Stress-Associated Phenylpropanoid Metabolism and Nutritional Composition in Wild vs. MeJA-Elicited In Vitro Hypericum perforatum and Portulaca oleracea

Background/Objectives: The phenylpropanoid pathway in plants plays a pivotal role in the biosynthesis of secondary metabolites in plants, responding to environmental stresses to enhance protective compounds such as phenolic acids and flavonoids. This study compares the phenolic profiles, vitamins, sugars, and mineral elements of Hypericum perforatum and Portulaca oleracea grown under two contrasting conditions: wild habitats and in vitro cultures on Murashige–Skoog medium supplemented with methyl jasmonate (MeJA, 25–50 µM). Methods: Aerial parts were extracted with 70% ethanol and analyzed for phenolic profiles (rutin, caffeic acid, chlorogenic acid, quercetin), proximate composition, free sugars, vitamins, and mineral elements (n = 3, ANOVA/Tukey, p < 0.05). In vitro cultures were maintained under MeJA-elicited conditions; however, the present design does not allow for the separation of MeJA-specific effects from general in vitro growth conditions. Results: Wild samples showed higher phenolic contents (e.g., rutin in Hypericum perforatum: 22.224 ± 0.65 mg/g vs. 15.190 ± 0.311 mg/g in vitro; quercetin in Portulaca oleracea: 0.874 ± 0.157 mg/g vs. 0.444 ± 0.157 mg/g), highlighting the stress-induced activation of secondary metabolism in natural environments. Conclusions: Overall, the data indicate that wild-growing plants accumulate higher levels of key phenylpropanoids than MeJA-elicited in vitro cultures, underscoring the complexity of reproducing natural stress-associated metabolic patterns under controlled conditions.