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Background/Objectives Galeopsis spp. (Lamiaceae) are widely distributed across extensive areas in Romania, being used mainly for their sedative, neuroprotective, antioxidant, anti-inflammatory, expectorant, astringent, and diuretic properties. The paper reports for the first time the investigation of the total phenolic content (TPC), total flavonoid content (TFC), and phenolic acid profile in the roots, aerial parts, and leaves from three wild-grown Galeopsis spp. (G. bifida Boenn., G. speciosa Mill., and G. tetrahit L.), along with their antioxidant and acetylcholinesterase (AChE) inhibitory potentials. Methods: The ultra-high-performance liquid chromatography/ultraviolet/mass spectrometry (HPLC/UV/MS) method was used for the identification and quantification of key phenolic acids. The spectrophotometric method was applied for the determination of TPC, TFC, 2,2-diphenyl-1-picrylhydrazyl (DPPH), and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities and also the ferric-reducing antioxidant power (FRAP). High-performance thin-layer chromatography (HPTLC) was employed for the assessment of in situ antioxidant (DPPH assay) and AChE inhibitory potentials. Results: Galeopsis spp. exhibit significant polyphenol accumulation. Chlorogenic acid was the most abundant compound, with the highest levels detected in G. tetrahit leaves (22,347.907 ± 1117.395 μg/g), followed by G. tetrahit aerial parts (11,678.509 ± 583.925 μg/g) and G. speciosa leaves (8712.628 ± 435.631 μg/g). G. tetrahit leaves had the highest DDPH radical scavenging activity, with a half-maximal inhibitory concentration (IC₅₀) of 0.458 ± 0.03 mg/mL, demonstrating a markedly stronger antioxidant effect. Leaves consistently showed the strongest DPPH activity across all species, with G. speciosa leaves also displaying a low IC₅₀ value of 0.789 ± 0.03 mg/mL, comparable to G. tetrahit. Aerial parts exhibited an intermediate effect, with G. bifida aerial parts showing an IC₅₀ of 8.102 ± 0.49 mg/mL, while G. tetrahit aerial parts demonstrated stronger activity at 1.511 ± 0.11 mg/mL. AChE inhibition activity increased progressively from the roots to aerial parts to leaves, with leaves consistently exhibiting the strongest inhibitory effects across all Galeopsis spp. G. tetrahit leaves had the strongest inhibition, with an IC₅₀ of 4.002 ± 0.32 mg/mL, followed by G. speciosa leaves (6.92 ± 0.14 mg/mL) and G. bifida leaves (6.97 ± 0.68 mg/mL). Conclusions: Our study provides a comprehensive analysis of the phenolic acid content, in vitro antioxidant activity, and neuroprotective potential of three Galeopsis spp. (G. bifida, G. speciosa, and G. tetrahit) from the southwestern Romanian flora. Full article

Effective and sustainable weed management in agricultural fields is a prerequisite for increasing crop yield without negatively impacting the environment. The aim of this study was to explore how varying nitrogen (N) availability in cropping arrangements of pea (Pisum sativum) and barley (Hordeum vulgare) grown as sole crops and intercrops at different fertilization levels and considering different N sources (soil mineralization, N fixation, N fertilizer) affects the response of weed species with differential N responsiveness. Crop and weed biomass were sampled at flowering and maturity. The total N content and ¹⁵N isotope signatures were analyzed to differentiate between N sources and to estimate the amount of N available to weeds. The highly N-responsive weed (Chenopodium album) accumulated more N and biomass than the weed with reduced N responsiveness (Galeopsis spp.). Fertilizer supply favored Chenopodium album, but not the crops. Altered soil N availability caused a shift in the dominance of the nitrophilic weed species towards the highly N-responsive species. This shift in dominance could affect the long-term weed community composition and thus have implications for sustainable weed management. Full article