This study investigated the impact of harvest season and extraction method on the yield, composition, and bioactivity of essential oils (EOs) from wild Rosmarinus officinalis L. plants collected in Algeria. Oils were obtained by hydro distillation (HD), steam distillation (SD), and microwave-assisted distillation (MD) across four seasons and characterized by GC–MS. Camphor, α-pinene, camphene, and 1,8-cineole were consistently dominant, with spring oils, particularly those extracted by microwave-assisted distillation, showing the highest enrichment in oxygenated monoterpenes (up to 59.6%). Functional assays revealed clear seasonal variation, whereas spring oils exhibited the strongest antioxidant capacity, with a FRAP value of 4.63 µg/mL, approaching that of the synthetic standard BHA (6.89 µg/mL), alongside notable anti-inflammatory effects. Antimicrobial screening indicated selective inhibition of Escherichia coli and Candida albicans, while Pseudomonas aeruginosa and Bacillus subtilis remained resistant. Acute toxicity evaluation confirmed safety at 2000 mg/kg. These findings demonstrate that ecological timing and extraction strategy critically determine rosemary EO properties and establish quantitative benchmarks for their pharmaceutical and industrial valorization.

This investigation explored how seasonal variation affects the phytochemical composition and biological potential of Rosmarinus officinalis L., a widely used aromatic and medicinal plant. Aerial parts collected during spring, summer, autumn, and winter were extracted with ethanol and analyzed using LC-ESI-MS/MS, while total phenolic (TPC) and flavonoid (TFC) contents were determined spectrophotometrically. The extracts were evaluated for antioxidant, anti-inflammatory, enzyme inhibitory, analgesic, antimicrobial, cytotoxic, and photoprotective properties. Major constituents identified in all seasons included luteolin, kaempferol, rutin, and biochanin A. The autumn extract contained the highest phenolic (353.21 ± 4.05 µg GAE/mg) and flavonoid (190.11 ± 5.65 µg QE/mg) levels. Antioxidant assays revealed that the autumn extract had the strongest DPPH radical scavenging activity (IC₅₀ = 24.72 ± 0.16 µg/mL), while the spring extract exhibited the greatest reducing power (A_0.5 = 7.62 ± 0.30 µg/mL). The winter extract demonstrated superior anti-inflammatory activity (IC₅₀ = 28.60 ± 2.84 µg/mL), exceeding the reference drug diclofenac. Only the spring extract inhibited urease (IC₅₀ = 62.26 ± 0.58 µg/mL) and moderately inhibited α-amylase. All seasonal extracts showed notable photoprotective potential, with SPF values between 25.18 and 32.46, well above the recommended minimum. The spring extract also presented strong analgesic activity and no acute toxicity up to 2000 mg/kg. Antimicrobial effects were weak, limited to slight inhibition of Staphylococcus aureus, while moderate cytotoxicity was observed against MCF-7 and MDA-MB-231 breast cancer cells. Overall, seasonal variation significantly influenced the chemical profile and bioactivities of R. officinalis, with autumn and spring identified as the most suitable harvesting periods for pharmaceutical and cosmetic applications.

This study aims to investigate the plausible inhibitory capacity of Matricaria pubescens methanolic extract (EMMP) on key diabetes-related enzymes in diabetic rats. A significant increase in the serum and pancreatic α-amylase activity in untreated diabetic rats (Diab) by 61% and 75% respectively produced a remarkable rise in blood glucose levels of 184% compared with the controls. However, the treatment of diabetic rats with the extract (Diab + EMMP) caused a significant decrease in pancreatic α-amylase activity in the pancreas (15%) and in serum (28%) compared to untreated diabetic rats. Therefore, a considerable reduction in blood sugar level has been observed reaching 28%. A significant decrease was observed in the glycated hemoglobin (HbA1c) level (28%) in rats treated with EMMP compared to untreated diabetics. Furthermore a significant increase in the pancreatic serum lipase activity (59%) compared to the control group, led to a distinguished inhibition (21%) in diabetic rats treated with EMMP. A potent protective action of β-cells was observed in diabetic rats treated with EMMP. However, we observed recovery in body weight in the diabetic rats treated with EMMP.