PH-sensitive intelligent films offer a novel strategy for real-time monitoring of food freshness via visible color changes. This study valorizes onion peel powder (OPP), a polyphenol-rich agro-industrial by-product, by incorporating it into cassava starch-based films at three concentrations (1O, 2O, 3O). Increasing OPP content led to significantly higher total phenolic and flavonoid levels, enhancing the films’ antioxidant properties (p < 0.0001). While the films exhibited selective antibacterial effects, pronounced inhibition zones were observed against Pseudomonas aeruginosa and Escherichia coli, two relevant meat spoilage and pathogenic bacteria. The films displayed clear and gradual color shifts from light to dark brown across a wide pH range (1–13), confirming their suitability as pH indicators. When applied as labels in minced beef packaging stored at 4 °C, the films successfully tracked freshness over 13 days. Film color changes were strongly correlated with microbial load and pH variations, accurately flagging spoilage onset. These findings support the potential of cassava starch/OPP films as biodegradable, cost-effective intelligent packaging tools, contributing to food safety, waste reduction, and circular bioeconomy principles. The system provides a practical, non-invasive solution for meat freshness monitoring without requiring instrumentation.

Many commercial pharmaceutical drugs and herbal remedies derived from medicinal plants rely on these metabolites. In this study, we investigated the influence of climatic factors and soil composition on the quantity, quality and efficiency of phenolic compounds in the typical species Aristolochia longa L. from three stations in eastern Algeria, each of which is located in a different bioclimatic stage.To characterize the chemical profile of crude methanolic extracts of three parts of Aristolochia longa L. from three different regions using liquid chromatography-mass spectrometry (LC-MS) analysis, also, their biological and pharmacological properties were evaluated: the antioxidant capacities (DPPH., ABTS⁻⁺, CUPRAC, FRAP, β-carotene-linoleic acid bleaching assays, ability to inhibit enzymes against acetylcholinesterase (AChE) and buthyrylcholinesterase (BChE)]. Secondary metabolites were extracted from leaves, stems and roots of Aristolochia longa L. The amount of polyphenols, flavonoids, flavones and flavonols were determined by colorimetric method. Various in vitro biochemical tests were performed to evaluate the antioxidant and free radical scavenging properties, the neuroprotective abilities of different extract were examined against the acetylcholinesterase and buthyrylcholinesterase enzymes. The components of the active extracts were identified by LC-MS and compared to reference substances. The antibacterial activity was evaluated using the agar disk diffusion method on reference strains of ATCC types. The results showed that Aristolochia longa L. extracts had strong antioxidant activity in all assays and a strong inhibitory effect against AChE and BChE enzymes, as well as antibacterial capacities against different strains. LC-MS analysis revealed the presence of eight phenolic compounds in methanolic extract of Aristolochia longa L. from leaves: apigenin, diosmin, quercetin, quercetine-3-glycoside, apigenin 7-O glycoside, rutin, neohesperidin and taxifolin. This work revealed significant differences in the yield sand chemical composition of leaves of Aristolochia longa L., collected from three locations in Algeria. Although the main components of the all extracts of leaves are common, however, their percentages are different. Furthermore, our study demonstrates a high variation in biological activity potentials according to parts of species and populations. This point out the importance of the geographic origin of the populations and the growing conditions which could significantly affect the composition and their biological activities.