No abstract

Agricultural by-products represent one of the biggest pollutants for the environment, therefore, investigating new sources for the extraction of bioactive compounds is a topic of great interest for the entire scientific community. This work is aimed at studying the chemical composition (pigments, phenolics, volatile compounds) and biological activities (antioxidant and antimicrobial properties) of young and mature leaves of five eggplant cultivars (Solanum melongena L.) grown in Tunisia (Tizona, A1014, Nawel, A336, and Mirval). Pigment analysis showed no statistical variations between the two types of leaves, whereas higher levels of anthocyanins were recorded in young leaves of three out of five cultivars (24.7-52.8 mg 100 g À 1). Total phenolic compounds (966.5-2072.6 mg 100 g À 1) and o-diphenols (343.9-741.2 mg 100 g À 1) contents varied significantly according to leaf age and cultivar. However, no statistically significant variation between young and mature leaves was found in flavonols and tannins content. As for volatile profiles, 62 constituents were characterized with non-terpene derivatives (52.0-61.6 %) and apocarotenes (19.9-35.6 %) as major chemical classes. Regarding the antioxidant activity, methanol extracts of Tizona cultivar mature leaves displayed important antiradical properties using DPPH, ABTS, and phosphomolybdenum assays (IC 50 0.1, 0.2 and 0.01 mg mL À 1 , respectively). With regards to reducing power determination, the most active extract was obtained from mature A1014 leaves. Further, young Mirval leaves proved to be significantly active from a bactericidal point of view against Candida albicans and Staphylococcus aureus of 3.1 mg mL À 1 and 0.2 mg mL À 1 MBC, respectively. In conclusion, eggplant leaves are a noteworthy source of antioxidant and antimicrobial compounds with potential use in the pharmaceutical, the cosmetics and the food industries.

We have fabricated an implantable dressing material able to reduce antipressure ulcer disease. This biomaterial is based on electrospun poly(lactic acid) (PLA) nanofibers (NFs) containing the hydroethanolic extract (HE) of T. ramosissimum. Optimized synthesis conditions (17-PLA/HE NFs) resulted in homogeneous and nonwoven mat structures formed by polymeric NFs. We have included a kinetic release assay where the chemical structures of the main released compounds were identified using nuclear magnetic resonance. The identified compounds include molecules from the family of flavonoids, monoterpenoids, hydroxycinnamic derivatives, and phenolic acids. Interestingly, the terpenoid teuhircoside has been identified in Teucrium ramosissimum for the first time. We have also performed in vivo woundhealing investigations, examining the process of healing of induced pressure ulcers in mice, once applying different dressing materials generated in this work. In these in vivo assays, we were able to demonstrate that the implantable 17-PLA/HE NF material improves wound-healing capabilities, reduces the injury area, and provides a high wound closure percentage from the first days of application. Finally, histological assays showed complete reepithelialization with 17-PLA/HE NFs. This investigation offers the possibility to fabricate implantable materials containing only the here-determined released compounds.

Globularia alypum L. (GA) is a Mediterranean plant of the Globulariaceae family which is widely used in traditional Tunisian medicine. The main goal of this study was to evaluate the phytochemical composition, antioxidant, antibacterial, and antibiofilm activities, and the antiproliferative potential of different extracts of this plant. The identification and the quantification of the different constituents of extracts were determined using gas chromatography–mass spectrometry (GC-MS). The antioxidant activities were evaluated using spectrophotometric methods and chemical tests. The antiproliferative study was based on the use of colorectal cancer SW620 cells, including an antibacterial assessment with the microdilution method and analysis of the antibiofilm effects via the crystal violet assay. All extracts presented several components, mainly sesquiterpenes, hydrocarbon, and oxygenated monoterpenes. The results revealed that the maceration extract had the most important antioxidant effect (IC50 = 0.04 and 0.15 mg/mL), followed by the sonication extract (IC50 = 0.18 and 0.28 mg/mL). However, the sonication extract demonstrated significant antiproliferative (IC50 = 20 µg/mL), antibacterial (MIC = 6.25 mg/mLand MBC > 25 mg/mL), and antibiofilm (35.78% at 25 mg/mL) properties against S. aureus. The results achieved confirm the important role of this plant as a source of therapeutic activities.