The Molecular Characterization and Biological Assessment of the Leaves Extracts of Loofah Reveal their Nutraceutical Potential.

BACKGROUND: Luffa cylindrica is a plant that is widely distributed in Africa and Asia and can be grown in regions with tropical or subtropical climates. Few patents dealt with Loofah biological properties, including some functional foods formulated from its leaves. OBJECTIVE: This study aimed to structurally and functionally characterize the bioactive compounds of L. cylindrica leaves grown in two different environments. METHODS: The extracts of L. cylindrica leaves collected from two Tunisian locations: Essouasi (LE), a semi-arid region and Medenine (LM), an arid region, were investigated for their phenolic compounds and fatty acids using HPLC/TOF-MS and GC-MS techniques, respectively. Furthermore, the antioxidant capacity was evaluated with DPPH, Chelating effect, Hydroxyl radical and Superoxide anion scavenging activities while the anticancer activity against HeLa cell lines was assessed using xCELLigence real time cell analyzer and lactate dehydrogenase cytotoxicity assay. RESULTS: The antiproliferative capacity of both extracts was time and dose-dependent, with LE presenting the lowest HeLa cell index (CI = 0.035 ± 0.018, 250 µg/ml). LE also showed the best cytotoxic capacity (56.49 ± 0.8%) and antioxidant potential (IC50 = 54.41 ± 1.12 µg/ml for DPPH and 12.12 ± 0.07 µg/ml for chelating effect). 14 phenolic compounds were detected in LE, with ferulic acid being the major compound (5128.5 ± 4.09 µg Phenols/g), while LM had only 6 phenolics. GCMS analysis showed the presence of omega-3 fatty acids in LE. CONCLUSIONS: Our findings suggest that L. cylindrica leaves, especially when collected from semiarid regions, are promising for formulating nutraceuticals of interest.

Phytochemical profile and insecticidal activity of Agave americana leaf extract towards Sitophilus oryzae (L.) (Coleoptera: Curculionidae).

The main objective of the present study is to introduce a new and ecologically safe method for managing the rice weevil, Sitophilus oryzae. Therefore, the Agave americana leaf extract's phytochemical profile, and its insecticidal activity against the adults of S. oryzae were evaluated. The A. americana leaf extract was screened for the following phytochemicals: total phenolics (14.70 ± 0.31 mg GAE/g FW), total flavonoids (5.15 ± 0.18 mg RE/g FW) and saponins (10.32 ± 0.20 mg OAE/g FW). The HPLC-ESI/TOF-MS analysis results revealed that flavonoid glycosides (kaempferol, quercetin, and isorhamnetin derivates) were the major phenolic compounds of the A. americana leaf extract. In addition, the GC-MS analysis identified n-alkanes (77.77%) as significant compounds of the lipophilic fraction from the leaf extract. Moreover, the insecticidal potential was assessed through contact and repellent bioassays towards the rice weevil adults. The LD50, LC50, and RC50 values were 10.55 µg/insect, 8.99 µg/cm2, and 0.055 µg/cm2 for topical application method, treated filter-paper method, and repellent bioassay, respectively. Furthermore, the A. americana leaf extract inhibited digestive enzyme activities, and median inhibition concentrations IC50 were evaluated to be 146.06 ± 1.74 and 86.18 ± 1.08 µg/mL for α-amylase and protease, respectively. Overall, our results highlighted the promising potential of the leaf extract against S. oryzae adults, allowing us to recommend the extract under investigation as an ecofriendly alternative to synthetic insecticides.

Bioactive compounds contents, antioxidant and antimicrobial activities during ripening of Prunus persica L. varieties from the North West of Tunisia.

Bioactive molecules from fruits of four varieties of Prunus persica at different stages of ripening (green, small orange, red) were studied. For example, contents on polyphenols (20.36mg GAE/g FW) and flavonoids (0.764mg RE/g FW) were high and varied according variety. The antioxidant activity, using four different tests (DPPH radical scavenging activity, reducing power, ß carotene bleaching system and TBARS assay) showed that the variety Chatos exhibited the highest antioxidant activity comparing with others varieties. The antibacterial activity of Prunus persica varieties studied seems to be more sensitive against Staphylococcus aureus and Listeria monocytogenes. The capacity of peach DMSO extracts to inhibit Candida albicans growth was more pronounced, especially, in the presence of Chatos DMSO extract. Enzymes inhibition gives results which correlate with polyphenols, flavonoids and condensed tannins contents, and so, confirm the fascinating bioactivity of this fruit.