The double effect of walnut septum extract (Juglans regia L.) counteracts A172 glioblastoma cell survival and bacterial growth

Walnut (Juglans regiaL.) is considered to be a 'superfood' for its multiple protective actions on human health. Walnut extracts have proven antitumor activity in different cancer cell lines. However, the efficacy of septum extract against glioblastoma has still not been investigated. Glioblastoma is the most difficult type of brain cancer to treat. The standard therapy, based on temozolomide, causes several side effects, including neutropenia and lymphocytopenia, which often favor the onset of opportunistic infections. In the present study, the chemical profile of the Sicilian walnut septum ethanolic extract was analyzed using high-performance liquid chromatography (HPLC)-diode array detection and HPLC-electrospray ionization tandem mass spectrometry. The potential cytostatic activity of the extract against the human A172 glioblastoma cell line was investigated and the results showed that the extract could decrease cancer cell proliferation and migration. Using cytofluorimetric analyses and caspase-3 assays, the pro-apoptotic action of walnut extract was demonstrated. Furthermore, the evaluation of the antibacterial activity high-lighted the efficacy of the extract in reducing Gram-positive and Gram-negative bacterial growth, most of which were resistant to the antibiotic, ciprofloxacin. Finally, Prediction of Activity Spectra for Substances analysis showed the predicted antitumor and antibacterial activity of HPLC detected compounds. The promising results could provide novel perspective in the field of chemotherapeutic co-adjuvants.