Cashew apple (Anacardium occidentale L.) extract from a by-product of juice processing: assessment of its toxicity, antiproliferative and antimicrobial activities.

Cashew apple extract (CAE) is a product with intense yellow color obtained from residual fibers of juice processing. Although CAE is known to be rich in carotenoids and anacardic acids, the biological activities of this potential natural food colorant remain unexplored. The present study is the first to investigate the toxicity, antiproliferative and antimicrobial activities of the lyophilized CAE (L-CAE) and its encapsulated products, using maltodextrin (M-CAE) or cashew gum (CG-CAE) as carriers. In addition to their high carotenoid content, the phenolic contents in all materials was determined using UPLC-QTOF-MSE. The acute toxicity was performed using adult zebrafish (Danio rerio); antiproliferative activity was assessed using seven different human tumor cell lines [U-251 (glioblastoma), MCF-7 (breast, adenocarcinoma), NCI-ADR/RES (multidrug-resistant ovarian adenocarcinoma), NCI-H-460 (lung, large cell carcinoma), PC-3 (prostate, adenocarcinoma), OVCAR-3 (ovarian adenocarcinoma), and HT-29 (colon, adenocarcinoma)] and an immortalized human keratinocyte (HaCaT) while the antimicrobioal activity was evaluated on Staphylococcus aureus ATCC 25923, Listeria monocytogenes ATCC 19115, Escherichia coli ATCC 25922 and Salmonella Typhimurium ATCC 51812 microorganisms. Both lyophilized and encapsulated CAE samples did not exert acute toxicity against zebrafish neither antiproliferative effect against human tumor and non-tumor cell lines. Further, L-CAE showed potential antimicrobial activity against Listeria monocytogenes, which was confirmed using electron microscopy. The current findings demonstrated that CAE is a potential source of bioactive compounds to use as an additive in the food industry.

Effect of pulsed light on postharvest disease control-related metabolomic variation in melon (Cucumis melo) artificially inoculated with Fusarium pallidoroseum.

Pulsed light, as a postharvest technology, is an alternative to traditional fungicides, and can be used on a wide variety of fruit and vegetables for sanitization or pathogen control. In addition to these applications, other effects also are detected in vegetal cells, including changes in metabolism and secondary metabolite production, which directly affect disease control response mechanisms. This study aimed to evaluate pulsed ultraviolet light in controlling postharvest rot, caused by Fusarium pallidoroseum in 'Spanish' melon, in natura, and its implications in disease control as a function of metabolomic variation to fungicidal or fungistatic effects. The dose of pulsed light (PL) that inhibited F. pallidoroseum growth in melons (Cucumis melo var. Spanish) was 9 KJ m-2. Ultra-performance liquid chromatography (UPLC) coupled to a quadrupole-time-of-flight (QTOF) mass analyzer identified 12 compounds based on tandem mass spectrometry (MS/MS) fragmentation patterns. Chemometric analysis by Principal Components Analysis (PCA) and Orthogonal Partial Least Squared Discriminant Analysis (OPLS-DA) and corresponding S-Plot were used to evaluate the changes in fruit metabolism. PL technology provided protection against postharvest disease in melons, directly inhibiting the growth of F. pallidoroseum through the upregulation of specific fruit biomarkers such as pipecolic acid (11), saponarin (7), and orientin (3), which acted as major markers for the defense system against pathogens. PL can thus be proposed as a postharvest technology to prevent chemical fungicides and may be applied to reduce the decay of melon quality during its export and storage.