ABSTRACT
This research was designed to investigate the metabolite profiling, phenolics, and flavonoids content as well as the potential nematicidal properties of decoction (ZpDe), orange-yellow resin (ZpRe) and essential oil (ZpEO) from Argentinean medicinal plant Zuccagnia punctata Cav. Additionally, the antioxidant and antibacterial properties of ZpDe and ZpEO were determined. Metabolite profiling was obtained by an ultrahigh-resolution liquid chromatography MS analysis (UHPLC-ESI-QTOF/OT-MS-MS) and GCMS. The nematicidal activity was assayed by a standardized method against Meloidogyne incognita. The antioxidant properties were screened by four methods: (2,2-diphenyl-1-picrylhydrazyl assay (DPPH), Trolox equivalent antioxidant activity assay (TEAC), ferric-reducing antioxidant power assay (FRAP), and lipid peroxidation in erythrocytes (ILP). The antibacterial activity was evaluated according to the Clinical and Laboratory Standards Institute (CLSI) rules. The ZpDe, ZpRe and ZpEO displayed a strong nematicidal activity with an LC50 of 0.208, 0.017 and 0.142 mg/mL, respectively. On the other hand, the ZpDe showed a strong DPPH scavenging activity (IC50 = 28.54 µg/mL); ILP of 87.75% at 250 µg ZpDe/mL and moderated antimicrobial activity. The ZpEO showed promising activity against a panel of yeasts Candida albicans and non-albicans (ATCC and clinically isolated) with MIC values from 750 to 1500 µg/mL. The ZpDe showed a content of phenolics and flavonoid compounds of 241 mg GAE/g and 10 mg EQ/g, respectively. Fifty phenolic compounds were identified in ZpDe by ultrahigh-resolution liquid chromatography (UHPLC-PDA- Q-TOF-MS) analysis, while forty-six phenolic compounds were identified in ZpRe by UHPLC-ESI-Q-OT-MS-MS and twenty-nine in ZpEO using a GC-MS analysis, updating the knowledge on the chemical profile of this species. The results support and standardize this medicinal plant mainly as a potential environmentally friendly and sustainable bionematicide for the control of Argentinean horticultural crops including tomatoes and peppers and as a source of antimicrobial and antioxidant compounds which could be further explored and exploited for potential applications.
ABSTRACT
Sitophilus zeamais is a primary pest of maize. Our aim was to perform a qualitative review and meta-analyses with 56 scientific articles published from 1 January 2000 to 1 October 2022 dealing with direct (topical application) and indirect (impregnation of essential oils, EOs, onto filter paper or maize grains) contact toxicity of EOs against S. zeamais. Three independent meta-analyses of single means of LD50 (direct contact) and LC50 (indirect contact) were conducted using a random effect model. Essential oils more frequently evaluated were those belonging to Asteraceae, Apiaceae, Lamiaceae, Myrtaceae, Piperaceae, and Rutaceae. The LC50 global mean values were 33.19 µg/insect (CI95 29.81-36.95) for topical application; 0.40 µL/cm2 (CI95 0.25-0.65) for filter paper indirect contact; and 0.50 µL/g maize (CI95 0.27-0.90) for maize grains indirect contact. The species Carum carvi, Salvia umbratica, Ilicium difengpi, Periploca sepium, Cephalotaxus sinensis, Murraya exotica, Rhododendron anthopogonoides, Ruta graveolens, Eucalyptus viminalis, Ocotea odorifera, Eucalyptus globulus, Eucalyptus dunnii, Anethum graveolens, Ilicium verum, Cryptocarya alba, Azadirachta indica, Chenopodium ambrosioides, Cupressus semperivens, Schinus molle, Piper hispidinervum, Mentha longifolia, and Croton pulegiodorus showed LC50 or LD50 values lower than the global means, indicating good insecticidal properties. Our results showed that EOs have great potential to be used as bioinsecticides against S. zeamais.
