Mass Spectroscopic Analysis, MNDO Quantum Chemical Studies and Antifungal Activity of Essential and Recovered Oil Constituents of Lemon-Scented Gum against Three Common Molds

Abstract

The present study described the possibility of using wood-treated oil-fungicide of lemon-scented gum (Corymbia citriodora) from newly emerged leaves and unripened fruits against the infestation of Fusarium culmorum, Rhizoctonia solani and Penicillium chrysogenum. Air-dried wood samples of Melia azedarach were treated with the extracted oils from leaves and unripened fruits from C. citriodora. The main chemical constituents identified in the essential oil (EO) from leaves were citronellal (55.31%), citronellol (21.03%) and isopulegol (10.79%), while in unripened fruits were α-pinene (17.86%), eudesmol (13.9%), limonene (9.19%), γ-terpinen (8.21%), and guaiol (7.88%). For recovered oils (ROs), the major components from leaves were D-limonene (70.23%), γ-terpinene (13.58%), β-pinene (2.40%) and isopregol (2.23%), while, 4-terpineol (21.35%), cis-β-terpineol, (19.33%), D-limonene (14.75%), and γ-terpinene (7.42%) represented the main components in fruits. EOs from leaves and fruits at the amounts of 100, 50 and 25 µL showed the highest inhibition percentage (IP) of 100% against F. culmorum and P. chrysogenum compared to control treatment, while at the amounts of 100, and 50 µL showed 100% IP of R. solani. Wood treated with ROs from leaves and fruits showed IPs of 96.66% and 93.33%, respectively, against the growth of R. solani. The mass spectra of the main components of C. citriodora leaves and fruits’ EOs have been recorded in electron ionization mode at 70 eV and fragmentation has been reported and discussed. On the other hand, different quantum parameters such as the heat of formation, ionization energy total energy, binding energy, electronic energy and dipole moment using the modified neglect of diatomic overlap (MNDO) semi-empirical method have been calculated.

Antifungal Activity of Chitosan Oligomers–Amino Acid Conjugate Complexes against Fusarium culmorum in Spelt (Triticum spelta L.)

“…Hill and L.A.S. Johnson) [16], essential oils of Moroccan wormseed (Dysphania ambrosioides (L.) Mosyakin and Clemants) [17], walnut (Juglans regia L.) green husk extracts [18], extracts from buckwheat grain and hulls [19], phenolic-rich bee products (propolis, bread and pollen) [19], or polyphenol inclusion compounds and conjugate complexes [20,21], among others, have been recently reported.…”

Eucalyptus camaldulensis, Citrus aurantium, and Citrus sinensis Essential Oils as Antifungal Activity against Aspergillus flavus, Aspergillus niger, Aspergillus terreus, and Fusarium culmorum

“…The EOs from Eucalyptus species have been studied in dozen research for their promising in industrial and pharmaceutical applications, which recommended as antimicrobial agents as well as potential insecticidal [21,22]. 1,8-Cineol is the main compound in the leaf EO of Eucalyptus, which can constitute 77% of the leaf EO, and some other constituents of cuminal, aromadendren, D-limonene, 4-terpineol, aromadendral, phellandrene, geraniol, cymene, and phellandral can be identified [1,11,16,22,23]. α-Pinene, p-cymene, α-phellandrene, 1,8-cineole, γ-terpinene, and limonene were found in E. camaldulensis EO collected from eastern Taiwan [24], while p-cymene, β-phellandrene, 1,8-cineole, spathulenol, and cryptone were the main compounds from the aerial parts of E. camaldulensis grown in Italy [25].…”

“…To control fungal growth, biosynthesis of mycotoxin, and food contamination, three main approaches (physical, biological, and chemical treatments) were recognized and used against mycotoxigenic fungi [7,23,[38][39][40][41][42][43][44][45]. The crude EO was more effective than the major compounds, for example, the EO extracted from some Eucalyptus species such as C. camaldulensis was more active against Pseudomonas aeruginosa than the major constituents such as α-pinene, 1,8-cineole, and p-cymene [46].…”

Foliar Application of Bio-Stimulants Enhancing the Production and the Toxicity of Origanum majorana Essential Oils Against Four Rice Seed-Borne Fungi

“…GC/MS with Xcalibur 3.0 data system has threshold values to confirm that all the MS of the compounds were attached to the library. Therefore, measuring their standard index (SI) and reverse standard index (RSI), values ≥ 650 are acceptable to confirm the compounds [35,[75][76][77][78].…”