1 Introduction

Plant essential oils (EOs) and extracts play a potential role as alternatives to fungicidal agents that are currently used because of their contact inhibition, penetration, and volatile effect. Several EOs have the potential to control different fungal species and can exert strong antifungal activities [1,2,3,4,5].

Corymbia citriodora (Hook.) K.D.Hill & L.A.S.Johnson or Eucalyptus citriodora Hook., the lemon-scented gum, its EOs, and phenolic and flavonoid compounds have great potential uses as antimicrobial and antioxidant activities [6,7,8,9]. A qualitative phytochemical analysis was performed for the detection of alkaloids, cardiac glycosides, flavonoids, saponins, sterols, tannins, and phenols [10]. Phytochemical studies on E. citriodora kino have described the isolation of triterpenoids, phenolics, and flavonoids [11, 12]. Leaf extract showed promising values against Staphylococcus aureus [13]. Citronellal, citronellyl acetate, and trans-caryophyllene were the major compounds in the leaf EO and showed the highest antibacterial activity towards Staphylococcus aureus and Bacillus subtilis and antifungal activity against Aspergillus fumigatus and Saccharomyces cerevisiae [14]. C. citriodora possesses a slight cytotoxic effect which is observed in their study. Leaf extract of plants can delay the loss of climbing ability in drosophila flies [15].

Cupressus macrocarpa Hartweg. ex Gordon (Callitropsis macrocarpa) (family Cupressaceae), or Monterey Cypress [16, 17], is traditionally used in rheumatism, whooping cough, styptic problem, improve bladder tone, and coadjuvant [18, 19]. Various phytoconstituents revealed the presence of carbohydrates, anthraquinone glycosides, cardiac glycosides, phenolics, EOs, flavonoids, saponin, protein, amino acid, and sterols in different extracts [20]. This plant contains diterpenes, monoterpenes, biflavonoids, and sesquiterpenes [9, 21,22,23]. The biflavonoid isolated from Cup. macrocarpa was shown a hepato- and nephro-protective activity in mice against carbon tetrachlo-ride-induced toxicity [23].

Syzygium cumini (L.) Skeels (jambolan) or Eugenia jambolana, common plum and java plum, is one of the widely used medicinal plants [24]. The leaf EO of S. cumini was found to be good antibacterial activity [25]. The EO showed significant activity against Leishmania amazonensis [26]. Leaf EO from S. cumini with its main α-caryophyllene, β-caryophyllene, and terpineol showed antimycobacterial activity [27].

Extracts and EOs from several medicinal and higher plants have been used to protect wood and other wood-based products and objects from mold infestations [28]. In this context, the inhibitory effects of eighteen EOs isolated from Egyptian plants were evaluated against two wood decay fungi, Ganoderma lucidum and Hexagonia apiaria. The EOs revealed various mycelial growth inhibitions against the tested fungi depending on fungal species and tested EOs [29]. The use of natural substances that do not have undesirable side effects in place of harmful ways and the implementation of safe, unique substances have been the main topics of new and alternative research [30]. Many plants have natural chemical components such as EOs, phenols, flavonoids, alkaloids, coumarins, and tannins that are employed as nutrition, medicines, and bioactive molecules [31]. Plant-derived natural products may be the ideal solution for safely halting the biodegradation of wood [32,33,34,35].

In order to produce a useful practical approach for preventing the growth of fungi on wood, this work seeks to compile the use of pure essential oils and extracts from the trees Corymbia citriodora, Cupressus macrocarpa, and Syzygium cumini. This was accomplished by applying extracts and essential oils to Scots pine sapwood (Pinus sylvestris) and testing them against the growth of the fungus Fusarium solani. For additional analytical techniques, GC–MS and HPLC were employed to identify chemical components.

2 Materials and methods

2.1 Plant material

Intact fresh leaves of three trees namely Corymbia citriodora, Cupressus macrocarpa, and Syzygium cumini were collected from Alexandria, Egypt, where C. macrocarpa and S. cumini were collected from the garden of the Faculty of Agriculture, Alexandria University, and the leaves from C. citriodora were collected from a plantation located at Alexandria-Cairo desert road (Albostan area), Alexandria, Egypt. The collected trees have been identified at the Department of Forestry and Wood Technology, Faculty of Agriculture, Alexandria University, Alexandria, Egypt, with their voucher numbers Z007, Z008, and Z009, for C. citriodora, Cup. macrocarpa, and S. cumini, respectively.

2.2 Extraction of the essential oil

The extraction process of the essential oils (EOs) from the fresh leaves of three trees C. citriodora, Cup. macrocarpa, and S. cumini. Plant material of about 100 g was washed using tap water and then cut into small pieces using scissors and put into a 2-L flask containing 1000 mL of distilled water (DW) and extracted by the hydrodistillation method using a Clevenger-type apparatus for 3 h [36]. After obtaining the EOs, they were over anhydrous sodium sulfate and kept dry in sealed Eppendorf tubes stored at 4 °C until chemical and bioassay analyses. The yields of EOs were 4.5, 2.5, and 0.08 mL/100 g plant fresh leaves from C. citriodora, Cup. macrocarpa, and S. cumini, respectively.

2.3 Gas chromatography–mass spectrometry (GC–MS) analysis of the essential oil

The chemical composition of the EOs was performed using Trace GC-TSQ mass spectrometer (Thermo Scientific, Austin, TX, USA) with a direct capillary column TG–5MS (30 m × 0.25 mm × 0.25 µm film thickness). The column oven temperature was initially held at 50 °C and then increased by 5 °C/min to 250 °C held for 2 min and increased to the final temperature of 300 °C by 30 °C/min and held for 2 min. The injector and MS transfer line temperatures were kept at 270 and 260 °C, respectively. Helium was used as a carrier gas at a constant flow rate of 1 ml/min. The solvent delay was 2 min and diluted samples of 1 µL were injected automatically using Autosampler AS1300 coupled with GC in the split mode. EI mass spectra were collected at 70 eV ionization voltages over the range of m/z 50–650 in full scan mode. The ion source temperature was set at 200 °C. The components were identified by comparison of their mass spectra with those of WILEY 09 and NIST 14 mass spectral database [37]. Xcalibur 3.0 data system in the GC–MS with its threshold values was used to confirm that all the mass spectra of the identified compounds were attached to the library. Furthermore, the measurement match factor (MF) with values ≥ 650 was used to confirm the identified compounds [38].

All analyses of studied samples have been done using Thermo Fisher GC–MS, which is supported by a number of mass spectral libraries, and all separated compounds have been identified and all data have been reported using NIST014, which is already supported by retention index (RI) library for 82,868 compounds (https://www.nist.gov/system/files/documents/srd/NIST1aVer22Man.pdf) [39, 40].

2.4 Methanol extracts

Leaves from the three tree species (C. citriodora, Cup. macrocarpa, and S. cumini) were air-dried at room temperature for 1 week, thin cut to small sizes or particles using a small laboratory mill. Approximately 50 g of each leaf sample was soaked in about 100 mL of methanol solvent in a conical flask for 1 week and then filtered through a cotton plug and Whatman no. 1 filter paper. The solvent evaporated as the extract was poured into Petri dishes to complete the dryness and then concentrated [41]; then, the methanol leaf extracts (MLEs) were obtained. The yields of the methanol extracts were 8.2, 6.6, and 9.12 g/100 g air-dry leaves from C. citriodora, Cup. macrocarpa, and S. cumini, respectively.

2.5 HPLC analysis of phenolic compounds

For the phytochemical analysis, the phenolic compounds from the MEs of C. citriodora, Cup. macrocarpa, and S. cumini leaves were identified by HPLC (Agilent 1100). The instrument was composed of a binary LC pump, a UV/Vis detector, and a C18 column (125 mm × 4.60 mm, 5-µm particle size) [42]. The Agilent Chem-Station was used to acquire and analyze chromatograms. A gradient mobile phase of two solvents—Solvent A (MeOH) and Solvent B [acetic acid in H2O (1:25)]—was used to separate phenolic acids. The gradient program began with 100% B and remained there for 3 min. This was followed by 5 min of 50% eluent A, 2 min of 80% eluent A, 5 min of 50% eluent A, 2 min of 80% eluent A, 5 min of 50% eluent A, 5 min of 50% eluent A, and 5 min of detection wavelength at 250 nm. As a result, the phenolic components were arranged in order to authenticate standard components by this mobile phase.

2.6 Antifungal activity of wood-treated essential oils and leaf methanol extracts

Air-dried Scots pine (Pinus sylvestris L.) sapwood was used for the treatment with the EOs and the MEs. The identification of wood was performed by academicals staff in the Forestry and Wood Technology Department, Faculty of Agriculture, Alexandria University using softwood key identification [43]. Microscopic cross section was examined (Fig. 1).

Fig. 1
figure 1

Cross section of Pinus sylvestris wood sample. RC resin canal, EW earlywood tracheids, LW latewood tracheids

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The EOs were prepared at the concentrations of 0, 6, 12, 25, and 50 mg/L, while the MEs were prepared at 0, 500, 1000, and 4000 mg/L by dissolving the respective amount in dimethylsulfoxide (DMSO 10%), and a few drops of Tween 80 was added for the concentrated EOs. Air-dried Scots pine sapwood blocks with dimensions of 0.5 cm × 2 cm × 2 cm were autoclaved at 121 °C for 20 min, then treated with the prepared concentrations of EOs and MEs (each block has received a 100 μL). The fungus Fusarium solani MW947256 was assayed for linear growths as incubated with the treated woods in the incubator chamber at 20–25 °C with relative humidity 85–92% for 7 days; then, the percentage of mycelial growth inhibition was measured with the following formula [44]: MGI = [(Ac − At) / Ac] × 100; where MGI is mycelial growth inhibition and AC and AT are average diameters of the fungal colony of the control and treatment, respectively. Wood samples soaked only with 10% DMSO were used as the negative control. Positive control of azoxystrobin + difenoconazole (1000 mg/L) was also employed.

2.7 Statistical analysis

The obtained data from the antifungal activity of essential oils and methanol extracts from the leaves of the three trees with their concentrations were analyzed using CoStat software version 6.303 [45], in split-plot design. The factor concentrations were set as the main plot, while the factor EOs or MEs as well as the interactions between the source and concentrations of EOs or MEs. The least significant difference at 0.05 level of probability was used for comparison between the means [46].

3 Results

3.1 Chemical compositions of the essential oils

Table 1 and Fig. 2 present the chemical compounds identified in the essential oil (EO) from Corymbia citriodora. The main compounds were citronellal (23.95%), citronellol (9.80%), p-cymene (9.32%), spathulenol (9.29%), isopulegol (5.38%), crypton (4.65%), citronellol epoxide (4.45%), neoisopulegol (3.67%), citronellic acid (2.96%), eucalyptol (2.7%), 4-terpinenol (2.36%), citronellol acetate (2%), trans-3-nonen-2-one (1.48%), and cuminaldehyde (1.21%).

Table 1 Chemical constitutes of the essential oil from Corymbia citriodora
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Fig. 2
figure 2

GC–MS chromatograms of the identified essential oils from leaves of a C. citriodora; b Cup. macrocarpa; c S. cumini

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The chemical constituents of the EO from Cupressus macrocarpa leaves are shown in Table 2. The main abundant compounds were sabinene (11.94%), 4-terpinenol (11.34%), citronellol (9.59%), citronellal (9.85%), p-cymene (7.67%), spathulenol (5.24%), γ-terpinene (5.05%), camphor (4.31%), limonene (3.2%), α-terpinene (2.89%), β-mmyrcene (2.64%), 15-kaurene (2.4%), terpinolene (2.32%), sclareol (1.86%), linalool (1.61%), α-terpineol (1.53%), farnesol (1.48%), crypton (1.32%) and α-thujene (1.03%).

Table 2 Chemical constitutes of the essential oil from C. macrocarpa
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Table 3 shows the chemical compounds of the EO from Syzygium cumini leaves. The main compounds were trans-β-ocimene (19.11%), α-pinene (18.79%), caryophyllene (9.30%), (Z)-β-ocimene (8.16%), limonene (6.00%), humulene (4.69%), β-pinene (4.01%), α-terpineol (3.79%), bornyl acetate (2.88%), myrcene (2.26%), citronellal (1.79%), 2,2,4a,7a-tetramethyldecahydro-1H-cyclobuta[e]inden-5-ol (1.76%), caryophyllenyl alcohol (1.63%), globulol (1.62%), terpinen-4-ol (1.62%), caryophyllene oxide (1.54%), and citronellol (1.33%).

Table 3 Chemical constitutes of the essential oil from S. cumini leaves
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3.2 Phenolic compounds

Results from Table 4 and Fig. 3 show the identified phenolic compounds in the methanol leaf extracts (MLEs) of C. citriodora (Fig. 2a), Cup. macrocarpa (Fig. 2b), and S. cumini (Fig. 2c). Benzoic acid (8.11 μg/g), gallic acid (7.96 μg/g), ellagic acid (5.78 μg/g), caffeic acid (4.65 μg/g), and catechol (3.75 μg/g) were the most abundant compounds in the MLE of C. citriodora. The abundant phenolic compounds in the MLE from Cup. macrocarpa were syringic acid (7.59 μg/g), catechol (6.85 μg/g), gallic acid (6.78 μg/g), and chlorogenic acid (4.62 μg/g). In the MLE of S. cumini, the most abundant compounds were cinnamic acid (10.66 μg/g) caffeic acid (9.87 μg/g), and ellagic acid (8.76 μg/g).

Table 4 Phenolic compounds (μg/g) by HPLC in the methanol leaf extracts from C. citriodora, Cup. macrocarpa and S. cumini
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Fig. 3
figure 3

HPLC chromatograms of the identified phenolic compounds in the methanol leaf extracts from C. citriodora (a), Cup. macrocarpa (b), and S. cumini (c)

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3.3 Antifungal activity of essential oils and methanol extracts against Fusarium solani

The antifungal activity of Scots pine treated with EOs and MLE against the growth of Fusarium solani is visually observed in Figs. 4, 5, and 6. The growth of the fungus mycelium was inhibited as EO or MLE concentrations were increased, compared to the positive control of azoxystrobin + difenoconazole (1000 mg/L), which caused 100% inhibition to F. solani.

Fig. 4
figure 4

Cup. macrocarpa leaf EO (Ca) and leaf extract (Cb) treated Scots pine sapwood blocks against the growth of F. solani. Control: 10% DMSO; positive control: azoxystrobin + difenoconazole (1000 mg/L)

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Fig. 5
figure 5

C. citriodora leaf essential oil (Ea) and leaf extract (Eb) treated Scots pine sapwood blocks against the growth of F. solani

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Fig. 6
figure 6

S. cumini leaf essential oil (Ja) and leaf extract (Jb) treated Scots pine sapwood blocks against the growth of F. solani

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Figure 7 illustrates the main impacts of EO concentration and source on F. solani development. The percentage of fungal mycelial growth inhibition increased as the concentrations rose. Additionally, Cup. macrocarpa EO was shown to have the highest overall impacts of any EO source. Table 5 shows the proportion of F. solani mycelial growth that was inhibited (%) when wood was treated with different EO doses. The wood-treated Cup. macrocarpa EO at 50 and 25 mg/L, respectively, showed the highest levels of inhibition (65.71% and 35.71%) against the growth of F. solani. Additionally, S. cumini EO and C. citriodora EO both inhibited F. solani at 50 mg/L (35.71% and 35.23%, respectively). Additionally, moderate activity was found when the EO from Cup. macrocarpa EO was applied at 12 mg/L with an inhibition value of 28.57%, and from C. citriodora EO with a value of 22.85% at 25 mg/L.

Fig. 7
figure 7

The main effects of essential oil concentration and source on the growth of F. solani

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Table 5 Fungal mycelia inhibition percentages of Cup. macrocarpa, C. citriodora, and S. cumini leaf essential oils
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The main impacts of MLE concentration and their sources on F. solani growth were displayed in Fig. 8. It is evident that fungal inhibition (%) increased as MLE concentration rose. Furthermore, out of all the examined extracts, S. cumini MLE displayed the highest overall inhibition. Table 6 displays how MLEs applied to wood inhibited the fungal mycelium growth of F. solani. It is interesting to note that S. cumini MLE at a concentration of 4000 mg/L when applied to wood samples demonstrated the highest level of inhibition (92.85%), followed by Cup. macrocarpa MLE (70%). The wood samples treated with C. citriodora MLE at 4000 mg/L (49.52%), 2000 mg/L (41.90%), Cup. macrocarpa MLE (37.14%), and S. cumini MLE (35.71%) at 2000 mg/L showed good efficacy against the growth of F. solani as well.

Fig. 8
figure 8

The main effects of methanol extract concentration and source on the growth of F. solani

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Table 6 Fungal mycelia inhibition percentages of Cup. macrocarpa, C. citriodora, and S. cumini leaf extracts
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4 Discussion

The EOs and phenolic compound profiles from the leaves of three Egyptian-grown trees Corymbia citriodora, Cupressus macrocarpa, and Syzygium cumini were examined in the current study using chromatographic equipment for GC–MS and HPLC. When applied to wood samples, the bioactivities against the growth of Fusarium oxysporum were likewise documented with varying degrees of inhibition.

C. citriodora EO demonstrated the existence of citronellal, citronellol, p-cymene, spathulenol, isopulegol, crypton, citronellol epoxide, neoisopulegol, citronellic acid, eucalyptol, 4-terpinenol, citronellol acetate, trans-3-nonen-2-one, and cuminaldehyde as major components. Citronellal (78%) was the main component for C. citriodora EO grown in Portugal [47], while citronellal (83.5%) was found as the predominant compound in the EO from the collected plant from Benin [48]. The EO of E. citriodora, which yielded 1.73%, showed strong inhibition for the radial growth of F. oxysporum f. sp. lycopersici, Alternaria triticina, Rhizoctonia solani, Macrophomina phaseolina, Colletotrichum lindemuthianum, Helminthosporium oryzae, and Alternaria solani [49]. The Algerian E. citriodora leaf EO showed the presence of dominant compounds citronellal (69.77%), citronellol (10.63%), and isopulegol (4.66%) with potent antifungal activity against Microsporum canis, Trichophyton mentagrophytes, and T. rubrum [50].

E. citriodora were citronellal (40%), isopulegol (14.6%), and citronellol (13%) grown in Colombia [51]. With percentages of 61.78%, 15.54%, and 7.90%, citronellal, isopulegol, and -citronellol were the principal components of the EO of C. citriodora. The EO and citronellal had a significant negative impact on the growth of Pyricularia grisea, Aspergillus spp., and Colletotrichum musae [52]. Citronellal (52.2%), citronellol (12.3%), and isopulegol (11.9%) were the three main compunds of the 0.6% EO obtained from the leaves of the lemon-scented eucalyptus (Eucalyptus citriodora) collected from the campus of the Anjab University in Chandigarh, India [53]. Citronellal (67.5%), citronellol (6.9%), and menthol (6.1%), according to a chromatographic examination of C. citriodora EO from Brazil, were the main constituents [54].

Methanolic extract of E. citriodora had the highest antimycotic efficacy against four Aspergillus spp., with a value of 14.5% followed by EO (12.9%), chloroform extract (10.15%), and aqueous extract (10%) [10]. Flavonoid glycoside, citrioside C, kaempferol-3-O-β-d-glucopyranosyl (12)-α-l-rhamnoside, kaempferol-3-O-α-l-rhamnoside, and quercetin-3-O-α-l-rhamnoside were isolated from leaves of E. citriodora [55]. 8-[1-(p-hydroxyphenyl)ethyl]rhamnocitrin, cinnamic acid, p-coumaric acid, caffeic acid (4), and gallic acid were isolated from the kino of E. citriodora [56]. The flavonoids sakuranetin, narigenin, aromadendrin 7-methyl ether, aromadendrin, kaempferol 7-methyl ether, gallic acid, the glycosides 1-O-cinnamoyl-6-O-(p-coumaroyl)-β-D-glucopyranoside, 7-methylaromadendrin-4’-O-(6’’-trans-p-coumaroyl)-β-D-glucopyranoside, 6-O-(p-coumaroyl)-D-glucopyranoside, and the tannin 1-O-2,O-digalloyl-6-O-(p-coumaroyl)-β-D-glucopyranoside were isolated from E. citriodora [11].

The main compounds found in Cupressus macrocarpa leaves’ EO included sabinene (11.94%), 4-terpinenol (11.34%), citronellol (9.59%), citronellal (9.85%), p-cymene (7.67%), spathulenol (5.24%), γ-terpinene (5.05%), camphor (4.31%), and limonene (3.2%). Neral (31–35%), hydroxy citronellal (12–16%), geraniol (3–4%), trans-piperitol (7–8%), isobornyl isobutrate (0.7–6.61%), linalool (0.6–5.21%), terpinyl acetate (0.10–3.27%), and myrcene (0.22–2.60%) were the major components in Cup. macrocarpa EOs of fresh and dried leaves [57].

From the extract of Cup. macrocarpa, several bioactive substances were isolated, including gallic acid, cupressuflavone, sandaracopimaric acid, blumenol-C-glucoside, β-sitosterol, 3-methylbut-3-en-1-ol-O-b-D-glucopyranoside, 3’-demethoxy-dihydrodehydrodiconiferyl alcohol-9’-O-a-Lrhamnopyranoside, agathadiol, protocatechuic acid, and shikimic acid, which they observed antibacterial activity against Staphylococcus aureus [58]. A leaf extract from Cup. macrocarpa was analyzed using LC–ESI–MS/MS, which revealed 49 compounds, including (-)-shikimic acid, D-(-)-quinic acid, myricetin, p-coumaric acid, rhoifolin, quercetin, kaempferol derivatives, naringenin-7-O-glucoside, and luteolin-3,7-di-O-glucoside [59]. The extract from Cup. macrocarpa contained the polyphenolic substances gallic acid, catechol, p-hydroxy benzoic acid, caffeine, chlorogenic, vanillic acid, caffeic acid, syringic acid, vanillin, p-coumaric acid, ferulic acid, benzoic acid, hyperoside rose, ellagic acid, O-coumaric acid, salicylic acid, myricetin, and quercitin [60].

Trans-β-ocimene (19.11%), α-pinene (18.79%), caryophyllene (9.30%), (Z)-β-ocimene (8.16%), and limonene (6.00%) were the primary constituents of the EO from Syzygium cumini leaf EO. Pinocarveol, α-terpeneol, myrtenol, eucarvone, muurolol, myrtenal, geranylacetone, α-cadinol, and pinocarvone were previously revealed by S. cumini EO [61]. α-Pinene, β-pinene, trans-caryophyllene, 1,3,6-octatriene, Δ-3-carene, α-caryophyllene, and α-limonene were presented as the main compounds in EO from leaves of S. cumini [62]. While another study showed that α-pinene, (Z)-β-ocimene, and (E)-β-ocimene were the main compounds [26]. The majority of the sesquiterpene components, including terpineol, α-caryophyllene, and β-caryophyllene, were identified in S. cumini EO [27].

It was demonstrated that the content of β-pinene and β-caryophyllene in the EO was associated with its antiinflammatory properties [63]. It was shown that S. cumini EO has antihyperlipidemic, antiallergic, and good antibacterial activity against bacteria, fungi, and protozoa parasites of the species Leishmania and Trypanosoma [64]. In comparison to methylene chloride extract and EO, the methanol extract showed more action against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Neisseria gonorrhoeae, Bacillus subtilis, and Enterococcus faecalis [62]. These might be connected to the methanolic extract’s increased total phenolic and flavonoid concentration when compared to other extracts. The EO of leaves from S. cumini showed moderate activity against E. coli and the main component was α-pinene (53.21%) [65].

The primary ingredient concentrations in the EOs of S. cumini, C. citriodora, and C. macrocarpa were different from those described in the literature. These variations in EO compositions could result from a variety of environmental (climatic, seasonal, or geographical) and genetic variations [66,67,68,69]. Additionally, it should be taken into account that the synergistic interactions between the various EO components may contribute to the activity of them. Previously, it was shown that the citronellal and linalool in Cymbopogon nardus EO synergized to provide a potent antifungal action [70].

The major chemical constituent citronellal may be responsible for the activity against fungal growth. Citronellal is reported to show activities against fungi from Aspergillus [70]. Citronellal was observed to have a strong effect on the growth of A. niger [71], while other compounds like α-pinene, β-pinene, myrcene, geraniol, and linalool have antifungal activity [70].

Ferulic and p-coumaric acids showed significantly enhanced inhibitory potential in a synthetic media; ferulic acid remained active against Monilinia fructicola and Alternaria alternata, and it surpassed p-coumaric acid in suppressing Botrytis cinerea [72]. The most effective antifungal agents were caffeineic, 2,3,4-trihydroxybenzoic, p-coumaric, and protocatechuic acids, which virtually completely suppressed A. alternata on both early- and late-ripening sweet cherry [73]. Additionally, p-coumaric acid completely stopped Fusarium from growing. Conversely, at the same dose of 1000 μg/g, ferulic acid inhibited 64% of Fusarium mycelial development and was especially effective against B. cinerea growth [74, 75].

5 Conclusion

This study looked into the chemical composition and antifungal properties of methanol extracts (MEs) and essential oils (EOs) derived from the leaves of three trees grown in Egypt: Corymbia citriodora, Cupressus macrocarpa, and Syzygium cumini. GC–MS was used to identify the chemical components of EOs, while HPLC was used to identify the chemical components of MEs. Trials evaluating the obtained EOs and MEs’ antifungal efficacy against Fusarium solani were conducted when applied to wood samples. For the studied EOs and MEs, distinct and significant inhibitory effects were seen. However, additional research is needed to assess the toxicity and the efficacy of treatment for long-term as antifungal agents before the acquired EOs and MLEs can be used as substitutes for synthetic fungicides.