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Ginger ( Zingiber officinale ), a globally distributed plant, is widely used in the industry for its flavourings, seasonings, and beverages. However, maintaining its quality and volatile components during processing has posed a challenge. This study, therefore, aimed to assess the impact of drying time (24, 48, and 72h) in a circulation oven at 40 °C on the chemical composition and yield of fresh and dried ginger. The essential oils were extracted using the hydrodistillation method, and their chemical analysis was conducted using gas chromatography. The drying time in the oven directly influenced the essential oil yield, with a longer time resulting in a higher yield. We identified 27 compounds in the essential oils, varying their predominance depending on the drying time. The PCA analysis revealed that the drying time can lead to the formation of different chemotypes for ginger, indicating that altering the drying time can yield significantly different chemical profiles.

Strawberry is a food rich in bioactive compounds with great antioxidant potential. However, due to the high incidence of pests that affect crop cultivation, phytosanitary management still lacks control methods for agroecological cultivation. Thus, the present research aimed to evaluate the chemical composition and the potential of the essential oil of the leaves of Piper macedoi in the control of Cerosipha forbesi in laboratory and semi-field conditions. The concentration of essential oil in the leaves of P. macedoi that showed the highest mortality was 2.0 ml/L of oil, with a mortality above 91% under laboratory conditions. A mortality rate of 80% for all concentrations tested was observed after 24 h in all conditions tested. Thus, using essential oil from the leaf of P. macedoi can be a highly viable strategy in managing the aphid C. forbesi since it showed high mortality rates with small doses of oil.

Among the several terpenes existing in nature, Citronellal, a monoterpene aldehyde, deserves to be highlighted for its biological properties that have been pointed out in numerous studies. This work aimed to conduct a literature review on its biological properties. Citronellal is a prominent compound in the essential oils of Cymbopogon genus plants. Apart from being employed as a fragrance ingredient in aromas, fragrances, and cosmetics, it is also used as an intermediate in synthesising (-)-menthol. Various studies have demonstrated Citronellal's potential as an antibacterial compound, particularly anti- Staphylococcus and Escherichia bacteria. Citronellal also has antifungal properties against several fungi, especially fungi of the genus Candida . The studies found showed that Citronellal also has insecticidal, acaricidal, antiparasitic, anaesthetic, antiviral, antioxidant, antinociceptive, cardioprotective, antihypertensive, anti-inflammatory, antidiabetic, and anticancer properties.

Tetranychus urticae , popularly known as spider mite, is a pest that causes several economic losses to crops. Thus, this work evaluated the effect of essential oils from the leaves of Piper macedoi and Piper arboreum on managing T. urticae . The chemical compounds present in essential oils were identified by gas chromatography. Tests were carried out to evaluate the acaricidal activity by fumigation effect and direct contact with T. urticae . The results showed that LC 50 values for the essential oils of P. macedoi and P. arboreum in the fumigation effect were 16.15 and 50.53 µL L -1 air, respectively. Using the contact application route, the LC 50 values for the essential oil of P. macedoi was 17.16 µL mL -1 , and for P arboreum , it was 15.17 µL mL -1 . So, this work showed that essential oils of Piper macedoi and Piper arboreum could be used as possible alternative to managing T. urticae.

The Croton genus is known for its various biological properties, which inspired this study to investigate the anti-bacterial pro-perties and chemodiversity of the essential oils of three Croton species: Croton blanchetianus , Croton jacobinensis , and Croton nepetifolius . The essential oils were characterised by gas chromatography (GC-MS) and demonstrated anti-bacterial activity against Staphylococcus aureus and Escherichia coli using the disc diffusion method. The essential oil composition of C. blanchetianus showed bicyclogermacrene (16.04%) and spathulenol (16.44%) as the main compounds. In C. jacobinensis , bicyclogermacrene (22.04%), caryophyllene (17.95%), and β-phellandrene (12.30%) were the most prevalent. Meanwhile, C. nepetifolius's essential oil consisted mainly of bicyclogermacrene (17.69%), caryophyllene (15.15%), and germacrene D (11.78%). The principal component analysis (PCA) results showed three distinct chemotypes for each Croton species, suggesting that they have well-defined and unique chemical profiles. Interestingly, the three Croton species demonstrated activity only against Staphylococcus aureus bacteria.

Tomato is one of the most produced and consumed fruits in the world. However, it is a crop that faces several phytosanitary problems, such as fusarium wilt, caused by Fusarium oxysporum . Thus, this study aimed to evaluate citronella and melaleuca essential oils in vitro potential in the fungus F. oxysporum management. The chemical identification of the components in the essential oils was performed by gas chromatography with flame ionization and mass spectrometer detectors. The IC 50 and IC 90 were determined by linear regression and the percentage of inhibition of the fungus by analysis of variance. The major compounds in citronella essential oil were citronellal, Geraniol, and citronellol; in melaleuca (tea tree) oil were terpinen-4-ol and α-terpinene. Both oils promoted more significant inhibition at concentrations of 1.5 and 2.5 μL/mL, besides not presenting significant differences with commercial fungicides, confirming the high potential for using this control method in agriculture.

Cutaneous and visceral leishmaniasis are public health problems in Africa, Asia, Europe, and America. The treatment has a high cost and toxicity. Thus, this work aims to evaluate the leishmanicidal activity of alpha-bisabolol and its three synthetic derivatives, P1, P2, and P3, on the promastigotes and amastigotes Leishmania infantum and L. amazonensis forms. Alpha-bisabolol showed the lowest IC 50 with 3.43 for L. amazonensis promastigotes, while P1 was the most toxic for L. infantum with an IC 50 of 9.10. The derivative P3 was better for the amastigote form, with an IC 50 of 3.39 for L. amazonensis . All the compounds effectively decreased the intracellular load of amastigote and its ability to turn promastigote again. Thus, alpha-bisabolol and its three synthetic derivatives were effective in their leishmanicidal activity. Therefore, it can be an option for developing new treatments against leishmaniasis.

Two-spotted spider mite causes significant damage to various crops, often requiring synthetic acaricides for their control. However, the frequent use of these products causes several environmental problems. Thus, this work aimed to evaluate the acaricidal action, using the application by fumigation on female adults of Tetranychus urticae of essential oil from the leaves of Rosmarinus officinalis L., and its major compound, α -pinene. In addition, the essential oil was characterized by gas chromatography and mass spectrometry. α -pinene was the compound with the highest relative area in the oil (29.2%). In fumigation tests, α-pinene showed more significant toxicity than rosemary essential oil on two-spotted spider mite females with LC 50 and LC 90 values of 1.58 and 49.61 µL/L air, showing the impact of the chemical composition of the essential oil on the biological activity.