Analyses of organ specific variations in essential oils of fourOcimumspecies

Sweet Basil (Ocimum basilicum L.)-A Review of Its Botany, Phytochemistry, Pharmacological Activities, and Biotechnological Development

An urgent demand for natural compound alternatives to conventional medications has arisen due to global health challenges, such as drug resistance and the adverse effects associated with synthetic drugs. Plant extracts are considered an alternative due to their favorable safety profiles and potential for reducing side effects. Sweet basil (Ocimum basilicum L.) is a valuable plant resource and a potential candidate for the development of pharmaceutical medications. A single pure compound or a combination of compounds exhibits exceptional medicinal properties, including antiviral activity against both DNA and RNA viruses, antibacterial effects against both Gram-positive and Gram-negative bacteria, antifungal properties, antioxidant activity, antidiabetic potential, neuroprotective qualities, and anticancer properties. The plant contains various phytochemical constituents, which mostly consist of linalool, eucalyptol, estragole, and eugenol. For centuries, community and traditional healers across the globe have employed O. basilicum L. to treat a wide range of ailments, including flu, fever, colds, as well as issues pertaining to digestion, reproduction, and respiration. In addition, the current research presented underscores the significant potential of O. basilicum-related nanotechnology applications in addressing diverse challenges and advancing numerous fields. This promising avenue of exploration holds great potential for future scientific and technological advancements, promising improved utilization of medicinal products derived from O. basilicum L.

Repellence and fumigant toxicity of essential oils of Ocimum gratissimum and Ocimum kilimandscharicum on Tuta absoluta (Lepidoptera: Gelechiidae)

Tuta absoluta Meyrick originates in South America and is now one of the most important insect pests of Solanaceae in different parts of the world, including Africa. Its control has relied primarily on chemical insecticides, which are associated with negative ecological effects. In the present study, essential oils of Ocimum gratissimum and O. kilimandscharicum were tested for repellence and fumigant toxicity on the adult stages under laboratory conditions. The oil of O. gratissimum was more repellent, but its toxicity was comparable with that of O. kilimandscharicum. The major constituents of O. gratissimum were methyl eugenol (39.5%) and eugenol (29.7%). Those of O. kilimandscharicum were camphor (47.1%) and 1.8-cineole (19.3%). Eugenol (LC₅₀ of 0.24 μl/ml, 83.3%, RI₅₀ = 0.15) and camphor (LC₅₀ of 0.23 μl/ml, 89.5%, RI₅₀ = 0.13) were more toxic (at 1 μl/ml for 24 h) and repellent than the other constituents. The results show potential of the essential oils for use in integrated management of the tomato pest.

One Hundred Faces of Geraniol

Geraniol is a monoterpenic alcohol with a pleasant rose-like aroma, known as an important ingredient in many essential oils, and is used commercially as a fragrance compound in cosmetic and household products. However, geraniol has a number of biological activities, such as antioxidant and anti-inflammatory properties. In addition, numerous in vitro and in vivo studies have shown the activity of geraniol against prostate, bowel, liver, kidney and skin cancer. It can induce apoptosis and increase the expression of proapoptotic proteins. The synergy of this with other drugs may further increase the range of chemotherapeutic agents. The antibacterial activity of this compound was also observed on respiratory pathogens, skin and food-derived strains. This review discusses some of the most important uses of geraniol.

Antifungal activity, mode of action and anti-biofilm effects of Laurus nobilis Linnaeus essential oil against Candida spp

OBJECTIVE

The present study demonstrated the antifungal potential of the chemically characterized essential oil (EO) of Laurus nobilis L. (bay laurel) against Candida spp. biofilm adhesion and formation, and further established its mode of action on C. albicans.

METHODS

L. nobilis EO was obtained and tested for its minimum inhibitory and fungicidal concentrations (MIC/MFC) against Candida spp., as well as for interaction with cell wall biosynthesis and membrane ionic permeability. Then we evaluated its effects on the adhesion, formation, and reduction of 48hC. albicans biofilms. The EO phytochemical profile was determined by gas chromatography coupled to mass spectrometry (GC/MS).

RESULTS

The MIC and MFC values of the EO ranged from (250 to 500) μg/mL. The MIC values increased in the presence of sorbitol (osmotic protector) and ergosterol, which indicates that the EO may affect cell wall biosynthesis and membrane ionic permeability, respectively. At 2 MIC the EO disrupted initial adhesion of C. albicans biofilms (p<0.05) and affected biofilm formation with no difference compared to nystatin (p>0.05). When applied for 1min, every 8h, for 24h and 48h, the EO reduced the amount of C. albicans mature biofilm with no difference in relation to nystatin (p>0.05). The phytochemical analysis identified isoeugenol as the major compound (53.49%) in the sample.

CONCLUSIONS

L. nobilis EO has antifungal activity probably due to monoterpenes and sesquiterpenes in its composition. This EO may affect cell wall biosynthesis and membrane permeability, and showed deleterious effects against C. albicans biofilms.