Antimicrobial Activity and Gas Chromatography-Mass Spectrometry (GC-MS) Analysis of Saudi Arabian Ocimum basilicum Leaves Extracts

Bio-active compounds and major biomedical properties of basil (Ocimum basilicum, lamiaceae)

Due to the numerous health benefits and therapeutic properties, herbs and plant metabolites/extracts are gaining popularity. This is particularly evident in the current era of drug resistance and the adverse effects of chemical drugs. Ocimum basilicum, also known as basil, has been extensively studied for its pharmacological benefits, including antimicrobial, antifungal, antioxidant, anti-inflammatory, antiviral, and wound healing properties. As a result, this plant has the potential to treat a wide range of diseases in both humans and animals. Ocimum basilicum contains various bioactive chemical compounds, such as neryl acetate, 1,8-cineole, p-allylanisole, geraniol, methyl eugenol, methyl chavicol, and trans-α-bergamotene. The latest advancements in technology can be utilised to enhance the beneficial properties of raw Ocimum basilicum extract. This review compiles and presents the profile of phytocomponents and pharmacological properties of Ocimum basilicum. The findings presented here will contribute to further research on this remarkable herb, aiming to develop effective pharmaceutical solutions for various health issues in humans and animals.

Antimicrobial and Other Pharmacological Properties of Ocimum basilicum, Lamiaceae

Since ancient times, various scientists and doctors have utilized different herbs to heal diseases. Due to the rise in drug resistance and the negative effects of chemosynthetic drugs, researchers and the general public around the world have become more interested in medicinal herbs and plant metabolites/extracts. This is due to its non-toxicity and its several health benefits when used to treat diseases in clinical and medical settings. Ocimum basilicum is one such plant, possessing a wide range of bioactive phytochemicals including alkaloids, phenolics, flavonoids, tannins, saponins, reducing sugars, cardiac glycosides, steroids and glycosides, as well as complex pharmacological activities, including anti-inflammatory, antifungal, antibacterial, antioxidant, wound healing and antiviral properties. The results of many studies on Ocimum basilicum plant extracts are collected and presented in this review. The plant extracts have excellent potential to be used as medicinal raw materials, and exhibit an extensive variety of therapeutic capacities, including antibacterial, antioxidant, wound healing, anti-inflammatory, antifungal, and antiviral properties.

In vitro anticandidal activity and gas chromatography-mass spectrometry (GC-MS) screening of Vitex agnus-castus leaf extracts

Background

Candida infections are becoming more drug resistant; it is necessary to search for alternative medications to treat them. Therefore, the present study estimates the anticandidal activity of Vitex agnus-castus (VA-C) leaf extracts.

Methods

We used the agar well diffusion method to assess the anticandidal activity of three different VA-C leaf extracts (ethanol, methanol, and water) against three Candida species (Candida tropicalis, Candida albicans, and Candida ciferrii). The minimum inhibitory concentration (MIC) was estimated using the two-fold dilution method and the minimum fungicidal concentration (MFC) was determined using the classic pour plate technique. The MFC/MIC ratio was calculated to estimate the microbicidal or microbiostatic activity. A gas chromatography mass spectrometer was used to screen the phytochemicals of the VA-C leaf extracts (ethanol, methanol, and water).

Results

All VA-C extracts ethanol, methanol, and water were significantly inhibited the growth of the test Candida species and the inhibition activity depended on the solvent used and the Candida species. The results showed that C. tropicalis was the most highly inhibited by all extracts followed by C. albicans and C. ciferrii. The MIC values were 12.5–25 µg/ml, and MFC values were 25–100 µg/ml. The ratios of MFC/MIC were two-fold to four-fold which was considered candidacidal activity. Ninety-five phytochemical compounds were identified by the GC-MS assay for the VA-C leaf extracts. The total number of compounds per extract differed. Methanol had 43 compounds, ethanol had 47 compounds, and water had 52 compounds. The highest compound concentrations were: 4,5-Dichloro-1,3-dioxolan-2-one in ethanol and methanol, 1H-Indene, 2,3-dihydro-1,1,2,3,3-pentamethyl in ethanol, Isobutyl 4-hydroxybenzoate in methanol, and Benzoic acid and 4-hydroxy- in water. These phytochemical compounds belong to different bioactive chemical group such as polyphenols, fatty acids, terpenes, terpenoids, steroids, aldehydes, alcohols, and esters, and most of which have anticandidal activity.

Conclusions

VA-C leaf extracts may be useful alternatives to anticandidal drugs, based on their effectiveness against all test Candida species at low concentrations. However, appropriate toxicology screening should be conducted before use.

The Effect of Nitrogen Input on Chemical Profile and Bioactive Properties of Green- and Red-Colored Basil Cultivars

In the present study, three red-colored (Dark Opal, Basilico Rosso, and Red Basil) and one green-colored landrace (Mitikas) of basil (Ocimum basilicum L.) were grown under four nitrogen regimes, namely Control (no fertilizer added), 200 ppm, 400 ppm, and 600 ppm of nitrogen (N). Fresh yield varied depending on N input following a quadratic function in all four genotypes, and green basil performed better compared to the red cultivars. A significant interaction of genotype × N input was recorded for most of the chemical parameters measured. Tocopherols contents of leaves were consistently higher in plants that received 200 ppm of N and lower in those receiving 600 ppm of N, especially in Dark Opal and Red Basil cultivars. Polyunsaturated fatty acids (PUFA) were the major category of fatty acids and Red Basil had the lowest ratio of omega-6/omega 3 (0.29) and thus the best fatty acid profile. Polyphenols content was the highest in Red Basil and Dark Opal (25 mg/g of extract on average) and the lowest in Mitikas and decreased with increasing N input. Similarly, antioxidant activity was the highest in Dark Opal and Red Basil fertigated with 200 ppm of N, whereas all the leaf extracts tested had good antibacterial and antifungal activity. In conclusion, basil chemical and bioactive profile was significantly influenced by both genotype and N input. Red-colored basil, although less productive, had the best chemical profile, and moderate levels of N input may provide the best compromise between yield, nutritional value, and bioactivity for the species.