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Antifungal effect of thymol, thymoquinone and thymohydroquinone against yeasts, dermatophytes and non-dermatophyte molds isolated from skin and nails fungal infections
Abstract
Several human pathogenic fungi can acquire resistance against
the available antifungal compounds or need prolonged time of
therapy, which may cause toxicity. Thymol, thymoquinone (TQ) and
thymohydroquinone (THQ) are principle constituents of the essential
oil of Nigella sativa seeds. TQ and THQ were organically synthesized
from thymol in our laboratory. The chemical structure and purity were
confirmed by using GC-MS analysis. The three compounds were
primary tested at concentration of 1mg/ ml for their preliminary
antifungal effect against thirty human pathogens isolated from
patients. The tested pathogens were eleven dermatophyte, eight yeast
and eleven mold isolates. All of the three compounds showed 100%
inhibition for the thirty pathogens at concentration of 1mg/ ml. The
minimum inhibitory concentration (MIC) test of each compound was
studied on eight dermatophyte, five yeast and five mold isolates.
Thymoquinone was the best antifungal compound against all of the
tested dermatophytes and yeasts, followed by thymohydroquinone and
thymol respectively. Thymol was the best antifungal against molds
followed by TQ and THQ respectively.
... Te oil also treats respiratory conditions such as asthma, emphysema, and bronchitis [4]. Several fndings reported that black cumin has diferent pharmacological activities such as antioxidant [5], antidiabetic [6], antifungal [7][8][9][10][11], antiviral [12][13][14][15], antiparasitic [16][17][18][19], anticancer [20], and antibacterial [21]. ...
Black cumin (Nigella sativa L.) seeds essential oil compositions (EOCs) have been used for their medicinal and aromatic values across the world since ancient times. Studies have revealed the presence of variability among black cumin genotypes in EOCs. In Ethiopia, few studies have been conducted to explore the variability of black cumin genotypes by using EOCs. This study investigated the variability of Ethiopian black cumin genotypes (EBCGs) by EOCs. Seeds of 64 N. sativa genotypes were used for this experiment. Composite samples of 100 g of seeds were collected and roughly ground from each genotype. The extraction was made by hydrodistillation using a Clevenger-type apparatus for 3 h, and the essential oil was collected by measuring the amount using a measuring pipette. The essential oil samples were stored in a refrigerator at 4°C until gas chromatography–mass spectrometry (GC-MS) analysis. Descriptive statistics was used to estimate the variations among populations’ combined mean values of EOCs using the SAS version 9.4 software package. The correlation and hierarchical clustering analysis were made based on the combined mean values of EOCs using the R-software version 4.2.2 packages. A total of 21 EOCs were detected from the essential oil of 64 EBCGs using GC-MS, out of which ρ-cymene, thymoquinone, α-thujene, carvacrol, trans-4-methoxythujane, longifolene, terpinen-4-ol, β-pinene, α-pinene, and d-limonene dominated the essential oils. Among these, ρ-cymene, thymoquinone, α-thujene, trans-4-methoxythujane, and carvacrol were the most abundant constituents in all genotypes, while the rest varied among the genotypes. It is predicted that the major EOCs will be improved by 25.33%–152.14% over improved varieties by selecting the top 5% of landraces. The abundant EOC thymoquinone had a significant and positive correlation with carvacrol and a strong and significant negative correlation with α-thujene, α-pinene, β-pinene, ρ-cymene, and d-limonene. Based on the major EOCs, cluster analysis grouped the 64 genotypes into two different chemotypes. Cluster-I: Chemotype A is characterized by a high content of thymoquinone. Cluster-II: Chemotype B is characterized by a high content of ρ-cymene. The presence of the most abundant volatile constituents in genotypes 242835, 9068, and 014_ATH means they are essential for the pharmaceutical and food industries. This study disclosed the existence of a significant diversity of EOCs among the Ethiopian N. sativa genotypes, which can be exploited for future improvement programs.
... Te oil also treats respiratory conditions such as asthma, emphysema, and bronchitis [4]. Several fndings reported that black cumin has diferent pharmacological activities such as antioxidant [5], antidiabetic [6], antifungal [7][8][9][10][11], antiviral [12][13][14][15], antiparasitic [16][17][18][19], anticancer [20], and antibacterial [21]. ...
... It is used Te oil also treats respiratory conditions such as asthma, emphysema, and bronchitis [4]. Several fndings reported that black cumin has diferent pharmacological activities such as antioxidant [5], antidiabetic [6], antifungal [7][8][9][10][11], antiviral [12][13][14][15], antiparasitic [16][17][18][19], anticancer [20], and antibacterial [21]. ...
Black cumin (Nigella sativa L.) seeds essential oil compositions (EOCs) have been used for their medicinal and aromatic values across the world since ancient times. Studies have revealed the presence of variability among black cumin genotypes in EOCs. In Ethiopia, few studies have been conducted to explore the variability of black cumin genotypes by using EOCs. This study investigated the variability of Ethiopian black cumin genotypes (EBCGs) by EOCs. Seeds of 64 N. sativa genotypes were used for this experiment. Composite samples of 100 g of seeds were collected and roughly ground from each genotype. The extraction was made by hydrodistillation using a Clevenger-type apparatus for 3 h, and the essential oil was collected by measuring the amount using a measuring pipette. The essential oil samples were stored in a refrigerator at 4°C until gas chromatography–mass spectrometry (GC-MS) analysis. Descriptive statistics was used to estimate the variations among populations’ combined mean values of EOCs using the SAS version 9.4 software package. The correlation and hierarchical clustering analysis were made based on the combined mean values of EOCs using the R-software version 4.2.2 packages. A total of 21 EOCs were detected from the essential oil of 64 EBCGs using GC-MS, out of which ρ-cymene, thymoquinone, α-thujene, carvacrol, trans-4-methoxythujane, longifolene, terpinen-4-ol, β-pinene, α-pinene, and d-limonene dominated the essential oils. Among these, ρ-cymene, thymoquinone, α-thujene, trans-4-methoxythujane, and carvacrol were the most abundant constituents in all genotypes, while the rest varied among the genotypes. It is predicted that the major EOCs will be improved by 25.33%–152.14% over improved varieties by selecting the top 5% of landraces. The abundant EOC thymoquinone had a significant and positive correlation with carvacrol and a strong and significant negative correlation with α-thujene, α-pinene, β-pinene, ρ-cymene, and d-limonene. Based on the major EOCs, cluster analysis grouped the 64 genotypes into two different chemotypes. Cluster-I: Chemotype A is characterized by a high content of thymoquinone. Cluster-II: Chemotype B is characterized by a high content of ρ-cymene. The presence of the most abundant volatile constituents in genotypes 242835, 9068, and 014_ATH means they are essential for the pharmaceutical and food industries. This study disclosed the existence of a significant diversity of EOCs among the Ethiopian N. sativa genotypes, which can be exploited for future improvement programs.
... TQ, THQ, and thymol exhibit potent antifungal action against several pathogenic fungi, molds, and yeasts [87][88][89]. Rogozhin et al. [88] isolated two novel defensins from black cumin, namely Ns-D1 and Ns-D2, which displayed significant antifungal activity against a range of phytopathogenic fungi. Black cumin defensins (Ns-D1 and Ns-D2) showed potent antifungal activity with IC50 values below 10 μg/mL for most tested fungi. ...
In this review, a comprehensive and systematic evaluation of the phytochemical constituents, traditional medicinal applications, current pharmacological research, toxicity, and nanobiotechnology of black cumin has been undertaken. An exhaustive database retrieval was conducted to collect scientific information about Nigella sativa L. from 1956 to 2025 using PubMed, Scopus, ISI Web of Science, SciFinder, and CABI. Search was carried out using the keywords “Nigella sativa,” “Nigella oil,” “Ethnobotany,” “Phytochemistry,” “Pharmacological activity,” “Toxicity,” and “Nanotechnology.” Several important phytochemicals are found in the seeds of N. sativa L., and many of which seem to have a good impact on human health and are put to important use in the Ayurvedic, Unani, and Siddha systems of medicine. Among the active compounds, thymoquinone is the most important, forming about 30%–48% of the oil fraction. Besides thymoquinone, a wide range of phytochemicals such as thymohydroquinone, dithymoquinone, p‐cymene, sabinene, carvacrol, 4‐terpineol, kaempferol (glucoside) t‐anethol, longifolene (sesquiterpene), α‐pinene, α‐hederin (pentacyclic triterpene), and thymol have also been reported. Current research has provided scientific evidence for the traditional uses of black cumin, especially antioxidant, anti‐inflammatory, antibacterial, antifungal, antiviral, anticancer, antidiabetic, neuroprotective, gastroprotective, and antiarthritic effects. The review provides an in‐depth analysis of the phytochemistry, traditional uses as well as potential pharmacological properties of N. sativa L. Since the plant is being extensively investigated for its medicinal properties, this review provides valuable up‐to‐date information on the current research status and will act as a reference for future research and applications of this important medicinal plant.
... Additionally, it was just as effective when used against Candida tropicalis, Candida albicans, and Candida krusei. According to the findings of Taha et al. (2010), the active components of black-cumin, such as TQ, and thymol, were particularly efficient against a broad range of clinically isolated fungal strains. These clinically isolated fungal strains included Apple Academic Press Author Copy dermatophytes, molds, and yeasts. ...
Seeds from the plant Nigella sativa have been used for a very long time in
a number of different cultures to cure a broad variety of medical ailments
in both people and animals. Numerous studies have demonstrated that
the black cumin seed and its primary bioactive principal, thymoquinone,
are extremely effective in the treatment of a wider variety of diseases.
Because of the fact that it has such a high concentration of antioxidants,
there has been a recent uptick in interest in the possibility of using this
important seed as a dietary supplement without experiencing many
adverse effects. In addition to this, it enhances the efficacy of many
traditional chemotherapeutic treatments, making it possible to decrease
the dose of other medicines that are being taken at the same time while
still achieving the desired level of efficiency with very little to no side
effects. It is believed that the seeds of the N. sativa plant possess a wide
variety of therapeutic and biological properties. In order to better understand
the functional food and nutraceutical potential of black cumin, the present chapter focuses on the profile of high-valued principles mixed
with conventional medicinal and biochemical principles of the seed and
its oil.
... Most Ethiopian people use it as house holdings' spice preparation. Several studies, also confirm the application of black cumin seed for medicinal purposes for internal and external problems treatment (Bafghi et al. 2011;Barakat et al. 2013;Daryabeygi-Khotbehsara et al. 2017;Mahmoudvand et al. 2014;Marongiu et al. 2013;Okeol et al. 2011;Onifade et al. 2015;Schneider-Stock et al. 2014;Shokri 2016;Taha et al. 2010;Vasant et al. 2012). Besides its medicinal importance, black cumin seed oil is also used for the production of soap, perfumes and lotions; food flavorings, food preservation, nutraceuticals and cosmeceuticals (Atta 2003;Takrun et al. 1998). ...
as well as seed yield and yield-related qualitative traits by 4-41% over improved varieties by the selection of the top 5% landraces. Thus, through selection, it would also be possible to shorten the flowering and maturity periods of the genotypes. High broad sense heritability values coupled with high to moderate genetic advance as a percentage of mean values were shown by the number of capsules per plant and plant height which indicates possibilities for improvement of these traits through selection. Plant height, number of primary branches per plant, number of seeds per capsule and thousand seeds weight had a positive and significant phenotypic and genotypic association with seed yield per hectare. Plant height and seed yield per plant had a positive direct effect on seed yield per hectare phenotypically and genotypically. This would be a direct selection criterion for further improvement of the genotypes. The principal component analysis of 12 quantitative traits exhibited 81.5% of the total variance captured by the first four principal components (PCs). Days to 50% flowering, days to full blooming, days to maturity, number of seeds per plant, and seed yield per plant were the main contributor traits for the variation in the first and second PCs. The genotypes were grouped into three different clusters (C-I = 35.93%, C-II = 9.38%, and C-III = 54.69%) based on 12 quantitative traits with significant inter-cluster distances. This clearly showed that there was sufficient diversity among the genotypes which can be exploited for the future black cumin improvement program. Abstract This study was conducted to investigate the variability of Ethiopian black cumin genotypes by using morpho-agronomic traits. Sixty-four genotypes were tested at Debre Zeit and Kulumsa Agricultural Research center in 2021 using an 8 × 8 simple lattice design with two replications. Analysis of variance revealed significant (p ≤ 0.001 or p ≤ 0.01) differences among the genotypes for all traits studied, except the number of primary branches per plant. The effect of location was significant (p ≤ 0.001 or p ≤ 0.05) for all traits except the number of primary branches per plant. It is expected to improve all phenological traits Supplementary Information The online version contains supplementary material available at https:// doi.
Black cumin, or Nigella sativa, is a medicinal plant that is extensively recognised and used on a global scale. This study examines the historical use of black seed in both traditional and modern medicine, as well as its antibacterial, antifungal, antiviral, and anti-parasitic properties. Methods: Data were collected by employing a variety of reputable scientific search engines, such as Google Scholar, ScienceDirect, Taylor & Francis, and Wiley Library…etc. The data was processed and analysed by the author's team to reach the following conclusion: We strongly encourage medical personnel to investigate the integrated application of black cumin as a therapeutic agent alongside contemporary compounds, given the comprehensive antimicrobial efficacy of black seed against pathogenic bacteria, viruses, fungi, and parasites.
Black cumin (Nigella sativa L.) (family Ranunculaceae) is a largely utilized therapeutic herb worldwide. This comprehensive review discusses the pharmacological benefits of black cumin seed oil, focusing on its bioactive component thymoquinone (TQ). The review is structured as follows: First, we examine the antimicrobial properties of black cumin oil, followed by an analysis of its antioxidant capabilities. Finally, we explore its therapeutic potential, particularly in neurodegenerative diseases and COVID-19. Phytochemicals from N. sativa have exhibited potential for developing novel preventive and therapeutic strategies against jaundice, gastrointestinal disorders, skin diseases, anorexia, conjunctivitis, dyspepsia, intrinsic hemorrhage, amenorrhea, paralysis, anorexia, rheumatism, diabetes, hypertension, fever, influenza, eczema, asthma, cough, bronchitis, and headache. The broader spectrum of application for N. sativa and its essential bioactives have certainly enhanced the commercial value of this seed oil. TQ, a major constituent of black cumin seed oil, has numerous beneficial properties. Researchers have extensively studied black cumin seed oil and its major component, TQ. These studies have revealed a wide range of pharmacological properties, including anticancer, immunomodulatory, analgesic, antimicrobial, antidiabetic, and anti-inflammatory effects. Additionally, TQ has shown neuroprotective, spasmolytic, bronchodilatory, hepatoprotective, renoprotective, gastroprotective, and antioxidant activities.
Background:
Nigella sativa L. has been widely used in the Unani, Ayurveda, Chinese, and Arabic medicine systems and has a long history of medicinal and folk uses. Several phytoconstituents of the plant are reported to have excellent therapeutic properties. In-vitro and in-vivo studies have revealed that seed oil and thymoquinone have excellent inhibitory efficacy on a wide range of both pathogenic and non-pathogenic fungi.
Objective:
The present review aims to undertake a comprehensive and systematic evaluation of the antifungal effects of different phytochemical constituents of black cumin.
Method:
An exhaustive database retrieval was conducted on PubMed, Scopus, ISI Web of Science, SciFinder, Google Scholar, and CABI to collect scientific information about the antifungal activity of N. sativa L. with 1990 to 2023 as a reference range using ‘Nigella sativa,’ ‘Nigella oil,’ ‘antifungal uses,’ ‘dermatophytic fungi,’ ‘candidiasis,’ ‘anti-aflatoxin,’ ‘anti-biofilm’ and ‘biological activity’ as the keywords.
Results:
Black cumin seeds, as well as the extract of aerial parts, were found to exhibit strong antifungal activity against a wide range of fungi. Among the active compounds, thymoquinone exhibited the most potent antifungal effect. Several recent studies proved that black cumin inhibits biofilm formation and growth.
Conclusion:
The review provides an in-depth analysis of the antifungal activity of black cumin. This work emphasizes the need to expand studies on this plant to exploit its antifungal properties for biomedical applications.
The aerial parts of Ocimum gratissimum L. (Lamiaceae) harvested in Togo was steam-distilled and investigated for essential oil composition (GC and GC/MS) and in vitro antifungal activities. Thymol (31.79 %), p-cymene (15.57 %) and γ-terpinene (12.34 %) and were the major components of the oil. Other notable components identified in this oil were myrcene (6.94 %) and α-thujene (6.11 %).The in vitro antifungal activity was recorded with the minimum inhibitory concentrations (MICs) ranging from 80 to 150 µl.l-1 , 150 to 500 µl.l-1 and from 100 to 150 µl.l-1 respectively on dermatophytes, imperfect filamentous fungi and pathogenic yeasts. Likewise, on tested fungi the minimum fungicidal concentration (MFC) varied from 300 µl.l-1 to 500 µl.l-1 , 500 to 700 µl.l-1 and from 250 to 300 µl.l-1 , respectively on dermatophytes, imperfect filamentous fungi and pathogenic yeasts.
Thymoquinone (TQ) is the major active component of the volatile oil of Nigella sativa seeds. The effects of TQ on carbon tetrachloride (CC14)‐induced hepatotoxicity was investigated in male Swiss albino mice. Carbon tetrachloride (20 μl/Kg, i.p.) injected into mice, induced damage to liver cells and was followed by the increase in serum alanine aminotransferase (ALT) activity after 24 h. Oral administration of TQ in a single dose (100 mg/Kg) resulted in significant (p<0.001) protection against the hepatotoxic effects of CCl4.
TQ was tested as a substrate for mice hepatic DT‐diaphorase in the presence of NADH. TQ appears to undergo reduction to dihydrothymoquinone (DHTQ). Reduction rates as a function of protein (liver homogenate) and substrate (TQ) concentrations are reported. An apparent Km of 0.1 mM and an apparent Vmax of 74 μmol/min/g liver were measured.
TQ and DHTQ inhibited the in vitro non‐enzymatic lipid peroxidation in liver homogenate (induced by Fe3+‐ascorbate) in a dose dependent manner. In this in vitro model DHTQ was more potent in comparison with TQ and butylated hydroxytoluene (BHT). The IC50 for DHTQ, TQ and BHT were found to be 0.34, 0.87 and 0.58 μM respectively. The data suggest that the in vivo protective action of TQ against CCl4‐induced hepatotoxicity may be mediated through the combined antioxidant properties of TQ and its metabolite DHTQ.
Tannins are one of the most broadly distributed types of plant secondary compounds, and have been the focal point for many studies of plant/herbivore interactions. Tannins interact strongly with proteins, so that the fate and effects of ingested tannins are in part dependent on the mode of interaction of the tannin with dietary and endogenous proteins in an herbivore's gut. We investigated the factors affecting the precipitation of proteins by phlorotannins from three species of marine brown algae:Carpophyllum maschalocarpum, Ecklonia radiata, andLobophora variegata. Phlorotannins were precipitated by proteins in a pH-dependent and concentration-dependent fashion. Precipitation also varied as a function of the presence of reducing agent, the type of phlorotannin or protein used, and the presence of organic solvents such as hydrogen bond inhibitors. Of particular significance was the ability of some phlorotannins to oxidize and form covalent bonds with some proteins. In contrast, under similar experimental conditions three types of terrestrial tannins (procyanidins, profisetinidins, and gallotannins) apparently did not form covalent complexes with proteins. Our results suggest several ways in which the biological activity of phlorotannins may vary as a function of the properties of the gut environment of marine herbivores. Moreover, we identify specific structural characteristics of phlorotannins which affect their tendency to oxidize, and thus, their potential effects on marine herbivores.
The seeds of Nigella sativa are used commonly in the Middle East as a traditional medicine to treat a variety of health conditions. This paper examines the levels of selenium, dl-α-tocopherol, dl-γ-tocopherol, all-trans-retinol, thymoquinone and thymol in different brands of N. sativa seeds purchased from local markets in Riyadh, Saudi Arabia. Selenium was determined by the inductively coupled plasma spectrometry coupled with the hydride system. dl-α-tocopherol, dl-γ-tocopherol, all-trans-retinol, thymoquinone and thymol were measured by high-performance liquid chromatography. The average mean concentrations (mg/kg fresh weight) of selenium, dl-α-tocopherol, dl-γ-tocopherol, all-trans-retinol, thymoquinone and thymol in all tested seeds were 0.17±0.10, 9.02±4.84, 5.42±3.96, 0.27±0.27, 2224.49±1629.50 and 169.35±100.12, respectively. The concentrations of these analytes were significantly affected by the country of origin of the N. sativa. It is concluded that N. sativa provides an important source of antioxidants.
Problem statement: The developing microbial resistance to the existing anti-microbial agents has become a real challenge and a serious problem facing patients suffering from skin infections. Seeds of Nigella sativa have been used for a long time in folk medicine for the treatment of such infections. Production of new potent agents is urgently needed, especially for hospitals and health centers. Therefore, the anti-microbial effect of aqueous, diethyl ether, chloroform and petroleum ether extracts of the seeds against four standard microbial strains and seven clinical isolates from patients with skin wound infections were investigated. Approach: The in vitro anti-microbial effect of the extracts at a concentration of 20% on standard strains and clinical isolates was assessed and compared with standard drugs, chloramphenicol and amphotericin B using agar well diffusion assay. The in vivo anti-bacterial effect of petroleum ether extract was studied in male BALB/c mice infected subcutaneously with S. aureus (ATCC 25923) or a clinical isolate (0.1 mL from 10<SUP>9 </SUP>colony forming units mL<SUP>-1</SUP> suspension) and immediately treated at the infected site by subcutaneous injection of 0.1 mL of pure extract (fixed oil) or chloramphenicol or normal saline. Counts of viable bacteria present in the skin area corresponding to the infected site were determined, after 24 and 48 h of infection and treatment. Results: The aqueous extract did not show any inhibitory effect against all the tested microorganisms. The diethyl ether and chloroform extracts indicated significant inhibitory effect only against Gram-positive bacteria. However, petroleum ether extract was proved to be the most powerful one against these bacteria and also against other clinical isolates like one Gram-negative bacterium ( Klebsiella pneumonia ) and the yeast ( Candida albicans ). Moreover, the extract revealed a superior effect over the standard drug, chloramphenicol, on the clearance of subcutaneous staphylococcal infection in mice when injected at the site of infection. Counts of viable bacteria were decreased at highly significant level in mice infected with S. aureus (ATCC 25923) or a clinical isolate. Conclusion/Recommendations: The results of this study revealed clear potentiality of N. sativa fixed oil as a source for anti-microbial drugs and support its use in folk medicine for the treatment of microbial skin infections.
Several effects of thymol, a plant-derived antimicrobial agent, on Porphyromonas gingivalis, Selenomonas artemidis and Streptococcus sobrinus were examined. The extremely rapid efflux of intracellular constituents evoked by thymol is consistent with its postulated membranotropic effects. Correlations between leakage-inducing concentrations of thymol and minimal inhibitory concentrations and minimal bactericidal concentrations suggest that membrane perforation is a principal mode of action of this substance. The thymol-induced decline in intracellular ATP in S. sobrinus appears to be entirely attributable to leakage, whereas in P. gingivalis thymol may also inhibit ATP-generating pathways. Relative changes in the transmembrane potential of resting cells of S. sobrinus pulsed with glucose are as sensitive to thymol as is leakage from this organism. The effects of thymol on transmembrane potential are probably secondary to those arising from leakage of intracellular substances.
The biological effects of supplementing broad bean (Vicia faba) or corn (Zea maize) meal protein with black cumin (Nigella sativa) cake protein as well as their amino acid composition were investigated. The percentage of total protein content of Nigella cake was 22.7%. Lysine is existent in abundant amounts in faba meal protein, while leucine is the most abundant in corn meal protein (chemical score = 156) and valine is higher in Nagella cake protein. compared with rats fed sole corn or faba meal protein, substitution of 25% of corn or faba meal protein with Nigella cake protein in the diet remarkably raised the growth rate of rats and resulted in significant higher levels of rat total serum lipids and triglycerides. Also, the supplemented diet caused significant increases in serum total protein and its two fractions albumin and globulin and insignificantly increase the activity of serum phosphatases and transaminases within normal ranges. The supplementation did not have any adverse nutritional effects in the levels of lipid fractions in the serum.
An HPLC method for quantifying the putative pharmacologically active constituents: thymoquinone (TQ), dithymoquinone (DTQ), thymohydroquinone (THQ), and thymol (THY), in the oil of Nigella sativa seed is described. Extraction of the constituents from the oil was carried out using C18 PrepSep mini columns followed by quantification of the recovered constituents by HPLC on a reversed-phase muBondapak C18 analytical column, using an isocratic mobile phase of water:methanol:2-propanol (50:45:5% v/v) at a flow rate of 2 ml min(-1). UV detection was at 254 nm for TQ, DTQ, and THY, and at 294 nm for THQ. The above four compounds were separated with good resolution, reproducibility, and sensitivity under these conditions. This analytical method was used to quantify the above four constituents in a commercial sample of N. sativa seed oil, and provides a good quality control methodology for the pharmacologically active components in this widely used natural remedy.