The efficacy of Nigella sativa L. oil on serum biomarkers of inflammation and oxidative stress and quality of life in patients with knee osteoarthritis: A parallel triple-arm double-blind randomized controlled trial

The aim of this double-blind clinical trial was to investigate the effects of Nigella sativa oil on serum inflammatory and oxidative stress biomarkers and quality of life in patients with knee osteoarthritis (OA). Forty-five patients who met the eligibility criteria were randomly divided into three groups with a ratio of 1:1:1. The first group received 2.5 mL oral N. sativa oil twice/day plus placebo topical oil, the second group received 2.5 mL topical N. sativa oil three times/day plus placebo oral oil, and the third group received oral and topical oil placebos. There were no intergroup differences in baseline characteristics. After 6 weeks of supplementation, oral N. sativa caused a significant improvement in the serum levels of hs-CRP (p = .003), MDA (p = .003), and TAC (p = .001). Oral N. sativa oil compared to placebo (aMD (95% CI): -0.81 (-1.45 to -0.19); p = .012) and topical N. sativa oil [aMD (95% CI): -0.76 (-1.38 to -0.15); p = .016] significantly reduced hs-CRP serum levels. Significant improvements were observed in the general, physical, and mental health subscales in the oral and topical N. sativa oil compared to the placebo group (p < .05). The six-week oral N. sativa oil supplementation was effective in improving inflammatory biomarkers in knee OA. Both oral and topical N. sativa oil increased the quality of life.

Nigella sativa L. seed extracts promote wound healing progress by activating VEGF and PDGF signaling pathways: An in vitro and in silico study

Background: A significant area of clinical research is the development of natural wound healing products and the management of chronic wounds. Healing wounds with medicinal plants has been a practice of ancient civilizations for centuries. Nigella sativa L (N. sativa) is a medicinal plant that has several pharmacological properties. Methods: The present study evaluated the wound healing properties of Nigella sativa L. ( N. sativa) seed extracts using normal cell lines such as normal human dermal fibroblasts (NHDFs) and human umbilical vein endothelial cells (HUVECs). The expression levels of vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) were analyzed through western blot analysis. Furthermore, computational analyses were carried out to screen the potential bioactive compounds for wound healing applications. Results: The results of the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay revealed that, all the tested solvent extracts of N. sativa seeds (including ethanol, ethyl acetate, chloroform, and petroleum ether) did not exert any cytotoxic effects at the tested concentrations. Furthermore, the western blot analysis showed elevated levels of VEGF and PDGF upon treatment with N. sativa seed extracts. Gas chromatography-mass spectrometry (GC-MS) analysis of N. sativa extracts identified 268 phytocompounds. Molecular docking studies revealed that three phytocompounds of N. sativa extracts, including tricyclo[20.8.0.0(7,16)]triacontane, 1(22),7(16)-diepoxy-, adaphostin and obeticholic acid had strong binding affinity with wound healing-related target proteins, showing docking scores ranging from -5.5 to -10.9 Kcal/mol. These compounds had acceptable Absorption, Distribution, Metabolism, and Excretion (ADME) properties. Conclusions: Based on these results, N. sativa seed extracts might possess potential wound healing properties owing to the presence of a wide range of bioactive components.

Effect of Nigella sativa L. seed oil on urinary incontinence and quality of life in menopausal women: A triple-blind randomized controlled trial

Increased urinary incontinence is one of the most common changes during menopause. This study aimed to investigate the effect of Nigella sativa L. seed oil on urinary incontinence and quality of life (QoL) (primary outcomes) and sexual function (secondary outcome) in menopausal women. In this triple-blind randomized controlled trial, 60 women in Tabriz-Iran were equally allocated into two treatment and control groups using block randomization. The women applied 2-3 drops of Nigella sativa L. seed oil or placebo on their stomachs below the novel twice a day for 8 weeks. The data collection instruments were completed at baseline and just after the intervention. After intervention, the mean rank score of mixed urinary incontinence was significantly lower (p = .04) and the mean score of the incontinence-QoL was significantly higher (mean difference 12.63, 95% CI 2.33 to 22.93; p = .017) in the treatment group than the control group. However, there were no significant differences in stress incontinence, urge incontinence, sexual function, and menopause-specific QoL of women between the groups (p > .05). The results indicated the positive effect of the Nigella sativa L. seed oil on mixed incontinence and incontinence-QoL; nevertheless, to make a certain conclusion, further studies are required.

Biological Properties, Phenolic Profile, and Botanical Aspect of Nigella sativa L. and Nigella damascena L. Seeds: A Comparative Study

The use of Nigella seeds in the food, pharmaceutical, and cosmetic fields is common, since the iniquity and the virtues of these plants are directly related to their characteristic phytochemical composition. This investigation focused on the comparative study of the botanical aspect, phenolic profile, and in vitro and in vivo biological activities of Nigella sativa L. (NS) and Nigella damascena L. (ND) seeds. The macro- and micro-morphological properties of these seeds were studied, and the key dissimilarities between them were clearly illustrated. The phytochemical contents and phenolic profiles were determined, and the in vitro antioxidant activity was assessed using four methods. The in vivo antioxidant and biochemical parameters of the blood of supplemented mice were determined. The results of the macro- and micro-structure analysis revealed differences between the two plants. Here, ND is characterized by higher phytochemical contents and the best antioxidant activities. The HPLC analysis indicated the presence of nine compounds, namely seven phenolic acids, particularly hydroxybenzoic and caffeic acids, and two flavonoids. The administration of ND extract to mice for 21 days at a concentration of 500 mg/kg allowed a substantial amelioration of plasma antioxidant properties. In addition, the extracts ameliorate blood parameters (cholesterol, triglycerides, glycemia, and urea). Furthermore, the antimicrobial activity of extracts demonstrated their effects on Staphylococcus and Aspergillus. Nigella seeds, in particular ND, expressed considerable in vitro antioxidant properties and demonstrated significant amelioration of mice blood properties. Consequently, these species can serve as a valuable source of compounds with various applications.

Application of biorefinery by-product of Nigella sativa L. herb for green treatment of synthetic dye impurity in aquatic environment: a circular economy based approach to water purification

In this work, the performance of residual biomass of Nigella sativa L. plant from the process of bio-oil production toward the green removal of synthetic dye pollution from aquatic medium was systematically studied for the first time based on the circular economy strategy. The characterization of material was performed using Electron Microscope of Scanning and Infrared Spectrometer of Fourier Transform. The main process variables like pH, biosorbent amount, synthetic dye loading, and contact duration were optimized by the batch biosorption experiments to achieve the maximum remediation yield. The analyses of kinetics, equilibrium, and thermodynamics were conducted to understand the possible mechanism of purification. The experimental dynamics and equilibrium data were in better agreement with the pseudo-second-order and Langmuir models. For the targeted model synthetic dye compound (C. I. Basic Red 46), the biosorption capacity was obtained as 136.2 mg g^-1 at the optimized conditions of pH of 8, biosorbent amount of 10 mg (100 mg L^-1), synthetic dye loading of 30 mg L^-1, and duration of 360 min. The treatment process was favorable, spontaneous, and physical. The characterization operation showed that the dye molecules were restrained on the rough surface of biosorbent. This study reveals that the reuse of herbal oil refinery residue as a biosorbent can present an economic, efficient, and eco-friendly option for the remediation of synthetic dye pollution in aqueous medium.

Determination of Some Chemical Elements of Common Spices Used by Algerians and Possible Health Risk Assessment

Spices in general owned a very important reputation in the herbal plantae Kingdom; they have been used for food flavoring, preservation, aroma, and coloring for more than 2000 years. Moreover, spices are classified as all natural, and for this reason, they attracted a large scale of consumers worldwide; however, since most of spices are consumed in their natural form (without grounded them), it is necessary to monitor their consumed quantities. Hence, the aim of this work was to quantify major and trace elements contained in some Algerian kitchen frequently used spices (Piper nigrum L., Nigella sativa L., and Pimpinella anisum L.). Spice materials were washed well then pass through an instrumental neutron activation analysis (INAA). Results revealed the existence of twenty-six elements among them: K, Ca, Fe, and Na which showed significant concentrations, consecutively, while Ce, Eu, Lu, Sm, and Tb were presented at low concentrations. Furthermore, these spices consumption assessment results were found to be well below the tolerance limits compared with the recommended values (RDA) suggested by the FAO association.

Nigella sativa L. and COVID-19: A Glance at The Anti-COVID-19 Chemical Constituents, Clinical Trials, Inventions, and Patent Literature

COVID-19 has had an impact on human quality of life and economics. Scientists have been identifying remedies for its prevention and treatment from all possible sources, including plants. Nigella sativa L. (NS) is an important medicinal plant of Islamic value. This review highlights the anti-COVID-19 potential, clinical trials, inventions, and patent literature related to NS and its major chemical constituents, like thymoquinone. The literature was collected from different databases, including Pubmed, Espacenet, and Patentscope. The literature supports the efficacy of NS, NS oil (NSO), and its chemical constituents against COVID-19. The clinical data imply that NS and NSO can prevent and treat COVID-19 patients with a faster recovery rate. Several inventions comprising NS and NSO have been claimed in patent applications to prevent/treat COVID-19. The patent literature cites NS as an immunomodulator, antioxidant, anti-inflammatory, a source of anti-SARS-CoV-2 compounds, and a plant having protective effects on the lungs. The available facts indicate that NS, NSO, and its various compositions have all the attributes to be used as a promising remedy to prevent, manage, and treat COVID-19 among high-risk people as well as for the therapy of COVID-19 patients of all age groups as a monotherapy or a combination therapy. Many compositions of NS in combination with countless medicinal herbs and medicines are still unexplored. Accordingly, the authors foresee a bright scope in developing NS-based anti-COVID-19 composition for clinical use in the future.

A novel biowaste-based biosorbent material for effective purification of methylene blue from water environment

The biowaste left over from the fixed oil biorefinery process of Nigella sativa L. plant was used as a new biosorbent for the biosorption of synthetic dye of methylene blue from water environment in this study. The main variables of biosorption operation such as methylene blue concentration, time, pH, and biosorbent amount were optimized by the batch-type experiments. The characterization, kinetics, equilibrium, and thermodynamics works were conducted to show the nature of methylene blue biosorption. The studies of Fourier transform infrared spectroscopy and Scanning electron microscopy indicated that the biosorbent possessed an inhomogeneous surface morphology including many cavities and protuberances, and a rich functional group profile. The optimum values of operating variables studied for the biosorption of methylene blue were determined as methylene blue concentration of 15 mg L^-1, time of 360 min, pH of 8, and biosorbent amount of 10 mg. The experimental data of methylene blue biosorption followed the kinetics and isotherm models of pseudo-second-order (R²: 0.98, AdjR²: 0.98, and RMSE: 8.97) and Dubinin-Radushkevich (R²: 0.99, AdjR²: 0.98, and RMSE: 6.84), respectively, based on the statistical tests of coefficient of determination (R²), adjusted coefficient of determination (AdjR²), and root mean squared error (RMSE). The biosorption of methylene blue was a physical, spontaneous, and energetically favorable process (E_DR: 3.48 kJ mol^-1 and ΔG°: (-14.51) - (-10.02) kJ mol^-1). This residual biological material from the fixed oil biorefinery process exhibited higher biosorption performance (187.46 mg g^-1) than own unrefined (virgin) form and its modified, activated, and composite forms and many other sorbents reported in the literature. Hereby, the current work showed that this novel biowaste-based material could be used as an environmentally and economically promising biosorbent to effectively purify methylene blue from aquatic environment.

Deodorant Activity of Black Cumin Seed Essential Oil against Garlic Organosulfur Compound

The deodorant activity of black cumin (Nigella sativa L.) seed, a spice used to flavor curry and vegetable foods in Southwest Asia, against garlic (Allium sativum L.) organosulfur compounds related to human malodor was evaluated. Black cumin seed essential oil showed remarkable deodorant activity against garlic essential oil. The mode of action of this deodorant activity was presumed to be that black cumin seed essential oil covalently reacted with the organosulfur compounds in garlic. Therefore, thymoquinone, which is a major constituent in black cumin seed essential oil, and allyl mercaptan, which is one of the organosulfur compounds produced by cutting garlic, were reacted in vitro, and the products were purified and elucidated using spectroscopic data. As a result, these substances were identified as different allyl mercaptan adducts to dihydrothymoquinone. This chemical reaction was presumed to play a key role in the deodorant activity of black cumin seed essential oil.

Effects of Nigella sativa, Camellia sinensis, and Allium sativum as Food Additives on Metabolic Disorders, a Literature Review

Objective: Metabolic disorders (MD) can disturb intracellular metabolic processes. A metabolic disorder can be resulted from enzyme deficits or disturbances in function of various organs including the liver, kidneys, pancreas, cardiovascular system, and endocrine system. Some herbs were used traditionally for spices, food additives, dietary, and medicinal purposes. Medicinal plants possess biological active compounds that enhance human health. We aimed to provide evidence about therapeutic effects of some medicinal herbs on MD.

Data Sources: PubMed, Scopus, and Google Scholar were explored for publications linked to MD until February 2021. The most literature reports that were published in the last 10 years were used. All types of studies such as animal studies, clinical trials, and in vitro studies were included. The keywords included “Metabolic disorders,” “Nigella sativa L.,” “Thymoquinone,” “White tea”OR “Camellia sinensis L.” “catechin,” and “Allium sativum L.” OR “garlic” were searched.

Results: Based on the results of scientific studies, the considered medicinal plants and their active components in this review have been able to exert the beneficial therapeutic effects on obesity, diabetes mellitus and non-alcoholic fatty liver disease.

Conclusions: These effects are obvious by inhibition of lipid peroxidation, suppression of inflammatory reactions, adjustment of lipid profile, reduction of adipogenesis and regulation of blood glucose level.

Linking the Phytochemicals and the α-Glucosidase and α-Amylase Enzyme Inhibitory Effects of Nigella sativa Seed Extracts

Nigella sativa L. (Ranunculaceae), commonly referred to as black seeds or black cumin, is used in popular medicine (herbal) all over the world for the treatment and prevention of several diseases, including diabetes. This study aims to investigate the inhibitory effect of N. sativa extracts and fractions against the activities of intestinal α-glucosidase and pancreatic α-amylase in vitro, and to explain the inhibitory effect of these fractions against these enzymes by identifying their active compounds responsible for this effect and determine their modes of inhibition. To do so, N. sativa hexane and acetone extracts were prepared and analyzed by GC-MS and HPLC-DAD, respectively. The hexane extract was further fractioned into eight different fractions, while the acetone extract generated eleven fractions. The extracts as well as the resulting fractions were characterized and evaluated for their potential in vitro antidiabetic activity using intestinal α-glucosidase and pancreatic α-amylase inhibitory assays in vitro. Hexane extract and fractions were less active than acetone extract and fractions. In the case of intestinal α-glucosidase activity, the acetone fraction SA3 had a high inhibitory effect on intestinal α-glucosidase activity with 72.26 ± 1.42%, comparable to the effect of acarbose (70.90 ± 1.12%). For the pancreatic α-amylase enzymatic inhibitory assay, the acetone fractions showed an inhibitory capacity close to that for acarbose. In particular, the SA2 fraction had an inhibitory effect of 67.70 ± 0.58% and was rich in apigenin and gallic acid. From these fractions, apigenin, (-)-catechin, and gallic acid were further characterized for their inhibitory actions. IC₅₀ and inhibition mode were determined by analyzing enzyme kinetic parameters and by molecular modeling. Interestingly, (-)-catechin showed a possible synergistic effect with acarbose toward α-glucosidase enzyme inhibition, whereas apigenin showed an additive effect with acarbose toward α-amylase enzymatic inhibition. Furthermore, we studied the toxicity of N. sativa hexane and acetone extracts as well as that of acetone fractions. The result of acute toxicity evaluation demonstrated that N. sativa extracts were nontoxic up to a concentration of 10 g/kg, except for fraction SA3. Taken together, these results indicate that N. sativa extracts and/or derived compounds could constitute promising nutraceuticals for the prevention and treatment of type 2 diabetes mellitus.

Biogenic platinum nanoparticles using black cumin seed and their potential usage as antimicrobial and anticancer agent

Herein, the biogenic platinum nanoparticles (Pt NPs) were synthesized by using black cumin seed (Nigella sativa L.) extract as a reducing agent. The biogenic platinum nanoparticles synthesized by black cumin seed extract was characterized in detail by Transmission Electron Microscopy (TEM), UV-vis spectrophotometer, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS). According to TEM analysis, Pt nanoparticles have spherical shapes and sizes between 1-6 nm. Moreover, the biogenic Pt NPs was assessed for its cytotoxicity effect on MDA-MB-231 breast and HeLa cervical cancer lines and their antibacterial effect against selected strains of gram-positive and negative bacteria. The cytotoxicity and bacterial tests showed the effectiveness of biogenic Pt nanoparticles. Dose-dependent toxicity effects were shown in the MDA-MB-231 breast and HeLa cervical cancer lines (IC50: 36.86 μg/mL and 19.83 μg/mL, respectively). In addition, Pt NPs showed high zone diameters against gram-positive and gram-negative bacteria at concentrations of 100 and 500 μg/ml. These results contribute to the development of the pharmaceutical industry as a potential antibacterial and anticancer agent.

Nigella sativa L. for prevention of acute radiation dermatitis in breast cancer: A randomized, double-blind, placebo-controlled, clinical trial

OBJECTIVE

The present study aimed to evaluate the effectiveness of Nigella sativa L. (N. sativa) extract on preventing the incidence of acute radiation dermatitis (ARD) in breast cancer patients.

METHODS

Sixty-two breast cancer patients undergoing radiotherapy (RT) were randomly assigned to receiveN. sativa 5% gel or placebo. Patients were instructed to apply the medications twice daily during RT period. The severity of ARD, the incidence of moist desquamation, worst experienced pain, and skin-related quality of life (SRQOL) scores were assessed weekly during RT.

RESULTS

Patients who were treated with the N. sativa gel developed ARD significantly less frequently compared to those who used the placebo (p < 0.05 for all weeks except week 2, p = 0.36). The incidence time of grade 2 and 3 of Radiation Therapy Oncology Group and the European Organization for Research and Treatment of Cancer (RTOG/EORTC) toxicity was prolonged significantly with N. sativa gel as compared to placebo (35 vs. 29 days, p = 0.00 and 42 vs. 40 days, p = 0.01, respectively). Furthermore, the occurrence of moist desquamation was delayed in the N. sativa gel group compared with the placebo group (37 vs. 33 days, p = 0.01). The mean score of the worst pain that patients experienced in the placebo group was significantly higher than that of the N. sativa gel group at week 3 (2.5 ± 0.5 vs. 1.2 ± 0.3, p < 0.05). Nonetheless, the application of N. sativa gel had no significant effect on the SRQOL of patients at any week.

CONCLUSION

N. sativa extract significantly decreases the severity of ARD and delays the onset of moist desquamation in breast cancer patients.

Effect of Hydroethanolic Extract of Nigella sativa L. on Skin Wound Healing Process in Diabetic Male Rats

Background:

The aim of this study was to investigate the effect of hydroethanolic Nigella sativa L. extract on skin wound healing in diabetic male rats.

Methods

This experimental study was conducted on 49 male Wistar rats weighing 220–250 g divided into 7 groups of 7 each: control (nondiabetic untreated), sham (nondiabetic eucerin-treated), nondiabetic phenytoin (1%)-treated, diabetic untreated, and three diabetic groups treated independently with phenytoin 1%, hydroethanolic N. sativa extracts 20% or 40%. Diabetes was induced with 60 mg/kg streptozosin in one administration. After anesthesia, 2 × 1 cm² wounds were made on the rats’ backs and each group was administered with its own respective treatment until the wounds were healed completely. Tissue specimens were prepared for histological examinations. The areas of the wounds were measured every 3 days. The data were analyzed by ANOVA and Tukey's post-hoc test.

Results:

The mean duration of wound healing was 27 and 24 days for diabetic untreated and diabetic phenytoin-treated groups, respectively. Wounds were healed completely in nondiabetic untreated, sham, and nondiabetic phenytoin-treated groups on days 23, 24, and 21, respectively. The shortest duration of wound healing was seen in diabetic N. sativa extract (40%)-treated group (15 days) followed by diabetic N. sativa (20%)-treated group (18 days). These two groups were found to have the lowest mean wound area during the study with a significant difference from mean wound area in the controls (P < 0.05).

Conclusions:

N. sativa extract significantly promoted wound healing in diabetic rats in comparison with control groups. Although the beneficial mechanism of the promotion of wound healing was not specifically studied, it is believed that the anti-inflammatory and antimicrobial properties of N. sativa would contribute to this enhanced wound healing.

Nigella sativa L. and Its Bioactive Constituents as Hepatoprotectant: A Review

BACKGROUND

The pharmacological properties of Nigella sativa L. are well attributed to the presence of bioactive compounds, mainly, thymoquinone (TQ), thymol (THY) and α hederin and their antioxidant effects. TQ, THY and alpha-hederin (α-hederin) provide protection to liver from injury via different mechanisms including inhibition of iron-dependent lipid peroxidation, elevation in total thiol content and (GSH) level, radical scavenging, increasing the activity of quinone reductase, catalase, superoxide dismutase (SOD) and glutathione transferase (GST), inhibition of NF-κB activity and inhibition of both (COX) and (LOX) protects liver from injuries. Review and Conclusion: The main aim of this literature review is to reflect the relevant role of ROS in inducing hepatic diseases and also the preventive role of N. sativa L. in hepatic diseases. The present article is directed towards highlighting the beneficial contribution of researchers to explore the pharmacological actions with therapeutic potential of this precious natural herb and its bioactive compounds pertaining to the hepatoprotective effects. We systematically searched for research literature through well-framed review question and presented the data in the tabular forms for the convenience of the readers. Two hundred and forty-one papers were embodied in this review, oxidative effect and the reactive oxygen species (ROS) are known to be the major causes of many diseases such as hepatic cancer. Many drugs and chemicals have shown to incite oxidative damage by generation of ROS in the body. Therefore, this review intends to focus the role of ROS in liver diseases and the mechanisms through which N. sativa prevents hepatic diseases. The mechanisms by which N. sativa impede progression in chronic liver diseases should be used as a preventive medicine in patients with hepatic disorders.

Characterization of Aroma-Active Compounds in Seed Extract of Black Cumin (Nigella sativa L.) by Aroma Extract Dilution Analysis

Turkish Nigella sativa L. seed extracts were used to detect the aroma and key odorant compounds of the spice using gas chromatography-mass spectrometry-olfactometry (GC-MS-O). Volatile compounds were extracted by the purge and trap extraction (PTE) method. A total of 32 volatile compounds consisting of different chemical classes acids (13), alcohols (7), phenols (3), terpene (1), esters (2), ketones (2), aldehyde (1), lactone (1) and hydrocarbons (2) were determined. The amounts of volatile compounds were found to be 21,544 µg kg−1. The application of aroma extract dilution analysis (AEDA) revealed the presence of 13 odor-active compounds alcohols (2), carboxylic acids (4), phenols (2), terpene (1), ketone (1), hydrocarbon (1) and unknown compounds (2) in Nigella sativa L. extract. Flavor dilution (FD) factors of key odorants ranged between 4 and 1024, while odor activity values (OAV) were in the range of 1.0 to 170.8. Acetoin was the only aroma-active ketone detected in Nigella sativa L. seed extracts. It had the strongest aroma (FD = 1024) and provided a buttery odor. This compound represented the most abundant compound of overall aroma profile with a concentration of 9394 µg kg−1, followed by isobutanoic acid (FD = 512 with a concentration of 218 µg kg−1) and contributed a powerful aroma and a cheesy characteristic odor.

Some microbiological, physicochemical and ripening properties of Erzincan Tulum cheese produced with added black cumin (Nigella sativa L.)

The effects of black cumin (BC) at 0, 1 or 2% in Erzincan Tulum cheese (Tulum cheese) on its microbiological, chemical and proteolysis properties during ripening were investigated. The addition of BC caused an increase in the dry matter, protein, ash, total nitrogen (TN), water-soluble nitrogen (WSN) (% of TN) (ripening index), 5% phosphotungstic acid soluble nitrogen (PTA-SN) (% of TN), and 12% trichloroacetic acid soluble nitrogen (TCA-SN) (% of TN) concentrations compared to BC-free (control) cheese. Additionally, the addition of BC caused a decrease in coliforms, yeasts & moulds, fat-in-dry matter (FDM), pH, and acidity. The ripening period had an increasing effect on the dry matter, protein, FDM, salt, salt-in-dry matter (SDM), ash, acidity, TN, WSN, PTA-SN and TCA-SN concentrations. In addition, the ripening period had a decreasing effect on coliforms, yeasts & moulds, and pH. The count of Staphylococcus aureus in all Tulum cheeses made of raw sheep's milk was < 2 log cfu/g, ripening was faster and favourable Tulum cheese was produced. Therefore, 2 months after adding 2% BC to Tulum cheese that was produced using raw sheep milk immediately after milking as the original production method, it was found that Tulum cheese can be consumed more safely than coliform bacteria and yeasts & moulds.

Microwave-assisted extraction of Nigella sativa L. essential oil and evaluation of its antioxidant activity

It has been previously reported that the essential oil of Nigella sativa L. seeds and its major active component, thymoquinone (TQ), possess a broad variety of biological activities and therapeutic properties. In this work, microwave-assisted extraction (MAE) of the essential oil from Nigella sativa L. seeds and its antioxidant activity were studied. Response surface methodology based on central composite design was used to evaluate the effects of extraction time, irradiation power and moisture content on extraction yield and TQ content. Optimal parameters obtained by CCD and RSM were extraction time 30 min, irradiation power 450 W, and moisture content 50%. The extraction yield and TQ content of the essential oil were 0.33 and 20% under the optimum conditions, respectively. In contrast, extraction yield and TQ amount of oil obtained by hydrodistillation (HD) were 0.23 and 3.71%, respectively. The main constituents of the essential oil extracted by MAE and HD were p-cymene, TQ, α-thujene and longifolene, comprising more than 60% of total peak area. The antioxidant capacity of essential oils extracted by different methods were evaluated using 2,2-diphenyl-1-picrylhydrazyl and Ferric reducing antioxidant power assays, and compared with traditional antioxidants. The results showed that MAE method was a viable alternative to HD for the essential oil extraction from N. sativa seeds due to the excellent extraction efficiency, higher thymoquinone content, and stronger antioxidant activity.

Comparative analysis of essential oil composition of Iranian and Indian Nigella sativa L. extracted using supercritical fluid extraction and solvent extraction

The objective of this study was to compare the oil extraction yield and essential oil composition of Indian and Iranian Nigella sativa L. extracted by using Supercritical Fluid Extraction (SFE) and solvent extraction methods. In this study, a gas chromatography equipped with a mass spectrophotometer detector was employed for qualitative analysis of the essential oil composition of Indian and Iranian N. sativa L. The results indicated that the main fatty acid composition identified in the essential oils extracted by using SFE and solvent extraction were linoleic acid (22.4%–61.85%) and oleic acid (1.64%–18.97%). Thymoquinone (0.72%–21.03%) was found to be the major volatile compound in the extracted N. sativa oil. It was observed that the oil extraction efficiency obtained from SFE was significantly (P<0.05) higher than that achieved by the solvent extraction technique. The present study showed that SFE can be used as a more efficient technique for extraction of N. Sativa L. essential oil, which is composed of higher linoleic acid and thymoquinone contents compared to the essential oil obtained by the solvent extraction technique.

Effect of an orally formulated processed black cumin, from Iranian traditional medicine pharmacopoeia, in relieving symptoms of knee osteoarthritis: A prospective, randomized, double-blind and placebo-controlled clinical trial

AIM

Osteoarthritis is a global health problem, especially for the elderly. A good replacement for non-surgical treatments is the use of traditional medicines. We selected a revere plant (Nigella sativa L.), a widely utilized medicinal herb for the treatment of inflammatory conditions, from the Iranian traditional medicine (ITM) pharmacopoeia with proven anti-inflammatory and analgesic actions.

METHODS

We performed a prospective, randomized, double-blind, and placebo-controlled clinical trial, in order to investigate whether the herb is useful in alleviating the symptoms of knee osteoarthritis. American College of Rheumatology clinical criteria were the basis of diagnosis, while the Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire was considered as the main outcome measure. One hundred and ten eligible patients were assigned to receive a placebo or an active intervention (2 g/day of processed N. sativa seed powder in divided doses). Acetaminophen tablets were the rescue medicine. Finally, 40 patients in the placebo group and 37 patients in the active group completed the trial and were included in the statistical analysis.

RESULTS

Both cohorts demonstrated statistically significant within-group differences (P < 0.05) in some subscales that were more prominent in the active group without any considerable adverse effects. Nevertheless, KOOS score results and the mean number of acetaminophen tablets used by patients showed no statistically significant between-group differences.

CONCLUSIONS

It can be concluded that future programmed studies with larger sample sizes, longer follow-up periods, and other forms of N. sativa seeds as an active intervention is necessary to evaluate its efficacy in relieving the symptoms of knee osteoarthritis.

Responses of Nigella sativa L. to Zinc Excess: Focus on Germination, Growth, Yield and Yield Components, Lipid and Terpene Metabolism, and Total Phenolics and Antioxidant Activities

A comprehensive analysis of the responses of Nigella sativa L. to elevated zinc concentrations was assessed in pot experiments. Zn excess supply did not affect the germination but drastically reduced radicle elongation. A concentration-dependent reduction in all growth parameters, yield, and yield components was observed. With the increasing Zn concentrations, total lipid contents decreased and changes in fatty composition toward the production of saturated ones were underscored. Despite the reduction in the seeds essential oil yield, a redirection of the terpene metabolism toward the synthesis of oxygenated compounds has been evidenced. A significant increase in the total phenols and flavonoids contents concomitant with improved antioxidant activities has also been found. Collectively, these results highlight the possible use of N. sativa L. in phytoremediation applications, on the one hand, and that Zn excess could represent an excellent alternative to improve the nutritional attributes of this important species, on the other hand.

(Lady-in-a-Mist) Seeds

This study was performed to evaluate the phenolic profile, antioxidant and diuretic effects of black cumin and lady-in-a-mist seeds. In the phenolic profile, differences between the two species are significant. Qualitative and quantitative analyses of the phenolic compounds were performed using a HPLC-UV/MS method. Hyperoside was the only identified flavonoid glycoside (1.08 ± 0.01 μg∙g⁻¹ dw plant material), in the N. damascena extract. Regarding the flavonol profile, kaempferol was identified before the hydrolysis, only in the N. sativa extract (6.06 ± 0.02 μg∙g⁻¹ dw plant material) and quercetin only in N. damascena seeds (14.35 ± 0.02 μg∙g⁻¹ dw plant material). The antioxidant potential of the two species was tested through several electron transfer assays, which indicated, excepting for the FRAP assay, N. damascena as exhibiting a higher free radical scavenging activity. The diuretic activity of the two extracts was tested using a rat-experimental model on acute diuresis. Administration of the ethanolic extract of N. sativa (100 mg∙kg⁻¹) resulted in a significant increase in urine volume, although less than found with the reference drug; in addition N. damascena extract did not present a diuretic effect. In reference to the elimination of Na⁺, K⁺ and uric acid, the black cumin extract exhibited a higher natriuretic than kaluretic effect and a similar uricosuric effect with control and N. damascena. For N. damascena, the Na⁺/K⁺ ratio was sub unitary, but not due to an increasing of the kaluretic effect, but mostly to a decrease of Na⁺ excretion.

Increased 5-HT Levels Following Repeated Administration of Nigella sativa L. (Black Seed) Oil Produce Antidepressant Effects in Rats

The seeds of Nigella sativa L., commonly known as black seed or black cumin, and its extracts are used in folk medicine in the Middle East and in Asian countries for the promotion of good health and as a remedy for many ailments. These seeds have many acclaimed medicinal properties such as broncho-dilatory, immunopotentiating, analgesic, anti-inflammatory, and hypotensive. In the present study, the antidepressant activity following the repeated administration of Nigella sativa L. oil has been monitored using the forced swim test. Rats treated with Nigella sativa L. oil exhibited a significant increase in struggling time after oral administration of Nigella sativa L. oil (0.1 ml/kg/day) for four weeks. Nigella sativa L. oil increased brain 5-HT levels and decreased 5-HT turnover (5-HT/5-HIAA ratio). Levels of tryptophan increased significantly in the brain and plasma following the repeated administration of Nigella sativa L. oil. Nigella sativa L. oil showed a potential antidepressant-like effect.