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.

Saponins from Nigella glandulifera seeds attenuate collagen-induced rheumatoid arthritis in rats via the OPG/RANKL/NF-κB and Ang/Tie-2 pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Nigella glandulifera Freyn et Sint. (N. glandulifera) seeds are widely used in traditional Uyghur medicine for a variety of immuno-inflammatory diseases. The total saponins from N. glandulifera seeds (TSNGS) have been shown to have analgesic, antioxidant, and anti-inflammatory effects that can alleviate joint pain and swelling.

AIM OF THE STUDY

Rheumatoid arthritis (RA) is a chronic and progressive, debilitating autoimmune disease for which current treatments are not sufficiently effective and result in unsatisfactory side effects. This study aimed to mechanistically investigate the therapeutic effects of TSNGS on RA.

MATERIALS AND METHODS

Qualitative analysis of TSNGS was performed using ultra-high-performance liquid chromatography-Q-Orbitrap-high-resolution mass spectrometry. Rats with collagen-induced arthritis (CIA), IL-1β-induced HFLS-RAs, and VEGF-induced HUVECs were analyzed to determine the efficacy and mechanism of TSNGS on RA.

RESULTS

Twenty-one compounds were identified in TSNGS. TSNGS (10, 50, or 250 mg/kg) reduced the severity of arthritis, indicated by a lower arthritis score, reduced paw swelling, and body weight in rats with CIA. TSNGS ameliorated histopathological changes involving inflammatory infiltration, bone degeneration, and angiogenesis in knee and ankle joints. TSNGS improved the immuno-inflammatory response by restoring the levels of the cytokines IFN-γ, TNF-α, IL-1β, IL-6, IL-17A, IL-4, and IL-10, and increasing the number of CD4⁺CD25⁺ Tregs in the peripheral circulation and Foxp3 levels in knee joints in rats with CIA. Furthermore, TSNGS increased the OPG/RANKL ratio and downregulated p-p65 in serum and joint synovia. Inhibition of angiogenesis by TSNGS was associated with recovery of the angiogenesis-related Ang/Tie-2 signaling pathway.

CONCLUSIONS

It was established that TSNGS provides a therapeutic effect on RA by alleviating synovitis, bone degeneration, and angiogenesis via the OPG/RANKL/NF-κB and Ang/Tie-2 pathways and may be used for the treatment of RA.

Biological Potentials and Phytochemical Constituents of Raw and Roasted Nigella arvensis and Nigella sativa

Nigella species are widely used to cure various ailments. Their health benefits, particularly from the seed oils, could be attributed to the presence of a variety of bioactive components. Roasting is a critical process that has historically been used to facilitate oil extraction and enhance flavor; it may also alter the chemical composition and biological properties of the Nigella seed. The aim of this study was to investigate the effect of the roasting process on the composition of the bioactive components and the biological activities of Nigella arvensis and Nigella sativa seed extracts. Our preliminary study showed that seeds roasted at 50 °C exhibited potent antimicrobial activities; therefore, this temperature was selected for roasting Nigella seeds. For extraction, raw and roasted seed samples were macerated in methanol. The antimicrobial activities against Streptococcus agalactiae, Streptococcus epidermidis, Streptococcus pyogenes, Candida albicans, Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, and Klebsiella oxytoca were determined by measuring the diameter of the zone of inhibition. The cell viability of extracts was tested in a colon carcinoma cell line, HCT-116, by using a microculture tetrazolium technique (MTT) assay. Amino acids were extracted and quantified using an automatic amino acid analyzer. Then, gas chromatography–mass spectrometry (GC–MS) analysis was performed to identify the chemical constituents and fatty acids. As a result, the extracts of raw and roasted seeds in both Nigella species showed strong inhibition against Klebsiella oxytoca, and the raw seed extract of N.arvensis demonstrated moderate inhibition against S. pyogenes. The findings of the MTT assay indicated that all the extracts significantly decreased cancer cell viability. Moreover, N. sativa species possessed higher contents of the measured amino acids, except tyrosine, cystine, and methionine. The GC–MS analysis of extracts showed the presence of 22 and 13 compounds in raw and roasted N. arvensis, respectively, and 9 and 11 compounds in raw and roasted N. sativa, respectively. However, heat treatment decreased the detectable components to 13 compounds in roasted N. arvensis and increased them in roasted N. sativa. These findings indicate that N. arvensis and N. sativa could be potential sources of anticancer and antimicrobials, where the bioactive compounds play a pivotal role as functional components.

Nigella and Milk Thistle Seed Oils: Potential Cytoprotective Effects against 7β-Hydroxycholesterol-Induced Toxicity on SH-SY5Y Cells

Oxysterols are assumed to be the driving force behind numerous neurodegenerative diseases. In this work, we aimed to study the ability of 7β-hydroxycholesterol (7β-OHC) to trigger oxidative stress and cell death in human neuroblastoma cells (SH-SY5Y) then the capacity of Nigella sativa and Milk thistle seed oils (NSO and MTSO, respectively) to oppose 7β-OHC-induced side effects. The impact of 7β-OHC, associated or not with NSO or MTSO, was studied on different criteria: cell viability; redox status, and apoptosis. Oxidative stress was assessed through the intracellular reactive oxygen species (ROS) production, levels of enzymatic and non-enzymatic antioxidants, lipid, and protein oxidation products. Our results indicate that 7β-OHC (40 µg/mL) exhibit pr-oxidative and pro-apoptotic activities shown by a decrease of the antioxidant enzymatic activities and an increase of ROS production, lipid, and protein oxidation end products as well as nitrotyrosine formation and caspase 3 activation. However, under the pre-treatment with NSO, and especially with MTSO (100 µg/mL), a marked attenuation of oxidative damages was observed. Our study suggests harmful effects of 7β-OHC consisting of pro-oxidative, anti-proliferative, and pro-apoptotic activities that may contribute to neurodegeneration. NSO and especially MTSO showed potential cytoprotection against the cytotoxicity of 7β-OHC.

Vapors of Volatile Plant-Derived Products Significantly Affect the Results of Antimicrobial, Antioxidative and Cytotoxicity Microplate-Based Assays

Volatile plant-derived products were observed to exhibit broad spectrum of biological effects. However, due to their volatility, results of conventional microplate-based bioassays can be significantly affected by the vapors. With aim to demonstrate this phenomenon, antimicrobial, antioxidant, and cytotoxic activities of three essential oils (Alpinia elegans, Cinnamomum iners, and Xanthostemon verdugonianus), one supercritical CO2 extract (Nigella sativa), and four plant-derived compounds (capsaicin, caryophyllene oxide, 8-hydroxyquinoline, and thymoquinone) were evaluated in series of experiments including both ethylene vinyl acetate (EVA) Capmat sealed and nonsealed microplates. The results clearly illustrate that vapor transition to adjoining wells causes false-positive results of bioassays performed in nonsealed microtiter plates. The microplate layout and a duration of the assay were demonstrated as the key aspects defining level of the results affection by the vapors of volatile agents. Additionally, we reported biological activities and chemical composition of essential oils from A. elegans seeds and X. verdugonianus leaves, which were, according to our best knowledge, analyzed for the first time. Considering our findings, certain modifications of conventional microplate-based assays are necessary (e.g., using EVA Capmat as vapor barrier) to obtain reliable results when biological properties of volatile agents are evaluated.

Chitosan coated synergistically engineered nanoemulsion of Ropinirole and nigella oil in the management of Parkinson's disease: Formulation perspective and In vitro and In vivo assessment

The research presented aims at developing Ropinirole hydrochloride (RHCl) nanoemulsion (NE) with nigella oil for Parkinson's disease (PD). In silico study was done to explore interactions of ropinirole and thymoquinone at receptor site (TNF-α and NFK-β). Ropinirole and Thymoquinone forms a hydrogen bond with residue Arginine 201 and residue Arginine 253 with a bond length of 1.89 Å and 2.30 Å at the NF-κβ receptor. NE was optimized using Central Composite Rotatable Design (CCRD). The globule size of chitosan coated NE, Polydispersity index (PDI) and zeta potential were 183.7 ± 5.2 nm, 0.263 ± 0.005, and 24.9 mV respectively. NE exhibited 85.28% transmittance showing the formulation was clear and transparent. TEM showed that NE had spherical globules with no aggregation. The formulation had a stable pH value of 5.8 ± 0.18. In vitro release and permeation studies exhibited 2 folds and 3.4 folds enhancement when compared with the drug suspension. Neurobehavioral activity and biochemical parameters corroborated well with the pharmacokinetic results. Histopathological study and immunohistochemical analysis were performed to get better picture of 6-OHDA induced toxicity and reversal of PD symptoms. Thus, the NE tailored is a promising synergistic approach yielding enticing outcomes for better management of PD related symptoms.

Profile of Fatty Acids, Tocopherols, Phytosterols and Polyphenols in Mediterranean Oils (Argan Oils, Olive Oils, Milk Thistle Seed Oils and Nigella Seed Oil) and Evaluation of their Antioxidant and Cytoprotective Activities

BACKGROUND

The effects of vegetable oils on human health depend on their components. Therefore, their profiles of lipid nutrients and polyphenols were determined.

OBJECTIVE

To establish and compare the fatty acid, tocopherol, phytosterol and polyphenol profiles of Mediterranean oils: cosmetic and dietary argan oils (AO; Morocco: Agadir, Berkane); olive oils (OO; Morocco, Spain, Tunisia); milk thistle seed oils (MTSO; Tunisia: Bizerte, Sousse, Zaghouane); nigella seed oil (NSO).

METHODS

The biochemical profiles were determined by gas chromatography-flame ionization, high performance liquid chromatography and gas chromatography, coupled with mass spectrometry as required. The antioxidant and cytoprotective activities were evaluated with the KRL (Kit Radicaux Libres) and the fluorescein diacetate tests on nerve cells treated with 7-ketocholesterol (7KC).

RESULTS

The fatty acid profile revealed high linoleic acid (C18:2 n-6) content in AO, OO, MTSO and NSO. The highest levels of oleic acid (C18:1 n-9) were found in AO and OO. The tocopherol profile showed that Agadir AO contained the highest amount of α-tocopherol, also present at high level in MTSO and Tunisian OO; Berkane AO was rich in γ-tocopherol. The phytosterol profile indicated that β-sitosterol was predominant in the oils, except AO; spinasterol was only present in AO. Polyphenol profiles underlined that OO was the richest in polyphenols; hydroxytyrosol was only found in OO; few polyphenols were detected in AO. The oils studied have antioxidant activities, and all of them, except NSO, prevented 7KC-induced cell death. The antioxidant characteristics of AO were positively correlated with procatechic acid and compestanol levels.

CONCLUSION

Based on their biochemical profiles, antioxidant and cytoprotective characteristics, AO, OO, and MTSO are potentially beneficial to human health.

In Vitro Human Dihydroorotate Dehydrogenase Inhibitory, Anti-inflammatory and Cytotoxic Activities of Alkaloids from the Seeds of Nigella glandulifera

Four new dolabellane-type diterpene alkaloids, glandulamines A - D (1:  - 4: ), together with twelve known compounds (5:  - 16: ), were isolated from the seeds of Nigella glandulifera using repeated column chromatography and semipreparative HPLC. The structures of 1:  - 16: were elucidated based on NMR data analysis, HRMS experiments and other spectroscopic interpretations. The absolute configuration of 5: was determined by single-crystal X-ray diffraction data for the first time. Compounds 10: and 12: showed human dihydroorotate dehydrogenase inhibitory activity with IC₅₀ values of 61.1 ± 5.3 and 45.9 ± 3.0 µM, respectively. Molecular docking of the active compound 12: and positive control teriflunomide on the inhibitor-binding site of human dihydroorotate dehydrogenase was subsequently performed to visualize the interaction pattern. In addition, compounds 8: and 10: exhibited inhibitory effects against lipopolysaccharide-induced nitric oxide production with inhibition rates of 61 and 41%, respectively, at the concentration of 10 µM. Compounds 9: and 12: showed cytotoxic activities with cell viability varying from 29 ~ 57% at 100 µM against T98G, U87, U251, and GL261 glioma cancer cell lines. These data provide new insights on the pharmacologically active compounds of this plant widely used in folk medicine.

Protective effects of traditional Uighur medicine-seeds of Nigella glandulifera Freyn extracts against ccl4-induced acute hepatic injury in mice

To explore the protective effects of Traditional Uighur medicine Seeds of Nigella glandulifera Freyn (SNF) extracts against CCl4-induced acute hepatic injury in mice. Hepatic injury mice models induced by intraperitoneal injection of 0.1% CCl4 olive oil were established. Liver and spleen coefficient, Serum ALT and AST activities, SOD, GSH-Px activities and MDA content in hepatic homogenate were measured and the hepatic histological changes were observed by optical microscope. Serum activities of ALT (P<0.01) and AST (P<0.05) in Alcohol extraction group was decreased; Activity of hepatic homogenate SOD increased in Alcohol extraction group and Water extraction group significantly (P<0.05). Content of MDA was decreased in Alcohol extraction group (P<0.01). Water extracts of SNF have obvious protective effects on hepatic injury induced by CCl4 in mice.

Three new alkaloids from the seeds of Nigella glandulifera

Three new alkaloids namely 8-(4-hydroxyphenyl)-6-methoxy-3,4-dihydroisoquinolin-1(2H)-one (1), 4-aminonigellidine (2), and N-[(4-hydroxy-2-isopropyl-5-methyl)]phenylurea (3), along with six known ones (4-9), were isolated from the seeds of Nigella glandulifera. The structures of 1-3 were determined through spectroscopic analyses (HRESIMS, 1D/2D NMR). Compound 1 was a rare isoquinolinone alkaloid with phenyl substituted at C-8.

Neuroprotective effects of Nigella sativa on experimental spinal cord injury in rats

The aim of this study was to investigate the possible beneficial effects of Nigella sativa (NS) in comparison to methylprednisolone on experimental spinal cord injury (SCI) in rats. SCI was performed by placing an aneurysm clip extradurally at the level of T11-12. Rats were neurologically tested over 24 h after trauma and spinal cord tissue samples were harvested for both biochemical and histopathological evaluation. The neurological scores of rats were not found to be different in SCI groups. SCI significantly increased the spinal cord tissue malondialdehyde (MDA) and protein carbonyl (PC) levels, however SCI decreased superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) enzyme activities compared to the control. Methylprednisolone and NS treatment decreased tissue MDA and PC levels and prevented inhibition of SOD, GSH-Px and CAT enzymes in the tissues. The most significant results were obtained when NS was given. In SCI and placebo groups, the neurons of spinal cord tissue became extensively dark and degenerated with picnotic nuclei. The morphology of neurons in methylprednisolone and NS-treated groups were well protected, however, not as well as the neurons of the control group. The number of neurons in the spinal cord tissue of the SCI and placebo groups was significantly less than the control, laminectomy, methylprednisolone and NS-treated groups. In conclusion, NS treatment might be beneficial in spinal cord tissue damage, and therefore shows potential for clinical implications.

Effects of Thymoquinone on the Pharmacokinetics and Pharmacodynamics of Glibenclamide in a Rat Model

Glibenclamide and thymoquinone plasma concentrations were analysed using a sensitive RP-HPLC method, and non-compartmental model pharmacokinetic parameters were calculated. The maximum reduction in blood glucose level was observed 3 hours following glibenclamide administration, which reached 47.4% of baseline, whereas it was reduced by 53.0% to 56.2% when co-administrated with thymoquinone. Plasma concentration of glibenclamide was increased by 13.4% and 21.8% by the co-administration of thymoquinone as single and multiple doses, respectively (P<0.05). The AUC and TI/2 of glibenclamide were also increased respectively by 32.0% and 17.4% with a thymoquinone single dose, and by 52.5% and 92.8% after chronic treatment. Furthermore, diabetic rats treated with thymoquinone demonstrated a marked decrease in hepatic protein expressions of CYP3A2 and CYP2C 11 enzymes that are responsible for the metabolism of glibenclamide. The current data suggest that thymoquinone exhibits a synergistic effect with glibenclamide on glucose level, which could be explained by reducing CYP450 activity at the protein level.

Physicochemical and phytochemical standardization with HPTLC fingerprinting of Nigella sativa L. seeds

This study was designed to perform the physicochemical and phytochemical standardization with HPTLC fingerprinting of Nigella sativa seeds in order to establish the standard pharmacognostical parameters of this miracle herb. Different parameters like extractive values; total ash value, acid insoluble ash value and water soluble ash value, moisture content, loss on drying, pH values of Nigella sativa seeds were performed. Preliminary phytochemical screening was done to detect different phytoconstituents by using the Harborne's phytochemical methods. Quantification of phenolic and flavonoid contents, determination of pesticides residues, aflatoxin and heavy metals were also carried out. HPTLC fingerprinting of methanolic extract was performed using CAMAG-HPTLC system connected with win CAT software. Preliminary phytochemical screening of the extracts in different solvent revealed the presence of carbohydrates, phenolic compounds, flavonoids, alkaloids, proteins, saponins, lipids, sterols and tannins. Total flavonoid and phenolic contents in methanolic extract was found to be 1.4 mg/gm and 9.8 mg/gm extract respectively. Concentrations of heavy metals were found within acceptable limits. Pesticides residues and aflatoxins were not detected. The physicochemical and phytochemical standards along with HPTLC fingerprint profile established as an outcome of this research may be utilized as substantial data for identification, purification and standardization of Nigella sativa seeds.

Highly conjugated norditerpenoid and pyrroloquinoline alkaloids with potent PTP1B inhibitory activity from Nigella glandulifera

Three norditerpenoid alkaloids, nigelladines A-C (1-3), and one pyrroloquinoline alkaloid, nigellaquinomine (4), all possessing new skeletons with highly conjugated systems, were isolated from Nigella glandulifera. The 8aS-configuration for 1 and 2 was determined by comparison of the experimental and calculated electronic circular dichroism spectra. These alkaloids exhibited potent protein tyrosine phosphatase 1B (PTP1B) inhibitory activity but are devoid of cytotoxicity against the A431 cell line at 100 μM.

[Study on chemical constituents of Nigella glandulifera]

OBJECTIVE

To study the chemical constituents of Nigella glandulifera.

METHODS

Compounds were isolated and purified from extracts of Nigella glandulifera by extraction and different kinds of column chromatography. Their structures were determined on the basis of the physicochemical properties and spectral analysis.

RESULTS

Six compounds were identified as glycerol tripalmtate (1), 2-methyl-5-isopropyl pairphenol (2), stigmasterol (3), 1-O-hexadecanolenin (4), nigellidine (5) and nigeglanine (6).

CONCLUSION

Compounds 1 and 5 are obtained from this plant for the first time, and compound 2 is a new compound.

[HPLC fingerprint spectrum of xinjiang uyghur medicine Nigella glandulifera seed]

OBJECTIVE

To establish the HPLC fingerprint spectrum of Nigella glandulifera seed identification.

METHODS

The chromatographic system consisted of a Shim-pack ODS C18 column (150 mm x 4.6 mm, 5 microm) and a mobile phase of acetonitrile-0.1% formic acid in condition of gradient elution,The detection wavelength was 280 nm. The column temperature was 30 degrees C.

RESULTS

Detected the HPLC fingerprint spectrum of 10 batches samples Nigella glandulifera seed from Xinjiang; Calibrated 18 characteristic peaks. The result was in accordance with the technical requirement of fingerprint spectrum. The similarity calculation software showed that the similarity was higher than 0. 95.

CONCLUSION

The HPLC fingerprint spectrum of Nigella glandulifera seed can be used as an identification method. It may provide the basis for quality control of Nigella glandulifera seed.

African descents are more sensitive than European descents to the antitumor compounds α-hederin and kalopanaxsaponin I

α-Hederin, a natural triterpene saponin and its derivative kalopanaxsaponin I (ksI) exhibit cytotoxicity against various cancer cell lines and IN VIVO tumors. We studied the genetic variants contributing to the activity of these two anticancer compounds. Cell lines derived from 30 trios of European descent (Centre d'Etude du Polymorphisme Human, CEPH; CEU) and 30 trios of African descent (Yoruban, YRI) were used. Cytotoxicity was determined as inhibition of cell growth at increasing concentrations of α-hederin or ksI for 24 h. In comparison to the European, the Yoruban populations revealed a higher sensitivity to α-hederin and to ksI that can be attributed to several unique SNPs. These SNPs are located near 111 and 130 genes in the European and the Yoruban populations, respectively, raising the possibility that some of these genes contribute to the differential sensitivity to these compounds.

[Analysis on chemical components of volatile oil and determination of thymoquinone from seed of Nigella glandulifera]

OBJECTIVE

To analysis chemical components of volatile oil from the seed of Nigella glandulifera (NG), comparing them with those from the seed of foreign N. sativa (NS) and N. damascene (ND), and to quantify thymoquinone in the volatile oil extracted by hydrodistillation (HD) from the seed of NG.

METHOD

The volatile oil was extracted by supercritical CO2 extraction (SFE-CO2 ) and HD from the seed of NG and its chemical components was analysed by GC-MS, the relative percentage of components were determined by peak aera normalization method and compare with those of the seed of NS and ND. The content of the thymoquinone in the volatile oil was determined by one point external standard method.

RESULT

In terms of the volatile compounds, p-cymene is the major component of NG and NS, their relative percentage contents are 33.75% and 61.48%, respectively. beta-Elemene is the major component of ND, its relative percentage content is 73.24%. The relative percentage contents of thymoquinone are 3.73% (HD), 3.80% and 0.08% in NG, NS and ND, respectively. Linoleic acid is a major component of volatile oil by SFE-CO2 in NG, but its content of p-cymene is lower. The absolute percentage content of thymoquinone is 1.58% by HD in volatile oil of NG.

CONCLUSION

There are comparatively large differences of volatile components in NG, NS and ND.

Different isolation methods for determination of composition of volatiles from Nigella damascena L. seeds

Volatile organic compounds (VOCs) from seeds of Nigella damascena L. were isolated using different techniques. The yield, as well as the qualitative and quantitative composition of the oils, was strongly influenced by the isolation method. In the hydrodistilled essential oil, the major components were the sesquiterpene hydrocarbons beta-elemene (59.1%), beta-selinene (12.8%) and alpha-selinene (12.6%). Conventional solvent extraction, followed by hydrodistillation, resulted in a volatile oil with a different composition than that of the hydrodistilled oil. The extracted oils predominantly contained sesquiterpene hydrocarbons, but also methyl anthranilate derivatives. By means of HS-SPME, it was possible to analyze not only sesquiterpenes and anthranilates, but also monoterpenes and the most volatile compounds, for example, the lower fatty acid (butyric, capronic) esters, which determine the characteristic sweet scent of N. damascena seeds. Using all testing methods, 55 compounds were identified, 40 of which are new for N. damascena seed VOCs.

Ancient nigella seeds from Boyali Höyük in north-central Turkey

AIM OF THE STUDY

The seeds of nigella (black cumin) (Nigella sativa L.) have been widely used as a natural remedy, either alone or in combination with bee products, for the treatment of many acute as well as chronic conditions for centuries, especially in the Middle East and Southeast Asia. In consideration of potential utilization, in recent years the seeds have been extensively studied in terms of pharmacological effects. It has been shown that the seeds have significant effects on multiple biological systems. In addition, the protective roles of the seeds with bee products (honey and wax) have been recently proved. This study reports the palaeoethnobotanical find of nigella seeds recovered in a pilgrim flask from the Old Hittite Period level of Boyali Höyük (Mound), dating from around 1650 BC, in north-central Turkey. The study also deals with a comparison between the chemical properties of the Boyali Höyük nigella seeds (ancient seeds) and those of modern nigella seeds. The results of chemical analysis of the debris found in the pilgrim flask to test the presence of bee product are also presented here.

MATERIALS AND METHODS

All macro-remains found in the pilgrim flask were first examined under a zoom stereomicroscope for specific determination and all were identified as nigella seeds using the reference collection of modern seeds. Ethyl alcohol and dichloromethane (Aldrich, Buch-Switzerland) were used for the extraction of the ancient seeds and modern nigella seeds to trace both polar and non-polar chemical compounds by a Gas Chromatography-Mass Spectrometer (GC-MS) system. Characterization of the chemical compounds in propolis extracts was also made by GC-MS.

RESULTS

The GC-MS chromatograms showed that the ancient and modern seed samples were similar in essential oil acids. Many organic compounds of bee products, such as wax and phenolic antioxidants, were also detected in the container.

CONCLUSION

The results of this study indicated that the Hittite pilgrim flask contained a pure cache of nigella seeds mixed with bee products, wax and propolis. There has been no direct archaeological evidence for medicinal use of nigella seeds with bee products by the inhabitants of Boyali Höyük or the Hittities so far. However, in view of the folkloric use of nigella seeds in combination with bee products for treatments of disorders and promotion of health, it is thought that the Boyali Höyük material would represent a remedy used by the Hittites in Anatolia about 3600 years ago.

A study on artifacts formation in the Thai traditional medicine Prasaplai

The artificial formation of three fatty acid esters, ( E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl linoleate ( 1), ( E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl oleate ( 2) and ( E)-4-(3,4-dimethoxyphenyl)but-3-en-1-yl palmitate ( 3) originating during storage by the interaction of components in Prasaplai preparation was investigated. The artifacts were not formed when 0.1 mL of water or more was added to 1.0 g of the mixture (1 : 1) of Zingiber cassumunar and Nigella sativa even when stored for 20 days. This result showed that water was able to stop the esterification reaction. The formation of the artifacts by chemical reaction under water-free conditions was evaluated. ( E)-4-(3,4-dimethoxyphenyl)but-3-en-1-ol was mixed with linoleic acid in the presence of anhydrous Na (2)SO (4) and stored in a dessicator for 7 days. The artifact ( 1) was formed in 6.0 % yield. It was concluded that a water-free environment is necessary for the direct chemical formation of the artificial esters.

Inhibition of melanogenesis by dioctyl phthalate isolated from Nigella glandulifera Freyn

Although a number of melanogenesis inhibitors have recently been reported and used as cosmetic additives, none is completely satisfactory, leaving a need for novel skin-depigmenting agents. Thus, to develop a novel skin-depigmenting agent from natural sources, the inhibition of melanogenesis by Chinese plants was evaluated. A methanolic extract of Nigella glandulifera Freyn was found to inhibit the melanin synthesis of murine B16F10 melanoma cells by 43.7% and exhibited a low cytotoxicity (8.1 %) at a concentration of 100 microg/ml. Thus, to identify the melanogenesis-inhibiting mechanism, the inhibitory activity towards tyrosinase, the key enzyme of melanogenesis, was further evaluated, and the results showed inhibitory effects on the activity of intracellular tyrosinase yet not on mushroom tyrosinase. Finally, to isolate the compounds with a hypopigmenting capability, activity-guided isolation was performed, and Dioctyl phthalate identified as inhibiting melanogenesis.

Anticlastogenic activity of thymoquinone against benzo(a)pyrene in mice

Thymoquione (TQ), the main constituent of the volatile oil of Nigella sativa seeds, has been shown to protect mice against benzo(a)pyrene [B(a)P]-induced forestomach carcinogenesis. The present investigation was undertaken to study the possible chemopreventive activity of TQ, supplemented in the drinking water, against B(a)P-induced chromosomal aberrations (CAs) in mouse bone marrow cells. Male Swiss albino mice received TQ (0.01% in drinking water) daily for 28 days. The daily dose of TQ was estimated to be 10mg/kg based on the calculated average daily water consumption by mice. From day 9, the carcinogen, B(a)P, was given by gastric intubation at dose level of 50mg/kg on alternative days for a total of 8 doses. On day 29, all mice were transferred to a normal drinking tap water. Control groups received corn oil vehicle, TQ alone or B(a)P alone. All mice were sacrificed at 12 weeks after the end of the treatment. Chromosome preparations were made of bone marrow. Cytogenetic end points screened were the frequencies of CAs and damaged cells induced. Daily intake of TQ after and before or during exposure to B(a)P significantly reduced the frequencies of CAs and damaged cells compared to the highly clastogenic activity of B(a)P alone.

Effects ofNigella orientalis andN. segetalis fixed oils on blood biochemistry in rats

Nigella orientalis and N. segetalis fixed oils were administered orally (1 mL/kg/day) to Wistar Kyoto rats for 4 weeks. The effects of the oils on biochemical parameters were compared with a control group that received distilled water under identical conditions. LDL-cholesterol level was decreased significantly in both oil groups while serum total cholesterol and VLDL-cholesterol were decreased significantly following administration of only N. orientalis fixed oil when compared with the control group. The HDL-cholesterol levels were increased significantly in both oil groups.N. orientalis fixed oil significantly reduced Aspartateaminotransferase (AST), Alkaline Phosphatase (ALP), bilirubin and urea levels in rats. There was an increase in the albumin, uric acid and mean corpuscular volume (MCV) concentrations, while the mean corpuscular hemoglobin concentration (MCHC) and RDW (red cell distribution width) levels decreased significantly. In N. segetalis fixed oil treated rats, the levels of ALP, Blood Urea Nitrogen (BUN), MCHC, RDW were decreased significantly, whereas a significant increase was found in albumin, fibrinogen, Hematocrit (HCT) and MCV levels. The effects of 4 weeks oral intake of N. orientalis and N. segetalis fixed oils on blood malondialdehyde (MDA) and total antioxidant status (TOS) were also investigated in rats. The study showed that the oils had no significant effect on MDA production. N. orientalis and N. segetalis fixed oils caused a significant increase in the total antioxidant status in rats.

Effects of aqueous and macerated extracts from Nigella sativa on guinea pig isolated heart activity

Several therapeutic effects including those on digestive and gynaecological disorders, against asthma and dyspnea have been described for the seeds of Nigella sativa. In the present study, the effects of aqueous and macerated extracts from Nigella sativa on heart rate and contractility of the isolated heart were examined. Isolated guinea-pig hearts were perfused through aorta in the Langendorff mode. Heart rate (HR) and contractility were determined on the presence of four concentrations of aqueous and macerated extract from Nigella sativa (0.5, 1.0, 2.0 and 5.0 mg%) and diltiazem, a calcium channel blocker (0.1, 1, 10 and 100 microM) in comparison with baseline values in two different groups of experiments as follows: 1) Perfused heart with ordinary Krebs solution (group 1 experiments, n = 9). 2) Perfused heart with calcium free Krebs solution (group 2 experiments, n = 8). In group 1 three higher concentrations of diltiazem (1, 10 and 100 microM) and both extracts (1.0, 2.0 and 5.0 mg%) showed a significant reduction in heart rate (P < 0.001). However, only two larger concentrations of diltiazem (10 and 100 [microM) and macerated extract (2.0 and 5.0 mg%) and three concentrations of the aqueous extract (1.0, 2.0 and 5.0 mg%) caused a significant reduction in heart contractility in this group (P < 0.001). In group 2 only 100 microM diltiazem, caused significant reduction in heart contractility. However, two concentrations of macerated extract (2.0 and 5.0 mg%) and three higher concentrations of aqueous extract (1.0, 2.0 and 5.0 mg%) caused significant reductions in heart rate and contractility in this group (p < 0.05 to p < 0.001). There were significant negative correlations between concentrations of both extracts and diltiazem and their effect on heart rate and contractility in both groups (p < 0.01 to p < 0.001). These results showed a potent inhibitory effect of both extracts from Nigella sativa on both heart rate and contractility of guinea pig heart that was comparable and even higher than that of diltazem. The results of the present study may be due to calcium channel inhibitory or an opening effect for the plant on potassium channels of the isolated heart.

Gastroprotective activity of Nigella sativa L oil and its constituent, thymoquinone against acute alcohol-induced gastric mucosal injury in rats

AIM

To evaluate the role of reactive oxygen species in the pathogenesis of acute ethanol-induced gastric mucosal lesions and the effect of Nigella sativa L oil (NS) and its constituent thymoquinone (TQ) in an experimental model.

METHODS

Male Wistar albino rats were assigned into 4 groups. Control group was given physiologic saline orally (10 mL/kg body weight) as the vehicle (gavage); ethanol group was administrated 1 mL (per rat) absolute alcohol by gavage; the third and fourth groups were given NS (10 mL/kg body weight) and TQ (10 mg/kg body weight p.o) respectively 1 h prior to alcohol intake. One hour after ethanol administration, stomach tissues were excised for macroscopic examination and biochemical analysis.

RESULTS

NS and TQ could protect gastric mucosa against the injurious effect of absolute alcohol and promote ulcer healing as evidenced from the ulcer index (UI) values. NS prevented alcohol-induced increase in thiobarbituric acid-reactive substances (TBARS), an index of lipid peroxidation. NS also increased gastric glutathione content (GSH), enzymatic activities of gastric superoxide dismutase (SOD) and glutathione-S-transferase (GST). Likewise, TQ protected against the ulcerating effect of alcohol and mitigated most of the biochemical adverse effects induced by alcohol in gastric mucosa, but to a lesser extent than NS. Neither NS nor TQ affected catalase activity in gastric tissue.

CONCLUSION

Both NS and TQ, particularly NS can partly protect gastric mucosa from acute alcohol-induced mucosal injury, and these gastroprotective effects might be induced, at least partly by their radical scavenging activity.

The antioxidative and antihistaminic effect of Nigella sativa and its major constituent, thymoquinone on ethanol-induced gastric mucosal damage

The aim of this study was to assess the possible protective effects of Nigella sativa (NS) and its constituent, thymoquinone (TQ) on ethanol-induced gastric mucosal damage in an experimental model. Forty male rats aged four months were divided into four groups (each group containing ten animals); the control group received physiologic saline (10 ml kg(-1)) and the ethanol group had taken 1 ml (per rat) absolute alcohol by gavage. The third and fourth groups also received NS (500 mg kg(-1)) and TQ (10 mg kg(-1)) by gavage 1 h before alcohol administration, respectively. Both drugs (NS and TQ) could protect the gastric mucosa against the injurious effect of absolute alcohol and promote ulcer healing as evidenced from the ulcer index values. Gastric damage was confirmed histomorphometrically by significant increases in the number of mast cells (MC) and gastric erosions in ethanol treated rats. The NS treatment significantly decreased the number of MC and reduced the area of gastric erosions. Likewise, TQ treatment was also able to reduce the number of MC and the gravity of gastric mucosal lesions, but to lesser extent compared to NS. Gastric tissue histamine levels and myeloperoxidase activities were found to be increased in ethanol treated rats, and NS or TQ treatment reversed these increases. Results obtained from this study suggest that both drugs, particularly NS could partly protect gastric mucosa from acute alcohol-induced mucosal injury, and these gastroprotective effects could be due to their antiperoxidative, antioxidant and antihistaminic effects.

Nigella sativa (black seed) oil does not affect the T-helper 1 and T-helper 2 type cytokine production from splenic mononuclear cells in allergen sensitized mice

Nigella sativa Linn. (Ranunculaceae) is known to have beneficial effects on a wide range of diseases including asthma. However, the mechanism of action in asthma and other allergic diseases is not entirely clear. The present study was planned to evaluate the effects of Nigella sativa on cytokine production of splenic mononuclear cells in ova-sensitized mice. Nineteen two-month-old BALB/c mice were given 0.3 mL of Nigella sativa oil by oro-eosophageal cannula once a day for a month. The control group consisting of 10 mice took 0.3 mL of 0.9% saline solution by the same route for the same period. In the third week of the study, all mice were sensitized by means of intraperitoneal injections of 20 microg of ovalbumin (OVA-Grade VI, Sigma). Ova injections were repeated three times with 7-day intervals. After another week, all mice were sacrificed by means of cervical dislocation. Then the splenic mononuclear cells (MNCs) of mice were cultured with OVA or Concavalin A (Con-A). From the culture supernatants, IL-4, IL-10 and IFN-gamma were assessed by means of ELISA. The cytokine production of splenic MNCs of mice that were given Nigella sativa for 30 days was not significantly different than those who took saline solution instead. In conclusion, Nigella sativa oil seems not to have an immunomodulatory effect on Th1 and Th2 cell responsiveness to allergen stimulation.

Cytotoxic effects of a decoction of Nigella sativa, Hemidesmus indicus and Smilax glabra on human hepatoma HepG2 cells

A decoction of Nigella sativa seeds, Hemidesmus indicus root and Smilax glabra rhizome is used by traditional medical practitioners in Sri Lanka to treat cancer and has been shown to prevent chemically induced carcinogenesis in rats. The cytotoxicity of the decoction and the individual plant extracts were tested on the human hepatoma HepG2 cell line. The effects of 24 h incubation with different concentrations (0--50 mg/ml) of the extracts on HepG2 cells were determined. Results from MTT and SRB assays, and [(14)C]-leucine and [(3)H]-thymidine uptake demonstrated that the decoction had a strong dose-dependent cytotoxic activity. The greatest inhibitory effects were observed on DNA synthesis with both the decoction (91+/-S.E. 3.7% inhibition) and N. sativa plant extract (88+/-3.8%) even at low concentrations (5 mg/ml). The three individual plant extracts were cytotoxic in the order of potency N. sativa>H. indicus>S. glabra. Flow cytometric analysis using Annexin V and propidium iodide staining showed that after 24 h exposure to the decoction, cells were in the late stage of apoptosis and/or necrosis. Further experiments are worthwhile to determine the anticancer potential of this plant decoction and its components.

[Studies on chemical constituents in the seeds of Nigella glandulifera]

OBJECTIVE

To investigate the chemical constituents in the seeds of Nigella glandulifera.

METHOD

The chemical constituents were isolated and repeatedly purified on silica gel column. They were identified and structurally elucidated by means of physio-chemical constants and spectral analysis.

RESULT

Nine compounds were identified as nigellamose (I), alpha-hederin (II), 3-O-[beta-D-xylopyranosyl-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinpyranosyl]-hederagenin (III), sucrose (IV), stearic acid (V), 1-O-hexadecanolenin (VI), beta-sitosterol (VII), daucosterol (VIII) and p-hydroxybenzoic acid (IX).

CONCLUSION

I, II, III, VI, VIII and IX were obtained from the plant for the first time, and I is a new compound.

Total Synthesis of Nigellicine and Nigeglanine Hydrobromide

[reaction: see text] The first syntheses of the pyridazinoindazolium alkaloids nigellicine and nigeglanine hydrobromide via a common intermediate are described. Ortho-lithiation/acylation and the direct amination of an isatin ring system are the key steps in the synthesis.

Effects of Nigella unguicularis fixed oil on blood biochemistry and oxidant/antioxidant balance in rats

In the present study, Nigella unguicularis (Lam.) Spenner (Ranunculaceae) (Nu) fixed oil was administered orally to Wistar Kyoto rats for 4 weeks. The effects of the oil on serum lipid profile, haematological parameters and oxidant/antioxidant balance were investigated. The study showed that daily administration of the oil (1 ml/kg orally for 4 weeks) caused a significant decrease in serum total cholesterol, VLDL-cholesterol, triglycerides, glucose levels and a significant elevation of serum high-density lipoprotein level. The serum transaminases ( aspartate transaminase (AST), alanine transaminase (ALT)), alkaline phosphatase, bilirubin, blood urea nitrogen, urea, mean corpuscular haemoglobin concentration decreased significantly while albumin, mean corpuscular volume and fibrinogen levels increased significantly compared to control values. The administration of the oil (1 ml/kg orally for 4 weeks) caused a significant increase total antioxidant status in rats. Treatment with Nigella unguicularis oil did not effect malondialdehyde (MDA) concentrations. It is concluded that Nigella unguicularis oil possesses favourable metabolic effects on blood biochemistry and oxidant/antioxidant balance in rats.

A new alkaloid and its artificial derivative with an indazole ring from Nigella glandulifera

A new compound, nigeglanine (1), and its new artificial derivative (1a), were isolated from the seeds of Nigella glandulifera, together with a known aporphine alkaloid, fuzitine (2). Their structures were established by spectral analysis, including two-dimensional (2D)-NMR spectroscopy. Nigeglanine (1) is the third natural product determined to contain an indazole nucleus.

Gastroprotective activity of Nigella sativa oil and its constituent, thymoquinone, against gastric mucosal injury induced by ischaemia/reperfusion in rats

Ischaemia/reperfusion (I/R) induced gastric lesion, is known to be linked with free radical (FR) formation. Therefore, this model was used to assess the antioxidant effects of Nigella sativa oil (N.O) and thymoquinone (TQ) on gastric mucosal redox state and gastric lesions, 1 and 24 h after reperfusion. Male Wistar rats were subjected to I/R and were injected with either N.O (2.5 and 5 ml/kg, p.o) or TQ (5, 20, 50 and 100 mg/kg, p.o). The results showed that I/R elevated the levels of lipid peroxide (LPX) and lactate dehydrogenase (LDH), while decreased those of reduced glutathione (GSH) and superoxide dismutase (SOD). These biochemical changes were accompanied by an increase in the formation of gastric lesions, which was reduced by either treatment. N.O tended to normalize the level of LDH, GSH and SOD. However, its effect to restore LPX was only seen 24 h after reperfusion. Moreover, the aforementioned parameters were nearly reinstated by TQ. On the other hand, high doses of TQ (50 and 100 mg/kg) severely reduced the GSH content, 1 h after reperfusion. These results indicate that both N.O and TQ possess gastroprotective effect against gastric lesions which may be related to the conservation of the gastric mucosal redox state.

Stimulatory effects on Na+ transport in renal epithelia induced by extracts of Nigella arvensis are caused by adenosine

Effects of the extract of Nigella arvensis (NA) seeds on transepithelial Na+ transport were studied in cultured A6 toad kidney cells by recording short-circuit current (Isc),transepithelial conductance (GT), transepithelial capacitance (CT) and fluctuation in Isc. Apical application of NA extract had merely a small stimulatory effect on Na+ transport, whereas basolateral administration markedly increased Isc, GT and CT. A maximal effect was obtained at 500 μl l-1 of lyophilized NA extract. The increase in CT suggests that the activation of Isc occurs through the insertion of transport sites in the apical membrane. In experiments performed in the absence of Na+transport [apical Na+ was replaced by N-methyl-D-glucamine(NMDG+)], basolateral NA extract did not affect Isc and GT, indicating that Cl- conductance was not influenced. Noise analysis of Isc using 6-chloro-3,5-diaminopyrazine-2-carboxamide(CDPC) showed that NA extract reduced single-channel current(iNa) and decreased channel open probability(Po) but evoked a threefold increase in channel density(NT), which confirms the insertion of Na+channels. The separation of the compounds in the crude extract of NAwas performed by fast protein liquid chromatography (FPLC) on a Superdex 200 gel-filtration column and by reverse-phase high-pressure liquid chromatography(RPHPLC) on an μRPC C2/C18 SC2.1/10 column connected to a SMART system. Analysis of the purified active fraction by mass spectrometry demonstrated the presence of adenosine as the single organic compound in the extract that had a stimulatory effect on Na+ transport. In a separate series of experiments, we confirmed that 1 μmol l-1 adenosine had similar effects on the parameters of Na+ transport as did the NAextract. The action of adenosine was further identified by experiments in which NA extract was added after adenosine. In these experiments, NA extract did not affect Isc, GT or CT. These results clearly demonstrate an essential role of adenosine in the stimulatory action of NA extract.