Traditional Use, Chemistry and Properties of Nigella Damascena

Nigella damascena (Love in the mist), L., 1753, in a garden, Charente, France. By JLPC via Wikimedia Commons.

The genus Nigella (Ranunculaceae) is distributed throughout the Mediterranean basin. Badalamenti et al. (2022)[1] have published a systematic review on the medicinal and traditional use, chemical composition, toxicology and phytotherapy of Nigella damascena L., also known as “love-in-a-mist” and “devil in a bush”. This beautiful plant is It is native to southern Europe, north Africa and southwest Asia, where it is found on neglected, damp patches of land.

From the abstract (with some slight changes in wording):

Nigella damanscena L. is traditionally used as an ingredient in food, for example, as flavouring agents in bread and cheese, but is also known in folk medicine, used to regulate menstruation; for catarrhal affections and amenorrhea; as a diuretic and sternutatory; as an analgesic, anti-oedematous, and antipyretic; as a disinfectant and vermifuge. This paper reviews the most dated to the latest scientific research on this species, highlighting the single isolated metabolites and exploring their biological activity.

Fifty-seven natural compounds have been isolated and characterised from the seeds, roots, and aerial parts of the plant. Among these constituents, alkaloids, flavonoids, diterpenes, triterpenes, and aromatic compounds are the main constituents. The isolated compounds and the various extracts obtained with solvents of different polarities presented a diverse spectrum of biological activities such as antibacterial, antifungal, antitumour, antioxidant, anti-inflammatory, antipyretic, anti-oedema, and antiviral activities. Various in vitro and in vivo tests have demonstrated the pharmacological potential of β-elemene and the alkaloid damascenin. Unfortunately, the largest number of biological studies on this species and its metabolites have been conducted in vitro. Further investigation is necessary to evaluate the toxicological aspects, mechanisms of action and real therapeutic potential of extracts of N. damascena.

[1] Badalamenti N., Modica A., Bazan G., Marino P., Bruno M.
The ethnobotany, phytochemistry, and biological properties of Nigella damascena – A review. Phytochemistry, Volume 198, 2022,
113165. ISSN 0031-9422. https://doi.org/10.1016/j.phytochem.2022.113165.

Phytotherapy for Polycystic Ovary Syndrome

Flax (Linum usitatissimum L.). Public domain photo from Pikist.com.

Azin and Khazali (2021) of Shahid Beheshti University, Tehran, Iran, carried out a literature review of studies concerning the potential role of herbs in the treatment of polycystic ovary syndrome (PCOS), a frequently encountered female complaint.

The 31 studies reviewed collectively covered 25 different herbs, two Traditional Chinese Medicine (TCM) and one Ayurvedic formulae, and four isolates from herbs (berberine, curcumin, soy isoflavone and quercetin).

Of the 25 herbs in the studies, 9 are native to the area of interest of this blog, the Mediterranean and Near East: aloe vera (Aloe
barbadensis
), anise (Pimpinella anisum), fennel (Foeniculum
vulgare
), fenugreek (Trigonella foenum-graecum), flax seed (Linum usitatissimum), hazelnut (Corylus avellana), liquorice (Glycyrrhiza glabra), nettle and pomegranate (Punica granatum).

Of the studies done with these herbs, three were done with human subjects, the other with animal models. Two were done with women with PCOS. Some of the studies showed clinical benefits for PCOS, others showed improved hormone profiles consistent with better potential PCOS outcomes, others still improved secondary complications of PCOS such as metabolic syndrome.

The table below summarises in very basic form some data from the review.

HerbClinical benefits for PCOSImproved hormone profileImproved complications of PCOSHuman/
Animal
Aloe vera**A
Anise**A
Fennel*A
Fenugreek**H
Flax seed**H
Hazlenut**A
Liquorice**A, H
Nettle*A
Pomegranate**A
Citation:

Azin F. & Khazali H. (2021). Phytotherapy of polycystic ovary syndrome: A review. International Journal of Reproductive BioMedicine Volume 20, Issue no. 1, https://doi.org/10.18502/ijrm.v20i1.10404

Antidiabetic Herbs: A Review

Fenugreek flower (Trigonella foenum-graecum – L.). One of the plants discussed in this review, for which there is scientific evidence indicating antidiabetic effects. Public domain photo from Pxfuel.com.

This open access 2018 review by Paolo Governa and co-workers from the University of Siena and the Italian Society of Phytotherapy provides an overview of the use of medicinal plants in the management of diabetes, with particular regard to evidence of clinical effectiveness of medicinal plants in controlling diabetes-related symptoms.

The authors emphasise the following species enlisted in WHO monographs with indication of use for diabetes:

  • Holy basil, Ocimum tenuiflorum L., leaves.
  • Fenugreek, Trigonella foenum-graecum L., seeds.
  • Onion, Allium cepa L., bulb.
  • Neem, Azadirachta indica A. Juss., leaves.
  • Bitter melon, Momordica charantia L., fruit.
  • Korean ginseng, Panax ginseng C.A. Meyer, roots.
  • American ginseng, Panax quinquefolius L., roots.
  • Rehmannia glutinosa (Gaertn.) DC., roots.

Many of these are used of diabetes in traditional medical systems or described in pharmacopoeias for this use. The authors consider that for the first two, holy basil and fenugreek, their use in diabetes is supported by clinical data.

The authors also discuss some other species which are attracting the interest of the scientific community for their promise in treating diabetes.

The authors comment that there is a crucial need for stronger evidence-based data.

Citation

Governa P, Baini G, Borgonetti V, Cettolin G, Giachetti D, Magnano AR, Miraldi E, Biagi M. Phytotherapy in the Management of Diabetes: A Review. Molecules. 2018; 23(1):105. https://doi.org/10.3390/molecules23010105

Seasonal Variations in Chemical Constituents of Some European Herbs

Thymus vulgaris L. in Torà (Segarra, Catalunya, Spain), 490 m altitude. Photo by Isidre blanc, from Wikipedia. Reproduced under Creative Commons CC BY-SA 4.0 licence.

This interesting paper presents an overview of the existing literature published since the year 2000, seeks to identify some repeatedly found seasonal trends and discusses some possible explanations for these trends.

Link to full text of article

Li, Y., Zidorn, C. Seasonal variations of natural products in European herbs. Phytochem Rev (2022). https://doi.org/10.1007/s11101-021-09797-7

Coriander: Traditional Uses, Phytochemistry, Cardiovascular Benefits

Coriandrum sativum L.: Image from Wikimedia Commons. Public domain. Original book source: Prof. Dr. Otto Wilhelm Thomé Flora von Deutschland, Österreich und der Schweiz 1885, Gera, Germany.

Simple Summary

The following is a simple summary of this recent review paper:

Mahleyuddin, N.N.; Moshawih, S.; Ming, L.C.; Zulkifly, H.H.; Kifli, N.; Loy, M.J.; Sarker, M.M.R.; Al-Worafi, Y.M.; Goh, B.H.; Thuraisingam, S.; et al. Coriandrum sativum L.: A Review on Ethnopharmacology, Phytochemistry, and Cardiovascular Benefits. Molecules 2022, 27, 209. https://doi.org/10.3390/molecules27010209.

1. Traditional Uses in Various Old-World Regions

Fruits (seeds)

  • Rheumatoid arthritis, inflammation, and joint pain.
  • Some liver diseases (roasted seeds).
  • Dyspeptic complaints, as a digestive.
  • Loss of appetite, as an appetiser.
  • Convulsions.
  • Anxiety, insomnia.
  • As a diuretic.
  • “Melancholia”.
  • To lower blood glucose levels.
  • Influenza.
  • Bad breath.
  • Bad odour from genitalia.

Leaves

  • Mouth ulcer.
  • Eye redness.
  • “Melancholia”.
  • Digestive complaints, poor digestion.
  • To lower blood glucose levels.

Aerial parts

  • Viral infection.
  • Neurasthenia.

Whole plant

  • Measles.
  • Diabetes.
  • Aerophagy.
  • Gastroenteritis.
  • As a diaphoretic.
  • As a diuretic.
  • As a carminative.
  • As a stimulant.

Essential oil

  • Aa an aphrodisiac.
  • As an analgesic.
  • As an antimicrobial, mouth infections.
  • As a digestive stimulant.
  • Gastric ulcers.

Unspecified part(s)

  • As a diuretic, some renal diseases.
  • Anxiety; as a sedative and muscle relaxant.

2. Main Phytochemical Constituents

Fruits (seeds)

  • Carotenoids including β-carotene.
  • Tocols: α-, β-, γ- δ- tocopherols, and α-, γ-tocotrienols.
  • Fatty acids: Petroselinic linoleic, palmitic and oleic acids.
  • Sterols: Stigmasterol, β-sitosterol, δ-stigmasterol.
  • Volatile constituents: Linalool, camphor, geraniol.

Aerial parts

  • Carotenoids including β-carotene.
  • Phenolic acids: Ferulic, gallic and caffeic acids.
  • Benzoic acid derivative: Salicylic acid.
  • Coumarins: Esculetin, esculin, scopoletin, 4-hydroxycoumarin, umbelliferone, dicoumarin.
  • Flavonoids: hyperoside, rutin, hesperidin, vicenin, diosmin, luteolin, apigenin, orientine, dihydroquercetin, catechin, arbutin.

Essential oil

  • Linalool.
  • γ-terpenine.
  • α-pinene.

3. Physiological Effects of Phytochemicals from C. sativum

Flavonoids: A flavonoid-rich fraction was found to have hypotensive activity.

Quercetin (a flavonoid): A quercetin-rich aqueous ethanolic extract inhibits α-amylase, α-glucosidase and lipase, and thus potentially has antidiabetic and anti-obesity effects.

Polyphenols: A polyphenol-rich extract inhibits angiotensin-converting enzyme thus potentially has a antihypertensive effect.

Isocoumarins: Isocoumarin aglycones and (to a lesser degree) isocoumarin glycosides (cilantroside A and B) have been found to have neurotrophic / neuroprotective effects by stimulation of nerve growth factor. The aglycones of isocoumarins also showed anti-inflammatory effects.

Phenolic glycosides: The phenolic glycosides daphnin and benzyl-O-β-d-glucoside have also been found to stimulate nerve growth factor.

Sterols: Plant sterols have hypocholesterolaemic effects.

Essential oil: Prominent activities against diabetes, microbial infections, and inhibitory to acetylcholinterase.

Other: A linalool, ascorbyl palmitate and petroselinic acid-rich petroleum ether extract of coriander seeds reduces oxidative stress, is hypolipidaemic, hypoglycaemic, and preventative against diabetic nephropathy.

4. Cardiovascular Benefits of C. sativum

A systematic review was carried out of studies investigating the potential cardiovascular benefits of C. sativum.

Studies have demonstrated the cardioprotective benefits of C. sativum. These include its effect as an antioxidant, antihypertensive, anti-atherogenic, antiarrhythmic, as well as the improvement of other factors that may lead to cardiovascular disease (CVD), such as altered lipid profile, hyperglycaemia and cardiac biomarkers or enzymes.

Most of the studies included in the review were in vivo studies carried out on laboratory animals. Only two were human studies. These latter demonstrated hypolipidaemic, hypocholesterolaemic, hypotensive and antioxidant effects of coriander seed powder. As to plant parts, the majority of the studies included investigated the effects of the seeds. The two studies on the leaves showed hypolipidaemic, hypotensive, normoglycaemic and antioxidant effects.

The authors comment that more in vitro studies are needed to elucidate mechanisms of action.