Journal of Medicinal Plants
Volume:22 Issue: 85, Mar 2023

Antihypertensive plants are one of the means of hypertension control.

To examine the clinical antihypertensive efficacy and safety of the plants found in Iran.

PUBMED, MEDLINE, SCOPUS, EMBASE, SCIENCEDIRECT, PROQUEST, OVID, EBSCO, GOOGLE, and GOOGLE SCHOLAR were searched. The PRISMA guideline was observed. The search terms were Iran, Iranian, plant, herb, antihypertensive, hypertension and randomized controlled trial (RCT). English-language articles published until the end of 2022 were included. In-vitro and animal studies, editorials, and reviews were excluded. The methodological quality of the RCTs was evaluated using the JADAD scale.

Two hundred and eight studies were found. Only 74 of them were eligible. For Berberis vulgaris (5 studies), Nigella sativa (10 studies), Allium sativum (12 studies), Hibiscus sabdariffa (11 studies), Beta vulgaris L (15 studies), Solanum lycopersicum (5 studies), Cinnamomum verum (9 studies), Rhus coriaria (1 study), Phyllanthus emblica (1 study), Olea europaea (4 studies), and Vaccinium arctostaphylos (3 studies) were found. Most RCTs had high methodological quality and reported efficacy and no side effects.

While most trials demonstrate antihypertensive efficacy and safety, there are more evidence regarding Hibiscus sabdariffa, Olea europaea, Vaccinium arctostaphylos and Allium sativum versus the other plants.

Scrophularia oblongifolia belongs to the Scrophulariaceae family, commonly known as the water figwort in Iran. It has been known as a traditional medicinal plant in Iran.

This study was designed to investigate the phytochemicals and antimicrobial activity of ethyl acetate, methanol, MeOH: H2O (50:50 v/v), and n-hexane extract of Scrophularia oblongifolia aerial parts, growing in the Kangavar region in the Kermanshah province of Iran.

Compounds of ethyl acetate extract were isolated by chromatographic techniques (HPLC-PDA-MS/MS-Q-TOF) and their structures were elucidated by spectral methods (1D and 2D NMR). The antifungal and antibacterial activities of some new compounds and ethyl acetate, methanol, and n-hexane extract were evaluated.

Two new polyphenol iridoid glycosides with phenylpropanoid moiety namely scrophuloside A5 and scrophuloside A6; two known phenylpropanoid glycosides namely scrophuloside A3 and scrophuloside A4, and two known iridoid glycosides namely aucubin and harpagoside were isolated from S. oblongifolia. Pure compounds showed high antifungal activities with MIC values ranging from 0.35 to 0.74 µg/ml against C. albicans and high antibacterial activities with MIC values ranging from 0.70 to 1.48 µg/ml against G. vajinalis. n-Hexan extract showed moderate antibacterial and antifungal activity, while methanol and methanol:H2O (50:50 v/v) extract showed no antimicrobial activities.

Based on these findings, compounds isolated from S. oblongifolia have demonstrated potential antibacterial and antifungal activities.

The genus Mentha consists of several important medicinal plant species whose active ingredients are used for treating liver and prostate cancers, acute respiratory infection and allergic digestive problems, neuralgia, and migraines.

This study aimed to investigate the effects of methyl jasmonate (MeJA) and salicylic acid (SA) in the field condition on the chemical composition of the essential oil of two in vitro propagated species of Mentha genus including Mentha x piperita and Mentha pulegium.

M. piperita and M. pulegium species were propagated through the tissue culture method and the in vitro propagated plants were transferred to the farm after acclimatization. Then, the plants were treated with foliar application of MeJA and SA at four concentrations (0, 2, 4, and 6 mM) at three developmental stages. Chemical composition of the essential oils of samples were determined using a GC-MS analysis.

Both elicitors increased the level of menthol production in peppermint (M. x piperita), but in pennyroyal (M. pulegium), the level of pulegone production as the main secondary metabolite was decreased. Among different metabolites detected in the essential oil of peppermint, myrcene, octanal, γ-terpinene, ocimene, carvacrol, iso-menthol, neo-menthol, and oxygenated sesquiterpenes were the constituents with the lowest amounts under MeJA and SA treatment.

The application of MeJA and SA significantly impacted on the quality and quantity of secondary metabolites of these species. The desired performance of valuable secondary metabolites can be achieved by determining the type and dosage of elicitors.

Thymus fallax Fisch. & C.A.Mey. is one of the medicinal plants of the Lamiaceae family, which aerial part contains valuable phytochemical compounds such as thymol and carvacrol.

This study was performed for assessing the essential oil diversity of different populations of Thymus fallax in its habitats.

The populations of Thymus fallax were collected from its natural habitats in Alborz, Tehran, Zanjan, Mazandaran, and North Khorasan provinces. Their essential oils were extracted by hydro-distillation method and the compounds were identified using GC and GC-MS.

The result indicated that the essential oil content of populations was on average 1.71 %, the highest percentage of which was observed in the population of Migoun(2.58 %), Chelcheshmeh (2.35 %), and Ghormehdareh (2.25 %), and the lowest was obtained in Dizin (1.05 %) and Ira (1.15 %). Overall, 30 essential oil compounds were identified, comprising 95 % of the total essential oil, of which carvacrol, thymol, p-cymene, and geraniol were the major constituents, accounting for 75 % of the essential oil. Five groups of thyme population were identified using cluster analysis, including the first group with high content of carvacrol, the second group with high content of geraniol, the third group with high content of thymol and carvacrol, the fourth group with high content of thymol, and the fifth group with high content of thymol, carvacrol and geraniol.

The high amounts of essential oil, carvacrol and thymol in some populations were valuable results that can be considered in future and breeding studies.

Tea (Camellia sinensis), belongs to the family Theaceae, is a well-known perennial and evergreen plant that is processed and widely used as a daily drink across the world.

The present study was aimed to explore aromatic composition, catechins content, and metal elements (MEs) profiling of forty-three black tea samples collected across Iran.

Black tea samples were prepared from the Iranian Tea Research Institute. MEs content of the plant dried samples was measured by atomic absorption spectrometer. Aromatic composition and catechins content of the studied samples were analyzed by GC-FID, GC-MS and HPLC, respectively.

Hexanal (0.3-27.6 %), cis-linalool oxide (0.1-44.7 %), trans-linalool oxide (0.2-48.3 %), linalool (0.2-39.2 %), benzyl alcohol (0.2-38.9 %), phenylethanol (0.1-37.9 %), and (-)-Myrtenol (4.4-26.8 %) were the major volatile oil compounds of the studied samples. The highest content of hexanal, cis-linalool oxide, trans-linalool oxide, linalool, benzyl alcohol, phenylethanol and (-)-Myrtenol was measured in IR5 (Zarin), IR13 (Leil 1), IR23 (Shariat), IR31 (Roozmehr 1), IR34 (Noshiran), IR36 (Roozmehr 3) and IR18 (Amard 2), respectively. Catechin content was ranged from 0.589 ± 0.0285 in IR32 (Roozmehr 2) to 0.65 ± 0.0088 in IR29 (Aramgol 1). The level of the copper, Iron and lead were generally within the safe limitation mentioned in the world.

Sample of Roozmehr was characterized with high aromatic compounds, catechins content, and low level of MEs. This information can be interestingly considered by food industrials to process black tea products.

Ferula assa-foetida is an endemic medicinal plant of Iran. Its oleo-gum resin or assafoetida gum (AG) is an important herbal product whose standardization is important to ensure effectiveness and safety.

Due to the lack of accurate and complete data about Iranian AG, the objective of this study is to extend the available knowledge by reporting some physicochemical and phytochemical properties of an Iranian AG sample.

Organoleptic properties were determined by sensory evaluation. Total ash, acid-insoluble ash, dry residue as well as total phenolic and flavonoid content were measured by accepted methods to determine some physicochemical and phytochemical properties of AG. Analysis of its essential oil by GC/MS as well as microbial load assessment were performed.

The AG was a yellowish brown mass with a sulfur-like pungent odor similar to garlic, with total ash and acid-insoluble ash of 2.83 % and 2.06 %, respectively, and a dry residue of 3.43 %. Total phenol content was 4.15 ± 0.26 mg gallic acid equivalent/g in dry AG. (E)-1-Propenyl sec-butyl disulphide, (Z)-1-propenyl sec-butyl disulphide, and 2,4-thiazelidinedione were the major essential oil component of this oleo-gum resin. Microbial load was in acceptable range according to Pharmacopeia.

The current findings provide data on some of the physicochemical and phytochemical properties of Iranian AG which is applicable for completing current knowledge. Although more information is needed for establishing Iranian AG standardization criteria, which will be obtained from more extensive researches.

The perennial fennel plant is one of the most important and widely used medicinal plants of the Apiaceae family, which is mainly cultivated for the purpose of using the essential oil obtained from it in various pharmaceutical, food, cosmetic and health industries.

To investigate callogenesis and secondary metabolites production from calli, 13 populations of Iranian fennel as well as two populations from Germany and two populations from Turkey were evaluated by GC-MS.

Five types of explants (leaf, hypocotyl, epicotyl, cotyledon, and root segments) were cultured in MS medium supplemented with combination of 2,4-D + Kinetin (1:1), and also NAA + BA (0.5:1).

Among five explants used in this study, only hypocotyl explant had appropriate response to the callogenesis. According to the GC-MS analysis, the highest trans-anethole content (67.23 %) was produced in the callus of Turkish population (TUR1) under NAA + BA treatment (1:1). Callus extracts of other Turkish population (TUR2) contained considerable amounts of limonene (67.70 %) under 2,4-D + Kinetin treatment (0.5:1).

Callus induction with different plant regulators can have a significant contribution to the production of secondary metabolites, so callus that produce more secondary metabolites can be cultured in suspension or cell culture bioreactor systems. Based on the results of this research, Turkish fennel populations had the capacity to produce significant amounts of main secondary metabolites.

The genus Bauhinia consists of about 300 species and is widely distributed in most tropical countries of the world.

The antioxidant, antibacterial, antidiabetic, and quantitative analysis of stem, leaf, and seed extracts of B. vahlii (the synonym name of Phanera vahlii) were investigated.

The antioxidant activity of the crude extracts and fractions was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging assay. The antidiabetic activity was investigated by α-amylase inhibition assay. The toxicity of plant extracts was assessed by brine shrimp lethality assay (BSLA) using Artemia salina as a biological test organism.

The aqueous fraction of the leaf showed a high total phenolic content of 168.47 ± 1.94 mg GAE/g. The total flavonoid content was found maximum in an aqueous fraction of leaf with 158.51 ± 2.99 mg QE/g. The stem extract showed potent antioxidant activity with IC50 1.91 ± 0.33 µg/ml as compared to the standard quercetin IC50 3.46 ± 0.40 µg/ml. The DCM (Dichloromethane) fraction of the leaf exhibited noteworthy α-amylase inhibition properties with IC50 112.70 ± 2.0 µg/ml as compared to the standard acarbose of 9.34 ± 2.0 µg/ml. The antimicrobial results showed that the methanolic extract of stem and seed exhibited the zone of inhibition against Staphylococcus aureus, Bacillus subtilis, and Klebsiella pneumoniae but failed against E. coli. The methanol and aqueous extract of the leaf showed toxicity against brine shrimp nauplii with LC50 257.63 µg/ml and 100 µg/ml, respectively.

This study showed Bauhinia vahlii is rich in flavonoid and phenolic content and the plant may be a rich source of natural antioxidants and antidiabetic agents that could be isolated as the drug candidate.