Chemical Constituents of Stinging Nettle (Urtica dioica L.): A Comprehensive Review on Phenolic and Polyphenolic Compounds and Their Bioactivity.

Polyphenolic compounds are of great interest in today's science. Naturally, they occur in plants and other sources in many different forms. Their wide range of biological activity has attracted the attention of the scientific community. One of the sources of phenolic compounds is stinging nettle (Urtica dioica L.), a common plant in almost all parts of the world. A long tradition of utilization and an interesting chemical profile make this plant a fascinating and extensive object of study. The chemical profile also allows this plant to be used as a food and a pigment source in the food, pharmaceutical, and cosmetic industries. Previously conducted studies found phenolic acids and polyphenolic compounds in root, stalk, and stinging nettle leaves. Different extraction techniques were usually used to isolate them from the leaves. Obtained extracts were used to investigate biological activity further or formulate different functional food products. This study aimed to collect all available knowledge about this plant, its chemical composition, and biological activity and to summarize this knowledge with particular attention to polyphenolic compounds and the activity and mechanisms of their actions.

The role of stinging nettle (Urtica dioica L.) in the management of rotenone-induced Parkinson's disease in rats.

Parkinson's disease (PD) is one of the most common neurodegenerative conditions. Alpha-synuclein deposition, Lewy bodies (LBs) formation, disruption of the autophagic machinery, apoptosis of substantia nigra dopaminergic neurons, oxidative stress, and neuroinflammation are all pathologic hallmarks of PD. The leaves of the stinging Nettle (Urtica dioica L.) have a long history as an herbal cure with antioxidant, anti-inflammatory, anti-cancer, immunomodulatory, and neuroprotective properties. The current study aims for the first time to investigate the role of Nettle supplementation on Rotenone-induced PD. Rats were divided into five groups; a Saline control, Nettle control (100 mg/kg/day), Rotenone control (2 mg/kg/day), Rotenone + Nettle (50 mg /kg/day), and Rotenone + Nettle (100 mg/kg). After four weeks, the rats were examined for behavioral tests. The midbrains were investigated for histopathological alteration and immunohistochemical reaction for Tyrosine hydroxylase in the dopaminergic neurons, α-synuclein for Lewy bodies, caspase 3 for apoptotic neurons, LC3 and P62 for autophagic activity. Midbrain homogenates were examined for oxidative stress markers. mRNA expression of TNFα and Il6; inflammatory markers, Bcl-2, BAX and Caspase 3; apoptosis markers, were detected in midbrains. The results showed that Nettle caused recovery of midbrain dopaminergic neurons, by inhibiting apoptosis, inflammation, and oxidative stress and by restoring the autophagic machinery with clearance of α-synuclein deposits. We can conclude that Nettle is a potentially effective adjuvant in the treatment of Parkinson's disease.

Sono-Microwave Assisted Chlorine free and Ionic Liquid (SMACIL) extraction of cellulose from Urtica dioica: A benign to green approach.

The extraction of cellulose using eco-friendly solvents has been gaining significant attention for a couple of decades. This study investigated the impact of benign and green solvents on the extraction, thermal stability, mechanical properties, and crystallinity of cellulose extracted from Urtica dioica (Stinging nettle) using a Sono-Microwave Assisted Chlorine free and Ionic Liquid (SMACIL) extraction technique. In this regard, the stalks were undergone through pre chemical treatment before starting bleaching them with hydrogen peroxide (HPO) and 1-butyl-3-methylimidazolium acetate (BMIM-Ac) having different mole ratios (5, 7.5, and 10) to expose cellulose. The Urtica dioica cellulose (UDC) was characterized using FTIR, tensile testing, FESEM, XRD, and TGA. The fibrillation and lumen can be seen in SEM images that confirm the extraction of cellulose. The results showed that the BMIM-Ac-10 gives the maximum cellulose yield (88 %) than other compositions. Moreover, the cellulose extracted using BMIM-Ac-10 has high mechanical strength which makes it a potential constituent for various applications in the field of materials science. These results have significant implications for the development of sustainable and efficient processes for the extraction of cellulose.

Protective effects of Urtica dioica on the cerebral cortex damage induced by Potassium bromate in adult male albino rats.

Potassium bromate is used in cheese production, beer making and is also used in pharmaceutical and cosmetic. It is a proven carcinogen as it is a strong oxidizing agent that generates free radicals during xenobiotic metabolism. Urtica dioica (Ud) (from the plants' family of Urticaceae) is a plant that has long been used as a medicinal plant in many parts of the world. It has been shown to have anti-inflammatory, antioxidant and immunosuppressive properties. So, this study aimed to clarify the effect of Potassium bromate on the histological structure of cerebral cortex of adult male albino rats, evaluate the possible protective role of Urtica dioica. Thirty adult healthy male albino rats were divided into three groups; group I (Control group), group II (KBrO3 treated group). Group III (KBrO3 and Urtica dioica treated group).At the end of the experiment, rats in all groups were anesthetized and specimens were processed for light and electron microscope. Morphometric and statistical analyses were also performed. Nerve cells of the treated group showed irregular contours, dark nuclei, irregular nuclear envelopes, dilated RER cisternae, and mitochondria with ruptured cristae. Vacuolated neuropil was also observed. Immunohistochemically, stained sections for GFAP showed strong positive reaction in the processes of astrocytes. Recovery group showed revealed nearly the same as the histological picture as the control group. In conclusion, potassium bromate induces degenerative effects on neurons of cerebral cortex and urtica dioica provide an important neuroprotective effects against these damaging impacts through their antioxidant properties.

Determination of phytochemical content by LC-MS/MS, investigation of antioxidant capacity, and enzyme inhibition effects of nettle (Urtica dioica).

OBJECTIVE: Urtica dioica L. Subsp. dioica is an annual or perennial herbaceous plant belonging to the Urticaceae family that has an important place in ethnobotany. This study aimed to investigate the phytochemical content and the inhibition effect on acetylcholinesterase (AChE), which interact with beta-amyloid to promote the deposition of amyloid plaques and paraoxonase (PON1). This plays a role in the regulation of HDL and LDL and an antiatherogenic, and antioxidant capacity of Urtica dioica. MATERIALS AND METHODS: Phytochemical content was determined by the liquid chromatography/mass spectrometry (LC-MS/MS), and to assess the enzyme inhibition and antioxidant capacity the spectrophotometer technique was used. The antioxidant capacity of U. dioica extracts (methanol, hexane, and water) was determined by applying 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+), 2,2-diphenyl-1-picrylhydrazyl (DPPH•+), ferric reducing antioxidant power (FRAP), and cupric ion reducing antioxidant capacity (CUPRAC) methods. RESULTS: The methanol extract of the U. dioica exhibited significant inhibition on the AChE (IC50= 0.098 ± 0.011 mg/mL). However, methanol and water extracts of the U. dioica did not exhibit the inhibition effect on PON1. The highest activity for ABTS•+ was in the hexane extract (55.97%), and for DPPH•+ was in the methanol extract (62.42%). Compared to other solvents (hexane and water), the methanol extract of the U. dioica showed the highest activity for FRAP and CUPRAC methods. Results (as absorbance) were 0.302 for CUPRAC and 0.147 for FRAP in the methanol extract of the U. dioica. The acetohydroxamic acid, gallic acid, caffeic acid, ellagic acid, p-hydroxybenzoic acid, and quercetin were qualified and quantified in LC-MS/MS analyses of Urtica dioica extract. CONCLUSIONS: U. dioica, which has antioxidant, anti-atherosclerotic and neuroprotective effects, has a natural medicine potential if compared to synthetic drugs used in Alzheimer's patients.

Recovery of Polyphenolic Compounds and Vitamins from the Stinging Nettle Leaves: Thermal and Behavior and Biological Activity of Obtained Extracts.

Stinging nettle (SN) is an extraordinary plant from the Urticaceae botanical family. It is well-known and widely used in food and folk medicine to treat different disorders and diseases. This article aimed to study the chemical composition of SN leaves extracts, i.e., polyphenolic compounds and vitamins B and C, because many studies ascribed high biological potency to these compounds and their significance in the human diet. Besides the chemical profile, the thermal properties of the extracts were studied. The results confirmed presence of many polyphenolic compounds and vitamins B and C. It also showed that the chemical profile closely correlated with the applied extraction technique. The thermal analysis showed that analyzed samples were thermally stable up to about 160 °C. Thermal degradation of samples UAE, MAE, and MAC took place in four steps, and sample SE in three steps. Altogether, results confirmed the presence of health-beneficial compounds in stinging nettle leaves and indicated the possible application of its extract in pharmaceutical and food industries as both a medicinal and food additive.

Intraspecific Variability of Stinging Nettle (Urtica dioica L.).

The purpose of the work was to determine the intraspecific variability of the stinging nettle, in respect of the mass of leaves and their chemical composition, including the content of phenolic compounds and assimilative pigments. The objects of the study were 10 populations of nettle, originating from the eastern and southern part of Poland. The results obtained indicate a high level of variability between and within the populations investigated but not strictly related to their geographical locations. The mass of the leaves ranged from 0.19 to 0.28 kg dry weight (DW)/plant (Coefficient of variation (CV) = 16.33%). Using HPLC-DAD, four phenolic acids were detected, i.e., caffeoylmalic (570.97-1367.40 mg/100 g DW), chlorogenic (352.79-1070.83 mg/100 g DW), neochlorogenic (114.56-284.77 mg/100 g DW) and cichoric (58.31-189.52 mg/100 g DW) acids, with the last one differentiating populations to the highest degree (CV = 48.83%). All of the analyzed populations met the requirements of the European Pharmacopoeia (Ph Eur 10th) concerning the minimum content of caffeoylmalic and chlorogenic acids in nettle leaves (not less than 0.3%). Within the flavonoid fraction, two compounds were identified, namely rutoside (917.05-1937.43 mg/100 g DW, CV = 21.32%) and hyperoside (42.01-289.45 mg/100 g DW; CV = 55.26%). The level of chlorophyll a ranged from 3.82 to 4.49 mg/g DW, chlorophyll b from 1.59 to 2.19 mg/g DW, while the content of carotenoids varied from 2.34 to 2.60 mg/100 g DW. Given all the traits investigated, the level of a population's polymorphism (CV) was visibly higher within a population than between populations. Population no. 4 was distinguished by the highest mass of leaves, and the highest content of rutoside, while population no. 2 was distinguished by the highest content of hyperoside, caffeoylmalic and chlorogenic acid.

Sterols and pentacyclic triterpenoids from nettle root: content and composition as affected by pressurized liquid extraction.

BACKGROUND: Nettle is a medicinal plant rich in bioactive molecules. The composition of nettle leaves and stems has been extensively studied, whereas the root has been insufficiently investigated. Therefore, the present study aimed to optimize the parameters of advanced extraction technique, pressurized liquid extraction (PLE), for the lipid fraction of nettle root rich in triterpenoid derivatives and to compare the efficiency of isolation under optimal conditions with conventional Soxhlet extraction (SE). RESULTS: The PLE yields ranged from 0.39-1.63%, whereas the total content of triterpenoid derivatives ranged from 43.50-78.26 mg 100 g-1 , with nine sterols and three pentacyclic triterpenoids identified and quantified within a total range of 42.81-76.57 mg 100 g-1 and 0.69-1.68 mg 100 g-1 dried root, respectively. The most abundant sterol and pentacyclic triterpenoid were ß-sitosterol and ß-amyrin acetate, with mean values of 50.21 mg 100 g-1 and 0.56 mg 100 g-1 dried root. CONCLUSION: The optimal PLE conditions were 150 °C/5 min/four cycles and showed significantly better performance compared to SE (68 °C, 8 h), establishing an excellent technique for the isolation of the nettle root lipid fraction. Also, triterpenoid derivatives from nettle could be used as functional ingredients for the development of new foods and dietary supplements. © 2022 Society of Chemical Industry.

Hydroethanolic Extract of Urtica dioica L. (Stinging Nettle) Leaves as Disaccharidase Inhibitor and Glucose Transport in Caco-2 Hinderer.

Herbal treatment for diabetes mellitus is widely used. The pharmacological activity is thought to be due to the phenolic compounds found in the plant leaves. The present study aims to investigate the phytochemical composition of Urtica dioica (UD) hydroethanolic extract and to screen its antidiabetic activity by disaccharidase hindering and glucose transport in Caco-2 cells. The results have shown that a total of 13 phenolic compounds in this work, viz. caffeic and coumaric acid esters (1, 2, 4-7, 10), ferulic derivative (3), and flavonoid glycosides (8, 9, 11-13), were identified using HPLC-DAD-ESI/MS2. The most abundant phenolic compounds were 8 (rutin) followed by 6 (caffeoylquinic acid III). Less predominant compounds were 4 (caffeoylquinic acid II) and 11 (kaempferol-O-rutinoside). The UD hydroethanolic extract showed 56%, 45%, and 28% (1.0 mg/mL) inhibition level for maltase, sucrase, and lactase, respectively. On the other hand, glucose transport was 1.48 times less at 1.0 mg/mL UD extract compared with the control containing no UD extract. The results confirmed that U. dioica is a potential antidiabetic herb having both anti-disaccharidase and glucose transport inhibitory properties, which explained the use of UD in traditional medicine.

Urtica dioica and Dodonaea viscosa leaf extracts as eco-friendly bioagents against Alternaria alternata isolate TAA-05 from tomato plant.

One of the tomato's acutely devastating diseases is Alternaria leaf spot, lowering worldwide tomato production. In this study, one fungal isolate was isolated from tomatoes and was assigned to Alternaria alternata TAA-05 upon morphological and molecular analysis of the ITS region and 18SrRNA, endoPG, Alt a1, and gapdh genes. Also, Urtica dioica and Dodonaea viscosa methanol leaf extracts (MLEs) were utilized as antifungal agents in vitro and compared to Ridomil, a reference chemical fungicide. The in vitro antifungal activity results revealed that Ridomil (2000 µg/mL) showed the highest fungal growth inhibition (FGI) against A. alternata (96.29%). Moderate activity was found against A. alternata by D. viscosa and U. dioica MLEs (2000 µg/mL), with an FGI value of 56.67 and 54.81%, respectively. The abundance of flavonoid and phenolic components were identified by HPLC analysis in the two plant extracts. The flavonoid compounds, including hesperidin, quercetin, and rutin were identified using HPLC in D. viscosa MLE with concentrations of 11.56, 10.04, and 5.14 µg/mL of extract and in U. dioica MLE with concentrations of 12.45, 9.21, and 5.23 µg/mL, respectively. α-Tocopherol and syringic acid, were also identified in D. viscosa MLE with concentrations of 26.13 and 13.69 µg/mL, and in U. dioica MLE, with values of 21.12 and 18.33 µg/mL, respectively. Finally, the bioactivity of plant extracts suggests that they play a crucial role as antifungal agents against A. alternata. Some phenolic chemicals, including coumaric acid, caffeic acid, ferulic acid, and α-tocopherol, have shown that they may be utilized as environmentally friendly fungicidal compounds.

Short-term Variability of Macro- and Trace Elements in Elymus Repens L. and Urtica Dioica L.

BACKGROUND: The main aim of the research was to study short-term changes in the concentrations of elements in two widely distributed plant species, couch grass and nettle and in the rhizosphere soil of the plants. METHODS: The sampling of plants and soil was carried out on three dates: 3, 10, and 25 May 2021. On each day of sampling, the plants and soil were collected three times: at 9:00, 14:00, and 19:00. The ICP-OES and ICP-MS analytical techniques were used for determination of elements in the plant and soil samples. The Raman spectroscopy was applied to study variations in the organic compounds. RESULTS: The concentrations of both macro-nutrients and trace elements in plants varied greatly over daytime on all dates of sampling. The differences between concentrations of many elements in the plants collected at different times during a day were statistically significant. There were also statistically significant differences between concentrations of some elements (Na, Mg, P, K, Fe, Ba) in the plants collected on different dates. The relative intensity of diffuse luminescence of the rhizosphere soil of couch grass and nettle was different during daytime and also differed between the soils taken from roots of the two plant species, especially in the beginning of May. CONCLUSIONS: The experimental data indicates that the daily variations of the element concentrations in plants might be a result of multiple effects of various factors. The differences in the daily element variations in the couch grass and nettle growing in the same site and collected simultaneously might be due to the fact that these plants belong to different clades. The diurnal fluctuations (that also include regular changes in the element concentrations in plants) can be different for monocotyledons (couch grass) and dicotyledons (nettle). New experimental findings on short-term variations in the concentrations of macro-nutrients and trace elements can help to gain a new insight into accumulation of the elements in different plant species and also be useful in agricultural practice.

[Chemical constituents from Urtica dioica fruits].

The chemical constituents in Urtica dioica fruits were investigated by silica gel chromatography, preparative HPLC, NMR, and HR-MS for the first time. As a result, 21 compounds were isolated from the fruits of U. dioica and identified 7R,8S,8'R-olivil(1), oleic acid(2), α-linoleic acid(3), palmic acid(4), methyl palmitate(5), α-linolenic acid(6), α-linolenic acid methyl ester(7), 5-O-caffeoyl-shikimic acid(8), vanillic acid(9), p-coumaric acid(10), 5-O-p-coumaroylshikimic acid(11), cinnamic acid(12), quinic acid(13), shikimic acid(14), ethyl caffeate(15), coniferyl ferulate(16), ferulic acid(17), caffeic acid(18), chlorogenic acid(19), pinoresinol(20), and quercetin(21). Compound 1 was a new compound and compounds 2-16 were isolated from U. dioica for the first time.

Stinging Nettle (Urtica dioica L.): Nutritional Composition, Bioactive Compounds, and Food Functional Properties.

Stinging nettle (Urtica dioica L., Urticaceae) is commonly found in Asia, Africa, and Europe and has a long history of being used as food and traditional medicine. Recently, this plant is gaining attention as a highly nutritious food, where fresh leaves are dried and used as powder or in other forms. Leaves are rich in many bioactive compounds. This review aims to cover the traditional uses in food and medicine, as well as its nutritional composition, including its bioactive chemical constituents and reported food functional activities. Various bioactive chemical constituents have been isolated from stinging nettle to date, such as flavonoids, phenolic acids, amino acid, carotenoids, and fatty acids. Stinging nettle extracts and its compounds, such as rutin, kaempferol, and vitamin A, are also used for their nutritional properties and as anti-inflammatory and antioxidant agents. Future studies should focus on the proper formulation and stability testing of the functional foods containing stinging nettle and their detailed activities in clinical studies.

Resistance training and Urtica dioica increase neurotrophin levels and improve cognitive function by increasing age in the hippocampus of rats.

INTRODUCTION: Inflammation and oxidative stress are two major factors in accelerating brain aging. Consumption of some traditional herbs with antioxidant and anti-inflammatory properties such as Urtica dioica extract (Ud) and resistance training (RT) may be effective in controlling premature aging and memory impairment. Therefore, we hypothesized that the combined effect of RT and Ud might play an essential role in preventing memory disorders and hippocampal tissue changes caused by increasing age in rats. METHODS: 28 male Wistar rats (24-week) were divided into 4-groups (n = 7): control (C), Ud, RT, and Ud+RT. RT groups were trained for five weeks, and Ud extract in the 0.0166 w/v concentration (50 mg/kg, oral/daily) was administered. We also examined the effects of RT and Ud on the behavioral (memory and learning), histological (the morphological changes in the dentate gyrus), and transcript aspects of hippocampal tissue. RESULTS: Aging led to karyopyknosis in the hippocampal tissue, which was alleviated by RT and Ud supplementation. RT and Ud were accompanied by increased GPx, GSH, GAP-43, and decreased CAP-1 levels in the hippocampus. Moreover, RT and Ud led to increased NGF, BDNF, and GAP-43 levels, decreased MDA, and protection of hippocampal tissue from karyopyknosis, which was associated with cognitive improvement. However, these interventions had no significant effect on the hippocampal levels of IL-1ß, SOD, and CAT. CONCLUSIONS: These findings suggest that increasing age decreases hippocampal NGF, BDNF, and GAP-43 levels and impairs cognition, which may be reversed by regular RT and Ud extract.

Anticancer Effects of Urtica Dioica in Breast Cancer.

OBJECTIVE: The goal of this study is to look into the antiproliferative capabilities of Urtica Dioica (UD) on breast cancer. METHODS: The cytotoxicity of UD extracts against breast cancer cell lines was investigated. Flow cytometry analyses were used to investigate in vitro apoptosis of breast cancer cells using Annexin V labeling. In vivo tests also performed. RESULTS: UD showed cytotoxicity to three cancer cell lines. The number of Annexin-positive cells was higher in UD-treated cell lines than in untreated control cells. When compared to the untreated control group, the rats treated with UD had greater expressions of caspase 3, p53 protein, and TUNEL positive cells. When compared to the control group, Ki-67 expression was reduced in the treatment groups. In vivo tests revealed that, when compared to untreated rats, the mean tumor volume inhibition ratio in the UD group was 38 percent. CONCLUSION: These findings suggest that Urtica Dioica may have antitumoral properties in the treatment of breast cancer.

Exercise and Urtica Dioica extract ameliorate mitochondrial function and the expression of cardiac muscle Nuclear Respiratory Factor 2 and Peroxisome proliferator-activated receptor Gamma Coactivator 1-alpha in STZ-induced diabetic rats.

INTRODUCTION: Diabetes mellitus can affect and disrupt the levels of PGC1α and NRF2 proteins in the mitochondrial biogenesis pathway. Considering the anti-diabetic properties of Urtica Dioica extract and exercise, this study aimed to investigate the beneficial effects of Urtica Dioica extract and endurance activity on PGC1α and NRF2 protein levels in the streptozotocin-induced diabetic rat heart tissue. MATERIALS AND METHODS: 58 male Wistar rats were divided into five groups (N = 12) including: healthy control (HC), diabetes control (DC), diabetes Urtica Dioica (D-UD), diabetes exercise training (DT), and diabetes exercise training Urtica Dioica (DT-UD). Diabetes was induced intraperitoneally by STZ (45 mg/kg) injection. Two weeks after the induction of diabetes, the rats were stimulated to carry out the exercise (moderate intensity/5day/week) and the gavage of UD extract (50 mg/kg/day) was administered to the rats for six weeks. In this study, the western blotting method was used to measure the levels of PGC1α and NRF2 proteins. Moreover, cardiography was used to evaluate the functional parameters of the heart (ejection fraction & fractional shortening). Finally, the bioluminescence and ELISA methods were used to determine the content of adenosine triphosphate and citrate synthase. RESULTS: The cardiac function parameters, the mitochondrial ATP and the CS content in DC group mice were impaired in comparison with the other study groups and showed a decreasing trend (P < 0.001). The treatment with EX + UD extract was able to minimize the rate of these disorders and acted as a protector of mitochondrial function. There were significant differences in the expression levels of NRF2 (F = 17.7, P = 0.001) and PGC-1α (F = 43.7, P = 0.001) mitochondrial proteins among the different groups. The levels of these proteins were significantly reduced in the DC group in comparison with the HC group (P < 0.001). The treatment with EX or UD extract increased the expression of PGC-1α and NRF2 proteins in the heart muscle of animals in the DT and D-UD groups in comparison with the DC group (P < 0.05). Moreover, the expression of these proteins was more pronounced in the DT-UD group. There was not a significant difference between the DT-UD group and the HC group regarding the expression of these proteins (P > 0.05). CONCLUSIONS: The results of this study showed that treatment with EX and UD extract could treat the disorders which were caused by diabetes in the parameters of cardiac function. Moreover, it was able to improve the expression of the levels of proteins which were involved in mitochondrial biogenesis and its function. Finally, this kind of treatment could attract more attention to the roles of EX and UD extract in the prevention of cardiovascular complications in future studies.

Characterization of nettle leaves (Urtica dioica) as a novel source of protease for clotting dromedary milk by non-destructive methods.

This study investigates the valorization of the nettle leaves (Urtica dioica) as a novel source of a protease for clotting dromedary milk. The aim of this work is to study the effect of extracting pH on the enzymatic activity of nettle leaves extracts. The extraction was achieved in phosphate citrate buffer at different pH values (from 3 to 6.5) and the obtained extracts were used to coagulate dromedary milk. The characterization of the obtained extracts was carried out using non-destructive methods namely FT-MIR, fluorescence spectroscopy and turbiscan instrument. The extract prepared at pH = 4 had the highest proteolytic activity. The fluorescence and turbiscan measurements revealed a substantial effect of the pH value on chlorophyll residues extraction and stability, respectively. At an acidic environment (pH range of 3 - 4), the enzymatic extracts were unstable (with turbiscan stability index (TSI) values ~ 20), while at a nearly neutral pH value (pH range of 5 - 6.5), they were found to be more stable as indicated by the low TSI values ~ 1. The maximum milk-clotting activity (MCA) (0.021 U/mL) was obtained for the extracts prepared at pH = 4.

A potential role of nettle (Urtica dioica) extract on growth, biochemical changes and reproductive performance of convict cichlid (Amatitlania nigrofasciata).

This study was carried out to investigate the effects of methanolic extract of nettle (Urtica dioica) on growth, reproduction, biochemical and immunological parameters of female convict cichlid (Amatitlania nigrofasciata). For this purpose, 54 fish were distributed in 3 treatments included: without supplementation (control), 0.1 g (NE0.1), and 0.5 g (NE0.5) nettle extract per kilogram feed over 56 days. The highest final weight (4.2 ± 0.1 g), weight gain (2.8 ± 0.1 g), and specific growth rate (2.0 ± 0.0% day-1) were recorded in NE0.1 group. Higher and lower feed conversion ratio were obtained in control and NE0.1 treatments, respectively. Hepatosomatic and viscerosomatic indices in NE0.1 treatment were significantly lower compared with control treatment. Fish fed NE0.1 showed significantly lower glucose (55.2 ± 6.5 mg g-1), cholesterol (28.4 ± 3.3 mg g-1), and triglyceride (211.5 ± 39.0 mg g-1) levels. Total protein (36.3 ± 3.4 mg g-1) and albumin (2.7 ± 0.1 mg g-1) showed a marked increase in NE0.1 treatment. Same trend was observed in C3, C4, and IgM concentrations. NE0.1 showed the highest number of eggs per female (183.7 ± 10.2), hatching rate (97 ± 0.7%), and larval survival rate at 3 days post hatch (86.3 ± 0.6%) compared with the other treatments. These findings indicated that 0.1 g methanolic extract of nettle kg feed-1 could enhance growth, improve metabolic, and immune function of convict cichlid. Moreover, this study confirmed that appropriate dose of nettle can positively promote reproductive performance which makes it as a valuable and cost-effective herb in aquaculture industry.

Green and ecofriendly biosynthesis of selenium nanoparticles using Urtica dioica (stinging nettle) leaf extract: Antimicrobial and anticancer activity.

BACKGROUND/GOAL/AIM: Plant extract is affordable and does not require any particular conditions; rapid production of nanoparticles using plants offers more advantages than other approaches. Selenium nanoparticles (SeNPs) have received much attention in the last decade due to SeNPs diverse and different applications. Herein, this study aimed to biosynthesize SeNPs using aqueous extract of Urtica dioica leaf through green and ecofriendly method. Moreover to fully characterize SeNPs using different techniques, and to evaluate it for antimicrobial activity as well as anticancer activity. MAIN METHODS AND MAJOR RESULTS: SeNPs were biosynthesis using aqueous leaf extract of U. dioica (stinging nettle). The biosynthesized SeNPs were characterized using UV-visible spectroscopy (UV-Vis), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive electron spectroscopy (EDX), transmission electron microscopy (TEM), and thermal-gravimetric analysis (TGA). Antimicrobial and anticancer activities of biosynthesized SeNPs were assessed. Results illustrated that SeNPs exhibited promising antibacterial activity against Gram-positive and Gram-negative bacteria, as well as unicellular and multi-cellular fungi. Moreover, minimal-inhibitory concentration (MIC) of SeNPs against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus were 250, 31.25, and 500 µg mL-1 , respectively, while were 62.5, 15.62, 31.25, and 7.81 µg mL-1 against Candida albicans, Aspergillus fumigatus, Aspergillus niger, and Aspergillus flavus, respectively. The cytotoxicity of SeNPs was performed on Vero normal-cell line CCL-81, where IC50 was 173.2 µg mL-1 . CONCLUSIONS AND IMPLICATIONS: For the first time, aqueous stinging nettle leaf extract was utilized to biosynthesize SeNPs in a green method. SeNPs have outstanding antimicrobial-activity against pathogenic bacterial and fungal strains. Moreover, SeNPs have promising anticancer activity against HepG2 cancerous cell line without cytotoxicity on Vero normal cell line. Finally, the biosynthesized SeNPs via aqueous extract of stinging nettle leaf exhibited potential antibacterial, antifungal, and anticancer action, making them useful in the medical field.

Antibacterial and antioxidant activities of endophytic fungi and nettle (Urtica dioica L.) leaves as their host.

Nettle (Urtica dioica L), as a plant rich in biologically active compounds, is one of the most important plants used in herbal medicine. Studies have shown that this plant has antioxidant, antiplatelet, hypoglycemic and hypocholesterolemia effects. In this study, we characterized three Alternaria endophytic fungi isolated from their host U. dioica. We hypothesized that these endophytic fungi can produce new bioactive metabolites, which may possess the bioactive property with potential application in the medical and pharmaceutical industries. The antibacterial activity was evaluated against reference and isolated strains, including Methicillin-Resistant Staphylococcus aureus. A wide range of antimicrobial activities similar to those measured in nettle leaves was detected especially for Alternaria sorghi. Furthermore, the highest antioxidant activity detected with DPPH free radical scavenging was measured for A. sorghi and nettle leaves ethyl acetate extracts. In addition, whereas catalase activity was similar in the three isolated fungi and nettle leaves, total thiol content and superoxide dismutase activity were significantly higher in leaves. A. sorghi showed the best activities compared to other isolated fungi. The characterization and further production of bioactive compounds produced by this endophyte should be investigated to fight bacteria and especially those that develop drug multi-resistance.