Comparison the Soxhlet and Supercritical Fluid Extraction of Nettle Root (Urtica dioica L.)

The leaves of stinging nettle (Urtica dioica L.) are used for medical purposes since centuries while the nettle roots are applied only in the last decades. According to the latest researches the root of nettle contains many important ingredients, for example scopoletin, sterols, fatty acids, polysaccharides, polyphenols, minerals, etc. The polyphenols have antioxidant effect, reduce the hematological disorders, but also have anti-cancer and anti-bacteriological effects. The H-donating ability expresses the antioxidant activity.In this study two kinds of extraction techniques and three kinds of solvents have been applied. The extraction techniques were: Soxhlet extraction with 96% ethanol, Soxhlet extraction with n-hexane and supercritical fluid extraction (SFE) with CO2. All the measurements and the analysises were repeated three times.Comparing the yields of the three extraction methods it was established that the highest yield value was reached by Soxhlet extraction with ethanol. The Soxhlet extraction and the supercritical extraction has lower yield, the total polyphenol content and the H-donating ability of these extracts were low

Separation of valuable endogenous components from carrot peel by microwave extraction

With the rapid development of food technology, the amount of by-products generated is proportionally increasing as well. If not reused, by-products can pose a serious problem to our environment. In addition to managing and reusing such by-products, they may be valorised by extraction of valuable endogenous components using a less sophisticated, plain but modern technology such as microwave-assisted extraction. This new technique has been gaining popularity in recent years because compared to conventional methods, microwave-assisted extraction is characterised by shorter extraction times and lower solvent requirements. This preliminary experiment aimed to demonstrate that with the right operating parameters and solvent ratio, this method can be used for the efficient extraction of valuable endogenous components from carrot peels. To quantify the endogenous components, polyphenol content (TPC), antioxidant capacity (FRAP) and carotenoid content were investigated. The findings of this study showed that the optimal valuable substance extraction was obtained at 1:10 peelsolvent ratio at 100 W microwave power for fresh carrot peels, and 1:20 peel-solvent ratio at 800 W microwave power for dried carrot peels

Antimicrobial Effects of the Stinging Nettle (Urtica Dioica L.).

Nowadays increasing attention is being paid to herbs, one of the reasons is to avoid the undesirable side effects of synthetic drugs. This is the reason why the analysis of the antimicrobial activities of medicinal plants are increasingly in the focus of scientific experiments as well. One of the best-known medicinal plants is nettle. Among the nettle species in Hungary, Stinging nettle (Urtica dioica L.) can be found in the country and is most commonly utilised for medical purposes, with a focus on its leaves and roots. Nettle tea consumption is widespread in folk medicine for treating diabetes, allergies, abdominal pain, benign prostatic hyperplasia, rheumatoid arthritis and treatment of infections. This study gives a widespread summary of the reseach results about the antimicrobal impact of Stinging Nettle (Urtica dioica L.) in the scientific literature. The papers documented a positive effect of nettle for more than 30 Gram positive and Gram negative bacterias, yeasts and fungis

Changes in Total Polyphenol Content and Antioxidant Capacity of Stinging Nettle (Urtica dioica L.) from Spring to Autumn

Total polyphenol content and antioxidant/reducing capacity of stinging nettle (Urtica dioica L.) leaves and roots collected from wild-grown plants were investigated during the vegetation period. From both fresh and dried samples of leaves and roots, water extracts were prepared by brewing at 60, 80 and 100 °C for 3 hours, and ethanolic extracts of 20 % (v/v) and 70 % (v/v) by extracting at room temperature for 72 hours. The total polyphenol content was determined spectrophotometrically with Folin-Cioceltau reagent and the antioxidant capacity was measured by ferric reducing ability of plasma (FRAP) assay. Our results showed that the optimal harvest time is in the spring (April). Water extracts had the highest total polyphenol content and antioxidant capacity in this period. The amount of valuable compounds released increased by higher extraction temperature in both plant parts. In water extracts of nettle leaves, two times higher polyphenol content was obtained than in that of roots. Both kind of ethanolic extractions resulted in a higher polyphenol content in the leaves harvested in the spring period. For the roots, it was higher for samples collected in the autumn, which is also reflected in the values of antioxidant capacity. Water extracts of fresh leaves harvested in April had more than twice higher total polyphenol content than in October. For dried samples, raising the temperature did not cause a significant change in the total polyphenol content, however, it has resulted in increased antioxidant capacity both for the dried leaf and root samples

Antimicrobial effects of the stinging nettle (Urtica Dioica L.) review

Nowadays increasing attention is being paid to herbs, one of the reasons is to avoid the undesirable side effects of synthetic drugs. This is the reason why the analysis of the antimicrobial activities of medicinal plants are increasingly in the focus of scientific experiments as well. One of the best-known medicinal plants is nettle. Among the nettle species in Hungary, Stinging nettle (Urtica dioica L.) can be found in the country and is most commonly utilised for medical purposes, with a focus on its leaves and roots. Nettle tea consumption is widespread in folk medicine for treating diabetes, allergies, abdominal pain, benign prostatic hyperplasia, rheumatoid arthritis and treatment of infections. This study gives a widespread summary of the reseach results about the antimicrobal impact of Stinging Nettle (Urtica dioica L.) in the scientific literature. The papers documented a positive effect of nettle for more than 30 Gram positive and Gram negative bacterias, yeasts and fungis

Influence of the harvesting seasons on the polyphenol composition and antimicrobial activity of stinging nettle (Urtica dioica L.) extracts

The aim of our research was to study the water and ethanol extractable polyphenols of stinging nettle ( Urtica dioica L.) harvested in different seasons and to determine their antimicrobial activity against certain human pathogenic and food spoiling bacteria and yeasts

Biological Activities of Lactose-Based Prebiotics and Symbiosis with Probiotics on Controlling Osteoporosis, Blood-Lipid and Glucose Levels

Lactose-based prebiotics are synthesized by enzymatic- or microbial- biotransformation of lactose and have unique functional values. In this comprehensive review article, the biochemical mechanisms of controlling osteoporosis, blood-lipid, and glucose levels by lactose-based prebiotics and symbiosis with probiotics are reported along with the results of clinical investigations. Interaction between lactose-based prebiotics and probiotics reduces osteoporosis by (a) transforming insoluble inorganic salts to soluble and increasing their absorption to gut wall; (b) maintaining and protecting mineral absorption surface in the intestine; (c) increasing the expression of calcium-binding proteins in the gut wall; (d) remodeling osteoclasts and osteoblasts formation; (e) releasing bone modulating factors; and (f) degrading mineral complexing phytic acid. Lactose-based prebiotics with probiotics control lipid level in the bloodstream and tissue by (a) suppressing the expressions of lipogenic- genes and enzymes; (b) oxidizing fatty acids in muscle, liver, and adipose tissue; (c) binding cholesterol with cell membrane of probiotics and subsequent assimilation by probiotics; (d) enzymatic-transformations of bile acids; and (e) converting cholesterol to coprostanol and its defecation. Symbiosis of lactose-based prebiotics with probiotics affect plasma glucose level by (a) increasing the synthesis of gut hormones plasma peptide-YY, glucagon-like peptide-1 and glucagon-like peptide-2 from entero-endocrine L-cells; (b) altering glucose assimilation and metabolism; (c) suppressing systematic inflammation; (d) reducing oxidative stress; and (e) producing amino acids. Clinical investigations show that lactose-based prebiotic galacto-oligosaccharide improves mineral absorption and reduces hyperlipidemia. Another lactose-based prebiotic, lactulose, improves mineral absorption, and reduces hyperlipidemia and hyperglycemia. It is expected that this review article will be of benefit to food technologists and medical practitioners

Haemorheological and haemostatic alterations in coeliac disease and inflammatory bowel disease in comparison with non-coeliac, non-IBD subjects (HERMES) : a case-control study protocol

Haemorheological and haemostatic changes predispose to the development of arterial and venous thrombotic events; however, limited information is available on the status of these changes in coeliac disease (CeD) and inflammatory bowel disease (IBD). In this study, we aim to describe the haemorheological and haemostatic profiles of CeD and IBD patients in a Hungarian cohort of patients to investigate whether any alterations contribute to elevated thrombotic risk.This is a case-control study involving newly diagnosed and followed CeD and IBD patients with age-matched and sex-matched non-CeD, non-IBD subjects with an allocation ratio of 1:1:1.After informed consent is obtained, a detailed medical history will be collected, including venous and arterial thrombotic risk factors and medications. Symptoms in CeD patients will be assessed with the Gastrointestinal Symptoms Rating Scale, and disease activity in IBD patients will be determined by disease-specific scores. Dietary adherence will be assessed among CeD patients with a thorough interview together with a measurement of self-reported adherence, dietary knowledge and urine analysis (detection of gluten immunogenic peptides). In addition to routine laboratory parameters, haemorheological (ie, erythrocyte deformability and aggregation, viscosity of whole blood and plasma) and haemostatic parameters (eg, protein C, protein S and antithrombin) with immunological indicators (ie, coeliac-specific serology and antiphospholipid antibodies) will be measured from venous blood for every participant.Primary and secondary outcomes will be haemorheological and haemostatic parameters, respectively. Univariate and multivariate statistics will be used to compare CeD and IBD patients to control subjects. Subgroup analysis will be performed by disease type in IBD, (Crohn's disease and ulcerose colitis), dietary adherence in CeD, and disease activity in IBD and CeD.The study was approved by the Regional and Local Research Ethics Committee, University of Pécs (Ref. No. 6917). Findings will be disseminated at research conferences and in peer-reviewed journals.ISRCTN49677481