Study of the biochemical composition and the active substances of nettle as a functional food

Study of the biochemical composition and the active substances of nettle  as a functional food                                                                                                                                                                                                                            

Competence Center of Food and Fermentation Technologies

Author: Ingrid Sumeri, PhD

The main health determinants of nettle are the ability to release the body from poisons, improve metabolism, strengthen the immune system, improve blood flow, empower energy, reduce menstruation and also menopaus-related ailments, improve skin problems, protect the kidneys and gall bladder, reduce inflammation, lower blood pressure, relieve discomfort from hemorrhoids and improve respiratory conditions, relieve allergies (allergic rhinitis) and joint diseases (rheumatoid arthritis). In addition, the paroxysis is anti-inflammatory, analgesic (the reduction of intestinal peristalsis), antioxidant, diuretic and inhibitory effect on ulcers (1.2)

Behind the impressive health-enhancing effects of stinging nettle, it contains a variety of bioactive compounds, many of which have antioxidant properties. Antioxidants have the ability to bind free radicals resulting from biochemical processes, which may adversely affect cells in excess amounts. Complex antioxidants systems are developed in plants and animals. These include antioxidative enzymes such as superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase and non-enzymatic substrates, such as glutathione, uric acid, lipoeic acid, bilirubin, coenzyme Q, vitamin C (L-ascorbic acid), vitamin A (retinol), vitamin E (tocopherol), flavonoids, carotenoids (e.g, astaxanthin, zeaxanthin), Lycopene, Phospvitin, bioflavonoid resveratol, tein compounds in the green tees and others. Some biomolecule is also considered as a biologically active and clinical point of view as essential antioxidants such as transferrin, Ferritin, Lactoferrin, ceruloplasmin, Haemthitis, Haptoglobin (3, 4, 5, 6). Separately, it may be called phenols, which also have the capacity to bind free radicals, due to the hydroxyl groups contained therein. Several studies have shown antioxidant effects of phenolic compounds (7). In the strait oil is a decalted agglutinin, Acettophenone, alkaloids, chlorogenic acid, butyric acid, chlorophyll, caffeine acid, carbonus acid, choline, histamine, chanteinic acid, formic acid, vitamin B5, or pantothenic acid, Coproporphyrin, lectin, Letyine, Lignaan, linoleic acid, linolenic, palmitic, Ksantofülle, Kvertsetin, Skopoletin, beta-sitosteol, tartaric acid, serotonin, Stigmasterol, terpenes, violaxanine and succinic acid (8).

 

The following is a brief description of the characteristics of some of the biologically active compounds mentioned:

  • The Glycoside beta-sitosterol and its close compounds daukosterool and Campesterol have a connection with testosterone-dependent, benign prostatic hyperplasia. (1) beta-sitosterol and Daukosterool also play a role in the treatment of lung cancer (9.10).
  • The Scopoletin is a type of bacterial, as well as known pathogens, Staphylococcus aureus, Klebsiella pneumoniae and Pseudomonas aeruginosa for Growth and reproduction (2). The Skopoletin also has anti-inflammatory activity and is used to treat bronchitis and asthma. Also, the Skopoletine hormone regulates the activity of serotonin, which helps to reduce anxiety and depression (11).
  • Stigmasterool, unsaturated Phytosteolil, is a joint stiffness, swelling and pain effect in arthritis. Stigmasterol is a precursors for the production of semi-synthetic progesterone, which in turn has an important physiological role in regulatory and tissue reconstruction mechanisms associated with oestrogen, as well as an intermediate compound in the biosynthesis of androgens, estrogens and Corticoids. It is also used as a precurcompound in vitamin D3. Studies have shown that Stigmasterol is useful in preventing certain forms of cancer, including ovarian, prostate, breast, and colon cancer. It also has anti-oxidative, hypoglycaemic and thyroid inhibitory effects (12).
  • Kvertsetin is a flavonoid with anti-inflammatory and immune-enhancing effects. Kvertsetin inhibits the production of cyclooxygenase and Lipoxygenase, which in turn regulate compounds that mediate inflammation in the body, leukotriene and prostaglandins (13)
  • Pantothenic acid or vitamin B5 is useful in the treatment of acne (14).
  • Serotonin is involved in the regulation of many important functions of the human body, such as sleep, hunger, thirst, mood and sexual activity (15). Serotonin has ntioxidative, anti-inflammatory, anticancer and depression-and anxiety-reducing effects (16, 17).
  • Lignaans such as (+)-Neoolil, Isolarikiresinol and pinoresinol have a positive effect on benign prostatic hyperplasia, due to an affinity for globulin in human sex hormone (18).
  • Caffeine acid is an antioxidant in vitro and in vivo. It also has an immunomodulatory and anti-inflammatory effect (19).
  • Histamine regulates the function of the human polymorphonuclear leukocytes (Polymorphophoto leukocytes, PMN) and reduces the risk of leukotriene B4 (inflammation-associated molecule) by inhibiting the biosynthesis of at least three of its induction pathways. The presence of histamine in the ear joint is one possible cause of the last anti-inflammatory action. 

Xantophylls is a vegetable pigment, belonging to the Carotenoid family, which has a number of healing properties. For example, Xantophylls lutein and zeaxanthin are known antioxidants and, in particular, improve the work of visual organs. 21

14-Octtakosanol is a beneficial compound in controlling fat metabolism and lowering cholesterol. Additional evidence exists to prove that Oktakosanols improve the performance of athletes. Also, the benefits of oktakosanols are useful in the treatment of gastric ulcers and neuronal diseases (22).

 

Chemical analyses performed from different nettle preparations

The project carried out analyses of nettle powders, freshly squeezed and deep-frozen nettle powder and 30% ethanol extract.

 The analysis of the freshly squeezed and deep-frozen nettle samples. For the purpose of determining the content of mineral substances, as well as the deep-frozen nettle-type B vitamins, an analysis was ordered from the Food and Veterinary Laboratory. Vitamin C in the determination of fresh netic and the determination of B-group vitamins in the Netgut extract was carried out at the Centre for food and fermentation technologies. The determination of antioxidants and polyphenolic compounds was performed at the Institute of Chemistry and Biotechnology of Tallinn University of Technology.

A vitamin C content of 4.39 mg/100g was determined in the fresh concellation. According to the literature, the vitamin C content in the netic may also be 13 mg/100g.  The daily dose of vitamin C for adults is 90 mg for males and 75 mg for females. (The recommended Daily Reference values for vitamins and minerals (PDR), here and further, are based on United States Food and Drug Administration (FDA), World Health Organization (WHO), European Union Directive (EU) and many other public and private bodies in the US and the UK (23).  

In the fresh nettle juice, the group B vitamins Vitamin B1 (thiamin)  was 1.06 mg/100g. The recommended daily dose for adults is 1.4 mg, no health problems due to overdose have been observed.

The quantity of vitamin B2 (riboflavin) was determined to be 0.22 mg/100g. The daily norm of this vitamin is 1.6 mg. The content of B3 vitamin (nicotinamide and nicotinic acid) was less than 0.04 mg/100g. The recommended daily intake is 18 mg. B5 (Pantothenic acid) was obtained in the fresh nettle uterus 0.83 mg/100g. The daily norm of pantothenic acid is 6 mg/100g. Vitamin B6 was measured 0.38 mg/100g, the recommended daily intake is 2 mg. 

The beta-carotene content of fresh nettle is 557 μg/100g.

In most European countries, the recommended amount of beta carotene is based on the fact that the 4.8 mg beta carotene corresponds to 800 micrograms of vitamin A. There are conclusions from epidemiological studies that in order to potentially be healthy, human plasma should include 0.4 Micromol/L beta-carotene. 

In parallel, the determination of the beta-carotene content was also ordered with Naadipon. The last value was far exceeded by the concat (2423 μg/100g). The potassium content of the plaque, which was 0.33 g/100g, was also determined.

In dried nettle powder, the recommended daily dose is 80 μg of vitamin K, which was measured at 552 μg/100g. Higher amounts may damage the liver. However, the recommended consumption rates for vitamin K vary in different countries. In general, Europe has taken the view that a daily dose of vitamin K could be 1 microgram/1kg body weight (EFSA NDA Panel (EFSA Panel is Dietetic Products, Nutrition and articles).

 The iron content in the nettle powder was measured at 9 mg/100g. The recommended daily intake of iron for adults is 15 mg.  Iron is better absorbed by Heemse Iron, which can be mainly derived from animal products (approximately 20% of the iron consumed), and mainly non-heseed iron is absorbed from the plant in food by approximately 5% of the consumed quantity. Absorption of iron is improved when consumed with vitamin C rich foods (25). Calcium was measured in nettle powder 2242.6 mg/100g. The recommended daily intake of calcium is 1000 mg. Calcium is beneficial both in terms of bone health and in the prevention of a number of cancers (26).

The netter-Starter Vitamin B1 content was measured 0.45 mg/100 ml; The B3 vitamin was 0.66 mg/100ml, no B2 or B5 vitamin, and pyridoxine was determined as 0.28 mg/100 ml.

In addition to iron (< 5mg/kg) and calcium (52.6 mg/100g), the needle extract also contained a potassium content of 407 mg/kg. The recommended daily intake of potassium is 3500 mg. In addition, zinc was also determined from the nettle extract, resulting in 0.3 mg/kg. The recommended daily dose of this mineral is 15 mg. Zinc is associated with a number of aspects of cell secretion. This is necessary for approximately 100 enzyme catalytical activity. Zinc also plays a role in the functioning of the immune system (27).

Nettle extract aqueous antioxidants 18.67 ± 0.12 μg/VCE/ml, (3.29 ± 0.02 g/L)

Nettleextract t fat-soluble antioxidants 26.99 ± 1.13 μg/TE/ml (6.75 ± 0.03 g/l)

Polyphenols 4,91 ± 0.22 μg/ml (0.83 ± 0.04 g/L)

Analysis suggests that nettle is rich in antioxidants, including polyphenols. For comparison, an article analysing the antioxidant content of tea drinks reached a maximum result of 9.79 mmol/L (28).

Summary

On the basis of the literature data, it can be argued that Nettle has a wide range of human health benefits, thanks to its large amount of bio-active substances. This was also demonstrated by the antioxidant analysis performed at the Tallinn University of Technology, Institute of Chemistry and Biotechnology. However, it should be noted that many studies are still at the level of the in vitro tests or experiments on laboratory animals. However, these results cannot always be extrapolated to humans. The minerals and vitamins analysed, in particular, can be used to identify high levels of calcium in the nettle powder, as well as thiamin in the freshly squeezed nettle. The nettle or the extract can be prepared with drinks with an interesting flavour.

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