A Comparison between Bulgarian Tanacetum parthenium Essential Oil from Two Different Locations.

Tanacetum parthenium L. (Asteraceae) is a perennial herbaceous plant with a long-standing historical use in traditional medicine. Recently Tanacetum parthenium L. essential oil has been associated with a promising potential for future applications in the pharmaceutical industry, in the cosmetics industry, and in agriculture. Investigations on the essential oil (EO) have indicated antimicrobial, antioxidant, and repellent activity. The present study aimed to evaluate the chemical composition of Bulgarian T. parthenium essential oil from two different regions, to compare the results to those reported previously in the literature, and to point out some of its future applications. The essential oils of the air-dried flowering aerial parts were obtained by hydrodistillation using a Clevenger-type apparatus. The chemical composition was evaluated using gas chromatography with mass spectrometry (GC-MS). It was established that the oxygenated monoterpenes were the predominant terpene class, followed by the monoterpene hydrocarbons. Significant qualitative and quantitative differences between both samples were revealed. Camphor (50.90%), camphene (16.12%), and bornyl acetate (6.05%) were the major constituents in the feverfew EO from the western Rhodope Mountains, while in the EO from the central Balkan mountains camphor (45.54%), trans-chrysanthenyl acetate (13.87%), and camphene (13.03%) were the most abundant components.

Crithmum maritimum L.-Study on the Histochemical Localization of Essential Oil.

Crithmum maritimum L. is a perennial halophyte plant that is a medicinal herb known by people from different cultures since ancient times. However, the therapeutic potential of this halophyte has not been completely investigated, and the scientific data on it are limited. The purpose of the present study was to estimate the chemical composition of the essential oil (EO) obtained from the aerial parts of Crithmum maritimum L. growing wild in Bulgaria, as well as the histolocalization of secretory structures for the synthesis and accumulation of volatile oils. The results obtained on the EO composition of Bulgarian Crithmum maritimum L. provide an opportunity to reveal potential future applications in various fields, such as medicine, pharmacy, agriculture, food, and the cosmetic industry. Gas chromatography with mass spectrometry was performed to assess the chemical profile of the isolated EO. The phenylpropanoid dillapiole was identified as the major compound in the EO, accounting for 34.09% of the total EO. Monoterpene hydrocarbons represented 62.07% of the total oil composition. γ-Terpinene, D-limonene, and ß-pinene were the most abundant monoterpene hydrocarbons in the composition of the EO. In addition, histochemical localization of EO in the stem and leaves of Crithmum maritimum L. was carried out. The secretory structures were located in the cortical region of the stem and in the mesophyll tissues of the leaves in the form of secretory ducts. The performed histochemical analysis confirmed the lipophilic nature of the secretion from the duct cells. This is the first report related to the histolocalization and chemical composition of the EO from Bulgarian Crithmum maritimum L. Furthermore, our data indicate some potential possibilities for the evaluation of the therapeutic activity of the EO obtained from this plant species and outline its future applications as a therapeutic agent. Also, the EO from the studied halophyte plant has prominent potential to be used as a biopesticide, which is an environmentally friendly option compared to standard pesticides.

Chemical Composition and Future Perspectives of Essential Oil Obtained from a Wild Population of Stachys germanica L. Distributed in the Balkan Mountains in Bulgaria.

Stachys germanica L. (Lamiaceae) is a plant associated with a rich history in the traditional medicine of Iran, Turkey, and Serbia. However, researchers have not fully investigated the pharmacological potential of the herb, and scientific data on this plant species are limited. The aim of the current study was to evaluate the chemical composition of the essential oil (EO) obtained from the aerial parts of S. germanica L. growing wild in Bulgaria and to perform a comparative analysis of the chemical composition of EOs obtained from the same plant species from other geographical regions. For the evaluation of the chemical profile of the isolated EO, gas chromatographic analysis with mass spectrometry was performed. The most abundant terpene class was oxygenated monoterpenes, which accounted for 59.30% of the total EO composition. The bicyclic monoterpene camphor, as a compound of this class, was identified as the major constituent in the EO, accounting for 52.96% of the total oil composition. The chemical profile of Bulgarian EO is quite different compared to that of EOs from other regions. It is the only one to contain more than 50% camphor. In addition, EO contains significant amounts of the diterpene geranyl p-cymene (10.49%). This is the first study describing the chemical composition of EO from Bulgarian Stachys germanica L., and our results reveal some future perspectives for the evaluation of the biological activity of EO from the studied plant species as a new therapeutic agent or natural remedy targeting different medical conditions. The EO has a promising potential to be used as a biopesticide and repellent as well, an environmentally friendly and safer alternative to standard pesticides.

A Study of the Chemical Composition, Antioxidant Potential, and Acute Toxicity of Bulgarian Tanacetum vulgare L. Essential Oil.

Common tansy (Tanacetum vulgare L.) is a plant with medicinal properties that has traditionally been used in folk medicine for its anthelmintic, antispasmodic, and choleretic effects, for the treatment of diarrhea and digestive problems, and externally, as an insecticide in veterinary practices. In the current study, we investigated, for the first time, the chemical profile and antioxidant activity of essential oil from a wild population of T. vulgare L. growing in Bulgaria. Common tansy essential oil (EO), which is rich in bicyclic monoterpenes, was obtained using hydrodistillation and characterized by using gas chromatography-mass spectrometry (GC-MS). Thirty-seven compounds were identified in Bulgarian tansy EO. Among the major constituents were oxygenated monoterpenes, including compounds such as camphor (25.24%), trans-chrysantenyl acetate (18.35%), cis-verbenol (10.58%), thujone (6.06%), eucaliptol (5.99%), and α-campholenal (5.98%). The analysis results identified the essential oil from T. vulgare L. grown in the western Rhodope Mountains of Bulgaria as the camphor chemotype. Furthermore, its antioxidant activity was analyzed using the oxygen radical absorbance capacity (ORAC) method and was found to be 605.4 ± 49.3 µmol TE/mL. The essential oil was also tested for single-dose acute toxicity on Wistar rats and was found to be non-toxic by oral administration. The mean lethal dose by intraperitoneal administration was LD50 i.p. = 14.9 g/kg body weight. The results of the conducted study can serve as a basis for the evaluation and subsequent exploration of other pharmacotherapeutic effects of the essential oil obtained from the inflorescences of the Bulgarian species T. vulgare L.

Inhibitory Potential of Different Bilberry (Vaccinium myrtillus L.) Extracts on Human Salivary α-Amylase.

Recently, consumer preferences for bilberries have increased markedly. This fact is probably related to their natural constituents, such as phenolic compounds including anthocyanins and tannins, as well as the vitamins and minerals they contain. Phenolic compounds are known for their numerous beneficial effects on human health. Moreover, bilberry fruits have been shown to inhibit the activity of carbohydrate hydrolyzing enzymes, which can significantly decrease the postprandial increase in blood glucose levels. Thus, the aim of the present study is to investigate the inhibitory effect of Vaccinium myrtillus L. extracts on key enzyme α-amylase, linked to type 2 diabetes. No data have been published on the inhibitory properties of Vaccinium myrtillus L. fruits growing wild in Bulgaria against carbohydrate enzymes. Bilberry extracts were analyzed for total polyphenols, total anthocyanin content, antioxidant activity and their inhibitory properties against α-amylase. The contents of flavonols, anthocyanins and stilbenes were determined by HPLC analysis. The identified flavonols in the analyzed bilberry extracts were mainly represented by quercetin derivatives as rutinoside. The predominant anthocyanins for both aqueous and organic solvents were delphinidin-3-galactoside and malvidin-3-glucoside. The results revealed that bilberry extracts are effective inhibitors of α-amylase, with IC50 values from 20.8 to 194.8 µg GAE/mL. All the samples proved to have antioxidant activity measured by three different in vitro assays (FRAP, CUPRAC and DPPH). The inhibitory properties of V. myrtillus L. extracts may provide a new direction in the development and research of new pharmaceuticals for the suppression of postprandial hyperglycemia in diabetic patients.

A Study of the Chemical Composition, Acute and Subacute Toxicity of Bulgarian Tanacetum parthenium Essential Oil.

BACKGROUND: Tanacetum parthenium (L.) Sch.Bip. (T. parthenium) is an aromatic perennial plant belonging to the Asteraceae family, also known as feverfew. It is widely distributed in various regions of Europe and other parts of the world. The plant has a rich background in the traditional medicine of many nations and has been used as a remedy for fever, pain, inflammation, asthma, rheumatism, menstrual disorders, etc. Methods: GC-MS analysis was conducted to determine the chemical composition of the isolated essential oil (EO). Using the method proposed by Litchfield and Wilcoxon, the average lethal dose (LD50) of the EO on Wistar rats was determined for two routes of administration: oral (p.o.) and intraperitoneal (i.p.). The subacute toxicity of the EO was also tested by oral administration of a daily dose of 1.0 g/kg body weight (BW) for 28 days. The toxicity of the EO was evaluated by observing and evaluating changes in behavior, body weight, basic hematological and serum biochemical parameters, and histopathological changes of the internal organs. RESULTS: Thirty-seven volatile organic compounds representing 94.58% of the total oil composition were tentatively detected in the obtained T. parthenium EO. The dominant compounds were camphor (45.47%), trans-chrisantenyl acetate (21.65%), camphene (9.48%), and cis-isogeraniol (5.42%). The results showed that the EO was not toxic when administered in acute oral doses. The acute mean lethal dose for intraperitoneal administration was LD50 i.p. = 2.13 g/kg BW. In the subacute study involving administration of an oral dose of EO for 28 days, there were a number of changes in the hematological and serum biochemical parameters of the blood compared with the control group of animals. However, no symptoms of toxicity, changes in the body weight of the rats, death, or pathological changes in the histological indicators of the examined organs-brain, heart, stomach, liver, spleen and kidney-were found. Extrapolating the results obtained from the rat experiments, we can state that the EO is safe for use in doses below 1 g/kgBW for a period not exceeding one month.

Echinophora tenuifolia subsp. sibthorpiana-Study of the Histochemical Localization of Essential Oil.

BACKGROUND: Echinophora tenuifolia L. subsp. sibthorpiana is a perennial, aromatic plant used in traditional folk medicine and cuisine of the Mediterranean and the Middle East. However, scholars have not fully studied the pharmacological potential of the herb, and the scientific data on this plant species are limited. This study aimed to evaluate the chemical composition of the essential oil (EO) obtained from the aerial parts of E. tenuifolia subsp. sibthorpiana growing wild in Bulgaria and to perform histochemical analysis. METHODS: A microscopic histochemical analysis and gas chromatography with mass spectrometry were performed. RESULTS: The histochemical analysis confirmed the presence of terpenes in the stem and leaf of E. tenuifolia subsp. sibthorpiana. The phenylpropanoid methyleugenol was identified as the main compound in the EO, representing 48.13% of the total oil composition. There were also found considerable amounts of monoterpene hydrocarbons, representing 41.68% of the total EO. Alpha-phellandrene, o-cymene, and ß-phellandrene were the most abundant monoterpene hydrocarbons. CONCLUSION: This is the first histochemical analysis performed on E. tenuifolia subsp. sibthorpiana. This is the first report of the EO composition from Bulgarian E. tenuifolia subsp. sibthorpiana, and our results indicate some future possibilities for evaluating of the biological activity of the EO of E. tenuifolia subsp. sibthorpiana and highlight the potential future use of the EO of this plant species. E. tenuifolia L. subsp. sibthorpiana EO possesses a good potential for use as a biopesticide and repellent an environmentally friendly alternative of synthetic pesticides.

Comparison between the Chemical Composition of Essential Oil from Commercial Products and Biocultivated Lavandula angustifolia Mill.

The main aim of this study was to assess the differences in the chemical composition of essential oil from biocultivated Lavandula angustifolia in the Thracian Lowland floristic region, Bulgaria, and commercially available products from Bulgarian markets. Following the analytical results conducted with gas chromatography-mass spectrometry, we have established some differences in the chemical composition of the tested samples. The essential oil of biocultivated lavender contained 35 compounds, which represent 94.13% of the total oil. Samples from commercial products contained 28-42 compounds that represent 93.03-98.69% of the total oil. All the examined samples were rich in monoterpene hydrocarbons (1.68-12.77%), oxygenated monoterpenes (70.42-87.96%), sesquiterpene hydrocarbons (4.03-13.78%), and oxygenated sesquiterpenes (0.14-0.76%). The dominant components in all examined samples were linalool (20.0-45.0%) and linalyl acetate (20.79-39.91%). All the examined commercial samples contained linalool and linalyl acetate as was described in the European Pharmacopoeia, but in one of the samples, the quality of linalyl acetate is lower than that recommended in the European Pharmacopoeia.

Chemical Composition and Histochemical Localization of Essential Oil from Wild and Cultivated Rhaponticum carthamoides Roots and Rhizomes.

Rhaponticum carthamoides (Willd.) Iljin is not only a source of phytosteroids and flavonoids, but is also source of essential oil (EO). This study evaluated the volatile metabolic constituents and histochemical localization of root and rhizome essential oils (EOs) from R. carthamoides populations wild-grown in Russia and cultivated in Bulgaria. The performed histochemical analysis confirmed the presence of lipophilic substances in the secretory ducts of the examined roots and rhizomes. Both EOs were obtained by hydrodistillation and further analyzed by gas chromatography with mass detection. The results showed differences between the chemical compositions of both EOs. Forty-six components were tentatively identified in R. carthamoides oil from the wild population, with ß-selinene (4.77%), estragole (6.32%), D-carvone (6.37%), cyperene (8.78%), and ledene oxide (11.52%) being the major constituents. In the EO isolated from cultivated R. carthamoides, twenty-three compounds were tentatively identified, with humulene (7.68%), ß-elemene (10.76%), humulene-1,2-epoxide (11.55%), ledene oxide (13.50%), and δ-elemene (19.08%) predominating. This is the first report describing the histolocalization and chemical profile of EO from R. carthamoides cultivated in Bulgaria. Further research on the cultivation of R. carthamoides in Bulgaria would affect the relationship between its chemical composition and pharmacological effects.

Polysaccharides and Their Derivatives as Potential Antiviral Molecules.

In the current context of the COVID-19 pandemic, it appears that our scientific resources and the medical community are not sufficiently developed to combat rapid viral spread all over the world. A number of viruses causing epidemics have already disseminated across the world in the last few years, such as the dengue or chinkungunya virus, the Ebola virus, and other coronavirus families such as Middle East respiratory syndrome (MERS-CoV) and severe acute respiratory syndrome (SARS-CoV). The outbreaks of these infectious diseases have demonstrated the difficulty of treating an epidemic before the creation of vaccine. Different antiviral drugs already exist. However, several of them cause side effects or have lost their efficiency because of virus mutations. It is essential to develop new antiviral strategies, but ones that rely on more natural compounds to decrease the secondary effects. Polysaccharides, which have come to be known in recent years for their medicinal properties, including antiviral activities, are an excellent alternative. They are essential for the metabolism of plants, microorganisms, and animals, and are directly extractible. Polysaccharides have attracted more and more attention due to their therapeutic properties, low toxicity, and availability, and seem to be attractive candidates as antiviral drugs of tomorrow.

Plant-Based Diet as a Strategy for Weight Control.

According to the World Health Organization, obesity has nearly tripled since the 1970s. Obesity and overweight are major risk factors for cardiovascular diseases, diabetes, inflammatory-mediated diseases, and other serious medical conditions. Moreover, recent data suggest that obesity, overweight, diabetes, and cardiovascular diseases are risk factors for COVID-19-related mortality. Different strategies for weight control have been introduced over the last two decades. Unfortunately, these strategies have shown little effect. At the same time, many studies show that plants might be the key to a successful strategy for weight control. Following the PRISMA guidelines for conducting systematic reviews, a search was conducted in PubMed, Web of Science, Scopus, and Embase using the following keywords: obesity, globesity, vegan, plant-based diet, etc. Our results show that vegan diets are associated with improved gut microbiota symbiosis, increased insulin sensitivity, activation of peroxisome proliferator-activated receptors, and over-expression of mitochondrial uncoupling proteins. The key features of this diet are reduced calorie density and reduced cholesterol intake. The combination of these two factors is the essence of the efficiency of this approach to weight control. Our data suggest that plant-based/vegan diets might play a significant role in future strategies for reducing body weight.

Plant Adaptogens-History and Future Perspectives.

Adaptogens are synthetic compounds (bromantane, levamisole, aphobazole, bemethyl, etc.) or plant extracts that have the ability to enhance the body's stability against physical loads without increasing oxygen consumption. Extracts from Panax ginseng, Eleutherococcus senticosus, Rhaponticum carthamoides, Rhodiola rosea, and Schisandra chinensis are considered to be naturally occurring adaptogens and, in particular, plant adaptogens. The aim of this study is to evaluate the use of plant adaptogens in the past and now, as well as to outline the prospects of their future applications. The use of natural adaptogens by humans has a rich history-they are used in recovery from illness, physical weakness, memory impairment, and other conditions. About 50 years ago, plant adaptogens were first used in professional sports due to their high potential to increase the body's resistance to stress and to improve physical endurance. Although now many people take plant adaptogens, the clinical trials on human are limited. The data from the meta-analysis showed that plant adaptogens could provide a number of benefits in the treatment of chronic fatigue, cognitive impairment, and immune protection. In the future, there is great potential to register medicinal products that contain plant adaptogens for therapeutic purposes.

Study of prebiotic potential and antioxidant activity in Plantago spp. leaves after enzymatic hydrolysis with hemicellulase and xylanase.

The leaves of Plantago species have been known as a rich source of polysaccharides, polyphenols, and iridoids. In the recent years, some authors have examined the relative influence of carbohydrate compositions and polyphenols on their antioxidant and prebiotic activity. In this study enzymatic hydrolysis of Plantago major, Plantago lanceolata, and Plantago media leaves with hemicellulase and xylanase was carried out. The chemical composition of the enzyme-derived hydrolysis products was determined. Their antioxidant activity was evaluated using 2,2-diphenyl-2-picryl-hydrazyl-hydrate, ferric reducing antioxidant power, and cupric reducing antioxidant capacity assays. The utilization of the carbohydrate complex from the obtained hydrolysates to stimulate the production of certain glycohydrolases from Lactobacillus plantarum probiotic strains was investigated. The HPLC analysis of the hydrolysis products showed the presence of galactose and arabinose in 1:3 and 1:4 ratios. The highest concentration of total sugars was determined in P. major hydrolysates with hemicellulase (386.71 mg/g dry weight). The antioxidant activity according to the three methods was the highest in P. media hydrolysates, which correlated with their total phenolic concentration. L. plantarum S27 showed the highest values of α-galactosidase activity at the 24-h fermentation process when it was cultivated in a broth with the presence of P. major hydrolysates with hemicellulase and xylanase (0.129 U/mg and 0.133 U/mg, respectively).

Enzymatic Hydrolysis of Water Extractable Polysaccharides from Leaves of Plantago major L.

BACKGROUND: Plantago major L. leaves have been used for centuries by the traditional medicine in the treatment of infectious disorders of the respiratory, urinary and digestive tracts. Researchers have reported that hot water extracts of Plantago major possess a broad-spectrum of anticancer, antioxidant and antiviral activities, as well as activities which modulate cell-mediated immunity. Their beneficial properties may be due to the significant content of polysaccharides. The polysaccharides that have been isolated from the leaves of Plantago major L. have different structures - pectic substances, galactans, arabinogalactans, glucomannans. AIM: The aim of this paper was to study the correlation between the structure of the water extractable polysaccharides isolated from Plantago major L. leaves and their enzymatic hydrolysis with different carbohydrate hydrolases. MATERIALS AND METHODS: The hydrolysis reactions were performed with the enzymes hemicellulase and mannanase. Spectrophotometric total reducing sugars assay was used to examine the hydrolysis yield. The monosaccharide and oligosaccharide compositions were determined using HPLC analysis. RESULTS: The highest hydrolysis yield of the water extractable polysaccharides from Plantago major leaves was obtained by treatment with hemicellulase. The hydrolysis yield increased with the augmentation of the ratio of enzyme to polysaccharide. Galactose was the prevalent monosaccharide identified in the composition of the isolated polysaccharides. Oligosaccharides with different degree of polymerization were also detected. CONCLUSION: The enzymatic hydrolysis of water extractable polysaccharides from Plantago major leaves allows us to obtain different types of oligosaccharides with beneficial effects on both human health and industry.

Effect of Extracts of Bilberries (Vaccinium myrtillus L.) on Amyloglucosidase and α-Glucosidase Activity.

BACKGROUND: Vaccinium myrtillus L. is a species belonging to the genus Vaccinium of the family Ericaceae. Bilberries have drawn attention due to the multiple benefits for the human health, including antioxidant, anti-inflammatory, anticancer, anti-neurodegenerative, and cardioprotective effects. Recently, bilberries were shown to inhibit the activity of carbohydrate-hydrolysing enzymes that can help reduce the intensity of the metabolic syndrome and prevent type 2 diabetes. AIM: In this study, we investigated the α-glucosidase and amyloglucosidase inhibitory activities of polyphenol-rich extracts from fruit of Vaccinium myrtillus L. from different regions in Bulgaria. MATERIALS AND METHODS: The total phenolic content was determined spectrophotometrically using the Folin-Ciocalteu method. With HPLC analysis, phenolic acid composition of extracts was assessed. Enzymatic inhibitory activities were determined according to the methodology by Borooah et al. (1961), and Dewi et al. (2007). Amyloglucosidase assay and α-glucosidase assay were used to measure the inhibition potential of bilberries' extracts. RESULTS: Phenolic compound content ranged from 1299.60 mg to 510.88 mg GAE/100 g for organic extracts and from 453.63 mg to 290.83 mg GAE/100 g for aqueous extracts. Based on qualitative HPLC analyses, gallic acid and chlorogenic acid were found to be among the major phenolic acids present in bilberries. Methanol and aqueous extracts there were found to be effective inhibitors of α-glucosidase with an IC50 value of 20 µg GAE/ml and 55 µg GAE/ml, respectively. CONCLUSION: The inhibitory activity of bilberries' extracts towards α-glucosidase offers the patients with type 2 diabetes the opportunity to manage their own glycaemic levels with a diet.