Potential of Tetradenia riparia leaf essential oil and its fractions in controlling Aedes aegypti and Rhipicephalus microplus larvae

Tetradenia riparia (Hochst.) Codd (Lamiaceae) is a shrub, commonly known as ginger bush or false myrrh, and several studies have shown that T. riparia exhibits a variety of biological properties. This study aimed to determine the chemical composition of T. riparia essential oil and its fractions, investigate their anticholinesterase activity, and assess their larvicidal activity against the cattle tick Rhipicephalus microplus and the mosquito Aedes aegypti. Eleven essential oil fractions were obtained by fractionation and analyzed by gas chromatography/mass spectrometry. Larvicidal activity against R. microplus and third-instar A. aegypti was assessed using a larval packet test and a larval immersion test, respectively. Anticholinesterase activity was determined by a bioautographic method. Forty-nine compounds were identified in the essential oil, of which the major classes were oxygenated sesquiterpenes (45.95%) and sesquiterpene hydrocarbons (35.20%) and the major components were isospathulenol (17.40%), ß-caryophyllene (15.61%), 14-hydroxy-9-epi-caryophyllene (10.07%), 14-hydroxy-α-muurolene (8.32%), and 9ß,13ß-epoxy-7-abietene (5.53%). Bioassays showed that T. riparia essential oil (LC50 = 1.56 µg/mL) and FR3 (LC50 = 0.30 µg/mL) were the most active against R. microplus and A. aegypti larvae, respectively. The essential oil and FR1, FR2, and FR3 exhibited acetylcholinesterase inhibitory activity. These results indicate that T. riparia essential oil and its fractions hold promise in the development of novel, environmentally safe agents for the control of R. microplus and A. aegypti larvae.

Estudo do potencial antiviral sobre o Sars-Cov-2 dos compostos identificados no extrato bruto das folhas de Tetradenia riparia / Study of antiviral potential on Sars-Cov-2 of compounds identified in Tetradenia riparia leaves crude extract / Estudio del potencial antiviral sobre el Sars-Cov-2 de los componentes identificados en el extracto crudo de las hojas de Tetradenia riparia

A COVID-19 surgiu de forma repentina, acometendo milhões de pessoas e causando muitas mortes no mundo todo. Diante disso, torna-se necessário a busca de substâncias bioativas com propriedades antivirais. No Brasil, a espécie Tetradenia riparia foi inserida como planta ornamental exótica, com aroma intenso e agradável, sendo cultivada em parques, jardins, residenciais e hortos. O objetivo deste estudo foi identificar compostos presentes no extrato bruto das folhas de Tetradenia riparia com interesse antiviral. O extrato bruto das folhas secas foi obtido por maceração dinâmica por esgotamento do solvente e após, concentrado em evaporador rotativo. A composição química do extrato bruto foi analisada por cromatografia líquida de ultra eficiência acoplada à espectrometria de massas de alta resolução (UHPLC-ESI/qTOF). Foram identificados 31 compostos que foram investigados por meio de levantamento bibliográfico quanto ao seu potencial anti- SARS-CoV-2. Os compostos rosmanol, procianidina, cianidina, betulina, ácido betulínico e o ácido sagerínico, apresentaram potencial atividade antiviral sobre o SARS-CoV-2. Esta investigação é promissora, indicando possivelmente que no extrato bruto das folhas de T. ripária existem compostos que podem combater o SARS-CoV-2. Neste sentido, estudos de ancoramento molecular (docking) e análises in silico sobre a proteína Mpro do vírus devem ser realizadas corroborando desta forma a ação dos compostos identificados.

COVID-19 appeared suddenly, affecting millions of people and causing many deaths worldwide. Therefore, it is necessary to search for bioactive substances with antiviral properties. In Brazil, Tetradenia riparia was inserted as an exotic ornamental plant, with an intense and pleasant aroma, cultivated in parks, residential and vegetable gardens. This study aimed to identify compounds present in the crude extract of Tetradenia riparia leaves with antiviral interest. The crude extract of the dried leaves was obtained by dynamic maceration with solvent exhaustion and then concentrated in a rotary evaporator. The chemical composition of the crude extract was analyzed by ultra- performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC- ESI/qTOF). We identified 31 compounds investigated through a literature review for their anti- SARS-CoV-2 potential. The compounds rosmanol, procyanidin, cyanidin, betulin, betulinic acid, and sagerinic acid showed potential antiviral activity against SARS-CoV-2. Therefore, this investigation is promising, possibly indicating that in the crude extract of T. riparia leaves, there are compounds that can fight SARS-CoV-2. In this sense, molecular docking studies and in silico analyzes on the virus Mpro protein must be carried out, thus corroborating the action of the identified compounds.

SARS-CoV-19 ha aparecido repentinamente, afectando a millones de personas y causando muchas muertes en todo el mundo. Por ello, se hace necesaria la búsqueda de sustancias bioactivas con propiedades antivirales. En Brasil, la especie Tetradenia riparia ha sido introducida como planta ornamental exótica, con un aroma intenso y agradable, siendo cultivada en parques, jardines, residencias y centros de jardinería. El objetivo de este estudio fue identificar los compuestos presentes en el extracto crudo de las hojas de Tetradenia riparia con interés antiviral. El extracto crudo de las hojas secas se obtuvo por maceración dinámica por agotamiento del disolvente y después, se concentró en el evaporador rotatorio. La composición química del extracto crudo se analizó mediante cromatografía líquida de ultra rendimiento acoplada a espectrometría de masas de alto rendimiento (UHPLC-ESI/qTOF). Se identificaron 31 compuestos y se investigó su potencial anti-SARS-CoV-2 mediante un estudio bibliográfico. Los compuestos rosmanol, procianidina, cianidina, betulina, ácido betulínico y ácido sagerínico, mostraron una potencial actividad antiviral sobre el SARS-CoV-2. Esta investigación es prometedora, pues posiblemente indica que en el extracto crudo de las hojas de T. riparia hay compuestos que pueden combatir el SARS-CoV-2. En este sentido, deben realizarse estudios de docking y análisis in silico sobre la proteína Mpro del virus para corroborar la acción de los compuestos identificados.

Gmelina arborea- an indigenous timber species of India with high medicinal value: A review on its pharmacology, pharmacognosy and phytochemistry.

ETHNOPHARMACOLOGICAL SIGNIFICANCE: Gmelina arborea Roxb.ex Smith, a fast-growing deciduous tree belongs to the family Lamiaceae, and is an important plantation species in many tropical areas around the world. The species is naturally distributed in semi-deciduous forests in tropical/subtropical regions of South East Asia. The tree is also an important medicinal plant in the Indian Systems of Medicine. The whole plant is used in medicine. It is astringent, bitter, digestive, cardiotonic, diuretic, laxative and pulmonary and nervine tonic. It improves digestion, memory, helps overcome giddiness and is useful in burning sensation, fever, thirst, emaciation, heart diseases, nervous disorders and piles. The roots are acrid, bitter-sweet in taste, stomachic, tonic, laxative, galactagogue and antihelmintic. The flowers are sweet, refrigerant, bitter, astringent and acrid, and are used in treating leprosy and skin diseases. The fruits are acrid, sour, sweet, refrigerant, bitter, astringent, aphrodisiac, trichogenous, alterant and tonic. Fruits are edible and also used for promoting hair growth and in treating anaemia, leprosy, ulcers, constipation, leucorrhoea and colitis. The leaves are a good fodder also. The major bioactive compounds extracted from different parts of G. arborea are arboreal, verbascoside, tyrosol, iridoids, phenylpropanoid glycoside, premnazole, martynoside, iridoid glycosides, balanophonin, gmelinol, isoarboreol apigenin, umbelliferone etc. AIM OF THE REVIEW: This review provides an insight into the medicinal aspects of G. arborea. It provides the latest information on phytochemistry, pharmacological activities and traditional uses of G.arborea. MATERIALS AND METHODS: Information on G. arborea was gathered from various sources like textbooks, literature, databases such as PubMed, Science Direct, Wiley, Springer, Taylor and Francis, Scopus, Inflibnet, Sci-Finder and Google Scholar. RESULTS: Sixty-nine phytochemicals which include lignans, acylated iridoid glycosides, acylated rhamnopyranoses, flavonoids, flavones, flavone glycosides have been isolated. Many of them have been characterized for their pharmacological activity. Several researchers have identified bioactive phytochemicals like luteolin, iridoid alkaloids from the leaves, hentriacontanol and lignans such as arboreol, isoarboreol, arborone, gmelanone, gummadiol from the heartwood, flavon glycosides in roots. The extracts are reported to have wound-healing and antidiarrheal properties. Various studies demonstrated that G.arborea and its constituents possess several pharmacological activities like anti-oxidant, anti-diabetic, anti-inflammatory, antiulcer, analgesic, anti-nociceptive, anticancer and wound healing activities. CONCLUSION: G. arborea is a valuable medicinal plant used traditionally in the Indian Systems of Medicine (ISM - Ayurveda and Unani) to treat a wide variety of ailments. These phytochemicals are highly bioactive and exhibit various pharmacological activities. However, pharmacological activities of many compounds which have been identified, are yet to be understood.

Toxicity and oviposition deterrence of essential oils of Clinopodium nubigenum and Lavandula angustifolia against the myiasis-inducing blowfly Lucilia sericata.

Cutaneous myiasis is a severe worldwide medical and veterinary issue. In this trial the essential oil (EO) of the Andean medicinal plant species Clinopodium nubigenum (Kunth) Kuntze was evaluated for its bioactivity against the myiasis-inducing blowfly Lucilia sericata (Meigen) (Diptera Calliphoridae) and compared with that of the well-known medicinal plant species Lavandula angustifolia Mill. The EOs were analysed and tested in laboratory for their oviposition deterrence and toxicity against L. sericata adults. The physiology of EO toxicity was evaluated by enzymatic inhibition tests. The antibacterial and antifungal properties of the EOs were tested as well. At 0.8 µL cm-2, both EOs completely deterred L. sericata oviposition up to 3 hours. After 24 h, the oviposition deterrence was still 82.7% for L. angustifolia and the 89.5% for C. nubigenum. The two EOs were also toxic to eggs and adults of L. sericata. By contact/fumigation, the EOs, the LC50 values against the eggs were 0.07 and 0.48 µL cm-2 while, by topical application on the adults, LD50 values were 0.278 and 0.393 µL per individual for C. nubigenum and L. angustifolia EOs, respectively. Inhibition of acetylcholine esterase of L. sericata by EOs (IC50 = 67.450 and 79.495 mg L-1 for C. nubigenum and L. angustifolia, respectively) suggested that the neural sites are targets of the EO toxicity. Finally, the observed antibacterial and antifungal properties of C. nubigenum and L. angustifolia EOs suggest that they could also help prevent secondary infections.

Characterization and Cytotoxic Evaluation of Silver and Gold Nanoparticles Produced with Aqueous Extract of Lavandula dentata L. in Relation to K-562 Cell Line

Abstract Metallic nanoparticles have great potential as a chemotherapeutic agent. The aim of this study was to develop and characterize silver and gold nanoparticles using a simple method, as well as evaluating the potential cytotoxic activity in relation to the K-562 cell line. For the synthesis, a solution containing the metallic ions was subjected to magnetic stirring with the aqueous extract of Lavandula dentata L. and a change of colour was observed. With the data obtained from the analyses we concluded that the nanoparticles were successfully obtained by a simple and green method using the aqueous extract of L. dentata. The obtained nanoparticles presented a reduced size, a low level of polydispersion, and a homogenous spherical shape. The nanoparticles presented intense and characteristic diffraction peaks, which could be correlated to the planes of the centred cubic structure of the silver and gold. The two formulations presented predominantly crystalline characteristics. The infrared analysis suggested that the amides and alcohols present in the samples may have been responsible for the reduction and limitation of the size and dispersion of the silver and gold nanoparticles. The cytotoxic assay showed that the nanoparticles demonstrated great potential to reduce the cell viability of the K-562 cell line, especially the gold nanoparticles.

In vitro effects of two major phenolic compounds from the family Lamiaceae plants on the human gastric carcinoma cells.

Phenolic compounds of essential oils from the family Lamiaceae are commonly used substances in the food industry because of their flavouring, antimicrobial and antioxidant properties. In this context, it has become important to have healthy and safe products for consumers who are exposed to these phenolic compounds. The present study was aimed to investigate the toxic effects of carvacrol, thymol and their mixture on human gastric carcinoma (AGS) cells. Cells were analyzed after 24 h of exposure to different concentrations of carvacrol, thymol and their mixture by the ATP cell viability, 2',7' dichlorodihydrofluorescein diacetate (H2DCF-DA), reducte glutatione/oxide glutathione ((GSH)/GSSG-Glo) and comet assays. Apoptosis induction was studied by acridine orange/ethidium bromide staining and western blotting. Carvacrol, thymol and their mixture induced cytotoxicity, genotoxicity, apoptosis, increased reactive oxygen species (ROS) and decreased GSH levels after 24 h of their exposure in a dose-dependent manner. A close negative relationship was found between cell viability and ROS generation. We examined dose-dependent cytotoxic effects of carvacrol, thymol and their mixture in human AGS cells. Increased intracellular ROS causes oxidative stress in cells. The results indicated that these compounds should be used carefully in the food industry.

Enzyme inhibitory, Antifungal, Antibacterial and hemolytic potential of various fractions of Colebrookia oppositifolia.

The purpose of the present investigation was to assess the enzyme inhibition, antifungal, antibacterial and hemolytic activities of various fractions of Colebrookia oppositifolia Smith. The MeOH extract of plant was dissolved in dist. water and partitioned with n-hexane, CHCl3, EtOAc and n-BuOH sequentially. Enzyme inhibition studies were done against four enzymes i.e. α-glucosidase, butyrylcholinesterase, acetyl cholinesterase and lipoxygenase. Ethyl acetate fraction possessed very good activity against α-glucosidase (IC50 57.38±1.23µg/mL). CHCl3 fraction displayed good activity against α-glucosidase and lipoxygenase while moderate activity against butyryl cholinesterase. EtOAc fraction displayed good activity against lipoxygenase. Antifungal activity was studied against four fungi i.e. Aspergillus niger, Aspergillus flavus, Ganoderma lucidum and Alternaria alternata by the disc diffusion method using fluconazole, a standard antifungal drug, as positive control. Aqueous fraction displayed good activity against G. lucidum and A. flavus. Antibacterial activity was checked against Staphylococcus aureus, Bacillus subtilis, Pasturella multocida and Escherichia coli by the disc diffusion method using streptomycin sulphate, a standard antibiotic, as positive control. Chloroform, ethyl acetate and aqueous fraction showed good activity against E. coli. Chloroform fraction showed good activity against B. subtilis. Ethyl acetate fraction showed good activity against the P. multocida. All the studied fractions showed very less toxicity i.e. < 7%.

HPLC quantification of coumarin in bastard balm (Melittis melissophyllum L., Lamiaceae).

Coumarin occurs in many plants used as flavoring and is known to possess hepatotoxic effects. Despite in the EFSA 'Compendium of botanicals containing toxic substances' coumarin is reported to be present in Melittis melissophyllum (bastard balm), a plant traditionally used as beverage in Italy and Serbia, to the best of our knowledge quantitative data has never been reported. Thus, the amount of coumarin in bastard balm leaves and its variation during the annual phenological cycle were determined. The subsp. melissophyllum resulted to contain high levels of coumarin (14,392 mg/kg), mainly in the early stages of the plant cycle, suggesting prudence in its use as beverage. Furthermore, coumarin was found to be useful as marker compound to differentiate the bastard balm subspecies occurring in Italy, since the subsp. albida contained a much lower content of this molecule (19-34 mg/kg).

In vitro antiprotozoal activity of extracts of five Turkish Lamiaceae species.

The in vitro antiprotozoal activities of crude methanolic extracts from the aerial parts of five Lamiaceae plants (Salvia tomentosa, S. sclarea, S. dichroantha, Nepeta nuda subsp. nuda and Marrubium astracanicum subsp. macrodon) were evaluated against four parasitic protozoa, i.e. Trypanosoma brucei rhodesiense, T. cruzi, Leishmania donovani and Plasmodium falciparum. The cytotoxic potentials of the extracts on L6 cells were also evaluated. Melarsoprol, benznidazole, miltefosine, chloroquine and podophyllotoxin were used as reference drugs. All crude MeOH extracts showed antiprotozoal potential against at least three parasites, so they were dispersed in water and partitioned against n-hexane and chloroform to yield three subextracts that were screened in the same test systems. The n-hexane extract of N. nuda was the most active against T. brucei rhodesiense while the CHCl3 extracts of S. tomentosa and S. dichroantha showed significant activity against L. donovani. All organic extracts displayed in vitro antimalarial and moderate trypanocidal activities against T. cruzi with the n-hexane extract of S. sclarea being the most active against the latter. The extracts displayed low or no cytotoxicity towards mammalian L6 cells.

Isolation and phytotoxicity of terpenes from Tectona grandis.

A study was carried out on the allelopathic potential of four forest species, Tectona grandis, Aleurites fordii, Gliricidia sepium, and Maytenus buxifolia. The most active species, T. grandis, was selected to perform a phytochemical study. A new compound, abeograndinoic acid, was isolated, and elucidation of its structure showed that this compound has an unusual carbon skeleton. A further 21 known terpenoids-including 4 sesquiterpenoids, 8 diterpenes and 9 triterpenes-also were isolated. A biosynthetic scheme for the presence of the new compound is proposed. Bioactivity profiles that used etiolated wheat coleoptiles and phytotoxicity bioassays on the isolated compounds were conducted. The compounds that presented the highest phytotoxic activity are the diterpenes 9 (2-oxokovalenic acid) and 12 (19-hydroxyferruginol).

Comparison of the nutritional value and biological activities of the acetone, methanol and water extracts of the leaves of Solanum nigrum and Leonotis leonorus.

The nutritional, phytochemical, antioxidant and antibacterial activities of the acetone, methanol and water extracts of the leaves of Solanum nigrum and Leonotis leonorus were investigated using standard analytical methods in order to assess the numerous potential of the leaves of these plants. The proximate analysis showed the that the leaves of the two plants were rich in moisture content, ash content, crude protein, crude lipid, crude fibre and carbohydrate. Elemental analysis in mg/100g (DW) indicated that the leaves contained sodium, potassium, calcium, magnesium, iron, zinc, phosphorus, copper, manganese, and nitrogen. The chemical composition in mg/100g (DW) for alkaloid, saponins, and phytate were moderate. The plants were also rich in polyphenols and had good antioxidant activities. The different extracts of the plants had activities against some of the organisms used in this study. Comparing the nutrient and chemical constituents with recommended dietary allowance (RDA) values, the results reveal that the leaves contain an appreciable amount of nutrients, minerals, and phytochemicals and low levels of toxicants.

Study of embryotoxicity of Perovskia abrotanoides, an adulterant in folk-medicine, during organogenesis in mice.

AIM OF THE STUDY: Perovskia abrotanoides is a medicinal herb which traditionally has been used as a topical application to treat leishmaniasis in Iran. Due to similarities of the flowers of Perovskia abrotanoides and Echium species, it is added as an adulterant to Echium preparations in Iran. Echium flowers have been used in Iranian traditional medicine as an "anti-stress", tranquilizer, and energizer drink, fighting common cold and bronchitis particularly during pregnancy. In this study, the in vivo embryotoxicity of 0.125 and 0.25 g/kg of ethanolic and aqueous extracts of Perovskia abrotanoides during organogenesis in mice has been investigated. MATERIALS AND METHODS: Maternal body weights were recorded and pregnant females were observed daily throughout gestation. After cesarean section, fetuses were weighed, lengthed and examined for gross external malformations. Others were fixed then stained with Alcian blue and Alizarin red to view any skeletal malformations. RESULTS: Our results indicated that this herb causes minimal maternal toxicity, while resorption, stillborn, fetal malformations including polydactyly, spina bifida, aglossia, tarsal extensor, gastroschisis, and numerous skeletal abnormalities were detected particularly in the ethanolic extract groups. Specific skeletal abnormalities based on type of extract were also observed. CONCLUSIONS: Since Perovskia abrotanoides is widely used in traditional medicine intentionally or inadvertently, it is advisable its use during pregnancy should be avoided and strict regulations are imposed to prevent its addition to commercial preparations of other herbal products.

Safety evaluation of the aqueous extract of Leonotis leonurus shoots in rats.

The aqueous extract from Leonotis leonurus (L) R.Br. (Lamiaceae) shoots was evaluated in female rats for its acute, sub acute, and chronic toxicity together with hematological, biochemical, and histopathological changes. In the acute toxicity test, the extract caused death in animals receiving 3200 mg/kg dose. The extract also caused significant (P < 0.05) changes in red blood cells, packed cell volume, hemoglobin concentration, mean corpuscular volume, platelets, white blood cells and its differentials at doses of 1600 mg/kg in sub-acute toxicity and in as low as 200 mg/kg in chronic toxicity. In biochemical parameters, the extract caused a significant (P < 0.05) decrease in the levels of urea and creatinine at 1600 mg/kg dose and a significant (P < 0.05) reduction in urea, total bilirubin, total protein, albumin, globulin, glutamine transference gamma-glutamyl transferase (GGT), and alanine transminase in the 400 mg/kg dose in chronic toxicity. Changes were also noted in body weights, but no significant changes were observed in the levels of electrolytes (sodium, potassium, and chloride). Clinico-pathologically, starry hair coat, respiratory distress, and mortality were recorded. The extract also caused various histopathological changes in the organs. The study concluded that farmers need to exercise caution in the use of the plant for medicinal purposes.

Especies medicinales y tóxicas del género Lepechinia Willd. (Labiatae) en Venezuela / No disponible

Las especies medicinales y tóxicas del género Lepechinia Willd. en Venezuela son Lepechinia bullata (Kunth) Epling y Lepechinia schiedeana (Schleghtd) Vatke, las dos viven en alta montaña. Se han encontrado diferencias en la composición del aceite esencial y en el indumento de la hoja

Lepechinia bullata (Kunth) Epling and Lepechinia schideana (Schleghtd) Watke are the medicinal and toxic species of genus WiIld in Venezuela, both live in high mountain and they have some differences in the composition of the essential oil and some differences in the indument of leaves

In vitro screening for antitumour activity of Clinopodium vulgare L. (Lamiaceae) extracts.

Aqueous extract of Clinopodium vulgare L. showed strong antitumour activity when tested in vitro on A2058 (human metastatic melanoma), HEp-2 (epidermoid carcinoma, larynx, human) and L5178Y (mouse lymphoma) cell lines-6 h after treatment disintegration of the nuclei and cell lysis started. Applied at a concentration of 80 microg/ml it reduced the cell survival to 1.0, 5.6 and 6.6%, respectively. The concentrations of aqueous extract inhibiting the growth of A2058, HEp-2 and L5178Y cells by 50% (IC50 values) were calculated to be 20, 10 and 17.8 microg/ml respectively. Two groups of active substances were detected: the first one, probably combining glycosides, influenced adhesion, while the second one caused massive cell vacuolisation. The chloroform extract, which contained ursolic acid and gentriacontan had also cytotoxic, however a little bit weaker effect. All changes observed were irreversible.

Allied studies on the effect of Rosmarinus officinalis L. on experimental hepatotoxicity and mutagenesis.

The hepatoprotective and antimutagenic effects of the rosemary essential oil and the ethanolic extract were investigated using carbon tetrachloride and cyclophosphamide as hepatotoxic and mutagenic compounds, respectively. Our results revealed that i.g. administration of the rosemary ethanolic extract (0.15 g/100 g BW) to rats for 3 weeks produced the most pronounced hepatoprotective effect compared to silymarin (reference compound) due to the amelioration of most of the studied serum and liver parameters and confirmed by histopathological examination of the liver tissue. Pretreatment of mice for 7 days with the rosemary essential oil (1.1 mg/g BW) followed by i.p. injection with cyclophosphamide reduced significantly the induced mitodepression in the bone marrow cells of the animals. The potential hepatoprotective and antimutagenic activities of the rosemary ethanolic extract and essential oil, respectively, are attributed to the presence of a relatively high percentage of phenolic compounds with high antioxidant activity (according to our chemical studies).