Wild thyme (Thymus serpyllum L.): a review of the current evidence of nutritional and preventive health benefits.

Thymus serpyllum L. (Lamiaceae), known in English as 'wild thyme', is primarily found in the Palearctic realm (Eurasia, North Africa) and has been utilized traditionally for culinary, nutritional, medicinal, and aromatic purposes. The essential oil extracted from wild thyme is particularly noteworthy, being used extensively in the food industry as a flavoring agent and preservative. The plant's aerial parts are commonly employed as an element of the diet (e.g., tea)/for culinary uses and in local/traditional medicine (primarily for managing respiratory and gastrointestinal conditions), similar to the use of common thyme. There is practically no information available on the species' nutritional benefits. Pharmacological studies, including in vitro and in vivo research, alongside a limited number of clinical trials, have investigated extracts of Thymus serpyllum, although these extracts are often phytochemically poorly characterized in different experimental protocols and models. These studies have demonstrated a range of therapeutic effects, such as antimicrobial (notably the essential oil) and anti-inflammatory, as well as its preventative health benefits and nutritional value of wild thyme. Preclinical studies have corroborated the plant's anti-inflammatory potential, particularly in conditions like inflammatory bowel diseases (IBD) and irritable bowel syndromes (IBS). Additionally, evidence of hepatoprotective activities and benefits in managing metabolic syndrome and cardiovascular health issues, such as lipid metabolism regulation, cholesterol reduction, antidiabetic, antihypertensive, and immunomodulatory effects, have been observed predominantly in rodent models. Phytochemical analysis of wild thyme reveals an essential oil fraction below 1%, along with non-volatile compounds predominantly comprising phenolic acids (such as rosmarinic, salvianolic, and caffeic acids) and flavonoids (mainly glucosides of luteolin, apigenin, and their derivatives). These components are believed to contribute significantly to the plant's medicinal, nutritional, and preventive health properties. Despite promising findings, there is a need for more rigorously designed controlled clinical trials using phytochemically characterized wild thyme. The plant has an excellent safety and tolerability record. This review at the interface of nutritional/preventive health properties and as pharmacological activities highlights the current role of wild thyme in nutrition and general healthcare as well as its future potential, and also points to important gaps in the literature.

Pharmacognostic evaluation, and development and validation of a HPLC-DAD technique for gallocatechin and epigallocatechin in rhizomes from Limonium brasiliense

ABSTRACT Limonium brasiliense (Boiss.) Kuntze, Plumbaginaceae, is a plant from the southern coast of Brazilian that is used for the treatment of premenstrual syndrome, menstrual disorders and genito-urinary infections. The aim of the present study was to determine the quality control parameters for rhizomes collected during different periods by pharmacopoeial and non-pharmacopoeial methods, and to develop and validate a HPLC-DAD method for quantitative control of marker substances. The measured parameters were: granulometric analysis (d50 = 0.21–0.48 mm), loss on drying (11.1–12.4%), total ash (4.9–5.7%), dry residue by extraction with acetone:water (7:3, v/v) (30.6–39.5%), total polyphenol content (8.5–15.8%), and chromatographic fingerprint by HPLC and TLC. Besides, the acetone:water (7:3, v/v) extraction solvent in combination with a turbo-extractor, yielded the crude extract with a significant increase in tannins (F4,20 = 37.0, p < 0.001). The antioxidant potential of the crude acetone:water (7:3, v/v) extract, as well as the ethyl acetate and water fractions obtained after the partition process was evaluated by DPPH and the results were, respectively: IC50 6.87, 5.91, and 6.92 µg/ml. The validation parameters for the HPLC-DAD method showed adequate specificity, precision and accuracy. The gallo- and epigallocatechin contents were, respectively, 0.8–2.7% and 1.2–2.2%. These data contribute to analysis of the pharmacognostic quality control of the commonly used part from this species.

Antibacterial activity of Limonium brasiliense (Baicuru) against multidrug-resistant bacteria using a statistical mixture design.

ETHNOPHARMACOLOGICAL RELEVANCE: Limonium brasiliense (Boiss.) Kuntze (Plumbaginaceae) is commonly known as "baicuru" or "guaicuru" and preparations of its dried rhizomes have been popularly used in the treatment of premenstrual syndrome and menstrual disorder, and as an antiseptic in genito-urinary infections. This study evaluated the potential antibacterial activity of rhizome extracts against multidrug-resistant bacterial strains using statistical mixture design. MATERIALS AND METHODS: The statistical design of four components (water, methanol, acetone, and ethanol) produced 15 different extracts and also a confirmatory experiment, which was performed using water:acetone (3:7, v/v). The crude extracts and their ethyl-acetate fractions were tested against vancomycin-resistant Enterococcus faecium (VREfm), methicillin-resistant Staphylococcus aureus (MRSA) and Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae, all of which have been implicated in hospital and community-acquired infections. The dry residue, total polyphenol, gallocatechin and epigallocatechin contents of the extracts were also tested and statistical analysis was applied in order to define the fit models to predict the result of each parameter for any mixture of components. The principal component and hierarchical clustering analyses (PCA and HCA) of chromatographic data, as well as mass spectrometry (MS) analysis were performanced to determine the main compounds present in the extracts. RESULTS: The Gram-positive bacteria were susceptible to inhibition of bacterial growth, in special the ethyl-acetate fraction of ternary extracts from water:acetone:ethanol and methanol:acetone:ethanol against, respectively, VREfm (MIC=19µg/mL) and MRSA (MIC=39µg/mL). On the other hand, moderate activity of the ethyl-acetate fractions from primary (except water), secondary and ternary extracts (MIC=625µg/mL) was noted against KPC. The quadratic and special cubic models were significant for polyphenols and gallocatechin contents, respectively. Fit models to dry residue and epigallocatechin contents were not possible. PCA and HCA of the chromatographic fingerprints were disturbed by displacement retention time of some peaks, but the ultraviolet spectra indicated the homogeneous presence of flavan-3-ols characteristic of tannins. The MS confirmed the presence of gallic acid, gallocatechin, and epigallocatechin in extracts, and suggested the presence of monomers and dimers of B- and A-type prodelphinidins gallate, as well as a methyl gallate. CONCLUSION: Our results showed the antibacterial potential of L. brasiliense extracts against multidrug-resistant Gram-positive bacteria, such as VREfm and MRSA. The statistical design was a important tool to evaluate the biological activity by optimized form. The presence of some phenolic compounds was also demonstrated in extracts.

Acute toxicity and long-term safety evaluation of the crude extract from rhizomes of Limonium brasiliense in mice and rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Limonium brasiliense (Boiss.) Kuntze, Plumbaginaceae, popularly known as baicuru, has been used in folk medicine to treat menstrual cramps and to regulate menstrual periods. However, little is known about its safety. This study evaluated the safety through in vivo tests of the acute, long-term, and liver toxicity, and the mutagenicity of the crude extract (CE) from rhizomes of L. brasiliense. MATERIALS AND METHODS: The acute toxicity was assessed in Swiss mice, and the chronic toxicity in Wistar rats. Male and female mice received the CE orally in single doses of 1.0, 2.0, 3.0, 4.0, or 5.0 g/kg. Clinical changes and mortality rate were used as parameters to assess the acute toxicity. In the long-term evaluation, male and female Wistar rats were treated orally with daily doses of the CE (50, 100, or 200 mg/kg) for 90 days. Assessments of weight, behavior and food intake, urinalysis, biochemical and hematological analyses, as well as macro- and microscopic observations of several organs were performed. The redox state of the liver was evaluated as a means of investigating the liver toxicity, and the micronucleus test to assess mutagenicity was also performed. RESULTS: Evaluation of acute toxicity indicated no apparent clinical change in the animals; the LD50 was 4.8 g/kg. Evaluation after 90 days administration showed that the CE, even in higher doses than are considered therapeutic, appeared to be safe. The micronucleus test demonstrated a low mutagenic potential for the CE. CONCLUSION: Our results showed that treatment with the CE from L. brasiliense caused low or no toxicity, as assessed using these doses and evaluation methods.

Morpho-anatomical study of rhizome of Limonium brasiliense

AbstractLimonium brasiliense (Boiss.) Kuntze, Plumbaginaceae, is an herb popularly known as guaicuru, guaicurá or baicuru. The species inhabits salt marshes from the coastal region of southern Brazil, including Rio de Janeiro, to Uruguay and Argentina. Although widely used in folk medicine in the state of Rio Grande do Sul to treat genitourinary infections and to regulate menstrual periods, L. brasiliense has been little studied. The present morpho-anatomical study was undertaken to resolve some doubts in the literature as to the nature of the part of the plant that is used for medicinal purposes, a true rhizome or a root. The morpho-anatomical characteristics were analyzed with the aid of light and scanning electron microscopy. The botanical material was characterized as a rhizome with internodes that are evident in the younger but not the older portions. Microscopic analysis revealed the presence of a multilayered periderm with a cortex, ray parenchyma, and pith, formed by collenchyma tissue with abundant intercellular spaces in the outer portions of the cortex, responsible for the rigidity of the body, and with walls impregnated with phenolic compounds. The vascular bundles are collateral with elliptical to elongated cells, and with few conducting and sclerenchymal elements. Groups of sclereids are dispersed through the cortex and pith. These morpho-anatomical characteristics define the structure as a rhizome.

Application and analysis of the folin ciocalteu method for the determination of the total phenolic content from Limonium brasiliense L.

Limonium brasiliense is a common plant on the southern coast of Brazil. The roots are traditionally used for treatment of premenstrual syndrome, menstrual disturbances and genito-urinary infections. Pharmaceutical preparations obtained from its roots and used for these purposes were marketed in Brazil in the 1980s and 1990s. Currently, the Brazilian Drug Agency (National Health Surveillance Agency, ANVISA) has canceled the registration of these products, and their use was discontinued because of a lack of studies to characterize the plant raw material and ensure the effectiveness and safety of its use. The aim of the present study was to develop and validate an analytical method to determine the content of total polyphenols (TP) in an extract from L. brasiliense roots, by the UV/Vis spectrophotometric method. L. brasiliense roots were extracted in acetone:water (7:3, v/v-10% w/v). The crude extract was used to develop a method for TP assay. The method was validated according to national and international guidelines. The optimum conditions for analysis time, wavelength, and standard substance were 30 min, 760 nm, and pyrogallol, respectively. Under these conditions, validation by UV/Vis spectrophotometry proved the method to be linear, specific, precise, accurate, reproducible, robust, and easy to perform. This methodology complies with the requirements for analytical application and to ensure the reliability of the results.

Development and validation of an HPLC method for the determination of epicatechin in Maytenus ilicifolia (Schrad.) Planch., Celastraceae / Desenvolvimento e validação de um método de CLAE para a determinação da epicatequina em Maytenus ilicifolia (Schrad.) Planch., Celastraceae

A simple, reproducible and efficient high-performance liquid chromatography (HPLC) method was developed. Water (0.05 percent TFA):acetonitrile (0.05 percent TFA) was used as the mobile phase in a gradient system for the determination of epicatechin (EP) in leaves of Maytenus ilicifolia (Schrad.) Planch. The analysis was performed using an RP C-18 column (5 µm) as the stationary phase, with a flow rate of 0.8 mL/min, at a wavelength of 210 nm for detection and determination. The main validation parameters of the method were also determined. The calibration curve was found to be linear, with a range of 10-120 µg/mL (EP). The correlation coefficient of the linear regression analysis was within 0.9988, and the detection and quantification limits were 28.61 and 86.77 µg/mL, respectively. The content of EP was successfully determined, with satisfactory reproducibility and recovery. Recovery of the EP was 99.32 percent. The method was successfully applied to the determination of epicatechin in leaves of M. ilicifolia. The interlaboratorial evaluation showed the reproducibility of the method with a relative standard deviation of 14.62 percent.

Um método simples, reprodutível e eficiente de cromatografia líquida de alta eficiência (CLAE) foi desenvolvido. Água (0,05 por cento TFA):acetonitrila (0,05 por cento TFA) foi utilizado como fase móvel em um sistema de gradiente para a determinação da epicatequina (EP) em folhas de Maytenus ilicifolia (Schrad.) Planch., Celastraceae. A análise foi realizada utilizando coluna RP C-18 (5 µm) como fase estacionária, com vazão de 0,8 mL/min, e comprimento de onda de 210 nm para a detecção e determinação. Os principais parâmetros de validação do método foram determinados. A curva analítica apresentou-se linear no intervalo de 10-120 µg/mL (EP). O coeficiente de correlação da análise de regressão linear foi de 0,9988, o limite de detecção e o limite de quantificação foram de 28,61 e 86,77 µg/mL, respectivamente. O conteúdo do EP foi determinado com sucesso, com boa reprodutibilidade e recuperação. Recuperação da EP foi 99,32 por cento. O método foi aplicado com sucesso na determinação da epicatequina em folhas de M. ilicifolia. A avaliação interlaboratorial demonstrou a reprodutibilidade do método com desvio padrão relativo de 14,62 por cento.

Dual effects of crude extracts obtained from Petiveria alliacea L. (Phytolaccaceae) on experimental anxiety in mice.

AIM OF THE STUDY: Different preparations obtained from P. alliacea have been traditionally used in South America and Brazil for many medical conditions. To investigate the effects of fresh whole plant (WP) extract, aerial part (AP) extract, and root (R) extract obtained from Petiveria alliacea using the elevated plus maze (EPM) model of anxiety in mice. Total flavonoid content present in Petiveria alliacea extracts was also determined. MATERIALS AND METHODS: WP, AP, or R (300-900 mg/kg) extracts were orally administered to mice 30 min before they were subjected to the EPM and open field test. Total flavonoid content present in the extracts was determined by spectrophotometry. RESULTS: The WP extract (300 and 900 mg/kg) caused anxiolytic-like effects, and the AP extract (300 mg/kg) induced anxiogenic-like effects in mice subjected to the EPM. No effect on anxiety-like behavior was observed with acute administration of the R extract. The content of flavonoids present in the AP extract (1.34%) was almost threefold higher than the flavonoid content present in the WP extract (0.52%). CONCLUSIONS: Preparations using different fresh parts of Petiveria alliacea caused opposite effects on experimental anxiety in mice. However, predicting the extent to which flavonoid content present in Petiveria alliacea extracts differentially induces anxiolysis or anxiogenesis in mice was not possible. Further studies will be necessary to elucidate the effects of flavonoids or other substances present in Petiveria alliacea extracts on experimental anxiety.