Atividade moduladora de extratos etanólico e hexânico de raiz de Costus cf. arabicus sobre drogas antimicrobianas

The bacterium Escherichia coli is known to produce enterotoxins causing diarrheal diseases. Some species of Staphylococcus are recognized as etiological agents of many animal and human opportunistic infections. Pseudomonas aeruginosa is the main cause of nosocomial infections, mainly affecting immunocompromised patients. Candidiasis is the most frequent opportunistic mycosis, frequently caused by Candida albicans, C. tropicalis, C. parapsilosis, C. glabrata, and C. krusei. Medicinal plants have been the source of many remedies used in the clinical practice. In this study, the hexane and methanol extracts of Costus cf. arabicus were assayed to the antibacterial activity alone or associated with aminoglycosides and antifungal drugs. Synergism of the ethanol and hexane were verified by the microdilution method. A synergistic effect of the two extracts combined with the aminoglycosides and antifungal agents was demonstrated. It is therefore suggested that the extracts from Costus cf. arabicus could be used as a source of natural products with resistance-modifying antimicrobial activity, providing a new mechanism against the problem of bacterial and fungal resistance to drugs.A bactéria Escherichia coli é conhecida por produzir enterotoxinas capazes de causar diarréia. Algumas espécies de Staphylococcus são agentes etiológicos de muitas infecções oportunistas em animais e humanos. Pseudomonas aeruginosa é a principal causa de infecções hospitalares, acometendo principalmente pacientes imunocomprometidos. Candidíase é a micose oportunista mais comum, muitas vezes causada por Candida albicans, C. tropicalis, C. parapsilosis, C. glabrata e C. krusei. As plantas medicinais têm sido a fonte de muitos remédios tradicionais aplicados na prática clínica. Neste trabalho, os extratos hexânico e etanólico de Costus cf. arabicus foram testados quanto a sua atividade antibacteriana de forma isolada e em combinação com aminoglicosídeos e antifúngicos. O sinergismo dos extratos etanólico e hexânico foi verificado pelo método de microdiluição. Foi observado um efeito sinérgico de ambos os extratos quando combinados com os aminoglicosideos e antifúngicos. Sugere-se, portanto, que os extratos de Costus cf. arabicus poderiam ser usados como uma fonte de produtos naturais com atividade modificadora de resistência a drogas antimicrobianas, fornecendo um novo mecanismo contra o problema da resistência bacteriana e fúngica a drogas

The genus Cordia: botanists, ethno, chemical and pharmacological aspects

ABSTRACTSpecies of the genus Cordia, Boraginaceae, are widely studied with regard to the various ethnobotanical and ethnopharmacological aspects. They are found principally in tropical and subtropical regions of the American, Asian and African continents, where they occur in various countries. In the genus Cordia, there are many species cultivated for ornamental plants, wood and medicinal applications, where they are extensively utilized by traditional communities. In the last decades, scientific studies of Cordia species have intensified, demonstrating the great interest in phytochemical, biological and pharmacological studies. In this review, we describe the principal botanical aspects, ethnopharmacological information and evaluation of the bioactive and pharmacological properties of Cordia, its phytochemical constituents and the most common classes of secondary metabolites identified. The information reported in this work contributes scientifically to recognizing the importance of the genus Cordia as a target in the search for new biotechnological investments

Ethnobotanical uses and phytochemical, biological, and toxicological profiles of Datura metel L.: A review

Datura metel L., a recognized poisonous plant in the Solanaceae family, is widely distributed in the world. Traditionally, D. metel is used in many diseases, including neurological and heart diseases; fever; catarrh; pain; diarrhea; skin diseases; chronic bronchitis; asthma; digestive disorders; and so on. It possesses many important phytochemicals that can be used to treat various types of diseases. This review aims at summarizing the traditional uses, phytochemical, biological, and toxicological profiles of D. metel based on the database reports. For this, an up-to-date (till March 20, 2023) search was made in the databases: PubMed, Google Scholar, Science Direct, Scopus, and MedLine, with relevant keywords for the published evidence. Findings suggest that the plant has many traditional uses, such as a cure for madness, epilepsy, psoriasis, heart diseases, diarrhea, mad dog bites, indigestion, etc. It possesses various important phytochemicals, including withanolides, daturaolone, datumetine, daturglycosides, ophiobolin A, baimantuoluoline A, and many others. D. metel has many important biological activities, including antioxidant, anti-inflammatory, anti-microbial, insecticidal, anti-cancer, anti-diabetic, analgesic, anti-pyretic, neurological, contraceptive, and wound healing capacity. In conclusion, the toxic plant, D. metel, can be considered a potential source of phyto-therapeutic lead compounds

Chemical Profile, Antibacterial Activity and Antibiotic-Modulating Effect of the Hexanic Zea Mays L. Silk Extract (Poaceae)

The present study aimed to determine the chemical profile and to evaluate the antibacterial activity and antibiotic-modulating action of the hexanic Zea mays silk extract in association with aminoglycosides. Standard Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853 strains, as well as multi-resistant Escherichia coli 27, Staphylococcus aureus 35, and Pseudomonas aeruginosa 31 strains, were used in this study. Phytochemical prospection revealed the presence of the following secondary metabolites: tannins, flavones, flavonoids, and xanthones, with the main chemical constituents being identified in plant extracts obtained with apolar organic solvents such as hexane. The extract presented a minimum inhibitory concentration (MIC) ≥1024 μg/mL against all the tested strains. The association of the extract with aminoglycoside antibiotics showed significant synergistic effects against Staphylococcus aureus and Pseudomonas aeruginosa, except for amikacin, which was antagonized by the extract against E. coli. These results indicate the Zea mays silk presents bioactive compounds with antibiotic-modulating properties. However, further research is required to characterize the effects of isolated compounds and determine their potential for drug development

GC-MS Chemical Characterization and Antibacterial Effect of the Essential oil of <i>Piper mosenii</i>

Commercialized mouthwashes are generally expensive for the most financially vulnerable populations. Thus, several studies evaluate the antimicrobial potential of herbal products, such as essential oils, to reduce the activity of microorganisms in the mouth. The objective of this research was to carry out the chemical characterization and antibacterial activity of the essential oil of Piper mosenii (EOPm), providing data that enable the development of a low-cost mouthwash formulation aimed at vulnerable communities. The analysis of the antibacterial potential and modulator of bacterial resistance was verified by the microdilution method to determine the minimum inhibitory concentration-MIC. The chemical components were characterized by gas chromatography coupled to mass spectrometry, where 23 chemical constituents were detected, with α-pinene, being the major compound. The EOPm showed a MIC ≥ 1024 µg/mL for all bacterial strains used in the tests. When the EOPm modulating activity was evaluated together with chlorhexidine, mouthwash and antibiotics against bacterial resistance, the oil showed a significant synergistic effect, reducing the MIC of the products tested in combination, in percentages between 20.6% to 96.3%. Therefore, it is recommended to expand the tests with greater variation of EOPm concentration and the products used in this research, in addition to the evaluation of toxicity and in vivo tests, seeking the development of a possible formulation of mouthwash accessible to the vulnerable population