The Free Radical Scavenging Property of the Leaves, Branches, and Roots of Mansoa hirsuta DC: In Vitro Assessment, 3D Pharmacophore, and Molecular Docking Study.

In this work, a metabolic profile of Mansoa hirsuta was investigated, and in vitro assays and theoretical approaches were carried out to evaluate its antioxidant potential. The phytochemical screening detected saponins, organic acids, phenols, tannins, flavonoids, and alkaloids in extracts of leaves, branches, and roots. Through LC-MS analysis, the triterpenes oleanolic acid (m/z 455 [M-H]-) and ursolic acid (m/z 455 [M-H]-) were identified as the main bioactive components. The extracts of the leaves, branches, and roots revealed moderate antioxidant potential in the DPPH test and all extracts were more active in the ABTS test. The leaf extracts showed better antioxidant capacity, displaying IC50 values of 43.5 ± 0.14, 63.6 ± 0.54, and 56.1 ± 0.05 µg mL-1 for DPPH, ABTS, and kinetics assays, respectively. The leaf extract showed higher total flavonoid content (TFC) (5.12 ± 1.02 mg QR/g), followed by branches (3.16 ± 0.88 QR/g) and roots (2.04 ± 0.52 QR/g/g). The extract of the branches exhibited higher total phenolic content (TPC) (1.07 ± 0.77 GAE/g), followed by leaves (0.58 ± 0.30 GAE/g) and roots (0.19 ± 0.47 GAE/g). Pharmacophore and molecular docking analysis were performed in order to better understand the potential mechanism of the antioxidant activity of its major metabolites.

One pot green fabrication of metallic silver nanoscale materials using Crescentia cujete L. and assessment of their bactericidal activity.

In this study, the leaf extract of an important medicinal plant Crescentia cujete L. (CC) was employed as a green reducing agent to synthesise highly-stable C. cujete silver nanoparticles (CCAgNPs). The reduction of Ag+ to Ag0 nanoparticles was initially observed by a colour change which generates an intense surface plasmon resonance peak at 417 nm using a UV-Vis spectrophotometer. Various optimisation factors such as temperature, pH, time and the stoichiometric proportion of the reaction mixture were performed, which influence the size, dispersity and synthesis rate of CCAgNPs. In addition, surface chemistry of synthesised CCAgNPs through Fourier transform infrared spectroscopy reveals the reducing/stabilising agent present in the aqueous extract of C. cujete and synthesised CCAgNPs. Transmission electron microscopy analysis features the spherical shape of CCAgNPs with an average size of 39.74 nm. Furthermore, an X-ray diffraction study confirms that the synthesised CCAgNPs were face-centred cubic crystalline in nature. The CCAgNPs display tremendous bactericidal activity against human pathogens Bacillus subtilis, Staphylococcus epidermidis, Rhodococcus rhodochrous, Salmonella typhi, Mycobacterium smegmatis, Shigella flexneri and Vibrio cholerae via penetrating into the bacterial cell membrane and causing failure of an internal chain reaction.

Green synthesis of Stereospermum suaveolens capped silver and gold nanoparticles and assessment of their innate antioxidant, antimicrobial and antiproliferative activities.

Plant-extract mediated nanoparticles synthesis is a viable alternative to chemical reduction techniques. Here, we report the microwave-assisted rapid synthesis of silver and gold nanoparticles by the phytoreducer Stereospermum suaveolens for the first time. The formation of the nascent silver and gold nanoparticles is confirmed by their intense surface plasmon resonance peaks at 431 and 585 nm in UV-visible spectroscopy. The poly phenolic and alcoholic functional groups present in the aqueous root bark extract that performed the bioreduction processes have been detected using Fourier transform infrared spectroscopy. Powder X-ray diffraction and selected area electron diffraction patterns settled face centered cubic crystal structures to both silver and gold nanoparticles with a preferred orientation towards the (111) plane. Transmission electron microscopic analysis proved more or less spherical geometry of the silver and gold nanoparticles with average diameter of 49.77 ± 11.64 and 27.19 ± 5.96 nm, respectively. The nanoparticles showed excellent free-radical scavenging activity than the root bark extract Stereospermum suaveolens and the IC50 values obtained were 108.36 ± 1.62, 45.59 ± 0.18, 34.53 ± 0.31 µg/mL, respectively, for the extract, gold and silver nanoparticles. The metal nanoparticles have accomplished good antimicrobial properties towards bacterial and fungal pathogens and were demonstrated herein. The antiproliferative effects of the synthesized silver and gold nanoparticles on human lung adenocarcinoma cells A549 were studied using the MTT assay and the obtained IC50 values 33.81 ± 0.72 and 52.97 ± 0.73 µg/mL lies in the clinical range.

In vitro toxicological assessment of Arrabidaea brachypoda (DC.) Bureau: Mutagenicity and estrogenicity studies.

Arrabidaea brachypoda (DC.) Bureau is a shrub native Cerrado, known as "cipó-una", "tintureiro" or "cervejinha do campo" and popularly used in Southeastern and Northeastern Brazil to treatment of kidney stones and painful joints (arthritis). Nevertheless, scientific information regarding this species is scarce, and there are no reports related to its possible estrogenic and mutagenic effects. Thus, the principal objective of this study was to assess the mutagenic and estrogenic activities of the hydroalcoholic extracts of the leaves, stalks, roots, their respective fractions and isolated compounds of A. brachypoda. The mutagenic activity was evaluated by the Ames test on Salmonella typhimurium strains TA98, TA97a, TA100 and TA102, in the absence (-S9) and presence (+S9) of metabolic activation system. In the RYA was used Saccharomyces cerevisiae engineered strain BY4741 (MATaura3Δ0 leu2Δ0 his3Δ1 met15Δ0) which reproduce the natural pathway of genetic control by estrogens in vertebrate cells; it has the advantage of its simplicity and a high throughput. All extracts and aqueous fraction of leaves A. brachypoda were mutagenic. The crude extract is more active than the fraction, suggesting a synergic effect. Only hydroalcoholic extracts of leaves and roots of A. brachypoda showed significant estrogenic activity, with ERα-dependent transcriptional activation activity. The obtained results in this study showed the presence of compounds capable of interacting with the estrogen receptor and to induce damage in the genetic material. Thus, we demonstrated the risk which the population is subjected due to indiscriminate use of extracts without detailed study.

Avaliação do potencial biológico da Tabebuia aurea (Silva Manso) como fonte de moléculas bioativas para atividade antimicrobiana, antiedematogênica e antirradicalar / Biological potential assessment of Tabebuiaaurea (Silva Manso) as a source of bioactive molecules for antimicrobial, antiedematogenic and antiradical activity

RESUMO As espécies da família Bignoniaceae e do gênero Tabebuia são amplamente utilizadas na medicina tradicional e possuem um forte potencial terapêutico. Diante disso, objetivou-se avaliar o potencial biológico da Tabebuia aurea, determinando a atividade antimicrobiana; por meio do método da microdiluição em caldo, para a determinação da Concentração Inibitória Mínima (CIM); antiedematogênica, pelo ensaio de edema de orelha induzido por capsaicina; e antirradicalar, frente ao radical DPPH. Os extratos etanólicos de T. aurea não evidenciaram citotoxicidade, exceto o extrato etanólico da flor nas concentrações > 0,5 mg mL-1. O extrato etanólico da flor foi ativo com ação bactericida frente a S. epidermidis (CIM de 0,06 mg mL-1) enquanto o extrato etanólico da folha foi moderadamente ativo frente a S. epidermidis (CIM: 0,25 mg mL-1) e S. aureus (CIM: 0,50 mg mL-1) sugerindo ação bacteriostática para ambas as linhagens. Os dois extratos apresentaram ação antiedematogênica, com inibição do edema de 40,50% pelo extrato etanólico da flor e de 41,73% pelo extrato da folha. T. aurea não apresentou atividade antirradicalar. Os resultados comprovam o perfil antibacteriano e antiedematogênico com ausência de citotoxidade pela T. aurea. Sugere-se a continuação dos testes com frações e substâncias isoladas das flores e folhas da referida espécie vegetal, bem como de experimentos in vivo, como forma de agregar evidências visando à busca de novos fitoterápicos.

ABSTRACT The species of Bignoniaceae family and genus Tabebuia are widely used in the traditional medicine and have a great therapeutic potential. The aim of the current research was to evaluate the biological potential of the Tabebuia aurea, determining its antimicrobial activity by the microdilution broth method, to predict the anti-edematogenic Minimum Inhibitory Concentration (MIC) by ear edema assay induced by capsaicin; and the antiradical one, towards DPPH. The ethanol extracts of T. aureashowed no cytotoxicity, except for the flower ethanol extract in concentrations above > 0.5 mg mL-1. The ethanol extract of the flower was active, with bactericidal action, against S. epidermidis (MIC 0.06 mg ml-1) and the ethanol extract of moderately active recto S. epidermidis (CIM: 0.25 mg mL-1) and S. aureus (MIC: 0.50 mg mL-1) were bacteriostatic for both strains. Both extracts had antiedematogenic action on the inhibition of edema of 40.50% by the ethanol extract of the flower and 41.73% by leaf extract. T. aurea did not show antiradical activity. The results indicate the antibacterial and antiedematogenic profile with no cytotoxicity by the T. aurea. It suggests the continuation of tests with isolated fractions and substances of flowers and leaves of that plant species as well as in vivo trials, in order to enhance the evidences targeted on finding new herbal medicines.

Dimeric flavonoids from Arrabidaea brachypoda and assessment of their anti-Trypanosoma cruzi activity.

The nonpolar fraction of an aqueous ethanol extract of the roots of Arrabidaea brachypoda, a Brazilian medicinal plant, demonstrated significant in vitro activity against Trypanosoma cruzi, the parasite responsible for Chagas disease. Targeted isolation of the active constituents led to the isolation of three new dimeric flavonoids (1-3), and their structures were elucidated using UV, NMR, and HRMS analysis, as well as by chemical derivatization. The anti-T. cruzi activity and cytotoxicity toward mammalian cells were determined for these substances. Compound 1 exhibited no activity toward T. cruzi, while flavonoids 2 and 3 exhibited selective activity against these trypomastigotes. Compounds 2 and 3 inhibited the parasite invasion process and its intracellular development in host cells with similar potencies to benznidazole. In addition, compound 2 reduced the blood parasitemia of T. cruzi-infected mice. This study has revealed that these two dimeric flavonoids represent potential anti-T. cruzi lead compounds for further drug development.

Evolution of disparity between the regular and variant phloem in Bignonieae (Bignoniaceae).

PREMISE OF THE STUDY: The phloem is a plant tissue with a critical role in plant nutrition and signaling. However, little is still known about the evolution of this tissue. In lianas of the Bignoniaceae, two distinct types of phloem coexist: a regular and a variant phloem. The cells associated with these two phloem types are known to be anatomically different; however, it is still unclear what steps were involved in the evolution of such differences. METHODS: Here we studied the anatomical development of the regular and variant phloem in representatives of all 21 genera of Bignonieae and used a phylogenetic framework to investigate the timing of changes associated with the evolution of each phloem type. KEY RESULTS: We found that the variant phloem always appears in a determinate location, between the leaf orthostichies. Furthermore, the variant phloem was mostly occupied by very wide sieve tubes and generally included a higher concentration of fibers, indicating an increase in conduction and mechanical support. On the other hand, the regular phloem included much more parenchyma, more and wider rays, and tiny sieve tubes that resembled terminal sieve tubes from plants with seasonal formation of vascular tissues; these findings suggest reduced conduction and higher storage capacity in the regular phloem. CONCLUSIONS: Overall, differences between the regular and variant phloem increased over time, leading to further specialization in conduction in the variant phloem and an increase in storage specialization in the regular phloem.