Antitumor effect of depsidones from lichens on tumor cell lines and experimental murine melanoma

Abstract Lichens have exhibited numerous biological activities, including growth inhibition of tumor cells. This study evaluated the antiproliferative activity of hypostictic and salazinic acids against tumor cell lines (B16-F10, PC-03, MCF7, HT-29, HEP-G2, K562 and 786-0) by the SRB assay in vitro and antitumor activity in experimental murine melanoma in vivo. Activation of caspase-3 was quantified by flow cytometry. The murine experimental melanoma model B16-F10 was used in BALB/c mice for evaluation of antitumor activity. Hypostictic acid showed significant antiproliferative activity in K562 cells (GI50 2.20 µM), B16-F10 (GI50 13.78 µM) and 786-0 (GI50 14.24 µM), whereas salazinic acid was more active against K562 cells (GI50 64.36 µM), HT-29 (GI50 67.91 µM) and B16-F10 (GI5078.64 µM). Quantification of capase-3 revealed that the test compounds did not increase the expression of that enzyme. In the in vivo antitumor evaluation in B16-F10 melanoma, the isolated compounds inhibited tumor growth in relation to weight and volume. Hypostictic acid (16.7 mg/kg) inhibited 72% and salazinic acid 88% of tumor volume (p < 0.05). The results indicated that, both in the in vitro and in vivo models, the compounds evaluated showed antiproliferative and antitumor activities.

Phytotoxicity of Perlatolic Acid and Derivatives

ABSTRACT Perlatolic acid (1), methyl perlatolate (2), and the products of perlatolic acid alcoholysis-namely, methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, and n-hexyl 2-hydroxy-4-methoxy-6-n-pentylbenzoate (3-11)-were evaluated for their herbicidal potential on Lactuca sativa L. (lettuce) and Allium cepa L. (onion) seeds. The compounds exhibited low phytotoxicity on L. sativa germination. Perlatolic acid (1) proved the most active compound (20%). Activity was lowest for n-hexyl 2-hydroxy-4-methoxy-6-n-pentylbenzoate (11) (3.5%). The esters iso-propyl and sec-butyl 2-hydroxy-4-methoxy-6-n-pentylbenzoate (6 and 8, respectively) inhibited root (35% e 43%, respectively) and hypocotyl growth (59% e 56%, respectively). The esters n-butyl, n-pentyl, and n-hexyl 2-hydroxy-4-methoxy-6-n-pentylbenzoate (7, 10, and 11, respectively) proved phytotoxic to A. cepa, delaying and reducing seed germination (27%), while n-pentyl 2-hydroxy-4-methoxy-6-n-pentylbenzoate (10) was the most inhibitory for root (42%) and coleoptile growth (24%). The behaviors of iso-propyl, sec-butyl, and n-pentyl 2-hydroxy-4-methoxy-6-n-pentylbenzoate (6, 8, and 10, respectively) suggest the potential utility of these esters as natural herbicides. The esters iso-propyl and sec-butyl 2-hydroxy-4-methoxy-6-n-pentylbenzoate (6 and 8, respectively) may serve as model molecules in the investigation of potential herbicides for dicotyledon control, while n-pentyl 2-hydroxy-4-methoxy-6-n-pentylbenzoate (10) may serve the same function for monocotyledon species.

Phenolic compounds and antioxidant, antimicrobial and antimycobacterial activities of Serjania erecta Radlk. (Sapindaceae)

Serjania erecta Radlk.(Sapindaceae) is a medicinal plant traditionally used in Brazil. We assayed the ethanolic extract of leaves and roots against seven microorganisms. The REMA (Resazurin Microtiter Assay) assay was used to measure the biological activity in vitro against Mycobacterium tuberculosis and our results showed moderate activity of the ethanolic extract. On the other hand S. aureus, P. aeruginosa, S. setubal, C. albicans, S. cerevisiae and E. coli revealed that the leaves and roots of S. erecta inhibited the growth of all microorganisms. The ethanolic extracts of leaves and roots showed low values of antioxidant activities. The ethanolic extracts of leaves and roots were analyzed by chromatographic and spectrometric methods. (-)-Epicatechin, kaempferol aglycone and five glycoside derivates were isolated: kaempferol-3-O-α-L-rhamnopyranoside, kaempferol-3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside from the roots and kaempferol, kaempferol 3,7-di-O-α-L-rhamnopyranoside, vitexin, isovitexin and (-)-epicatechin in the leaves. This is the first chemical study reported in the literature about this specie.

Serjania erecta Radlk. (Sapindaceae) é uma planta medicinal utilizada no Brasil. Analisamos o extrato etanólico de folhas e raízes para sete microorganismos. O REMA (Ensaio de Microtitulação Resazurina) foi utilizado para medir a atividade biológica in vitro contra o Mycobacterium tuberculosis e nossos resultados mostraram atividade moderada do extrato etanólico. Por outro lado, ensaios com S. aureus, P. aeruginosa, S. setubal, C. albicans, S. cerevisiae e E. coli revelaram que as folhas e raízes de S. erecta inibiram crescimento em todos os microorganismos. Os extratos etanólicos de folhas e raízes apresentaram valores baixos de atividade antioxidante. Os extratos etanólicos de folhas e raízes foram analisados por métodos cromatográficos e espectroscópicos. (-)-Epicatequina, canferol aglicona e cinco derivados glicosídicos foram isolados: canferol -3-O-α-L-ramnopiranosídeo, canferol-3-O-α-L-ramnopiranosil-(1→6)-β-D-glucopiranosídeo a partir das raízes e canferol, canferol 3,7-di-O-α-L-ramnopiranosídeo, vitexina, isovitexina e (-) epicatequina nas folhas. Este é o primeiro estudo químico na literatura sobre esta espécie.

Gas Chromatography-Mass Spectrometry (GC-MS) and evaluation of antioxidant and antimicrobial activities of essential oil of Campomanesia adamantium (Cambess.) O. Berg (Guavira) / Cromatografia Gasosa-Espectrometria de Massas (CG-EM) e avaliação da atividade antioxidante e antimicrobiana do óleo essencial de Campomanesia adamantium (Cambess.) O. Berg (guavira)

The essential oils from Campomanesia adamantium (Cambess.) O. Berg leaves, collected in the reproductive (flowering and fruit-bearing) and vegetative stages, were characterized by GC-MS (Gas Chromatography-Mass Spectrometry). A total of 95 compounds of the essential oils were identified. In the reproductive stage (flowering) the major constituents were monoterpenes (limonene, α-pinene and β-pinene) while during the vegetative stage the major constituents were the sesquiterpenes (bicyclogermacrene and globulol). The essential oil of the reproductive stage shows high antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans, and all show moderate activity against Escherichia coli. The essential oils were also evaluated for their radical-scavenging activity by DPPH. The chemogeographical variations of the oil composition from the four distinct localities studied all contained α-pinene, β-pinene, limonene, linalool, β-caryophyllene, germacrene D and bicyclogermacrene, however the samples from Jardim city contained neither limonene nor linalool.

Os óleos essenciais obtidos das folhas de Campomanesia adamantium foram caracterizados através da combinação de CG-EM e índice de retenção, sendo identificado um total de 95 compostos. Na floração as substâncias majoritárias foram monoterpenos (limoneno, α-pineno e β-pineno) e durante o estágio vegetativo as substâncias majoritárias foram sesquiterpenos (biciclogermacreno e globulol). Os óleos essenciais obtidos da floração e frutificação mostraram alta atividade contra Staphylococcus aureus, Pseudomonas aeruginosa e Candida albicans e moderada contra Escherichia coli em todos os estágios. Foi avaliada a atividade antioxidante dos óleos essenciais usando o método do DPPH. O óleo essencial das 4 cidades mostrou a presença de α-pineno, β-pineno, limoneno, linalol, β-cariofileno, germacreno D e biciclogermacreno, mas a amostra da cidade de Jardim não apresentou limoneno e linalol.

Allelopathic potential of orsellinic acid derivatives

Environmental degradation caused by the excessive use of pesticides has motivated studies aimed at the discovery of new formulations for pest control. The bioassays carried out under laboratory conditions for the present study involved the germination and seedling growth of Lactuca sativa cv. Grand Rapids and Allium cepa cv. Baia Periforme treated with lecanoric acid or one of seven esters obtained from the alcoholysis of the acid. Each substance was tested at concentrations of 10-3, 10-5, 10-7 M, and 10-9 M. The results revealed that, except for lecanoric acid and methyl orsellinate, all other compounds exhibited significant differences in their action when compared with the controls. Also, A. cepa was more sensitive to the compounds assayed, at the concentrations tested. Nearly all the esters exhibited significant effects, a feature that could makes them promising for the development of new natural herbicides.

A degradação do meio ambiente ocasionada pelo uso excessivo de agrotóxicos impulsiona pesquisas que visam a descoberta de novos pesticidas. Os bioensaios conduzidos em condições de laboratório no presente estudo, envolveu a germinação e o crescimento de plântulas de Lactuca sativa cv. Grand Rapids e Allium cepa cv. Baia Periforme tratadas com ácidos lecanórico ou um dos sete ésteres obtidos pela alcoólise deste ácido. Cada substância foi ensaiada nas concentrações 10-3 M, 10-5 M, 10-7 M, e 10-9 M. Os resultados indicaram que exceto o ácido lecanórico e o orselinato de metila, todos os demais apresentaram diferenças significativas em relação ao controle. Além disso, observou-se que A. cepa foi mais sensível aos compostos ensaiados, nas quatro concentrações. Praticamente todos os ésteres avaliados apresentaram efeitos significativos, o que os torna compostos potenciais na descoberta de novos herbicidas naturais.

Avaliação do perfil cromatográfico em espécies de Polygonum e amostras comercializadas como "erva-de-bicho" / Evaluation of the chromatographic profile of species of Polygonum and samples of the "erva-de-bicho"

As espécies Polygonum punctatum, Polygonum hydropiperoides, Polygonum ferrugineum, Polygonum acuminatum foram analisadas quanto ao perfil cromatográfico e comparadas com amostras comercializadas como "erva-de-bicho". As análises foram realizadas empregando cromatografia líquida de alta eficiência. Verificou-se que as amostras analisadas exibem perfil cromatográfico distinto. O perfil cromatográfico das amostras comercializadas como "erva-de-bicho" foram semelhantes aos obtidos para as amostra de Polygonum acuminatum ou Polygonum ferrugineum ou não apresentaram picos nos cromatogramas. Foram monitorados na determinação do perfil cromatográfico os comprimentos de onda de 254 nm e 362 nm.

The species Polygonum punctatum, Polygonum hydropiperoides, Polygonum ferrugineum, Polygonum acuminatum were analyzed and compared with commercialized samples of "erva-de-bicho". This analysis was performed using high performance liquid chromatography. It was verified that the analyzed samples show a distinct. The chromatographic profile of the samples commercialized as "erva-de-bicho" was similar to the Polygonum acuminatum or Polygonum ferrugineum profiles, or did not present peaks in the chromatograms. The chromatographic profiles were monitored in the 254 nm and 362 nm.

Antibacterial activity of orsellinates

Para obter novos compostos com atividade antibacteriana, foram preparados os derivados 2,4-diidróxi-6-metilbenzoatos (orselinatos) e o ácido 2,4-diidróxi-6-metilbenzóico (ácido orselínico) através de reacões de alcoólise do ácido lecanórico. Todas as substâncias foram testadas contra bactérias Gram-positivas e Gram-negativas pelo método da microdiluicão. Staphylococcus aureus, Xanthomonas campestris var. vesicatoria and Ralstonia solanacearum foram mais sensíveis ao 2,4-diidróxi-6-metilbenzoato de n-propila, 2,4-diidróxi-6-metilbenzoato de n-pentila e 2,4-diidróxi-6-metilbenzoato de n-hexila com valores de CIM (Concentracão Inibitória Mínima) variando de 62,5 a 7,8 µg.mL1. Esses resultados mostraram que a homologacão da cadeia carbônica pode conduzir a compostos mais ativos.