Publications by authors named "Lydia Fumiko Yamaguchi"

Chromatographic fractionation of CHCl:MeOH (1:1) extract of Schott cultivated in Egypt afforded four compounds, lupeol acetate (), -13--manoyl oxide (), 5-methoxymethyl-7,8-dimethyltocol (), and -tocopherol quinone (). The planar structures of the isolated compounds were concluded based on HRESIMS and NMR spectroscopy. X-ray crystallography of is reported herein for the first time and its unambiguous absolute configuration was deduced from anomalous dispersion.

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is a species of tick in the family Ixodidae, with equids and capybaras among its preferred hosts. In this study, the acaricidal activity of the essential oil (EO) from and its main component, Dillapiole, were evaluated against larvae of to establish lethal concentration values and assess the effects of these compounds on tick enzymes. Dillapiole exhibited slightly greater activity (LC = 3.

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A proposed treatment for malaria is a combination of fosmidomycin and clindamycin. Both compounds inhibit the methylerythritol 4-phosphate (MEP) pathway, the parasitic source of farnesyl and geranylgeranyl pyrophosphate (FPP and GGPP, respectively). Both FPP and GGPP are crucial for the biosynthesis of several essential metabolites such as ubiquinone and dolichol, as well as for protein prenylation.

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Toxoplasmosis is a tropical and neglected disease caused by the parasitic protozoa . Conventional treatment with sulfadiazine and pyrimethamine plus folinic acid, has some drawbacks, such as inefficacy in the chronic phase, toxic side effects, and potential cases of resistance have been observed. In this study, the activity of essential oils (EOs) from three species and their main constituents, including α-Pinene ( and ), β-Pinene (), and dillapiole (), were evaluated against tachyzoites of .

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is the etiological agent of human malaria, one of the most widespread diseases in tropical and subtropical regions. Drug resistance is one of the biggest problems in controlling the disease, which leads to the need to discover new antimalarial compounds. One of the most promissory drugs purposed is fosmidomycin, an inhibitor of the biosynthesis of isoprene units by the methylerythritol 4-phosphate (MEP) pathway, which in some cases failed in clinical studies.

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Species richness in tropical forests is correlated with other dimensions of diversity, including the diversity of plant-herbivore interactions and the phytochemical diversity that influences those interactions. Understanding the complexity of plant chemistry and the importance of phytochemical diversity for plant-insect interactions and overall forest richness has been enhanced significantly by the application of metabolomics to natural systems. The present work used proton nuclear magnetic resonance spectroscopy ( H-NMR) profiling of crude leaf extracts to study phytochemical similarity and diversity among Piper plants growing naturally in the Atlantic Rainforest of Brazil.

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The chemical composition of seedlings and adult plants of several species were analyzed by H NMR spectroscopy combined with principal component analysis (PCA) and HPLC-DAD, HPLC-HRESIMS and GC-MS data. The chromatographic profile of crude extracts from leaves of species showed remarkable differences between seedlings and adult plants. Adult leaves of accumulate dihydrobenzofuran neolignans, contain tetrahydrofuran lignans, and prenylated benzoic acids are found in adult leaves of and .

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The genus Hbner (Geometridae: Larentiinae) comprises 254 valid species, 217 of which were described from the Neotropics and 31 of those having their type locality in Brazil. Since this species rich genus has never been revised, and may potentially include many cryptic undescribed species, embodies a problematic taxonomic scenario. The actual diversity of is greatly underestimated and the Brazilian fauna is poorly known, both because of inadequate sampling and because of the potential existence of cryptic species "hidden" within some nominal taxa.

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Altered cell metabolism is a hallmark of cancer and critical for its development. Particularly, activation of one-carbon metabolism in tumor cells can sustain oncogenesis while contributing to epigenetic changes and metabolic adaptation during tumor progression. We assessed whether increased one-carbon metabolism activity is a metabolic feature of invasive ductal carcinoma (IDC).

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A longstanding paradigm in ecology is that there are positive associations between herbivore diversity, specialization, and plant species diversity, with a focus on taxonomic diversity. However, phytochemical diversity is also an informative metric, as insect herbivores interact with host plants not as taxonomic entities, but as sources of nutrients, primary metabolites, and mixtures of attractant and repellant chemicals. The present research examines herbivore responses to phytochemical diversity measured as volatile similarity in the tropical genus Piper.

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Common bean (Phaseolus vulgaris) is present in the daily diet of various countries and, as for other legumes, has been investigated for its nutraceutical potential. Thus, 16 genotypes from different gene pools, representing seven types of seed coats and different responses to pathogens and pests, were selected to verify their isoflavone contents. The isoflavonoids daidzein and genistein and the flavonols kaempferol, myricetin, and quercetin were found.

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The presence of peptides has been identified in all African pipid genera; nevertheless, little is known about skin secretion of South American frog genus Pipa. Skin secretion from captive and wild Pipa carvalhoi were obtained in the presence or absence of norepinephrine stimulation. The <10 kDa fraction was analyzed by liquid chromatography and mass spectrometry, searching for peptides.

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Schistosomiasis is a neglected disease with public health importance in tropical and subtropical regions. An alternative to the disease control is the use of molluscicides to eliminate or reduce the intermediate host snail population causing a reduction of transmission in endemic regions. In this study nine extracts from eight Piperaceae species were evaluated against Biomphalaria glabrata embryos at blastula stage.

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Background: Schistosomiasis is one of the most significant diseases in tropical countries and affects almost 200 million people worldwide. The application of molluscicides to eliminate the parasite's intermediate host, Biomphalaria glabrata, from infected water supplies is one strategy currently being used to control the disease. Previous studies have shown a potent molluscicidal activity of crude extracts from Piper species, with extracts from Piper tuberculatum being among the most active.

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