Search

In this article, the first complete phytochemical study of Stachys sylvatica (Lamiaceae) aerial parts, collected in Tuscan-Emilian Apennine, is reported. Twenty-three known compounds were isolated from the chloroform, chloroform-methanol 9:1 and methanol extracts; they were subsequently characterized by means of one- and two-dimensional nuclear magnetic resonance spectroscopy (1D- and 2D-NMR) and mass spectrometry as six simple phenolic derivatives (chlorogenic acid (1), caffeic acid (2), p-coumaric acid methyl ester (3), niduloic acid (4), hydroxytyrosol (5), tyrosol (6)), one glycosylated aliphatic alcohol (ebracteatoside B (7)), six glycosylated phenylpropanoids (decaffeoyl verbascoside (8), lavandulifolioside (9), betanyoside F (10), verbascoside (11), isoacteoside (12), cystanoside D (13)), four flavonoids (stachyspinoside (14), chrysoeriol 7-O-β-D-glucopyranoside (15), naringenin 7-O-(6"-E + Z-p-coumaroyl)-β-D-glucopyranoside (16), apigenin 7-O-(6"-E + Z-p-coumaroyl)-β-D-glucopyranoside (17)), three lignans (syringaresinol 4'-O-β-D-glucopyranoside (18), pinoresinol 4-O-β-D-glucopyranoside (19), 2-episesaminol 2-O-β-D-glucopyranoside (20)) and three ionones (loliolide (21), vomifoliol (22), (3S,5R,6R,7E,9R)-3,5,6,9-tetrahydroxy-7-megastigmene (23)). In addition, a further phenolic derivative (ethyl caffeate (b)) and four carboxylic acids (azelaic acid (a), trihydroxyoctadecadienoic acid (c), trihydroxyoctadecenoic acid (d) and dihydroxydodecadienoic acid (e)) have been tentatively identified by ultra-high performance liquid chromatography coupled to an electrospray ionization source high-resolution Orbitrap mass spectrometer (UHPLC-ESI-HR-Orbitrap/MS). Chemosystematic relationships between S. sylvatica and other related species were highlighted. [ABSTRACT FROM AUTHOR]

Leaf-cutting ants are insects of great economic importance which cause economic losses in numerous crops. Compounds that modulate behaviour, and among these natural repellents, show promise in integrated pest management strategies. Tea tree oil has been found to be repellent to certain insect pests, so this study aimed at identifying the effect of tea tree on foraging behaviour in Acromyrmex spp. ants in laboratory as well as in field trials. In laboratory bioassays, a repellent dose response effect of tea tree oil was observed, where concentrations of 0.0001 to 0.1% tea tree did not affect ant behaviour, but concentrations of 1 and 10% repelled ants. In the laboratory, the repellent effect of tea tree was lost after four days and its effect on ant behaviour was evident only at very short distances (less than 1 cm). In the field, ants avoided walking through filter papers treated with tea tree at 1% placed on the foraging trails, and food resources surrounded by tea tree at 1% were not collected. Tea tree is a potent short term leaf-cutting ant repellent and attractive food sources could be protected from leaf-cutting ants attack by this oil. [ABSTRACT FROM AUTHOR]

Phytochemical reinvestigation on the whole plants of Derris laxiflora Benth. afforded two new diprenylated flavanones, derriflavanones B and C (1–2), together with thirty-two known compounds, including sixteen flavonoids (3–18), eleven aromatic compounds (19–29), and five chlorophylls (30–34). All known compounds were first isolated from this plant. The structures of these compounds were determined by analysis of the NMR spectroscopy, mass data, IR spectra, UV spectra, optical rotation and by comparison with literature data. [ABSTRACT FROM AUTHOR]

Fireflies (Coleoptera: Lampyridae) are charismatic insects that have been fruitful model systems in biotechnology. However, lack of information about firefly taxonomy and ecology renders species identification a hard task, especially in the Neotropical region, where fireflies are most diverse. A major gap in the literature on Neotropical fireflies is the lack of knowledge on species' ecological niches and habitats, which are fundamental aspects for understanding their biology. Here, we provide an annotated checklist of the firefly fauna of the Serra dos Órgãos mountain range (Rio de Janeiro State, Southeastern Brazil), with information on the natural history of each species. We assembled data in three ways: monthly sampling with Malaise traps and active search along an elevational transect from 130 to 2,170 m, over 2 years (2014–2016), extensive field observations, and extracted from historical species records for the Serra dos Órgãos from museum specimens in key collections in Brazil and Europe. We provide a taxonomic key to the genera recorded in the region, and a differential diagnosis for each species, highlighting key references for each taxon. We report 58 species representing 21 genera, making the Serra dos Órgãos one of the richest firefly hotspots on Earth. Most species are restricted to one or two habitat types and/or just one of the regional seasons (warm or cool), and many were only collected either by malaise traps or active search, underlining the importance of sampling different habitat types and seasons, and using different sampling methods when surveying fireflies. Out of the 51 species observed in the field, 49 were active either during the day or the night, although two species – Photuris elliptica and Pyrogaster nigrolineatus – were active in both periods, which is rare in fireflies. [ABSTRACT FROM AUTHOR]

Dysregulation of isoprenoid biosynthesis is implicated in numerous biochemical disorders that play a role in the onset and/or progression of age-related diseases, such as hypercholesterolemia, osteoporosis, various cancers, and neurodegeneration. The mevalonate metabolic pathway is responsible for the biosynthesis of the two key isoprenoid metabolites, farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP). Post-translational prenylation of various proteins, including the small GTP-binding proteins (GTPases), with either FPP or GGPP is vital for proper localization and activation of these proteins. Prenylated GTPases play a critical role in cell signaling, proliferation, cellular plasticity, oncogenesis, and cancer metastasis. Pre-clinical and clinical studies strongly suggest that inhibition of protein prenylation can be an effective treatment for non-skeletal cancers. In this review, we summarize the most recent drug discovery efforts focusing on blocking protein farnesylation and/or geranylgeranylation and the biochemical and structural data available in guiding the current on-going studies in drug discovery. Furthermore, we provide a summary on the biochemical association between disruption of protein prenylation, endoplasmic reticulum (ER) stress, unfolded protein response (UPR) signaling, and cancer. [ABSTRACT FROM AUTHOR]

Paspalum commersonii(Poaceae) is a herbaceous perennial weed distributed in the tropics and subtropics regions and grows mainly in the moist, or even flooded soil. It often appears in the rice field as a competitive weed and difficult to manage. Its strong competitive nature indicates possible allelopathic potential ofP. commersonii. However, no studies have been found yet on the allelopathic activity ofP. commersonii. Thus, we investigated the allelopathic potential of this weed and determined its allelopathic substances. Aqueous methanol extracts ofP. commersoniishowed concentration-dependent inhibitory activity on the seedling growth of cress, alfalfa, rapeseed, lettuce, barnyard grass, foxtail fescue, Italian ryegrass, and timothy. Two substances were isolated through bioassay-guided fractionation and their structures were determined through spectral data as dehydrovomifoliol and loliolide. Dehydrovomifoliol and loliolide started inhibiting the shoot and root growth of cress at concentrations greater than 3 and 0.03 mM, respectively. The concentrations required for 50% inhibition (I50) of cress shoot and root growth were 3.34 and >3.50 mM for dehydrovomifoliol and 0.04 and 0.05 mM for loliolide, respectively. These results indicate that both substances may affect the inhibitory activity ofP. commersonii. [ABSTRACT FROM AUTHOR]

Geranylgeranyl diphosphate is a 20-carbon isoprenoid phospholipid whose lipid moiety can be post-translationally incorporated into proteins to promote membrane association. The process of geranylgeranylation has been implicated in anti-proliferative effects of clinical agents that inhibit enzymes of the mevalonate pathway (i.e. statins and nitrogenous bisphosphonates) as well as experimental agents that deplete geranylgeranyl diphosphate. Inhibitors of geranylgeranyl diphosphate synthase are an attractive way to block geranylgeranylation because they possess a calcium-chelating substructure to allow localization to bone and take advantage of a unique position of the enzyme within the biosynthetic pathway. Here, we describe recent advances in geranylgeranyl diphosphate synthase expression and inhibitor development with a particular focus on the molecular mechanisms that link geranylgeranyl diphosphate to cell proliferation via geranylgeranylated small GTPases. [ABSTRACT FROM AUTHOR]

Context:Various studies have shown that the leaf extracts ofSpondias mombinLinn (Anacardiaceae) possess pharmacological properties such as antioxidant and antiviral effects. However, no biological activity from its essential oil has been reported in literature. Objective:To analyse the chemical constituents, cytotoxic activity and antioxidant capability of the essential oils from fresh and dried leaves ofS. mombin. Materials and methods:Hydrodistillation using Clevenger-type apparatus was employed to obtain the essential oil. Oil analysis was performed using an HP 6890 Gas Chromatograph coupled with an HP 5973 Mass Selective Detector. The cytotoxicity bioassay was carried out using the brine shrimp lethality test (10,000–0.01 μg/mL). Additionally, the reactive oxygen species scavenging potential of the twoS. mombinoils (1000–200 μg/mL) were investigated using a hydroxyl radical scavenging and ferric iron reducing system. Results:Chemical analysis of essential oils fromS. mombinrevealed the presence of 41 compounds, with predominance of monoterpenoids, sesquiterpenoids and non-terpenoids derivatives. In both fractions, the principal component was β-caryophellene (27.9–30.9%), followed by γ-cadinene (9.7–12.3%). There was an increase in the oxygenated monoterpenoid contents and a concomitant decrease in the amounts of sesquiterpenoids hydrocarbons observed on drying the leaves. The oil obtained from the fresh leaves was more active than that obtained from dried leaves, with LC50values (from the brine shrimp lethality assay) of 0.01 and 4.78 μg/mL, respectively. The two oils (from fresh and dried leaves) at 1.0 mg/mL scavenged hydroxyl radical by 83% and 99.8%, respectively. Moreover, they reduced ferric ion significantly and compared favourably with vitamin C. Conclusions:Essential oil derived from the leaves ofS. mombincould hold promise for future application in the treatment of cancer-related diseases. [ABSTRACT FROM AUTHOR]

Geranylgeranyl diphosphate is a 20-carbon isoprenoid phospholipid whose lipid moiety can be post-translationally incorporated into proteins to promote membrane association. The process of geranylgeranylation has been implicated in anti-proliferative effects of clinical agents that inhibit enzymes of the mevalonate pathway (i.e. statins and nitrogenous bisphosphonates) as well as experimental agents that deplete geranylgeranyl diphosphate. Inhibitors of geranylgeranyl diphosphate synthase are an attractive way to block geranylgeranylation because they possess a calcium-chelating substructure to allow localization to bone and take advantage of a unique position of the enzyme within the biosynthetic pathway. Here, we describe recent advances in geranylgeranyl diphosphate synthase expression and inhibitor development with a particular focus on the molecular mechanisms that link geranylgeranyl diphosphate to cell proliferation via geranylgeranylated small GTPases. [ABSTRACT FROM AUTHOR]

Background: Molecular methods, in particular PCR, are increasingly used for the diagnosis of enteric pathogens in stool samples. In high-endemicity settings, however, asymptomatic carriage or residual DNA from previous infections will hamper the interpretation of positive test results. We assessed the quantitative dimension of this problem in schoolchildren in the rural highlands of Madagascar. Methods: Stool samples were collected from 410 apparently healthy Madagascan schoolchildren and analysed by multiplex real-time PCR for enteroinvasive bacteria (Salmonella spp., Shigella spp./enteroinvasive Escherichia coli (EIEC), Campylobacter jejuni, Yersinia spp.), enteric protozoa (Entamoebea histolytica, Giardia duodenalis, Cryptosporidium spp., Cyclospora spp.), and helminths (Ascaris lumbricoides, Ancylostoma spp., Necator americanus, Strongyloides stercoralis). Symptoms of gastrointestinal disease were assessed. Results: Among the 410 samples, we detected Giardia duodenalis in 195, Campylobacter jejuni in 91, Ascaris lumbricoides in 72, Cyclospora cayetanenesis in 68, Shigella spp./EIEC in 56, and Strongyloides stercoralis and Cryptosporum spp. in 1 case each. Salmonella spp., Yersinia spp. and hookworms were not observed. Relative risk assessment suggested few and incoherent associations with pathogen detections, indicating asymptomatic carriage or DNA residuals. Only 26.1% of the schoolchildren were tested negative for all analysed pathogens. Conclusions: The very high risk of detecting traces of asymptomatic carriage or residual DNA from previous infections limits the value of highly sensitive PCR for the causal attribution of detected enteric pathogens from stool samples to an infectious gastrointestinal disease in the high-endemicity setting. Evaluated standards for the interpretation of such results are needed both for the diagnostic routine and for epidemiological assessments. [ABSTRACT FROM AUTHOR]

Four phosphonate derivates of 2,3-diphosphoglycerate (2,3-DPG), in which the phosphate group is replaced by a methylene or difluoromethylene, were successfully synthesized for use as allosteric modulators of hemoglobin (Hb) O2 affinity. The syntheses were accomplished in four steps and the reagents were converted to their potassium salts to allow for effective binding with Hb in aqueous media. O2 equilibrium measurements of the chemically modified Hbs exhibited P50 values in the range 8.9-12.8 with Hill coefficients in the range of 1.5-2.4. [ABSTRACT FROM AUTHOR]

From the ethyl acetate fraction of the fruiting body of Ganoderma lucidum, a new triterpenoid, ethyl 7β-hydroxy-4,4,14α-trimethyl-3,11,15-trioxo-5α-chol-8-en-24-oate (4), named ethyl lucidenates A, along with three known compounds, ganodermanondiol (1), lucidumol B (2) and methyl lucidenates A (3) were isolated by silica gel column, ODS column chromatography and PHPLC. Their structures were established on the basis of spectroscopic analysis and chemical evidence. The isolated compounds were tested using in vitro MTT assay for their cytotoxic activities against the K562, HL-60, CA46, HepG2, SW480 and SMMC-7221 cancer cell lines. Among them, compound 4 showed cytotoxicity against HL-60 and CA46 cancer cell lines with IC50 values of 25.98 and 20.42 µg mL−1, respectively. [ABSTRACT FROM AUTHOR]

Leaf-cutting ants, being the principal herbivores and ecosystem engineers in the Neotropics, have been considered to be a keystone species in natural ecosystems and agroecosystems, due to the direct and indirect effects of their plant defoliation activities. This review summarizes current concepts of the biological and ecological importance of leaf-cutting ants. The ants' pest status is briefly assessed from both ecological and evolutionary points of view. A general overview of control measures is provided. Leaf-cutting ants have evolved physical, symbiotic and behavioural mechanisms that allow them to overcome the chemical, biological, mechanical and cultural methods that have been used to manage their populations. Given the highly complex ecology of these ants, simple methods of control should not be expected. Sound management strategies must alternate between, and combine, different methods. [ABSTRACT FROM PUBLISHER]

Context: Piper aduncum L. (Piperaceae) produces an essential oil (dillapiole) with great exploitative potential and it has proven effects against traditional cultures of phytopathogens, such as fungi, bacteria and mollusks, as well as analgesic action with low levels of toxicity. Objective: This study investigated the in vivo anti-inflammatory activity of dillapiole. Furthermore, in order to elucidate its structure-anti-inflammatory activity relationship (SAR), semisynthetic analogues were proposed by using the molecular simplification strategy. Materials and methods: Dillapiole and safrole were isolated and purified using column chromatography. The semisynthetic analogues were obtained by using simple organic reactions, such as catalytic reduction and isomerization. All the analogues were purified by column chromatography and characterized by 1H and 13C NMR. The anti-inflammatory activities of dillapiole and its analogues were studied in carrageenan-induced rat paw edema model. Results: Dillapiole and di-hydrodillapiole significantly ( p<0.05) inhibited rat paw edema. All the other substances tested, including safrole, were less powerful inhibitors with activities inferior to that of indomethacin. Discussion and conclusion: These findings showed that dillapiole and di-hydrodillapiole have moderate anti-phlogistic properties, indicating that they can be used as prototypes for newer anti-inflammatory compounds. Structure-activity relationship studies revealed that the benzodioxole ring is important for biological activity as well as the alkyl groups in the side chain and the methoxy groups in the aromatic ring. [ABSTRACT FROM AUTHOR]

The methanolic crude extract from the roots of Jacquinia flammea showed moderate antifungal activity against dermatophytes and very strong antifungal activity against Colletotrichum gloeosporioides. The bioassay-guided purification of the extract, using a combination of vacuum-liquid chromatography and high performance liquid chromatography, allowed the identification of sakurasosaponin (1) as the main metabolite responsible for the antifungal activity. [ABSTRACT FROM AUTHOR]

New lipophilic alendronate amidated derivatives 1a--1d anchored alkyl chains (C nH2 n++1, n == 12, 14, 16, 18) had been obtained through the reaction of alendronate with carboxylic acid under anhydrous condition. The physicochemical parameters, such as the solubility and partition coefficient Po/w in n-octanol/water, were determined through calculation by performing reversion phase high-performance liquid chromatography (RP-HPLC). The results showed that the derivatives had improved lipophilicity compared with alendronate. The in vivo bioactivities of the derivatives were investigated using the hindlimb unloading growing rats'' model. The results showed that the derivatives had in vivo bioactivity against hindlimb unloading growing rats'' bone loss, which indicated that the lipophilic derivative would be a promising new potent bisphosphates for treatment of the osteoporosis. [ABSTRACT FROM AUTHOR]

A phytochemical investigation of the leaves and stems of Peperomia obtusifolia (Piperaceae) yielded a new flavone C-diglycoside isoswertisin-4'-methyl-ether-2''α-L-rhamnoside (1), along with four known compounds: isoswertisin-2''α-L-rhamnoside (2), (+)-diayangambin (3), 2-episesalatin (4) and corchoionoside C (5). The structures of the two flavone C-diglycosides (1, 2) were elucidated on the basis of 1D and 2D NMR spectroscopy and MS spectrometric data. These flavones were evaluated by bioautographic assay against Cladosporium cladosporioides and C. sphaerospermum and showed weak antifungal activity. [ABSTRACT FROM AUTHOR]

The Iowa Center for Research on Botanical Dietary Supplements seeks to optimize Echinacea, Hypericum, and Prunella botanical supplements for human-health benefit, emphasizing anti-viral, anti-inflammatory, and anti-pain activities. This mini-review reports on ongoing studies on Hypericum. The Center uses the genetically diverse, well-documented Hypericum populations collected and maintained at the USDA-ARS North Central Regional Plant Introduction Station (NCRPIS), and the strength of research in synthetic chemistry at Iowa State University to tap natural diversity, to help discover key constituents and interactions among constituents that impact bioactivity and toxicity. The NCRPIS has acquired more than 180 distinct populations of Hypericum, with a focus on Hypericum perforatum L. (Hypericaceae), representing about 13% of currently recognized taxa. Center chemists have developed novel synthetic pathways for key flavones, acyl phloroglucinols, hyperolactones, and a tetralin that have been found in Hypericum, and these compounds are used as standards and for bioactivity studies. Both light-dependent and light-independent anti-viral activities have been identified by using bioactivity-guided fractionation of H. perforatum and a HIV-1 infection test system. Our Center has focused on light-independent activity, potentially due to novel chemicals, and polar fractions are undergoing further fractionation. Anti-inflammatory activity has been found to be light-independent, and fractionation of a flavonoid-rich extract revealed four compounds (amentoflavone, chlorogenic acid, pseudohypericin, and quercetin) that interacted in the light to inhibit lipopolysaccharide-induced prostaglandin E2 activity. The Center continues to explore novel populations of H. perforatum and related species to identify constituents and interactions of constituents that contribute to potential health benefits related to infection. [ABSTRACT FROM AUTHOR]

With the aim of creating new bisubstrate inhibitors of protein farnesyltransferase (FTase), new carboxylic farnesyl pyrophosphate analogues have been designed and synthesized. The original structures are built around three elements: a prenyl moiety, a 1,4-diacid motif and an imidazole ring. All the compounds were evaluated for their ability to inhibit FTase and compared with the corresponding derivatives lacking the imidazole ring, synthesized for that purpose. These new compounds are not bisubstrate inhibitors probably because the imidazole ring is not in the right position to interact with the zinc atom. However these derivatives display FPP competitive inhibition with a good activity in the carboxylic farnesyl pyrophosphate analogues series. [ABSTRACT FROM AUTHOR]

Loliolide content was determined in 13 marine algae including red, brown and green algae collected from the Black Sea, the Dardanelles and the Aegean Sea. Identification and quantification were performed by gas chromatography-mass spectrometry. The loliolide content in green alga is 1.76 µg g-1, ranges from 0.14 to 4.35 µg g-1 in red and from 0.18 to 4.83 µg g-1 in brown algae. The results obtained are in the same range as previously reported for algae, as well as terrestrial plants. This article represents the first report of loliolide occurrence in green algae. [ABSTRACT FROM AUTHOR]

From an Argentine collection of the tropical tree Rollinia emarginata (Annonaceae), vomifoliol, dehydrovomifoliol, blumenol C, loliolide, 7-epiloliolide, vanillin, dihydroactinolide, as well as other common plant constituents were obtained, and identified by their NMR and MS features compared with authentic samples. Antifeedant and toxic actions were exerted to the polyphagous moth Spodoptera frugiperda by the ethanol extract of the plant, at 250 ppm in the larval diet. Additionally, in greenhouse studies, a 200 ppm aqueous solution of the extract produced a post-emergency herbicidal effect on the annual weed common lambsquarter (Chenopodium album). [ABSTRACT FROM AUTHOR]

A novel compound of a rare class of secondary metabolites, 3-geranyl-4-hydroxybenzoic acid derivative, methyl xerophytolate A (2), was isolated from the crude extract of Xerophyta plicata (Velloziaceae) collected in Rio de Janeiro, Brazil. The structure of 2 was elucidated using spectroscopic methods. [ABSTRACT FROM AUTHOR]

Four phenolic glycosides (1-4), including two new ones (3 and 4), have been isolated from the stems of Casearia multinervosa and identified as arbutin (1), 4- O - E -caffeoylarbutin (2), 4- O - E -coumaroylarbutin (3) and 4- O - E -feruloylarbutin (4), respectively. In addition, the two known phenolic glycosides (1 and 2) were also isolated from the leaves. Structures were elucidated on the basis of spectroscopic evidence. Compounds 1-4 were tested for cytotoxicity against the P388 mouse lympholytic cell line by an ATP Lite-M assay method and showed mild to moderate activity. [ABSTRACT FROM AUTHOR]

In this research, extracts prepared from plant materials were tested against Mycobacterium tuberculosis H37Rv (ATCC 27294). Of the 107 plants tested, five exhibited more than 90% inhibition of growth of Mycobacterium tuberculosis, at concentrations lower than 100 μg=ml. Jervin from Veratrum album L., usnic acid from Usnea barbata (L.) MoH, and alantolactone from Inula helenium L. subsp. turcoracem-osa were isolated and their minimum inhibitory concentrations (MICs) were determined as 25, 12.5, and 3.125 μg=ml, respectively. [ABSTRACT FROM AUTHOR]

Two new bromophenols, ( E )-3-(2,3-dibromo-4,5-dihydroxyphenyl)-2-methylpropenal ( 1 ) and 3-(2,3-dibromo-4,5-dihydroxyphenyl)-2-methyl-1-propanol ( 2 ), together with 11 known bromophenols ( 3 - 13 ), were isolated from the ethanolic extract of the brown alga Leathesia nana S. et G. Their structures have been elucidated by spectroscopic methods, including IR, MS, HRMS, 1D and 2D NMR techniques. [ABSTRACT FROM AUTHOR]