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1.
PLOS Glob Public Health ; 3(2): e0001120, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36962978

RESUMO

Antimicrobial resistance (AMR) is a global public health threat. Surveillance of AMR requires affordable, rapid, and user-friendly diagnostic methods. Our aim was to develop a low-cost thermocycler to perform polymerase chain reaction (PCR). We developed a smartphone-operated PCR thermal cycler using locally available recycled materials. The thermal cycler was used for the amplification for three bacterial genes-bla-TEM, bla-CTXM and 16s rRNA in human urine samples. The performance of custom-built thermal cycler was compared with commercial thermal cycler. The thermal cycler was portable (<1kg weight), required 12 V power supply, 25 µL of solution, and cost only USD50.0. Temperature and time conditions were instructed using a custom-built smartphone application. The ramping rate of was 0.23°C for heating and 0.43°C for cooling. The reported temperatures were within ± 0.5°C of set temperature. The human urine samples were highly resistance and multi-resistant. Nearly 46% (n = 54) E. coli isolates were positive in ESBL screening test. The custom-built thermocycler was able to accurately predict the presence of bla-TEM, bla-CTXM genes, and 16s rRNA (n = 6). We developed and demonstrated a portable, low-cost, easy-to-use, and smartphone-operated PCR thermal cycler. Since it is portable, it can be used in remote location and field settings, including places without stable power supply. The use of the thermal cycler system can be extended, beyond the detection of AMR genes, e.g., in clinical diagnosis, genetics, forensic analysis, and environmental protection.

2.
J Nepal Health Res Counc ; 20(2): 454-459, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36550728

RESUMO

BACKGROUND: Sickle cell anemia is an inherited blood disorder caused due to a point mutation at the sixth codon of the ?-globin gene of both alleles. Sickle cell traits occur when the mutation is in one of the two alleles of the ?-globin genes. This study was carried out in the Tharu community, which is an indigenous and minority group mostly residing in the Terai region of Nepal. They are also considered as the most vulnerable group for inheriting Sickle cell anemia. METHODS: Purposive sampling, which included 130 Tharu individuals of Kanchanpur district of Nepal, was considered for the study. The survey was conducted using a descriptive questionnaire that contained relevant information including the family history of Sickle cell anemia. This was followed by the analysis of blood samples to determine the prevalence of Sickle cell anemia and Sickle cell traits. Primer-mediated enzymatic amplification of target sequences in genomic DNA followed by restriction endonuclease assay with an enzyme DdeI was carried out for the confirmation. RESULTS: Among 130 individuals, only 55.4% had basic knowledge about Sickle cell anemia. After screening for sickle cell anemia from 60 participants, 27 (45%) of them were found to be in the heterozygous state (carrier, Hb AS) and 28 (46.7%) were in the homozygous (normal, AA Hb) state with 5 (8.3%) having the diseased hemoglobin (Hb SS) variant of Sickle cell anemia. CONCLUSIONS: This study demonstrated a high prevalence of Sickle cell anemia and Sickle cell traits in the Tharu community. This study may be beneficial for concerned personnel policymakers to reduce sickle cell cases by improving genetic literacy among the Tharu community.


Assuntos
Anemia Falciforme , Traço Falciforme , Humanos , Hemoglobina Falciforme/genética , Nepal/epidemiologia , Anemia Falciforme/epidemiologia , Anemia Falciforme/genética , Hemoglobinas
3.
Molecules ; 27(24)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36558090

RESUMO

Despite ongoing vaccination programs against COVID-19 around the world, cases of infection are still rising with new variants. This infers that an effective antiviral drug against COVID-19 is crucial along with vaccinations to decrease cases. A potential target of such antivirals could be the membrane components of the causative pathogen, SARS-CoV-2, for instance spike (S) protein. In our research, we have deployed in vitro screening of crude extracts of seven ethnomedicinal plants against the spike receptor-binding domain (S1-RBD) of SARS-CoV-2 using an enzyme-linked immunosorbent assay (ELISA). Following encouraging in vitro results for Tinospora cordifolia, in silico studies were conducted for the 14 reported antiviral secondary metabolites isolated from T. cordifolia-a species widely cultivated and used as an antiviral drug in the Himalayan country of Nepal-using Genetic Optimization for Ligand Docking (GOLD), Molecular Operating Environment (MOE), and BIOVIA Discovery Studio. The molecular docking and binding energy study revealed that cordifolioside-A had a higher binding affinity and was the most effective in binding to the competitive site of the spike protein. Molecular dynamics (MD) simulation studies using GROMACS 5.4.1 further assayed the interaction between the potent compound and binding sites of the spike protein. It revealed that cordifolioside-A demonstrated better binding affinity and stability, and resulted in a conformational change in S1-RBD, hence hindering the activities of the protein. In addition, ADMET analysis of the secondary metabolites from T. cordifolia revealed promising pharmacokinetic properties. Our study thus recommends that certain secondary metabolites of T. cordifolia are possible medicinal candidates against SARS-CoV-2.


Assuntos
COVID-19 , Plantas Medicinais , Humanos , Glicoproteína da Espícula de Coronavírus/metabolismo , SARS-CoV-2/metabolismo , Simulação de Acoplamento Molecular , Plantas Medicinais/metabolismo , Altitude , Nepal , Antivirais/química , Ligação Proteica , Simulação de Dinâmica Molecular
4.
Int J Microbiol ; 2021: 9948738, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34249126

RESUMO

Flavonoids have achieved widespread importance in pharmaceutical, food, and cosmetics industries. Furthermore, modification of these naturally occurring flavonoids to structurally diverse compounds through whole cell biotransformation with enhanced biological activities has numerous biotechnological applications. The present study investigated the biotransformation potential of Streptomyces species isolated from a high-altitude-soil sample towards selected flavonoid molecules. The biotransformed metabolites were confirmed by comparing the HPLC chromatogram with authentic compounds and LC-MS/MS analysis. Of these isolates, Streptomyces species G-18 (Accession number: MW663767.1) catalyzed isoflavone molecules daidzein and genistein to produce hydroxylated products at 24 h of reaction condition in a whole cell system. The hydroxylation of daidzein (4',7-dihydroxyisoflavone) was confirmed at 3'-position of the B ring to produce 3',4',7-trihydroxyisoflavone. In addition, Streptomyces species G-14 (Accession number: MW663770.1) and Streptomyces species S4L (Accession number: MW663769.1) also revealed the transformation of daidzein (4',7-dihydroxyisoflavone) to hydroxy daidzein at a distinct position than that of G-18 isolates, whereas thee Streptomyces species S4L reaction mixture with naringenin as a substrate also revealed the hydroxylated product. Our results demonstrated that microorganisms isolated from different ecological niches have broad application.

5.
BMC Complement Med Ther ; 21(1): 116, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33836728

RESUMO

BACKGROUND: A biofilm is an extracellular polymeric substance (EPS) composed of polysaccharides, proteins, nucleic acids, and lipids that impede antibiotics and immune cells, thus providing a shielded environment for bacterial growth. Due to biofilm formation, some microbes can show up to 1000 fold increased resistance towards the antibiotics than the normal planktonic forms. The study was conducted to screen the crude extracts of medicinal plants used in Nepal for their in vitro antibiofilm activities. METHODS: Total phenolic and total flavonoid contents were determined by using a Folin-Ciocalteau reagent and aluminium trichloride method, respectively. Resazurin assay was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The initial antibiofilm activities and their inhibitory concentration (IC50) values were determined by the microtiter based modified crystal violet staining method. RESULTS: Out of 25 different plant extracts were used for the study, methanolic extracts of 20 plants showed a biofilm inhibition activity against five different strong biofilm producing Escherichia coli strains. Calotropis gigantea exhibited inhibition against all five different E. coli strains with IC50 values ranging from 299.7 ± 20.5 to 427.4 ± 2.7 µg/mL. Apart from that, Eclipta prostrata also showed biofilm formation inhibition, followed by Eupatorium adenophorum, Moringa oleifera, Ocimum tenuifolium, Oxalis lantifolia, Prunus persica, and Urtica parviflora. The extracts of C. gigantea, E. prostrata, Mangifera indica, O. tenuifolium, P. persica, and U. parviflora exhibited a moderate to poor MIC value ranging from 625 to 2500 µg/mL. The highest amount of phenolic content (TPC) was found in Acacia catechu followed by Morus alba, which was 38.9 and 25.1 mg gallic acid equivalents, respectively. The highest amount of flavonoid content was found in A. catechu followed by M. indica, which was 27.1 and 20.8 mg quercetin equivalents, respectively. CONCLUSION: Extracts of C. gigantea, E. prostrata, P. persica, U. parviflora, and O. tenuifolium showed antibacterial as well as antibiofilm activity against pathogenic and strong biofilm producing E. coli. Thus, extracts or the pure compound from these medicinal plants could be used as antibiotics in the future.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Plantas Medicinais/química , Escherichia coli Uropatogênica/efeitos dos fármacos , Nepal
6.
Phytother Res ; 35(3): 1298-1312, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33037698

RESUMO

The whole world is entangled by the coronavirus disease (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), people are dying in thousands each day, and without an actual medication, it seems not possible for the bringing this global health crisis to a stop. Natural products have been in constant use since ancient times and are proven by time to be effective. Crude extract or pure compounds isolated from medicinal plants and/or herbs such as Artemisia annua, Agastache rugosa, Astragalus membranaceus, Cassia alata, Ecklonia cava, Gymnema sylvestre, Glycyrrhizae uralensis, Houttuynia cordata, Lindera aggregata, Lycoris radiata, Mollugo cerviana, Polygonum multiflorum, Pyrrosia lingua, Saposhnikoviae divaricate, Tinospora cordifolia etc. have shown promising inhibitory effect against coronavirus. Several molecules, including acacetin, amentoflavone, allicin, blancoxanthone, curcumin, daidzein, diosmin, epigallocatechin-gallate, emodin, hesperidin, herbacetin, hirsutenone, iguesterin, jubanine G, kaempferol, lycorine, pectolinarin, phloroeckol, silvestrol, tanshinone I, taxifolin, rhoifolin, xanthoangelol E, zingerol etc. isolated from plants could also be potential drug candidates against COVID-19. Moreover, these could also show promising inhibitory effects against influenza-parainfluenza viruses, respiratory syncytial virus, severe acute respiratory syndrome (SARS), and Middle East respiratory syndrome coronavirus (MERS-CoV). Here, we have reported 93 antiviral drug candidates which could be a potential area of research in drug discovery.


Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , Compostos Fitoquímicos/farmacologia , Plantas Medicinais/química , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Pandemias , SARS-CoV-2/efeitos dos fármacos
7.
Int J Microbiol ; 2020: 8817467, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32908528

RESUMO

Streptomyces are widely used for the production of secondary metabolites with diverse biological activities, including antibiotics. The necessity of alternative antimicrobial agents against multidrug-resistant pathogens is indispensable. However, the production of new therapeutics is delayed in recent days. Thus, the isolation of new Streptomyces species has drawn attention. Nepal-a country rich in biodiversity-has got high possibilities for the discovery of members of actinomycetes, especially in the higher altitudes. However, in vain, only a few screening research works have been reported from Nepal to date. Streptomyces species were isolated on ISP4 media, and characterization was performed according to morphological similarity and 16S rRNA sequence similarity using bioinformatic tools. Ethyl acetate extracts of Streptomyces species were prepared, and the antimicrobial activity was carried out using agar well diffusion technique. In this report, 18 Streptomyces species isolated from the soil were reported based on sequence analysis of 16S rRNA. Among them, 12 isolates have shown antibacterial activity against extended-spectrum beta-lactamase- (ESBL-) producing Escherichia coli. Here, we have also analyzed 16S rRNA in 27 Streptomyces species whose whole-genome sequence is available, which has revealed that some species have multiple copies of the 16S gene (∼1.5 kb) with significant variation in nucleotides. In contrast, some Streptomyces species shared identical DNA sequences in multiple copies of 16S rRNA. The sequencing of numerous copies of 16S rRNA is not necessary, and the molecular sequencing of this region is not sufficient for the identification of bacterial species. The Streptomyces species-derived ethyl acetate extracts from Nepalese soil demonstrate potential activity against ESBL-producing E. coli. Thus, they are potential candidates for antibiotics manufacturing in the future.

8.
Ann Clin Microbiol Antimicrob ; 18(1): 42, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31847837

RESUMO

BACKGROUND: Urinary tract infection (UTI) is one of the frequently diagnosed infectious diseases which is caused mainly by Escherichia coli. E. coli confers resistance against the two major classes of antibiotics due to the production of extended spectrum ß-lactamase enzymes (ESBL), biofilm, etc. Biofilm produced by uropathogenic E. coli (UPEC) protects from host immune system and prevent entry of antimicrobial compounds. The main objective of this cross-sectional study was to determine the correlation of biofilm production and antibiotic resistance as well as to characterize the pgaA and pgaC genes responsible for biofilm formation among uropathogenic ESBL producing E. coli. METHODS: A total of 1977 mid-stream urine samples were examined and cultured for bacterial strain identification. ESBL was detected by combined disc method following CLSI whereas biofilm formation was analyzed by semi-quantitative method. Furthermore, the pgaA and pgaC genes responsible for biofilm formation in UPEC were detected by multiplex PCR. All the statistical analyses were done via IBM SPSS Statistics 21 where Pearson's correlation test were used to determine correlation (-1 ≥ r ≤ 1). RESULTS: E. coli was the predominant causative agent, which accounted 159 (59.3%) of the Gram-negative bacteria, where 81 (50.9%) E. coli strains were found to be ESBL producers. In addition, 86 (54.1%) E. coli strains were found to be biofilm producers. Both the pgaA and pgaC genes were detected in 45 (93.7%) the UPEC isolates, which were both biofilm and ESBL producers. Moreover, there was a positive correlation between biofilm and ESBL production. CONCLUSION: The analyses presented weak positive correlation between biofilm and ESBL production in which biofilm producing UPEC harbors both pgaA and pgaC genes responsible for biofilm formation.


Assuntos
Biofilmes , Farmacorresistência Bacteriana , Infecções por Escherichia coli , Escherichia coli Uropatogênica , beta-Lactamases/genética , Adolescente , Adulto , Antibacterianos/farmacologia , Proteínas da Membrana Bacteriana Externa/genética , Biofilmes/efeitos dos fármacos , Criança , Pré-Escolar , Estudos Transversais , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/urina , Proteínas de Escherichia coli/genética , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Nepal , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/efeitos dos fármacos , Escherichia coli Uropatogênica/genética , Escherichia coli Uropatogênica/isolamento & purificação , Adulto Jovem
9.
BMC Res Notes ; 12(1): 734, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703724

RESUMO

OBJECTIVES: The study was carried out to optimize the phenotypic method to characterize the sickle cell trait (SCT), sickle cell anemia (SCA), and ß-thalassemia (ß-TT) suspected sample from tharu community of South Western province-5, Nepal. SCT and SCA were further evaluated by genotypic method employing amplification refractory mutation system (ARMS PCR). Moreover, Glucose 6 phosphate dehydrogenase (G6PD) was estimated in those hemoglobinopathy to observe its prevalence. The accurate and reliable method can play an important role in reduction of morbidity and mortality rate. RESULTS: The 100 suspected cases were subjected to phenotypic method adopting cellulose acetate electrophoresis and genotypic method using ARMS PCR which portraits (5%) SCA positive test showing HBS/HBS, (38%) SCT positive trait HBA/HBS and (36%) cases normal HBA/HBA. ß-TT (21%) cases were confirmed by electropherogram. G6PD deficiency was observed in (40%) of SCA, (18.4%) of SCT, (4.8%) of ß-TT and (2.8%) in normal cases. Increased G6PD were developed only in SCT (5.3%) and ß-TT (4.8%). The study highlighted sickle cell disorder (SCD) and ß-TT as the most common hemoglobinopathy coexisting with G6PD deficiency. Though hemoglobinopathy sometime could be protective in malaria but G6PD deficiency can cause massive hemolysis which may exacerbate the condition.


Assuntos
Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Hemoglobinopatias/epidemiologia , Eletroforese , Humanos , Concentração de Íons de Hidrogênio , Nepal/epidemiologia , Fatores de Risco
10.
Bioorg Chem ; 70: 210-221, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28087168

RESUMO

A series of benzoxazinones 1-28 were synthesized via reaction of anthranilic acid with various substituted benzoyl chlorides in the presence of triethylamine in chloroform. Compounds 1-18 showed a good inhibition of α-chymotrypsin with IC50±SEM values between 6.5 and 341.1µM. Preliminary structure-activity relationships studies indicated that the presence of substituents on benzene ring reduces the inhibitory potential of benzoxazinone. Also the increased inhibitory potential due to fluoro group at phenyl substituent was observed followed by chloro and bromo substituents. Compounds with strong electron donating or withdrawing groups on phenyl substituent, showed a good inhibitory potential at ortho>meta>para position. Kinetics studies showed diverse types of inhibition, except uncompetitive-type inhibition. The Ki values ranged between 4.7 and 341.2µM. Interestingly, most of these compounds were non-cytotoxic to 3T3 cell line at 30µM, except compounds 6, 14 and 15. Competitive inhibitors of chymotrypsin are like to inhibit other α-chymotrypsin-like serine proteases due to structural and functional similarities between them. The inhibitors identified during the current study deserve to be further studied for their therapeutic potential against abnormalities mediated by chymotrypsin or other serine protease.


Assuntos
Benzoxazinas/química , Benzoxazinas/farmacologia , Quimotripsina/antagonistas & inibidores , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Células 3T3 , Animais , Benzoxazinas/síntese química , Bovinos , Quimotripsina/metabolismo , Humanos , Cinética , Camundongos , Inibidores de Proteases/síntese química , Relação Estrutura-Atividade
11.
Bioorg Med Chem ; 24(16): 3387-95, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27374882

RESUMO

A library of benzimidazole derivatives 1-20 were synthesized, and studied for their α-chymotrypsin (α-CT) inhibitory activity in vitro. Kinetics and molecular docking studies were performed to identify the type of inhibition. Compound 1 was found to be a good inhibitor of α-chymotrypsin enzyme (IC50=14.8±0.1µM, Ki=16.4µM), when compared with standard chymostatin (IC50=5.7±0.13µM). Compounds 2-8, 15, 17, and 18 showed significant inhibitory activities. All the inhibitors were found to be competitive inhibitors, except compound 17, which was a mixed type inhibitor. The substituents (R) in para and ortho positions of phenyl ring B, apparently played a key role in the inhibitory potential of the series. Compounds 1-20 were also studied for their cytotoxicity profile by using 3T3 mouse fibroblast cells and compounds 3, 5, 6, 8, 12-14, 16, 17, 19, and 20 were found to be cytotoxic. Molecular docking was performed on the most active members of the series in comparison to the standard compound, chymostatin, to identify the most likely binding modes. The compounds reported here can serve as templates for further studies for new inhibitors of α-chymotrypsin and other chymotrypsin-like serine proteases enzymes.


Assuntos
Benzimidazóis/farmacologia , Quimotripsina/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Células 3T3 , Animais , Benzimidazóis/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Inibidores Enzimáticos/química , Técnicas In Vitro , Cinética , Camundongos , Simulação de Acoplamento Molecular , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
12.
Biomed Res Int ; 2015: 265425, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25738151

RESUMO

The worldwide increase of multidrug resistance in both community- and health-care associated bacterial infections has impaired the current antimicrobial therapy, warranting the search for other alternatives. We aimed to find the in vitro antibacterial activity of ethanolic extracts of 16 different traditionally used medicinal plants of Nepal against 13 clinical and 2 reference bacterial species using microbroth dilution method. The evaluated plants species were found to exert a range of in vitro growth inhibitory action against the tested bacterial species, and Cynodon dactylon was found to exhibit moderate inhibitory action against 13 bacterial species including methicillin-resistant Staphylococcus aureus, imipenem-resistant Pseudomonas aeruginosa, multidrug-resistant Salmonella typhi, and S. typhimurium. The minimum inhibitory concentration (MIC) values of tested ethanolic extracts were found from 31 to >25,000 µg/mL. Notably, ethanolic extracts of Cinnamomum camphora, Curculigo orchioides, and Curcuma longa exhibited the highest antibacterial activity against S. pyogenes with a MIC of 49, 49, and 195 µg/mL, respectively; whereas chloroform fraction of Cynodon dactylon exhibited best antibacterial activity against S. aureus with a MIC of 31 µg/mL. Among all, C. dactylon, C. camphora, C. orchioides, and C. longa plant extracts displayed a potential antibacterial activity of MIC < 100 µg/mL.


Assuntos
Antibacterianos/farmacologia , Bactérias/crescimento & desenvolvimento , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Antibacterianos/química , Humanos , Extratos Vegetais/química
13.
J Asian Nat Prod Res ; 16(2): 210-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24266421

RESUMO

The bioassay-guided fractionation of Daphne retusa Hemsl. has led to the isolation of a new aryl tetrahydronaphthalene lignan derivative named as daphnretusic acid (1), along with six new source compounds such as 5,7-dihydroxyflavone (2), 7-hydroxyflavone (3), 6-methoxyflavone (4), (+) pinoresinol (5), (+) sesamin (6), and ß-sitosterol-3-O-ß-D-glucopyranoside (7). Their structures were elucidated by (1)H NMR, (13)C NMR, 1D, 2D NMR, UV, IR, and EIMS analyses. All the fractions (n-hexane, CHCl3, AcOEt, CH3OH, and water) and pure compounds (1-7) were subjected to the assay of urease and α-chymotrypsin inhibitory activities. Chloroform and methanol soluble fractions showed moderate urease inhibition. Compound 2 exhibited significant urease inhibition with IC50 value 60.4 ± 0.72 µM, whereas compounds 1 and 3-7 remained inactive during urease inhibition and α-chymotrypsin bioassays.


Assuntos
Quimotripsina/antagonistas & inibidores , Daphne/química , Lignanas/isolamento & purificação , Tetra-Hidronaftalenos/isolamento & purificação , Tetra-Hidronaftalenos/farmacologia , Urease/antagonistas & inibidores , Flavonoides/química , Glucosídeos/química , Glucosídeos/isolamento & purificação , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Paquistão , Sitosteroides/química , Sitosteroides/isolamento & purificação , Tetra-Hidronaftalenos/química
14.
Fitoterapia ; 84: 202-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23103954

RESUMO

Seven constituents were isolated from the stems of Lawsonia alba Lam., following an activity-guided isolation, which include two new constituents, namely lawsorosemarinol (1) and lawsofructose (2), one known compound 2-(ß-d-glucopyranosyloxy)-1, 4-naphthoquinone (3) and four compounds, 4-hydroxy coumarine (4), 3-(4-hyroxyphenyl)-triacontyl-(Z)-propenoate (5), 3-(4-hydroxy-3-methoxyphenyl)-triacontyl-(Z)-propenoate (6) and 7-hydroxy-4-methyl coumarin (7) first time isolated from Lawsonia alba. Their structure elucidation was based on spectroscopic data analyses. Compounds 3 and 7 showed a moderate inhibition of urease activity, while rest of them showed less than 50% inhibition. These compounds did not show any significant inhibition against α-chymotrypsin.


Assuntos
Quimotripsina/antagonistas & inibidores , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Lawsonia (Planta)/química , Caules de Planta/química , Urease/antagonistas & inibidores , Quimotripsina/metabolismo , Estrutura Molecular , Estereoisomerismo , Urease/metabolismo
15.
Arch Pharm Res ; 35(3): 431-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22477189

RESUMO

A new C-alkylated flavonoid (5,7-dihydroxy-3'-(4″-acetoxy-3″-methylbutyl)-3,6,4'-trimethoxyflavone (1), along with two known C-alkylated flavonoids (5,7-dihydroxy-3'-(3-hydroxymethylbutyl)-3,6,4'-trimethoxyflavone (2), 5,7,4'-trihydroxy-3'-(3-hyroxymethylbutyl)-3,6-dimethoxyflavone (3) and two new source C-alkylated flavonoids (5,7-dihydroxy-3'-(2-hydroxy-3-methyl-3-butenyl)-3,6,4'-trimethoxyflavone (4), 5,7,4'-trihydroxy-3,6-dimethoxy-3'-isoprenyl-flavone (5) were isolated from the aerial parts of Dodonaea viscosa. The structures of all compounds were established on the basis of 1D and 2D NMR spectroscopy and mass spectrometry. The isolated compounds were evaluated for their inhibitory effect on urease and α-chymotrypsin enzyme. All the compounds (1-5) exhibited mild inhibition against urease but remained recessive in case of α-chymotrypsin.


Assuntos
Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Sapindaceae/química , Alquilação , Quimotripsina/antagonistas & inibidores , Inibidores Enzimáticos/química , Flavonoides/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Componentes Aéreos da Planta , Espectrometria de Massas por Ionização por Electrospray , Urease/antagonistas & inibidores
16.
Fitoterapia ; 83(1): 204-8, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22062354

RESUMO

Phytochemical investigation of the stem bark of Stereospermum acuminatissimum K. Schum. resulted in the isolation of 21 compounds, including two new guanine derivatives, 1,3,7-trimethylguanin-1/3-ium (1) and 3,7-dimethylguanin-1/3-ium (2), and one new phenolic long chain ester, 2-(4-hydroxyphenyl)ethyl hentriacontanoate (3). The known compounds were identified as sterequinones A, F, and H (4, 5, and 6), zenkequinones A-B (7-8), p-coumaric acid (9), methyl caffeate (10), caffeic acid (11), psilalic acid (12), syringaldehyde (13), norviburtinal (14), specioside (15), verminoside (16), tyrosol (17), eutigoside A (18), ellagic acid (19), atranorin (20), and ursolic acid (21). The metabolites were screened for their potential against urease and α-chymotrypsin enzymes, as urease is targeted in peptic ulcer while α-chymotrypsin is used to remove protein debris in ulcer. Compound 20 was found to be excellent urease inhibitor with IC(50) value of 18.2 ± 0.03 µM. Compounds 13 and 18-20 are reported for the first time from the genus Stereospermum. The chemotaxonomic significance of the isolated compounds was also described.


Assuntos
Antraquinonas/química , Antraquinonas/farmacologia , Bignoniaceae/química , Iridoides/química , Iridoides/farmacologia , Urease/antagonistas & inibidores , Antraquinonas/metabolismo , Bignoniaceae/metabolismo , Biomarcadores , Iridoides/metabolismo , Estrutura Molecular
17.
J Enzyme Inhib Med Chem ; 27(3): 348-55, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21774747

RESUMO

The biotransformation of dehydroepiandrosterone (1) with Macrophomina phaseolina was investigated. A total of eight metabolites were obtained which were characterized as androstane-3,17-dione (2), androst-4-ene-3,17-dione (3), androst-4-ene-17ß-ol-3-one (4), androst-4,6-diene-17ß-ol-3-one (5), androst-5-ene-3ß,17ß-diol (6), androst-4-ene-3ß-ol-6,17-dione (7), androst-4-ene-3ß,7ß,17ß-triol (8), and androst-5-ene-3ß,7α,17ß-triol (9). All the transformed products were screened for enzyme inhibition, among which four were found to inhibit the ß-glucuronidase enzyme, while none inhibited the α-chymotrypsin enzyme.


Assuntos
Ascomicetos/metabolismo , Desidroepiandrosterona/metabolismo , Desidroepiandrosterona/farmacologia , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Glucuronidase/antagonistas & inibidores , Biotransformação , Desidroepiandrosterona/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Glucuronidase/metabolismo , Conformação Molecular , Relação Estrutura-Atividade
18.
Nat Prod Commun ; 6(8): 1117-20, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21922913

RESUMO

Phytochemical investigation of the aerial parts of Cichorium intybus L. resulted in the isolation and identification of two new natural metabolites, 2,6-di[but-3(E)-en-2-onyl]naphthalene (1), and 3,3',4,4'-tetrahydroxychalcone (2), along with nine known compounds. Their structures were determined by spectroscopic techniques including 1D and 2D NMR. The known compounds were identified as scopoletin (3), 4-hydroxyphenylacetic acid (4), 3-hydroxy-4-methoxybenzoic acid (5), 4,4'-dihydroxychalcone (6), 6,7-dihydroxycoumarine (7), 1-triacontanol (8), lupeol (9), beta-sitosterol (10), and beta-sitosterol-3-O-beta-glucopyranoside (11). Compounds 4-6 and 8 are reported for the first time from C. intybus. Compounds 2 and 3 showed weak inhibitory activities against urease and alpha-chymotrypsin enzymes, respectively.


Assuntos
Quimotripsina/antagonistas & inibidores , Cichorium intybus/química , Inibidores Enzimáticos/farmacologia , Urease/antagonistas & inibidores , Inibidores Enzimáticos/química , Estrutura Molecular , Extratos Vegetais/química
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