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1.
Chem Biodivers ; 20(8): e202300249, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37318911

RESUMO

The study presents antioxidant, phytochemical, anti-proliferative, and gene repression activities against Hypoxia-inducible factor (HIF-1) alpha and Vascular endothelial growth factor (VEGF) of Elaeocarpus sphaericus extract. Elaeocarpus sphaericus dried and crushed plant leaves were extracted using water and methanol by ASE (Accelerated Solvent Extraction) method. Total phenolic content (TPC) and total flavonoid content (TFC) were used to measure the extracts' phytochemical activity (TFC). Antioxidant potential of the extracts was measured through DPPH, ABTS, FRAP, and TRP. Methanolic extract of the leaves of E. sphaericus has shown a higher amount of TPC (94.666±4.040 mg/gm GAE) and TFC value (172.33±3.21 mg/gm RE). The antioxidant properties of extracts in the yeast model (Drug Rescue assay) showed promising results. Ascorbic acid, gallic acid, hesperidin, and quercetin were found in the aqueous and methanolic extracts of E. sphaericus at varying amounts, according to a densiometric chromatogram generated by HPTLC analysis. Methanolic extract of E. sphaericus (10 mg/ml) has shown good antimicrobial potential against all bacterial strains used in the study except E. coli. The anticancer activity of the extract in HeLa cell lines ranged from 77.94±1.03 % to 66.85±1.95 %, while it ranged from 52.83±2.57 % to 5.44 % in Vero cell lines at varying concentration (1000 µg/ml-31.2 µg/ml). A promising effect of extract was observed on the expression activity of HIF-1 and VEGF gene through RT-PCR assay.


Assuntos
Antioxidantes , Elaeocarpaceae , Humanos , Antioxidantes/química , Fator A de Crescimento do Endotélio Vascular/genética , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Células HeLa , Escherichia coli , Flavonoides/análise , Metanol , Fenóis/farmacologia , Fenóis/análise , Compostos Fitoquímicos
2.
Biotechnol Prog ; 33(1): 70-80, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27689686

RESUMO

Chitinase from the thermophilic mould Myceliopthora thermophila BJA (MtChit) is an acid tolerant, thermostable and organic solvent stable biocatalyst which does not require any metal ions for its activity. To produce high enzyme titres, reduce fermentation time and overcome the need for induction, this enzyme has been heterologously expressed under GAP promoter in the GRAS yeast, Pichia pastoris. The production medium supplemented with the permeabilizing agent Tween-20 supported two-fold higher rMtChit production (5.5 × 103 U L-1 ). The consensus sequences S(132)xG(133)G(134) and D(168)xxD(171)xD(173)xE(175) in the enzyme have been found to represent the substrate binding and catalytic sites, respectively. The rMtChit, purified to homogeneity by a two-step purification strategy, is a monomeric glycoprotein of ∼48 kDa, which is optimally active at 55°C and pH 5.0. The enzyme is thermostable with t1/2 values of 113 and 48 min at 65 and 75°C, respectively. Kinetic parameters Km , Vmax , kcat , and kcat /Km of the enzyme are 4.655 mg mL-1 , 34.246 nmol mg-1  s-1 , 3.425 × 106 min-1 , and 1.36 × 10-6 mg mL-1  min-1 , respectively. rMtChit is an unique exochitinase, since its action on chitin liberates N-acetylglucosamine NAG. The enzyme inhibits the growth of phytopathogenic fungi like Fusarium oxysporum and Curvularia lunata, therefore, this finds application as biofungicide at high temperatures during summer in tropics. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:70-80, 2017.


Assuntos
Acetilglucosamina/biossíntese , Fungos/crescimento & desenvolvimento , Hexosaminidases/biossíntese , Proteínas Recombinantes/biossíntese , Quitina/biossíntese , Quitina/metabolismo , Fermentação , Fungos/patogenicidade , Hexosaminidases/genética , Cinética , Pichia/genética , Proteínas Recombinantes/genética , Sordariales/enzimologia , Sordariales/genética , Especificidade por Substrato
3.
Nat Prod Res ; 31(12): 1468-1471, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27868445

RESUMO

In this study, we report the in vitro anti-HIV1 activity of acetone and methanol extracts of fruit of Terminalia paniculata. Cytotoxicity tests were conducted on TZM-bl cells and peripheral blood mononuclear cells (PBMC), the CC50 values of both the extracts were ≥260 µg/mL. Using TZM-bl cells, the extracts were tested for their ability to inhibit replication of two primary isolates HIV-1 (X4, Subtype D) and HIV-1 (R5, Subtype C). The activity against HIV-1 primary isolate (R5, Subtype C) was confirmed using activated PBMC and by quantification of HIV-1 p24 antigen. Both the extracts showed anti-HIV1 activity in a dose-dependent manner. The EC50 values of the acetone and methanol extracts of T. paniculata were ≤10.3 µg/mL. The enzymatic assays were performed to determine the mechanism of action which indicated that the anti-HIV1 activity might be due to inhibition of reverse transcriptase (≥77.7% inhibition) and protease (≥69.9% inhibition) enzymes.


Assuntos
Fármacos Anti-HIV/farmacologia , HIV-1/efeitos dos fármacos , Extratos Vegetais/farmacologia , Terminalia , Frutas , Humanos
4.
Appl Biochem Biotechnol ; 176(5): 1351-69, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25957272

RESUMO

The phytase of the yeast Pichia anomala is a histidine acid phosphatase based on signature sequences and catalytic amino acids identified by site-directed mutagenesis. Among modulators, N-bromosuccinimide and butanedione inhibit phytase, while Ca(2+) and Ni(2+) stimulate slightly. Vanadate exhibits competitive inhibition of phytase, making it bifunctional to act as haloperoxidase. Molecular docking supports vanadate to share its binding site with phytate. The T 1/2, activation energy (E a ), temperature quotient (Q 10), activation energy of thermal inactivation (Ed), and enthalpy (ΔH d (0) ) of the enzyme are 4.0 min (80 °C), 27.72 kJ mol(-1), 2.1, 410.62 kJ mol(-1), and ∼407.8 kJ mol(-1) (65-80 °C), respectively. The free energy of the process (ΔG d (o) ) increases from 49.56 to 71.58 kJ mol(-1) with rise in temperature, while entropy of inactivation (ΔS d (0) ) remains constant at ∼1.36 kJ mol(-1) K(-1). The supplementation of whole wheat dough with rPPHY resulted in 72.5 % reduction in phytic acid content of bread. These characteristics confirm that the phytase has adequate thermostability for its applicability as a food and feed additive.


Assuntos
6-Fitase/metabolismo , Peroxidase/biossíntese , Pichia/enzimologia , 6-Fitase/antagonistas & inibidores , 6-Fitase/química , 6-Fitase/genética , Sequência de Aminoácidos , Biocatálise/efeitos dos fármacos , Pão , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Mutação/genética , Peroxidase/metabolismo , Desnaturação Proteica/efeitos dos fármacos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Tartaratos/farmacologia , Temperatura de Transição , Triticum , Vanadatos/farmacologia
5.
Nat Prod Res ; 29(22): 2080-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25643642

RESUMO

Phytochemical investigation of the methanol extract of the aerial parts of Polygonum glabrum afforded one new natural product (-)-2-methoxy-2-butenolide-3-cinnamate (1) along with six known compounds, ß-hydroxyfriedalanol (2), 3-hydroxy-5-methoxystilbene (3), (-) pinocembrin (4), sitosterol-(6'-O-palmitoyl)-3-O-ß-D-glucopyranoside (5), (-) pinocembrin-5-methyl ether (6) and sitosterol-3-O-ß-D-glucopyranoside (7). Compound 1 showed promising in vitro anti-HIV-1 activity against primary isolates HIV-1(UG070) (X4, subtype D) and HIV-1(VB59) (R5, subtype C) assayed using TZM-bl cell line with IC50 in the range of 15.68-22.43 µg/mL. The extract showed TI in the range of 19.19-27.37 with IC50 in the range of 10.90-15.55 µg/mL. Compounds 1, 3 and 4 exhibited in vitro anti-mycobacterium activity against Mycobacterium tuberculosis H37Ra with IC50 values of 1.43, 3.33 and 1.11 µg/mL in dormant phase and 2.27, 3.33 and 1.21 µg/mL in active phase, respectively. Compound 4 was found to be the most active antiproliferative with IC50 values of 1.88-11.00 µg/mL against THP-1, A549, Panc-1, HeLa and MCF7 cell lines.


Assuntos
4-Butirolactona/análogos & derivados , Cinamatos/química , Extratos Vegetais/química , Polygonum/química , 4-Butirolactona/química , 4-Butirolactona/isolamento & purificação , Antibacterianos/química , Antibacterianos/isolamento & purificação , Fármacos Anti-HIV/química , Fármacos Anti-HIV/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Cinamatos/isolamento & purificação , HIV-1/efeitos dos fármacos , Humanos , Estrutura Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Componentes Aéreos da Planta/química
6.
Nat Prod Res ; 29(16): 1562-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25427632

RESUMO

Comprehensive management of sexually transmitted infections (STIs) using vaginal or rectal microbicide-based intervention is one of the strategies for prevention of HIV infection. Herbal products have been used for treating STIs traditionally. Herein, we present in vitro activity of 10 plant extracts and their 34 fractions against three sexually transmitted/reproductive tract pathogens - Neisseria gonorrhoeae, Haemophilus ducreyi and Candida albicans. The plant parts were selected; the extracts/fractions were prepared and screened by disc diffusion method. The minimum inhibitory and minimum cidal concentrations were determined. The qualitative phytochemical analysis of selected extracts/fractions showing activity was performed. Of the extracts/fractions tested, three inhibited C. albicans, ten inhibited N. gonorrhoeae and five inhibited H. ducreyi growth. Our study demonstrated that Terminalia paniculata Roth. extracts/fractions inhibited growth of all three organisms. The ethyl acetate fraction of Syzygium cumini Linn. and Bridelia retusa (L.) Spreng. extracts was found to inhibit N. gonorrhoeae at lowest concentrations.


Assuntos
Anti-Infecciosos/farmacologia , Candida albicans/efeitos dos fármacos , Haemophilus ducreyi/efeitos dos fármacos , Neisseria gonorrhoeae/efeitos dos fármacos , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana , Syzygium/química , Terminalia/química
7.
Nat Prod Res ; 28(4): 245-50, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24099509

RESUMO

From the red coloured extract (Kamala) prepared through acetone extraction of the fresh whole uncrushed fruits of Mallotus philippinensis, one new dimeric chalcone (1) along with three known compounds 1-(5,7-dihydroxy-2,2,6-trimethyl-2H-1-benzopyran-8-yl)-3-phenyl-2-propen-1-one (2), rottlerin (3) and 4'-hydroxyrottlerin (4) were isolated. The structure of compound 1 was elucidated by 1D and 2D NMR analyses that included HSQC, HMBC, COSY and ROESY experiments along with the literature comparison. Compounds 1-4 were evaluated for antifungal activity against different human pathogenic yeasts and filamentous fungi. The antiproliferative activity of the compounds was evaluated against Thp-1 cell lines. Compounds 1 and 2 both exhibited IC50 of 8, 4 and 16 µg/mL against Cryptococcus neoformans PRL518, C. neoformans ATCC32045 and Aspergillus fumigatus, respectively. Compound 4, at 100 µg/mL, showed 54% growth inhibition of Thp-1 cell lines.


Assuntos
Antifúngicos , Chalcona , Euphorbiaceae/química , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Chalcona/análogos & derivados , Chalcona/química , Chalcona/isolamento & purificação , Chalcona/farmacologia , Chalconas , Cryptococcus neoformans/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Frutas/química , Fungos/efeitos dos fármacos , Humanos , Índia , Concentração Inibidora 50 , Leucemia/tratamento farmacológico , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Extratos Vegetais/química , Leveduras/efeitos dos fármacos
8.
Artigo em Chinês | WPRIM | ID: wpr-951836

RESUMO

Objective: To evaluate the antiplasmodial properties of fractions of chloroform portion of Phyllanthus niruri (P. niruri) methanol extract and identify a suitable chemical marker present therein. Methods: Chloroform portion of P. niruri methanol extract was separated from silica gel using gradient systems of hexane, ethylacetate and methanol. The fractions were screened for antiplasmodial activity against Plasmodium falciparum HB3 and FcM29. Fractions with IC

9.
Nat Prod Res ; 27(20): 1896-901, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23577701

RESUMO

A new dipyranocoumarin, α-hydroxytomentolide A (1) was isolated from the leaves of Calophyllum apetalum together with the known compounds friedelin (2), apetalactone (3), inophyllum C (4) and canophyllol (5). The structure of the new compound was established by spectroscopic studies which include (1)H NMR, (13)C NMR, NOESY, HetCOSY, COLOC experiments and single crystal X-ray diffraction analysis.


Assuntos
Calophyllum/química , Cumarínicos/isolamento & purificação , Extratos Vegetais/análise , Folhas de Planta/química , Cumarínicos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Difração de Raios X
10.
Indian J Exp Biol ; 42(1): 91-5, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15274488

RESUMO

Extracts and purified extracts of seeds of two plant species, Madhuca latifolia and Calophyllum inophyllum when evaluated against the 2nd instar larvae of Helicoverpa armigera reared on synthetic diet, exhibited high larval mortality, prolongation of developmental period, morphological deformities and highly significant reduction in adult emergence. The reduction in larval weights in the treatments was also highly significant.


Assuntos
Extratos Vegetais , Sementes/metabolismo , Animais , Peso Corporal , Relação Dose-Resposta a Droga , Larva/metabolismo , Mariposas , Controle Biológico de Vetores , Sementes/microbiologia , Temperatura , Fatores de Tempo
11.
J Commun Dis ; 34(2): 88-99, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-14768825

RESUMO

The in-vitro antiviral activity of a series of compounds in samples extracted from various parts of the Indian holy tree, Bael (Aegle marmelos corr.) were evaluated for their efficacy against human coxsackieviruses B1-B6. The inhibitory concentrations (IC50) for leaves (L1 and L2) stem and stem bark (S1, S2, S3 and S4) fruit (F1 and F2micro) root and root bark (R1 and R2) and pure compound, the marmelide were 1000 microg/ml (for L1 and L2), 1000 microg/ml (for S1, S2, S3 and S4), 1000 microg/ml (for F1) and 500 microg/ml (for F2) 250 microg/ml (for R1) and 500 microg/ml (for R2) and 62.5 microg/ml for marmelide respectively by plaque inhibition assay at 96 hrs. On the other hand, the corresponding value for Ribavirin, a standard antiviral drug, was 2000 microg/ml for the same viruses at the same time period. These concentrations did not exhibit any toxicity to Vero cells, the host subtoxic concentrations were 5000 microg/ml for leaf and stem fractions 2000 microg/ml for fruit fractions 500 and 1000 microg/ml for root fractions 250 microg/ml for marmelide and 2000 microg/ml for Ribavirin. The cytotoxic concentrations were 8000 microg/ml for leaf and stem compounds 4000 mg/ml for fruit; 1000 microg/ml and 2000 microg/ml for root 500 microg/ml for marmelide and 4000 microg/ml for ribavirin at 96 hrs. These were also confirmed by trypan blue dye exclusion test and further passaging of cells. Additionally pretreatment of host cells, virus inactivation, yield reduction and effect of time of addition assays against coxsackievirus B3 suggested that marmelide was most effective as a virucidal agent besides interfering at early events of its replicative cycle like adsorption, penetration, at various steps in single cycle growth curve and effect of time of addition.


Assuntos
Aegle , Antivirais/farmacologia , Cumarínicos/farmacologia , Enterovirus Humano B/efeitos dos fármacos , Furanos/farmacologia , Preparações de Plantas/farmacologia , Ribavirina/farmacologia , Antivirais/química , Antivirais/isolamento & purificação , Cumarínicos/química , Cumarínicos/isolamento & purificação , Furanos/química , Furanos/isolamento & purificação , Humanos
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