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1.
Toxicon ; 238: 107566, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38151204

RESUMO

The presence of neurotoxin ß-N-Methylamino-L-alanine (BMAA) in the seeds of Cycas sphaerica is reported for first time. We developed a UPLC-MS/MS method for BMAA quantification by derivatizing with dansyl chloride. The method successfully differentiated L-BMAA from its structural isomer 2,4-diaminobutyric acid (DAB). The extracting mixture 0.1M TCA: ACN 4:1 v/v had a recovery level of >95%. The method is a high throughput sensitive chromatographic technique with 16.42 ng g-1 Limit of Quantification. BMAA was present in the endosperm of C. sphaerica, and was not detected in the leaves and pith. Washing of seeds in running cold water for 48 h reduced BMAA content by 86%. The local communities also treat the seeds under running cold water, but only for 24 h. The results of the study thus validated the traditional BMAA removal process through cold water treatment, but recommend for increase in the treatment period to 48 h or more.


Assuntos
Diamino Aminoácidos , Toxinas de Cianobactérias , Cycas , Espectrometria de Massas em Tandem/métodos , Cycas/química , Cromatografia Líquida/métodos , Espectrometria de Massa com Cromatografia Líquida , Diamino Aminoácidos/química , Neurotoxinas/análise
2.
Carbohydr Polym ; 261: 117831, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33766335

RESUMO

Arabinogalactan-proteins (AGPs), important signalling molecules of the plant cell wall, are structurally extensively investigated in angiosperms, but information on AGPs in gymnosperms is still limited. We characterized AGPs from the gymnosperms Ginkgo biloba, Ephedra distachya, Encephalartos longifolius and Cycas revoluta. The protein contents are comparable to that of angiosperm AGPs. Hydroxyproline is the site of linking the carbohydrate part and was detected in all AGPs with highest concentration in Cycas AGP (1.1 % of the AGP). Interestingly, with the exception of Cycas, all AGPs contained the monosaccharide 3-O-methylrhamnose not present in angiosperm polysaccharides. The carbohydrate moieties of Cycas and Ephredra showed the main components 1,3,6-linked galactose and terminal arabinose typical of angiosperm AGPs, whereas that of Ginkgo AGP was unique with 1,4-linked galactose as dominant structural element. Bioinformatic search for glycosyltransferases in Ginkgo genome also revealed a lower number of galactosyltransferases responsible for biosynthesis of the 1,3-Gal/1,6-Gal AGP backbone.


Assuntos
Parede Celular/química , Cycadopsida/química , Mucoproteínas/química , Evolução Biológica , Sequência de Carboidratos , Parede Celular/metabolismo , Biologia Computacional , Cycadopsida/classificação , Cycadopsida/metabolismo , Cycas/química , Cycas/metabolismo , Ephedra/química , Ephedra/metabolismo , Galactanos/química , Ginkgo biloba/química , Ginkgo biloba/metabolismo , Estrutura Molecular , Mucoproteínas/isolamento & purificação , Mucoproteínas/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Conformação Proteica , Zamiaceae/química , Zamiaceae/metabolismo
3.
J Sci Food Agric ; 101(4): 1530-1537, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32869314

RESUMO

BACKGROUND: Cycas circinalis leaves are used to treat diabetes mellitus in local medicinal systems without any scientifically proved information on their medicinal potential and phytochemicals. In this study, the total phenolic contents, total flavonoid contents, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging and inhibitory effects on α-glucosidase and α-amylase were determined for optimized hydroethanolic leaf extracts. Secondary metabolites were identified using ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS/MS). In vivo studies on diabetic albino mice were also carried out to evaluate the impact of the most active extract on their blood glucose levels. RESULTS: The 60% ethanolic extract showed the highest extract yield (209.70 ± 0.20 g kg-1 ) and total phenolic (154.24 ± 3.28 mg gallic acid equivalent) and flavonoid (78.52 ± 1.65 mg rutin equivalent per gram dried extract) contents and exhibited the maximum DPPH scavenging activity (IC50 = 59.68 ± 2.82 µg mL-1 ). The IC50 values for inhibition of α-glucosidase (58.42 ± 2.22 µg mL-1 ) and α-amylase (74.11 ± 1.70 µg mL-1 ) were also significant for the 60% ethanolic extract. The untargeted UHPLC-QTOF-MS/MS-based metabolite profiling confirmed the presence of iridoid glucoside, gibberellin A4, O-ß-d-glucosyl-4-hydroxy-cinnamate, 3-methoxy-2-phyenyl-4H-furo[2,3-h]chromen-4-one, kaempferol, withaferin A, amentoflavone, quercitin-3-O-(6″-malonyl glucoside), ellagic acid, and gallic acid. Plant extract at a dose of 500 mg kg-1 body weight reduced the blood glucose level by a considerable extent and also improved the lipid profile of diabetic mice after a 28-day trial. CONCLUSION: The findings revealed the medicinal potential of C. circinalis leaves to treat diabetes mellitus and provided the nutraceutical leads for functional food development. © 2020 Society of Chemical Industry.


Assuntos
Cycas/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Extratos Vegetais/administração & dosagem , Polifenóis/administração & dosagem , Animais , Glicemia/metabolismo , Cromatografia Líquida de Alta Pressão , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Experimental/genética , Feminino , Inibidores de Glicosídeo Hidrolases/administração & dosagem , Inibidores de Glicosídeo Hidrolases/química , Humanos , Hipoglicemiantes/química , Masculino , Espectrometria de Massas , Camundongos , Extratos Vegetais/química , Folhas de Planta/química , Polifenóis/química , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo
4.
Int J Biol Macromol ; 157: 743-751, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31805325

RESUMO

This study describes a sago starch-based film by incorporation of cinnamon essential oil (CEO) and nano titanium dioxide (TiO2-N). Different concentrations (i.e., 0%, 1%, 3%, and 5%, w/w) of TiO2-N and CEO (i.e., 0%, 1%, 2%, and 3%, v/w) were incorporated into sago starch film, and the physicochemical, barrier, mechanical, and antimicrobial properties of the bionanocomposite films were estimated. Incorporation of CEO into the sago starch matrix increased oxygen and water vapor permeability of starch films while increasing TiO2-N concentration decreased barrier properties. Moisture content also decreased from 12.96% to 8.04%, solubility in water decreased from 25% to 13.7%, and the mechanical properties of sago starch films improved. Sago starch bionanocomposite films showed excellent antimicrobial activity against Escherichia coli, Salmonella typhimurium, and Staphylococcus aureus. Results also showed that incorporation of TiO2-N and CEO had synergistic effects on functional properties of sago starch films. In summary, sago starch films incorporated with both TiO2-N and CEO shows potential application for active packaging in food industries such as fresh pistachio packaging.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Cinnamomum zeylanicum/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Amido/química , Titânio/química , Titânio/farmacologia , Materiais Biocompatíveis/química , Cycas/química , Membranas Artificiais , Testes de Sensibilidade Microbiana , Nanocompostos/química , Oxigênio/química , Permeabilidade , Solubilidade , Análise Espectral , Vapor , Resistência à Tração
5.
J Mater Sci Mater Med ; 30(10): 117, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31624921

RESUMO

The aim of this research was to formulate antimicrobial, composite films of guar gum, sago starch, and whey protein isolate for the prophylaxis of the bacterial gastroenteritis. The model antibacterial agents incorporated were essential oils, namely, carvacrol, citral and their combination. The films became darker and brownish in color due to the entrapment of the oils. The surface of the oil-entrapped films was more rough and coarse compared to the control film. Confocal micrographs affirmed the uniform distribution of the oil droplets within the biopolymeric network. The highest crystallite size and lowest lattice strain were estimated in the citral-containing film. FTIR analysis demonstrated that the incorporation of citral increased the proportion of the ß-sheet structures of the whey protein isolate within the film matrix. However, the film formulation containing combination of carvacrol and citral demonstrated the lowest water vapor transmission rate (WVTR), highest tensile strength, Young's modulus and work to failure. All the oil-containing films demonstrated good antibacterial potency against the model bacterial gastroenteritis causing bacteria, namely, Bacillus cereus and Escherichia coli. In gist, it can be concluded that the prepared antimicrobial films could be used for the prophylaxis of the bacterial gastroenteritis.


Assuntos
Monoterpenos Acíclicos/farmacologia , Antibacterianos/farmacologia , Cimenos/farmacologia , Galactanos/química , Mananas/química , Testes de Sensibilidade Microbiana , Gomas Vegetais/química , Amido/química , Proteínas do Soro do Leite/química , Bacillus cereus/efeitos dos fármacos , Cycas/química , Escherichia coli/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Teste de Materiais , Microscopia Confocal , Óleos Voláteis/química , Polímeros , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Estresse Mecânico , Resistência à Tração , Viscosidade , Difração de Raios X
6.
Pak J Pharm Sci ; 32(2 (Supplementary)): 871-874, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31103985

RESUMO

The leaves of Cycas revoluta were explored for their antioxidant, α-glucosidase and α-amylase inhibitory properties to develop safe and diet based therapeutic treatment of diabetes. In optimized fractionation, 60% ethanol provided the highest extract yield of 19.35±0.05a%, TPC 95.70±1.60a mg GAE/g and TFC 55 .60 ± 1.20a mg Rutin/g extract. The antioxidant and anti α-glucosidase activities of 60% ethanolic extracts were also promising and statistically significant as compared with remaining plant extracts. Ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-Q-TOF-MS/MS) analysis of the leaf extract revealed the presence of three apigenin derivatives, kaempferol derivative, hexadecenoic acid and citric acid. The binding energy values of molecular docking studies supported the synergistic behavior of leaf extract to inhibit α-glucosidase activity. The leaves of Cycas revoluta were proved to be apigenin rich natural pool of metabolites of antidiabetic importance to improvise food functionalities.


Assuntos
Antioxidantes/farmacologia , Cycas/metabolismo , Inibidores de Glicosídeo Hidrolases/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/metabolismo , Antioxidantes/química , Apigenina/análise , Cromatografia Líquida de Alta Pressão , Cycas/química , Avaliação Pré-Clínica de Medicamentos , Etanol , Inibidores de Glicosídeo Hidrolases/química , Simulação de Acoplamento Molecular , Extratos Vegetais/química , Plantas Medicinais/química , Plantas Medicinais/metabolismo , Espectrometria de Massas em Tandem , alfa-Amilases/antagonistas & inibidores
7.
World J Gastroenterol ; 25(15): 1854-1864, 2019 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-31057299

RESUMO

BACKGROUND: Gastric cancer is one of the most common and deadly malignancies worldwide. Despite recent medical progress, the 5-year survival rate of gastric cancer is still unsatisfactory. 5-fluorouracil (5-Fu) is one of the first-line antineoplastic treatments for gastric cancer, as it can effectively induce cancer cell apoptosis. However, the effect of 5-Fu is limited due to drug resistance of the malignant tumor. Previous studies have reported that Sotetsuflavone from Cycas revoluta Thunb. can markedly suppress lung cancer cell proliferation by apoptosis, though its effect on gastric cancer remains unknown. AIM: To investigate the inhibitory effect of Cycas revoluta Thunb. and to determine whether it can overcome gastric cancer cell drug resistance to 5-Fu. METHODS: Cell viability was examined to determine whether the natural extract of Cycas revoluta Thunb. induced gastric cancer cell death. The half-maximal effective concentration and the half-maximal lethal concentration were calculatede. Wound-healing and transwell assays were performed to examine gastric cancer cell motility. Clonogenic assays were performed to investigate the synergistic effects of Cycas revoluta Thunb. with 5-Fu, and apoptotic bodies were detected by Hoechst staining. Western blotting was performed to examine the expression of related proteins and to investigate the molecular mechanism of Cycas revoluta Thunb.-induced cancer cell apoptosis. The expressions of proteins, including mammalian target of rapamycin (mTOR) and p-AKT, were detected in different combinations of treatments for 48 h, then analyzed by ECL detection. RESULTS: Gastric cancer cells were more sensitive to the natural extract of Cycas revoluta Thunb. compared to normal gastric epithelial cells, and the extract effectively inhibited gastric cancer cell migration and invasion. The extract improved the anti-cancer effect of 5-Fu by enhancing the chemosensitization of gastric cancer cells. Extract plus 5-Fu further reduced the expression of the drug-resistance-related proteins p-AKT and mTOR after 48 h compared to 5-Fu alone. Compared to 5-Fu treatment alone, mTOR and p-AKT expression was significantly reduced by about 50% and 75%, respectively. We also found that the natural extract of Cycas revoluta Thunb. further increased 5-Fu-induced gastric cancer cell apoptosis. Expression of apoptosis-related protein X-linked inhibitor of apoptosis protein and apoptosis inducing factor were significantly reduced and increased, respectively, in the 5-Fu-resistant gastric cancer line SGC-7901/R treated with extract plus 5-Fu, while the expression of survivin did not change. CONCLUSION: The natural extract of Cycas revoluta Thunb. effectively inhibited gastric cancer cell growth and enhanced the anti-cancer effect of 5-Fu through the AKT-mTOR pathway.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Cycas/química , Medicamentos de Ervas Chinesas/farmacologia , Fluoruracila/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Fluoruracila/uso terapêutico , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/patologia , Serina-Treonina Quinases TOR/metabolismo
8.
Sci Rep ; 9(1): 4751, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30894551

RESUMO

Coralloid roots are specialized tissues of cycads (Cycas revoluta) that are involved in symbioses with nitrogen-fixing Nostoc cyanobacteria. We found that a crude methanolic extract of coralloid roots induced differentiation of the filamentous cell aggregates of Nostoc species into motile hormogonia. Hence, the hormogonium-inducing factor (HIF) was chased using bioassay-based isolation, and the active principle was characterized as a mixture of diacylglycerols (DAGs), mainly composed of 1-palmitoyl-2-linoleoyl-sn-glycerol (1), 1-palmitoyl-2-oleoyl-sn-glycerol (2), 1-stearoyl-2-linolenoyl-sn-glycerol (3), and 1-stearoyl-2-linoleoyl-sn-glycerol (4). Enantioselectively synthesised compound 1 showed a clear HIF activity at 1 nmol (0.6 µg) disc-1 for the filamentous cells, whereas synthesised 2-linoleoyl-3-palmitoyl-sn-glycerol (1') and 1-palmitoyl-2-linoleoyl-rac-glycerol (1/1') were less active than 1. Conversely, synthesised 1-linoleoyl-2-palmitoyl-rac-glycerol (8/8') which is an acyl positional isomer of compound 1 was inactive. In addition, neither 1-monoacylglycerols nor phospholipids structurally related to 1 showed HIF-like activities. As DAGs are protein kinase C (PKC) activators, 12-O-tetradecanoylphorbol-13-acetate (12), urushiol C15:3-Δ10,13,16 (13), and a skin irritant anacardic acid C15:1-Δ8 (14) were also examined for HIF-like activities toward the Nostoc cells. Neither 12 nor 13 showed HIF-like activities, whereas 14 showed an HIF-like activity at 1 nmol/disc. These findings appear to indicate that some DAGs act as hormogonium-inducing signal molecules for filamentous Nostoc cyanobacteria.


Assuntos
Cycas/química , Diglicerídeos/química , Nostoc/metabolismo , Extratos Celulares/química , Extratos Celulares/farmacologia , Diglicerídeos/isolamento & purificação , Nostoc/citologia , Nostoc/crescimento & desenvolvimento , Raízes de Plantas/química , Raízes de Plantas/microbiologia , Simbiose
9.
Toxicon ; 155: 49-50, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30316979

RESUMO

Cycad-associated neurodegenerative disease is more strongly correlated with the gymnosperm's major neurotoxin cycasin (methylazoxymethanol glucoside) than with the minor neurotoxin ß-N-methylamino-L-alanine (L-BMAA).


Assuntos
Diamino Aminoácidos/toxicidade , Acetato de Metilazoximetanol/análogos & derivados , Doenças Neurodegenerativas/induzido quimicamente , Encéfalo/efeitos dos fármacos , Toxinas de Cianobactérias , Cycas/química , Humanos , Acetato de Metilazoximetanol/toxicidade , Neurotoxinas/toxicidade
10.
J Insect Sci ; 18(5)2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30285257

RESUMO

The red palm weevil (RPW), Rhynchophorus ferrugineus Olivier (Coleoptera: Dryophthoridae) is one of the most dangerous pests of major cultivated palms including coconut, oil palm, and sago. The larval stage of the weevil causes the most destruction of the palms as it completely destroys the palm cabbage. In this study, the larvae were given three different diets-coconut cabbage, oil palm cabbage, and sago stem, under laboratory conditions for food consumption and developmental time experiment. The protein profiles of the digestive systems of the larvae fed on these three diets were also determined. Although the coconut diet was the most consumed by RPW larvae compared to oil palm and sago diets, the growth rate of RPW larvae on oil palm diet was however significantly shorter than those on the coconut and sago diets: the RPW only need 1 mo and 9 d to complete the larval duration. Proteins profiling of eight 2-DE gel protein spots that range 50-20 kDa were identified by mass spectrometry sequence analysis. Based on the Matrix Science Software, the most dominant protein was cationic trypsin. However, based on the NCBI BLAST tool, aminopeptidase N was the most dominant enzyme. This finding can lead to the development of pest control strategies based on the antinutritional protease inhibitors as potential biocontrol agents. Urgent action to find effective control methods should be taken seriously as this weevil is presumed to be one of the serious pests of oil palm industry in Malaysia.


Assuntos
Arecaceae/química , Cycas/química , Proteoma , Gorgulhos/fisiologia , Ração Animal/análise , Animais , Cocos/química , Dieta , Sistema Digestório/metabolismo , Comportamento Alimentar , Proteínas de Insetos/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Larva/fisiologia , Malásia , Gorgulhos/crescimento & desenvolvimento , Gorgulhos/metabolismo
11.
BMC Complement Altern Med ; 18(1): 235, 2018 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-30092797

RESUMO

BACKGROUND: Sotetsuflavone is isolated from Cycas revoluta Thunb., which has biological activity against tumors. However, the anti-proliferative effects of sotetsuflavone on A549 cells and its mechanism are not fully elucidated. METHODS: This study investigated the mechanisms of growth inhibition, cell cycle arrest and apoptosis in non-small cell lung cancer A549 cells induced by sotetsuflavone and evaluated whether sotetsuflavone can be safely utilized by humans as therapeutic agent. RESULTS: We found that sotetsuflavone had significant antiproliferative activity against A549 cells. At the same time, the reactive oxygen species (ROS) content increased while the mitochondrial membrane potential and the ratio of Bcl-2/Bax decreased. Cleaved caspase-3, cleaved caspase-9, cytochrome C and Bax expression increased, and Cyclin D1, CDK4, cleaved caspase-8 and Bcl-2 expression decreased. Interestingly, we demonstrated that sotetsuflavone could effectively inhibit the G0/G1 cycle progression, and then induce the endogenous apoptosis pathway. Our results show that sotetsuflavone could inhibit the growth of A549 cells by up-regulating intracellular ROS levels and causing the mitochondrial membrane potential to collapse, inducing G0/G1 phase arrest and endogenous apoptosis. CONCLUSIONS: In short, we confirm that sotetsuflavone had an inhibitory effect on A549 cells and discovered that it causes apoptosis of A549 lung cancer cells. Sotetsuflavone may be used as a novel candidate for anti-tumor therapy in patients with lung cancer.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Flavonas/farmacologia , Mitocôndrias/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Células A549 , Antineoplásicos/química , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cycas/química , Flavonas/química , Humanos , Extratos Vegetais/química
12.
Carbohydr Polym ; 180: 13-20, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29103489

RESUMO

Sago (Cycas circinalis) seed shells are agricultural waste materials discarded after taking the pith. In the present study Cellulose nanocrystals (CNCs) are isolated from the sago seed shells by acid hydrolysis. The hydrolysis was performed with 64% (w/w) sulphuric acid. The resulting CNCs were characterized by FTIR, XRD, SEM, TEM, AFM, DLS, Zeta (ζ) potential and TGA. FTIR spectrum of CNCs shows similar frequencies as that of α-cellulose, but with reduced intensity. XRD diffraction pattern shows co-existence of cellulose I and cellulose II with crystallinity index of 72% for cellulose II, 69% for cellulose I and crystallite size dimension of 9.4nm for cellulose I. SEM analysis clearly reveals the considerable size reduction during acid hydrolysis. TEM analysis shows that the isolated CNCs contain networked structures and almost spherical shaped particles having 10-15nm in size. Morphological examination through AFM also shows that isolated CNCs are in nano dimensions, having the size ∼50nm. DLS analysis gives an average size of 50nm and zeta (ζ) potential measured has a value of -37.8mV. DLS and AFM analyses support each other. TGA reveals lower thermal stability for CNCs.


Assuntos
Celulose/análogos & derivados , Cycas/química , Nanopartículas/química , Sementes/química
13.
Phytochemistry ; 144: 271-281, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29102875

RESUMO

The isolation of α-amino-ß-methylaminopropionic acid from seeds of Cycas circinalis (now C. micronesica Hill) resulted from a purposeful attempt to establish the cause of the profound neurological disease, amyotrophic lateral sclerosis/parkinsonism/dementia, that existed in high frequency amongst the inhabitants of the western Pacific island of Guam (Guam ALS/PD). In the 50 years since its discovery the amino acid has been a stimulus, and sometimes a subject of mockery, for generations of scientists in a remarkably diverse range of subject areas. The number of citations of the original paper has risen in the five decades from a few to 120 within the decade 2007-2016 and continues at a high rate into the next decade. The reasons for this remarkable outcome are discussed and examples from the literature are used to illustrate the wide range of scientific interest that the original paper generated.


Assuntos
Diamino Aminoácidos/efeitos adversos , Esclerose Lateral Amiotrófica/induzido quimicamente , Demência/induzido quimicamente , Transtornos Parkinsonianos/induzido quimicamente , Diamino Aminoácidos/química , Diamino Aminoácidos/isolamento & purificação , Esclerose Lateral Amiotrófica/patologia , Animais , Toxinas de Cianobactérias , Cycas/química , Demência/patologia , Guam , Humanos , Estrutura Molecular , Transtornos Parkinsonianos/patologia , Sementes/química
14.
Phytochemistry ; 144: 253-270, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29059579

RESUMO

The non-encoded diaminomonocarboxylic acids, 3-N-methyl-2,3-diaminopropanoic acid (syn: α-amino-ß-methylaminopropionic acid, MeDAP; ß-N-methylaminoalanine, BMAA) and 2,4-diaminobutanoic acid (2,4-DAB), are distributed widely in cyanobacterial species in free and bound forms. Both amino acids are neurotoxic in whole animal and cell-based bioassays. The biosynthetic pathway to 2,4-DAB is well documented in bacteria and in one higher plant species, but has not been confirmed in cyanobacteria. The biosynthetic pathway to BMAA is unknown. This review considers possible metabolic routes, by analogy with reactions used in other species, by which these amino acids might be biosynthesised by cyanobacteria, which are a widespread potential environmental source of these neurotoxins. Where possible, the gene expression that might be implicated in these biosyntheses is discussed.


Assuntos
Aminobutiratos/metabolismo , Produtos Biológicos/metabolismo , Cianobactérias/metabolismo , Neurotoxinas/metabolismo , Propionatos/metabolismo , Aminobutiratos/química , Animais , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Ácidos Carboxílicos/química , Ácidos Carboxílicos/isolamento & purificação , Cianobactérias/química , Cycas/química , Cycas/metabolismo , Diaminas/química , Diaminas/isolamento & purificação , Humanos , Estrutura Molecular , Neurotoxinas/química , Propionatos/química , Sementes/química , Sementes/metabolismo , Soluções
15.
J Oleo Sci ; 65(4): 283-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27041513

RESUMO

Oil palm empty fruit bunch (EFB) is one of the solid wastes produced in huge volume by palm oil mill. Whilst it still contains valuable oil, approximately 22.6 million tons is generated annually and treated as solid waste. In this work, sub-critical water (sub-cw) was used to extract oil, sugar and tar from spikelet of EFB. The spikelet was treated with sub-cw between 180-280°C and a reaction time of 2 and 5 minutes. The highest yield of oil was 0.075 g-oil/g-dry EFB, obtained at 240°C and reaction time of 5 minutes. Astonishingly, oil that was extracted through this method was 84.5% of that obtained through Soxhlet method using hexane. Yield of oil extracted was strongly affected by the reaction temperature and time. Higher reaction temperature induces the dielectric constant of water towards the non-polar properties of solvent; thus increases the oil extraction capability. Meanwhile, the highest yield of sugar was 0.20 g-sugar/g-dry EFB obtained at 220°C. At this temperature, the ion product of water is high enough to enable maximum sub-critical water hydrolysis reaction. This study showed that oil and other valuable material can be recovered using water at sub-critical condition, and most attractive without the use of harmful organic solvent.


Assuntos
Cycas/química , Frutas/química , Óleos de Plantas/isolamento & purificação , Eliminação de Resíduos/métodos , Resíduos Sólidos/análise , Água , Sacarose Alimentar/isolamento & purificação , Hidrólise , Organofosfatos/isolamento & purificação , Óleo de Palmeira , Alcatrões/isolamento & purificação , Temperatura , Fatores de Tempo
16.
J Biochem ; 160(1): 27-35, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26867733

RESUMO

Cycas revoluta leaf lectin (CRLL) of mannose-recognizing jacalin-related lectin (mJRL) has two tandem repeated carbohydrate recognition domains, and shows the characteristic sugar-binding specificity toward high mannose-glycans, compared with other mJRLs. We expressed the N-terminal domain and C-terminal domain (CRLL-N and CRLL-C) separately, to determine the fine sugar-binding specificity of each domain, using frontal affinity chromatography, glycan array and equilibrium dialysis. The specificity of CRLL toward high mannose was basically derived from CRLL-N, whereas CRLL-C had affinity for α1-6 extended mono-antennary complex-type glycans. Notably, the affinity of CRLL-N was most potent to one of three Man 8 glycans and Man 9 glycan, whereas the affinity of CRLL-C decreased with the increase in the number of extended α1-2 linked mannose residue. The recognition of the Man 8 glycans by CRLL-N has not been found for other mannose recognizing lectins. Glycan array reflected these specificities of the two domains. Furthermore, it was revealed by equilibrium dialysis method that the each domain had two sugar-binding sites, similar with Banlec, banana mannose-binding Jacalin-related lectin.


Assuntos
Cycas/química , Lectinas de Ligação a Manose/química , Folhas de Planta/química , Lectinas de Plantas/química
17.
Zhong Yao Cai ; 38(3): 481-4, 2015 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-26495646

RESUMO

OBJECTIVE: To detect flavonoids from Cycas revoluta leaves by means of Chemiluminescence-Flow Injection Analysis (CL-FIA). METHODS: Under alkaline condition, a CL-FIA method was established to determine flavonoids from leaves of Cycas revoluta on the basis of inhibiting effect of flavonoids to the Luminol-H2O2-Cu2+ chemiluminescence system and the reversed flow injection technique. RESULTS: In the range of 2. 0 x 10(-6) ~ 1. 0 x 10(-3) mg/mL, the decrease of CL intensity was correlated with flavonoids concentration while the detection limit was 0. 0265 µg/mL. Under the optimized conditions, the flavonoids of Cycas revoluta leaves were detected with its average rate reaching 1. 61% and RSD 1. 32%. CONCLUSION: Through the interference test and compared with the data of CL-FIA and UV, it is concluded that CL-FIA can be used in the analysis and detection of flavonoids from Cycas revoluta leaves.


Assuntos
Cycas/química , Flavonoides/análise , Folhas de Planta/química , Análise de Injeção de Fluxo , Limite de Detecção , Medições Luminescentes , Luminol
18.
Anal Bioanal Chem ; 407(28): 8397-409, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26396078

RESUMO

The neurotoxin ß-N-methylamino-L-alanine (BMAA) has been reported in cyanobacteria and shellfish, raising concerns about widespread human exposure. However, inconsistent results for BMAA analysis have led to controversy. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is the most appropriate method for analysis of BMAA, but the risk of interference from isomers, other sample components, and the electrospray background is still present. We have investigated differential mobility spectrometry (DMS) as an ion filter to improve selectivity in the hydrophilic interaction liquid chromatographic (HILIC)-MS/MS determination of BMAA. We obtained standards for two BMAA isomers not previously analyzed by HILIC-MS, ß-amino-N-methylalanine and 3,4-diaminobutanoic acid, and the typically used 2,4-diaminobutanoic acid and N-(2-aminoethyl)glycine. DMS separation of BMAA from these isomers was achieved and optimized conditions were used to develop a sensitive and highly selective multidimensional HILIC-DMS-MS/MS method. This work revealed current technical limitations of DMS for trace quantitation, and practical solutions were implemented. Accurate control of low levels of DMS carrier gas modifier was essential, but required external metering. The linearity of our optimized method was excellent from 0.01 to 6 µmol L(-1). The instrumental LOD was 0.4 pg BMAA injected on-column and the estimated method LOD was 20 ng g(-1) dry weight for BMAA in sample matrix. The method was used to analyze cycad plant tissue, a cyanobacterial reference material, and mussel tissues, by use of isotope-dilution quantitation with deuterated BMAA. This confirmed the presence of BMAA and several of its isomers in cycad and mussel tissues, including commercially available mussel tissue reference materials certified for other biotoxins. Graphical Abstract Differential Mobility Spectrometry is used to increases the selectivity of BMAA analysis by HILIC-MS/MS.


Assuntos
Diamino Aminoácidos/análise , Cromatografia Líquida/normas , Contaminação de Alimentos , Neurotoxinas/análise , Espectrometria de Massas em Tandem/normas , Aminobutiratos/análise , Animais , Bivalves/química , Bivalves/metabolismo , Calibragem , Cromatografia Líquida/métodos , Cianobactérias/química , Cianobactérias/metabolismo , Toxinas de Cianobactérias , Cycas/química , Cycas/metabolismo , Glicina/análogos & derivados , Glicina/análise , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Padrões de Referência , Espectrometria de Massas em Tandem/métodos
19.
Environ Sci Pollut Res Int ; 22(21): 16943-50, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26109223

RESUMO

Malaysia is one of the highest starch producers. In this study, sago starch was utilized as a natural coagulant aid to reduce the dosage of aluminum-based coagulant in leachate treatment. The potential of native sago trunk starch (NSTS) and commercial sago starch (CSS) was evaluated as sole coagulant and coagulant aid in the presence of polyaluminum chloride (PACl) in the removal of color, suspended solids (SS), NH3-N, turbidity, chemical oxygen demand, organic UV254, Cd, and Ni. Leachate was sampled from Pulau Burung Landfill Site, one of the semi-aerobic landfills in Malaysia. The optimum dosage for PACl in the presence of NSTS or CSS as coagulant aid was reduced from 3100 to 2000 mg/L. In the presence of 2000 mg/L PACl with 6000 mg/L NSTS and 2000 mg/L PACl with 5000 mg/L CSS, the removal performance for color, SS, and turbidity are 94.7, 99.2, and 98.9%, respectively. Similar results were obtained with the use of 3100 mg/L PACl alone. Therefore, CSS and NSTS can be used as coagulant aid.


Assuntos
Coagulantes , Cycas/química , Amido , Poluentes Químicos da Água , Purificação da Água , Coagulantes/química , Coagulantes/isolamento & purificação , Amido/química , Amido/isolamento & purificação , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
20.
Phytomedicine ; 22(1): 23-6, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25636866

RESUMO

Bioactivity guided chemical investigation on active anti-diabetic constituents of the fruits of Cycas pectinata Griff. (FCP) characterized EAFr-5 as the most potent sub fraction which significantly reduced the blood glucose level to normal in STZ induced diabetic rats. It was shown to contain the biflavonoids amentoflavone (1) and 2,3-dihydroamentoflavone (2) which exhibited significantly high inhibitory potency against α-glucosidase (IC50 8.09 ± 0.023 and 9.77 ± 0.032 µM, respectively) and α-amylase (IC50 73.6 ± 0.48 and 39.69 ± 0.39 µM, respectively). This is the first report of bioactivity guided isolation of anti-diabetic constituents from the traditionally used fruits of Cycas pectinata Griff.


Assuntos
Biflavonoides/farmacologia , Cycas/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Animais , Biflavonoides/metabolismo , Frutas/química , Concentração Inibidora 50 , Estrutura Molecular , Ratos Wistar , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo , alfa-Glucosidases/metabolismo
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