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1.
PLoS One ; 19(6): e0304701, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38870120

RESUMO

This paper presents the initial exploration of the free radical scavenging capabilities of peptides derived from protein hydrolysates (PPH) obtained from Zingiber cassumunar rhizomes (Phlai). To replicate the conditions of gastrointestinal digestion, a combination of pepsin and pancreatin proteolysis was employed to generate these hydrolysates. Subsequently, the hydrolysate underwent fractionation using molecular weight cut-off membranes at 10, 5, 3, and 0.65 kDa. The fraction with a molecular weight less than 0.65 kDa exhibited the highest levels ABTS, DPPH, FRAP, and NO radical scavenging activity. Following this, RP-HPLC was used to further separate the fraction with a molecular weight less than 0.65 kDa into three sub-fractions. Among these, the F5 sub-fraction displayed the most prominent radical-scavenging properties. De novo peptide sequencing via quadrupole-time-of-flight-electron spin induction-mass spectrometry identified a pair of novel peptides: Asp-Gly-Ile-Phe-Val-Leu-Asn-Tyr (DGIFVLNY or DY-8) and Ile-Pro-Thr-Asp-Glu-Lys (IPTDEK or IK-6). Database analysis confirmed various properties, including biological activity, toxicity, hydrophilicity, solubility, and potential allergy concerns. Furthermore, when tested on the human adenocarcinoma colon (Caco-2) cell line, two synthetic peptides demonstrated cellular antioxidant activity in a concentration-dependent manner. These peptides were also assessed using the FITC Annexin V apoptosis detection kit with PI, confirming the induction of apoptosis. Notably, the DY-8 peptide induced apoptosis, upregulated mRNA levels of caspase-3, -8, and -9, and downregulated Bcl-2, as confirmed by real-time quantitative polymerase chain reaction (RT-qPCR). Western blot analysis indicated increased pro-apoptotic Bax expression and decreased anti-apoptotic Bcl-2 expression in Caco-2 cells exposed to the DY-8 peptide. Molecular docking analysis revealed that the DY-8 peptide exhibited binding affinity with Bcl-2, Bcl-xL, and Mcl-1, suggesting potential utility in combating colon cancer as functional food ingredients.


Assuntos
Apoptose , Neoplasias do Colo , Peptídeos , Rizoma , Transdução de Sinais , Humanos , Apoptose/efeitos dos fármacos , Rizoma/química , Células CACO-2 , Transdução de Sinais/efeitos dos fármacos , Peptídeos/farmacologia , Peptídeos/química , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Neoplasias do Colo/metabolismo , Zingiberaceae/química , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/química
2.
PLoS One ; 19(5): e0301966, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38776280

RESUMO

The purpose of this study is to assess the bioactive peptides derived from the defatted lemon basil seeds hydrolysate (DLSH) for their ability to inhibit pancreatic lipase, decrease intracellular lipid accumulation, and reduce adipogenesis. Response surface methodology (RSM) was employed to optimize trypsin hydrolysis conditions for maximizing lipase inhibitory activity (LI). A hydrolysis time of 387.06 min, a temperature of 49.03°C, and an enzyme concentration of 1.61% w/v, resulted in the highest LI with an IC50 of 368.07 µg/mL. The ultrafiltration of the protein hydrolysate revealed that the fraction below 0.65kDa exhibited the greatest LI potential. Further purification via RP-HPLC identified the Gly-Arg-Ser-Pro-Asp-Thr-His-Ser-Gly (GRSPDTHSG) peptide in the HPLC fraction F1 using mass spectrometry. The peptide was synthesized and demonstrated LI with an IC50 of 0.255 mM through a non-competitive mechanism, with a constant (Ki) of 0.61 mM. Docking studies revealed its binding site with the pancreatic lipase-colipase complex. Additionally, GRSPDTHSG inhibited lipid accumulation in 3T3-L1 cells in a dose-dependent manner without cytotoxic effects. Western blot analysis indicated downregulation of PPAR-γ and SREBP-1c levels under GRSPDTHSG treatment, while an increase in AMPK-α phosphorylation was observed, suggesting a role in regulating cellular lipid metabolism. Overall, GRSPDTHSG demonstrates potential in attenuating lipid absorption and adipogenesis, suggesting a prospective application in functional foods and nutraceuticals.


Assuntos
Células 3T3-L1 , Adipócitos , Adipogenia , Lipase , Ocimum basilicum , PPAR gama , Peptídeos , Sementes , Proteína de Ligação a Elemento Regulador de Esterol 1 , Camundongos , Animais , Adipogenia/efeitos dos fármacos , Sementes/química , PPAR gama/metabolismo , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Hidrólise , Lipase/antagonistas & inibidores , Lipase/metabolismo , Peptídeos/farmacologia , Peptídeos/química , Peptídeos/isolamento & purificação , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Ocimum basilicum/química , Regulação para Baixo/efeitos dos fármacos , Simulação de Acoplamento Molecular
3.
Talanta ; 273: 125911, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38508129

RESUMO

Lateral flow immunoassays (LFIAs) are widely used to determine carbendazim (CBZ) residues in food products due to their advantages of low cost, ease and rapid use, on-site detection capability. However, conventional LFIAs have low detection sensitivity. Although improvements have been made to increase the sensitivity, it is not sufficient. Here, a hamper pad, polyvinyl alcohol coated on a nitrocellulose membrane, was integrated to enhance the sensitivity of LFIA for CBZ detection. The hamper pad was inserted between the conjugated and nitrocellulose pads to delay the flow rate, thereby increasing the possibility of the antibody and target analyte binding. This platform exhibited a fourfold sensitivity increase in CBZ detection compared with the conventional LFIA, and its limit of detection was 1.6 ng/mL. In addition, a single-step operation was successfully applied to detect CBZ in rice (white rice, brown rice, sticky rice, and paddy) and soybean samples, with acceptable recoveries of 93.6%-120.0%. This novel device was compared to the standard high-performance liquid chromatography method, which shows high accuracy with a Kappa coefficient of 0.91. Therefore, improved sensitivity with a rapid, simple, and inexpensive device could facilitate the detection of CBZ residues in agricultural products for on-field screening and improved user-friendliness.


Assuntos
Benzimidazóis , Nanopartículas Metálicas , Colódio , Imunoensaio/métodos , Carbamatos , Nanopartículas Metálicas/química
4.
Heliyon ; 10(2): e24444, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38293411

RESUMO

The polysaccharides found in Caulerpa lentillifera (sea grape algae) are potentially an important bioactive resource. This study makes use of RSM (response surface methodology) to determine the optimal conditions for the extraction of valuable SGP (sea grape polysaccharides). The findings indicated that a water/raw material ratio of 10:1 mL/g, temperature of 90 °C, and extraction time of 45 min would maximize the yield, with experimentation achieving a yield of 21.576 %. After undergoing purification through DEAE-52 cellulose and Sephacryl S-100 column chromatography, three distinct fractions were obtained, namely SGP11, SGP21, and SGP31, each possessing average molecular weights of 38.24 kDa, 30.13 kDa, and 30.65 kDa, respectively. Following characterization, the fractions were shown to comprise glucose, galacturonic acid, xylose, and mannose, while the sulfate content was in the range of 12.2-21.8 %. Using Fourier transform infrared spectroscopy (FT-IR) it was possible to confirm with absolute certainty the sulfate polysaccharide attributes of SGP11, SGP21, and SGP31. NMR (nuclear magnetic resonance) findings made it clear that SGP11 exhibited α-glycosidic configurations, while the configurations of SGP21 and SGP31 were instead ß-glycosidic. The in vitro antioxidant assays which were conducted revealed that each of the fractions was able to demonstrate detectable scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cations. All fractions were also found to exhibit the capacity to scavenge NO radicals in a dose-dependent manner. SGP11, SGP21, and SGP31 were also able to display cellular antioxidant activity (CAA) against the human adenocarcinoma colon (Caco-2) cell line when oxidative damage was induced. The concentration levels were found to govern the extent of such activity. Moreover, purified SGP were found to exert strong inhibitory effects upon glycation, with the responses dependent upon dosage, thus confirming the potential for SGP to find a role as a natural resource for the production of polysaccharide-based antioxidant drugs, or products to promote improved health.

5.
PLoS One ; 18(7): e0288161, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37498897

RESUMO

Elephants are susceptible to Mycobacterium tuberculosis (M. tb) complex (MTBC) infections. Diagnosis of tuberculosis (TB) in elephants is difficult, and most approaches used for human TB diagnosis are not applicable. An interferon gamma release assay (IGRA) to diagnose TB in Asian elephants (Elephas maximus) using peripheral blood mononuclear cells (PBMCs) has been previously developed. Although the assay is shown to be valid in determining MTBC infection status, the laborious PBMC isolation process makes it difficult to use. In this study, we simplified the method by using whole blood cultures (WC) as the starting material. Using PBMC cultures for IGRA, the MTBC infection status of 15 elephants was first confirmed. Among these animals, one has been previously confirmed for M. tb infection by both TB culture and PCR and the other was confirmed for MTBC infection in this study by droplet digital PCR (ddPCR) method. WC for IGRA consisted of an unstimulated sample, a mitogen stimulated sample, and sample stimulated with recombinant M. tb antigens, ESAT6 and CFP10. Using WC for IGRA in the 15 enrolled elephants, the results showed that 7 out of 15 samples yielded MTBC infection positive status that were completely concordant with those from the results using PBMCs. To test this method, WC for IGRA were applied in another elephant cohort of 9 elephants. The results from this cohort revealed a perfect match between the results from PBMC and WC. Responses to ESAT6 or CFP10 by PBMC and WC were not completely concordant, arguing for the use of at least two M. tb antigens for stimulation. Given the ease of sample handling, smaller blood sample volumes and equivalent efficacy relative to the PBMC approach, using WC for IGRA provides a novel, rapid, and user-friendly TB diagnostic method for determining the MTBC infection in elephants.


Assuntos
Elefantes , Mycobacterium tuberculosis , Tuberculose , Animais , Humanos , Testes de Liberação de Interferon-gama/veterinária , Testes de Liberação de Interferon-gama/métodos , Leucócitos Mononucleares , Hemocultura , Tuberculose/diagnóstico , Tuberculose/veterinária
6.
Sci Rep ; 10(1): 14551, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32883961

RESUMO

Tuberculosis is highly contagious disease that can be transmitted between humans and animals. Asian elephants (Elephas maximus) in captivity live in close contact with humans in many Asian countries. In this study, we developed an interferon gamma release assay (IGRA) for elephant TB detection using antigens from the MTB complex (MTBC) and nontuberculous mycobacteria (NTM) as stimulating antigens (PPD, ESAT6, CFP10) to elicit a cell-mediated immune response (CMIR). The developed assay was applied to an elephant herd of more than 60 animals in Thailand, and the results were compared with those obtained through serological detection. IGRA has sufficient sensitivity for detecting elephant interferon gamma (eIFNγ) from specific antigen-stimulated PBMCs. Among 60 animals tested, 20 samples (33.3%) showed negative results for both MTBC and NTM infection. Eighteen samples (30%) showed positive responses against PPD from M. bovis and/or ESAT6 and CFP10, indicating MTBC infection. In contrast, only 15.6% showed seropositivity in a commercial serological test kit for elephant TB. The discrepancies between serological and CMIR highlight that the two methods may detect different stages of elephant TB. Therefore, employing both tests may enable them to complement each other in correctly identifying elephants that have been exposed to MTBC.


Assuntos
Testes de Liberação de Interferon-gama/métodos , Mycobacterium tuberculosis/patogenicidade , Tuberculose/diagnóstico , Animais , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Elefantes , Ensaio de Imunoadsorção Enzimática , Feminino , Imunidade Celular/fisiologia , Interferon gama/metabolismo , Leucócitos Mononucleares/metabolismo , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/metabolismo , Micobactérias não Tuberculosas/imunologia , Micobactérias não Tuberculosas/metabolismo , Micobactérias não Tuberculosas/patogenicidade , Tuberculose/metabolismo
7.
J Zhejiang Univ Sci B ; 15(2): 165-72, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24510709

RESUMO

A novel monoclonal antibody (MAb) against oxytetracycline (OTC) was generated and characterized. The MAb was used in the development of an enzyme-linked immunosorbant assay (ELISA)-based detection system. An OTC-bovine serum albumin (BSA) conjugate was prepared and used in the immunization of mice. A conventional somatic cell fusion technique was used to generate MAb-secreting hybridomas denoted 2-4F, 7-3G, and 11-11A. An indirect competitive ELISA (icELISA) was applied to measure the sensitivity and specificity of each MAb in terms of its 50% inhibitory concentration (IC50) and percentage of cross-reactivity, respectively. MAb 2-4F exhibited the highest sensitivity, with an IC50 of 7.01 ng/ml. This MAb showed strong cross-reactivity to rolitetracycline, but no cross-reactivity to other unrelated antibiotics. When MAb 2-4F was used to detect OTC from shrimp samples, the recoveries were in the range of 82%-118% for an intra-assay and 96%-113% for an inter-assay. The coefficients of variation of the assays were 3.9%-13.9% and 5.5%-14.9%, respectively.


Assuntos
Anticorpos Monoclonais/química , Resíduos de Drogas/análise , Oxitetraciclina/química , Penaeidae/química , Animais , Bovinos , Ensaio de Imunoadsorção Enzimática , Feminino , Concentração Inibidora 50 , Camundongos , Camundongos Endogâmicos BALB C , Oxitetraciclina/análise , Reprodutibilidade dos Testes , Rolitetraciclina/química , Sensibilidade e Especificidade , Soroalbumina Bovina
8.
Nat Prod Res ; 27(21): 1949-55, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23672215

RESUMO

A new biphenyl, named schomburgbiphenyl (1), and 14 known compounds were isolated from the wood of Garcinia schomburgkiana. The known constituents were identified as follows: three xanthones (2, 8 and 9), two benzophenones (3 and 4), three biphenyls (5-7), three biflavonoids (10-12) and three steroids. Compounds 3 and 4 were highly cytotoxic to SW620 cell line (100 times more than the positive control, doxorubicin) and were also strongly active against KATO-III, HepG2 and CHAGO cell lines. Compound 6 was specifically cytotoxic towards SW620 cells, whereas compound 8 displayed strong cytotoxicity against all five cell lines tested.


Assuntos
Garcinia/química , Madeira/química , Benzofenonas/química , Benzofenonas/farmacologia , Biflavonoides/química , Biflavonoides/farmacologia , Compostos de Bifenilo/química , Compostos de Bifenilo/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Estrutura Molecular , Extratos Vegetais/farmacologia , Esteroides/química , Esteroides/farmacologia , Xantonas/química , Xantonas/farmacologia
9.
Fitoterapia ; 85: 1-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23274776

RESUMO

Two new eudesmane-type sesquiterpenes, named foveolide A (1) and foveoeudesmenone (2), one new sesquiterpenoid dimer, foveolide B (3) and a new phenolic compound, foveospirolide (4), were isolated along with six known compounds, including 4(15)-eudesmene-1ß, 6α-diol (5), 4(15)-eudesmene-1ß, 5α-diol (6), friedelin, taraxerol, betulin and ethyl rosmarinate, from the stems of Ficus foveolata. The structures of these new compounds were characterized by spectroscopic methods (IR, MS and NMR). Compound 1 exhibited moderate cytotoxicity against SW620, HepG2, BT474 and KATO-III cancer cell lines, whereas compound 3 was specifically cytotoxic toward SW620 cell line.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Ficus/química , Sesquiterpenos de Eudesmano/isolamento & purificação , Sesquiterpenos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Estrutura Molecular , Sesquiterpenos/química , Sesquiterpenos de Eudesmano/química
10.
Fitoterapia ; 82(7): 1047-51, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21745551

RESUMO

A new 1,3-diketofriedelane triterpene, 21α-hydroxyfriedelane-1,3-dione (1) together with six known friedelane triterpenes, 30-hydroxyfriedelane-1,3-dione (2), friedelane-1,3-dione (3), 26-hydroxyfriedelane-1,3-dione (4), friedelin (5), 21α-hydroxy-D:A-friedo-olean-3-one (6) and kokoonol (7), were isolated from the stems of Salacia verrucosa (Celastraceae). The structures of these triterpenes were characterized by spectroscopic methods (IR, MS and NMR). Compound 3 was strongly cytotoxic against SW620 cell line, whereas compounds 4 and 6 were moderately active against SW620, HepG2 and KATO-III cancer cell lines.


Assuntos
Extratos Vegetais/química , Salacia/química , Triterpenos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Triterpenos/química
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