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1.
Cell ; 187(4): 861-881.e32, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38301646

RESUMO

Genomic instability can trigger cancer-intrinsic innate immune responses that promote tumor rejection. However, cancer cells often evade these responses by overexpressing immune checkpoint regulators, such as PD-L1. Here, we identify the SNF2-family DNA translocase SMARCAL1 as a factor that favors tumor immune evasion by a dual mechanism involving both the suppression of innate immune signaling and the induction of PD-L1-mediated immune checkpoint responses. Mechanistically, SMARCAL1 limits endogenous DNA damage, thereby suppressing cGAS-STING-dependent signaling during cancer cell growth. Simultaneously, it cooperates with the AP-1 family member JUN to maintain chromatin accessibility at a PD-L1 transcriptional regulatory element, thereby promoting PD-L1 expression in cancer cells. SMARCAL1 loss hinders the ability of tumor cells to induce PD-L1 in response to genomic instability, enhances anti-tumor immune responses and sensitizes tumors to immune checkpoint blockade in a mouse melanoma model. Collectively, these studies uncover SMARCAL1 as a promising target for cancer immunotherapy.


Assuntos
Antígeno B7-H1 , DNA Helicases , Imunidade Inata , Melanoma , Evasão Tumoral , Animais , Camundongos , Antígeno B7-H1/metabolismo , Instabilidade Genômica , Melanoma/imunologia , Melanoma/metabolismo , DNA Helicases/metabolismo
2.
Ann Vasc Surg ; 79: 437.e1-437.e6, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34644643

RESUMO

BACKGROUND: Bacillus Calmette-Guerin (BCG) is a live, attenuated strain of Mycobacterium bovis that is used in the treatment of non-muscle invasive bladder cancer (NMIBC). Vascular complications, including mycotic aneurysms, after BCG therapy are exceedingly rare. In this patient population, the diagnosis of mycotic aneurysms can be delayed or missed due to their non-specific clinical and radiologic presentation. Literature review reveals management of mycotic aneurysms attributable to BCG therapy is widely varied.2,5-8,12,15 CASE REPORT: We report a patient who presented with mycotic aneurysm formation secondary to BCG treatment for bladder cancer that was repaired with in-line reconstruction utilizing cryoartery and buttressed with omental flap. We suggest this as an alternative treatment to in-line prosthetic graft or extra-anatomic reconstruction.


Assuntos
Aneurisma Infectado/cirurgia , Aneurisma Aórtico/cirurgia , Artérias/transplante , Vacina BCG/efeitos adversos , Mycobacterium bovis/patogenicidade , Omento/cirurgia , Retalhos Cirúrgicos , Tuberculose/cirurgia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Enxerto Vascular , Administração Intravesical , Idoso , Aneurisma Infectado/diagnóstico , Aneurisma Infectado/microbiologia , Aneurisma Aórtico/diagnóstico , Aneurisma Aórtico/microbiologia , Vacina BCG/administração & dosagem , Criopreservação , Humanos , Masculino , Resultado do Tratamento , Tuberculose/diagnóstico , Tuberculose/microbiologia , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/patologia
3.
Appl Microbiol Biotechnol ; 102(18): 7775-7793, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30022261

RESUMO

Rosmarinic acid (RA) is a highly valued natural phenolic compound that is very commonly found in plants of the families Lamiaceae and Boraginaceae, including Coleus blumei, Heliotropium foertherianum, Rosmarinus officinalis, Perilla frutescens, and Salvia officinalis. RA is also found in other members of higher plant families and in some fern and horned liverwort species. The biosynthesis of RA is catalyzed by the enzymes phenylalanine ammonia lyase and cytochrome P450-dependent hydroxylase using the amino acids tyrosine and phenylalanine. Chemically, RA can be produced via methods involving the esterification of 3,4-dihydroxyphenyllactic acid and caffeic acid. Some of the derivatives of RA include melitric acid, salvianolic acid, lithospermic acid, and yunnaneic acid. In plants, RA is known to have growth-promoting and defensive roles. Studies have elucidated the varied pharmacological potential of RA and its derived molecules, including anticancer, antiangiogenic, anti-inflammatory, antioxidant, and antimicrobial activities. The demand for RA is therefore, very high in the pharmaceutical industry, but this demand cannot be met by plants alone because RA content in plant organs is very low. Further, many plants that synthesize RA are under threat and near extinction owing to biodiversity loss caused by unscientific harvesting, over-collection, environmental changes, and other inherent features. Moreover, the chemical synthesis of RA is complicated and expensive. Alternative approaches using biotechnological methodologies could overcome these problems. This review provides the state of the art information on the chemistry, sources, and biosynthetic pathways of RA, as well as its anticancer properties against different cancer types. Biotechnological methods are also discussed for producing RA using plant cell, tissue, and organ cultures and hairy-root cultures using flasks and bioreactors. The recent developments and applications of the functional genomics approach and heterologous production of RA in microbes are also highlighted. This chapter will be of benefit to readers aiming to design studies on RA and its applicability as an anticancer agent.


Assuntos
Antineoplásicos Fitogênicos/biossíntese , Cinamatos/metabolismo , Depsídeos/metabolismo , Neoplasias/tratamento farmacológico , Plantas/genética , Animais , Antineoplásicos Fitogênicos/farmacologia , Vias Biossintéticas , Biotecnologia , Cinamatos/farmacologia , Depsídeos/farmacologia , Genômica , Humanos , Plantas/metabolismo , Ácido Rosmarínico
4.
Molecules ; 23(7)2018 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-29976903

RESUMO

Gingerols and shogaols are compounds found in ginger (Zingiber officinale Roscoe); shogaols are found in lower concentration than gingerols but exhibit higher biological activities. This work studied the effects of different drying methods including open sun drying (OSD) solar tunnel drying (STD) and hot air drying (HAD) with various temperature on the formation of six main active compounds in ginger rhizomes, namely 6-, 8-, and 10-gingerols and 6-, 8-, and 10-shogaols, as well as essential oil content. Antioxidant and antimicrobial activity of dried ginger was also evaluated. High performance liquid chromatography (HPLC) analysis showed that after HAD with variable temperature (120, 150 and 180 °C), contents of 6-, 8-, and 10-gingerols decreased, while contents of 6-, 8-, and 10-shogaol increased. High formation of 6-, 8-, and 10-shogaol contents were observed in HAD (at 150 °C for 6 h) followed by STD and OSD, respectively. OSD exhibited high content of essential oil followed by STD and HAD method. Ginger-treated with HAD exhibited the highest DPPH (IC50 of 57.8 mg/g DW) and FRAP (493.8 µM of Fe(II)/g DM) activity, compared to STD and OSD method. HAD ginger exhibited potent antimicrobial activity with lower minimum inhibition concentration (MIC) value against bacteria strains followed by STD and OSD, respectively. Ginger extracts showed more potent antimicrobial activity against Gram positive bacteria than Gram negative bacteria strains. Result of this study confirmed that conversion of gingerols to shogaols was significantly affected by different drying temperature and time. HAD at 150 °C for 6 h, provides a method for enhancing shogaols content in ginger rhizomes with improving antioxidant and antimicrobial activities.


Assuntos
Anti-Infecciosos/análise , Antioxidantes/análise , Catecóis/análise , Dessecação/métodos , Álcoois Graxos/análise , Zingiber officinale/química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Catecóis/farmacologia , Cromatografia Líquida de Alta Pressão , Álcoois Graxos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Guaiacol/análogos & derivados , Guaiacol/análise , Guaiacol/farmacologia , Testes de Sensibilidade Microbiana , Óleos Voláteis/análise , Óleos Voláteis/farmacologia , Extratos Vegetais/química , Óleos de Plantas/análise , Óleos de Plantas/farmacologia
5.
Molecules ; 23(8)2018 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-30044450

RESUMO

Since α-mangostin in mangosteen fruits was reported to be the main compound able to provide natural antioxidants, the microwave-assisted extraction process to obtain high-quality α-mangostin from mangosteen pericarp (Garcinia mangostana L.) was optimized using a central composite design and response surface methodology. The parameters examined included extraction time, microwave power, and solvent percentage. The antioxidant and antimicrobial activity of optimized and non-optimized extracts was evaluated. Ethyl acetate as a green solvent exhibited the highest concentration of α-mangostin, followed by dichloromethane, ethanol, and water. The highest α-mangostin concentration in mangosteen pericarp of 121.01 mg/g dry matter (DM) was predicted at 3.16 min, 189.20 W, and 72.40% (v/v). The verification of experimental results under these optimized conditions showed that the α-mangostin value for the mangosteen pericarp was 120.68 mg/g DM. The predicted models were successfully developed to extract α-mangostin from the mangosteen pericarp. No significant differences were observed between the predicted and the experimental α-mangostin values, indicating that the developed models are accurate. The analysis of the extracts for secondary metabolites showed that the total phenolic content (TPC) and total flavonoid content (TFC) increased significantly in the optimized extracts (OE) compared to the non-optimized extracts (NOE). Additionally, trans-ferulic acid and catechin were abundant among the compounds identified. In addition, the optimized extract of mangosteen pericarp with its higher α-mangostin and secondary metabolite concentrations exhibited higher antioxidant activities with half maximal inhibitory concentration (IC50) values of 20.64 µg/mL compared to those of the NOE (28.50 µg/mL). The OE exhibited the highest antibacterial activity, particularly against Gram-positive bacteria. In this study, the microwave-assisted extraction process of α-mangostin from mangosteen pericarp was successfully optimized, indicating the accuracy of the models developed, which will be usable in a larger-scale extraction process.


Assuntos
Antibacterianos/química , Antioxidantes/química , Garcinia mangostana/química , Química Verde/métodos , Extratos Vegetais/química , Xantonas/química , Catequina/química , Ácidos Cumáricos/química , Flavonoides/química , Frutas/química , Humanos , Fenóis/química , Extratos Vegetais/isolamento & purificação , Metabolismo Secundário , Solventes , Xantonas/isolamento & purificação
6.
Molecules ; 23(8)2018 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-30049990

RESUMO

Recently, the quality-by-design concept has been widely implemented in the optimization of pharmaceutical processes to improve batch-to-batch consistency. As flavonoid compounds in pigmented rice bran may provide natural antioxidants, extraction of flavonoid components from red and brown rice bran was optimized using central composite design (CCD) and response surface methodology (RSM). Among the solvents tested, ethanol was most efficient for extracting flavonoids from rice bran. The examined parameters were temperature, solvent percentage, extraction time, and solvent-to-solid ratio. The highest total flavonoid content (TFC) in red rice bran was predicted as 958.14 mg quercetin equivalents (QE)/100 g dry matter (DM) at 58.5 °C, 71.5% (v/v), 36.2 min, and 7.94 mL/g, respectively, whereas the highest TFC in brown rice bran was predicted as 782.52 mg QE/100 g DM at 56.7 °C, 74.4% (v/v), 36.9 min, and 7.18 mL/g, respectively. Verification experiment results under these optimized conditions showed that the TFC values for red and brown rice bran were 962.38 and 788.21 mg QE/100 g DM, respectively. No significant differences were observed between the predicted and experimental TFC values, indicating that the developed models are accurate. Analysis of the extracts showed that apigenin and p-coumaric acid are abundant in red and brown rice bran. Further, red rice bran with its higher flavonoid content exhibited higher nitric oxide and 2,2-diphenyl-1-picrylhydrazyl scavenging activities (EC50 values of 41.3 and 33.6 µg/mL, respectively) than brown rice bran. In this study, an extraction process for flavonoid compounds from red and brown rice bran was successfully optimized. The accuracy of the developed models indicated that the approach is applicable to larger-scale extraction processes.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Oryza/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Fracionamento Químico/métodos , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Solventes , Temperatura
7.
BMC Complement Altern Med ; 16(1): 382, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27687000

RESUMO

BACKGROUND: Herbal materials should be stored at optimal conditions in order to retain their nutritional quality. Proper storage has a significant impact on the quality of the herbs and spices. METHODS: The effects of storage temperature (5 and 15 °C) and time (4 and 8 months) on the phytochemical constituents associated with the antioxidant and antibacterial activities of ginger varieties (Halia bentong and Halia bara) were evaluated to determine the optimal storage conditions for ginger rhizomes. Total flavonoid content (TFC) and Total phenolic content (TPC) were measured using the spectrophotometric method. Individual phenolic acids and flavonoids, 6-gingerol and 6-shogaol were identified by ultra-high performance liquid chromatography. Ferric reducing antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were used for evaluation of antioxidant activities. An antibacterial property of ginger varieties was evaluated using well diffusion method. RESULTS: Dry matter, TPC, TFC and individual phenolics and flavonoids content, 6-gingerol and 6-shogaol content noticeably decreased at 5 and 15 °C during the storage times from 4 to 8 months. Highest content of flavonoids, phenolic acids, 6-gingerol, and 6-shogaol was observed in fresh samples followed by rhizomes stored at 5 °C for 4 months. Storage at 15 °C for 4 months reduced the phytochemical content significantly. Cinnamic acid and tannic acid were not detected in those variety stored at 15 °C for 4 and 8 months. Polyphenol oxidase (PPO) activity was associated significantly with storage time and temperature. Highest and lowest PPO activity was observed in stored and fresh rhizomes respectively. Antioxidant and antimicrobial activities gradually declined with the increase of storage temperature (from 5 to 15 °C) and duration (from 4 to 8 months) in both the varieties. Freshly harvested Halia bara variety had higher antioxidant and antibacterial activity compared to the Halia bentong variety. CONCLUSIONS: Halia bara exhibited valuable phytochemical content and antioxidant and antibacterial activities at higher levels compared to that exhibited by Halia bentong rhizomes. In general, storage of Malaysian ginger varieties at temperature of 5 °C is recommended and the storage time should be not more than 4 months. This storage condition will provide greater stability to the concentration of the phytochemical constituents more similar to the fresh material.

8.
BMC Complement Altern Med ; 16: 104, 2016 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-27004511

RESUMO

BACKGROUND: Zingiber zerumbet (L.) is a traditional Malaysian folk remedy that contains several interesting bioactive compounds of pharmaceutical quality. METHODS: Total flavonoids and total phenolics content from the leaf, stem, and rhizome of Z. zerumbet at 3 different growth stages (3, 6, and 9 months) were determined using spectrophotometric methods and individual flavonoid and phenolic compounds were identified using ultra-high performance liquid chromatography method. Chalcone Synthase (CHS) activity was measured using a CHS assay. Antioxidant activities were evaluated by ferric reducing antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays. The antibacterial activity was determined against Gram-positive and Gram-negative bacteria using the disc diffusion method. RESULTS: Highest content of total flavonoid [29.7 mg quercetin equivalents (QE)/g dry material (DM)] and total phenolic (44.8 mg gallic acid equivalents (GAE)/g DM) were detected in the rhizome extracts of 9-month-old plants. As the plant matured from 3 to 9 months, the total flavonoid content (TFC) and total phenolic content (TPC) decreased in the leaf, but increased significantly in the rhizomes. Among the secondary metabolites identified, the most abundant, based on the concentrations, were as follows: flavonoids, catechin > quercetin > rutin > luteolin > myricetin > kaempferol; phenolic acids, gallic acid > ferulic acid > caffeic acid > cinnamic acid. Rhizome extracts from 9-month-old plants demonstrated the highest CHS activity (7.48 nkat/mg protein), followed by the 6-month-old rhizomes (5.79 nkat/mg protein) and 3-month-old leaf (4.76 nkat/mg protein). Nine-month-old rhizomes exhibited the highest DPPH activity (76.42 %), followed by the 6-month-old rhizomes (59.41 %) and 3-month-old leaves (57.82 %), with half maximal inhibitory concentration (IC50) of 55.8, 86.4, and 98.5 µg/mL, respectively, compared to that of α- tocopherol (84.19 %; 44.8 µg/mL) and butylated hydroxytoluene (BHT) (70.25 %; 58.6 µg/mL). The highest FRAP activity was observed in 9-month-old rhizomes, with IC50 of 62.4 µg/mL. Minimal Inhibitory Concentration (MIC) of Z. zerumbet extracts against Gram-positive and Gram-negative bacteria ranged from 30 to >100 µg/mL. Among the bacterial strains examined, Staphylococcus aureus was sensitive to the leaf extract of Z. zerumbet, with MIC of 30.0 µg/mL and other strains were sensitive to the rhizome extracts. CONCLUSIONS: Three- and 9-month-old plants are recommended when harvesting the leaf and rhizome of Z. zerumbet, respectively, in order to obtain effective pharmaceutical quality of the desired compounds.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Zingiberaceae/química , Aciltransferases/metabolismo , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Fenóis/análise , Zingiberaceae/crescimento & desenvolvimento
9.
BMC Complement Altern Med ; 16: 152, 2016 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-27234523

RESUMO

BACKGROUND: Sweet potato (Ipomoea batatas L.) is one of the most important consumed crops in many parts of the world because of its economic importance and content of health-promoting phytochemicals. METHODS: With the sweet potato (Ipomoea batatas L.) as our model, we investigated the exogenous effects of three plant-growth regulators methyl jasmonate (MeJA), salicylic acid (SA), and abscisic acid (ABA) on major phytochemicals in relation to phenylalanine ammonia lyase (PAL) activity. Specifically, we investigated the total phenolic content (TPC), total flavonoid content (TFC), total anthocyanin content (TAC), and total ß-carotene content (TCC). Individual phenolic and flavonoid compounds were identified using ultra-high performance liquid chromatography (UHPLC). Antioxidant activities of treated plants were evaluated using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and a ß-carotene bleaching assay. Anticancer activity of extracts was evaluated against breast cancer cell lines (MCF-7 and MDA-MB-231) using MTT assay. RESULTS: TPC, TFC, TAC, and TCC and antioxidant activities were substantially increased in MeJA-, SA-, and ABA-treated plants. Among the secondary metabolites identified in this study, MeJA application significantly induced production of quercetin, kaempferol, myricetin, gallic acid, chlorogenic acid, 3,5-dicaffeoylquinic acid, and 4,5-dicaffeoylquinic acid. Luteolin synthesis was significantly induced by SA application. Compared with control plants, MeJA-treated sweet potato exhibited the highest PAL activity, followed by SA and ABA treatment. The high DPPH activity was observed in MeJA followed by SA and ABA, with half-maximal inhibitory concentration (IC50) values of 2.40, 3.0, and 3.40 mg/mL compared with α-tocopherol (1.1 mg/mL). Additionally, MeJA-treated sweet potato showed the highest ß-carotene bleaching activity, with an IC50 value of 2.90 mg/mL, followed by SA (3.30 mg/mL), ABA (3.70 mg/mL), and control plants (4.5 mg/mL). Extracts of sweet potato root treated with MeJA exhibited potent anticancer activity with IC50 of 0.66 and 0.62 mg/mL against MDA-MB-231 and MCF-7 cell lines respectively, compared to that of extracts of sweet potato treated with SA (MDA-MB-231 = 0.78 mg/mL; MCF-7 = 0.90 mg/mL) and ABA (MDA-MB-231 = 0.94 mg/mL; MCF-7 = 1.40 mg/mL). The results of correlation analysis showed that anthocyanins and flavooids are corresponding compounds in sweet potato root extracts for anticancer activity against breast cancer cell lines. CONCLUSIONS: MeJA has great potential to enhance the production of important health-promoting phytochemicals in sweet potato.


Assuntos
Ipomoea batatas/química , Reguladores de Crescimento de Plantas/farmacologia , Ácido Abscísico/farmacologia , Acetatos/farmacologia , Antocianinas/metabolismo , Antineoplásicos Fitogênicos/metabolismo , Antioxidantes/metabolismo , Ciclopentanos/farmacologia , Flavonóis/metabolismo , Ipomoea batatas/efeitos dos fármacos , Ipomoea batatas/metabolismo , Oxilipinas/farmacologia , Fenóis/metabolismo , Ácido Salicílico/farmacologia , beta Caroteno/metabolismo
10.
Molecules ; 21(6)2016 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-27322227

RESUMO

The effects of different drying methods (freeze drying, vacuum oven drying, and shade drying) on the phytochemical constituents associated with the antioxidant activities of Z. officinale var. rubrum Theilade were evaluated to determine the optimal drying process for these rhizomes. Total flavonoid content (TFC), total phenolic content (TPC), and polyphenol oxidase (PPO) activity were measured using the spectrophotometric method. Individual phenolic acids and flavonoids, 6- and 8-gingerol and shogaol were identified by ultra-high performance liquid chromatography method. Ferric reducing antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were used for the evaluation of antioxidant activities. The highest reduction in moisture content was observed after freeze drying (82.97%), followed by vacuum oven drying (80.43%) and shade drying (72.65%). The highest TPC, TFC, and 6- and 8-shogaol contents were observed in samples dried by the vacuum oven drying method compared to other drying methods. The highest content of 6- and 8-gingerol was observed after freeze drying, followed by vacuum oven drying and shade drying methods. Fresh samples had the highest PPO activity and lowest content of flavonoid and phenolic acid compounds compared to dried samples. Rhizomes dried by the vacuum oven drying method represent the highest DPPH (52.9%) and FRAP activities (566.5 µM of Fe (II)/g DM), followed by freeze drying (48.3% and 527.1 µM of Fe (II)/g DM, respectively) and shade drying methods (37.64% and 471.8 µM of Fe (II)/g DM, respectively) with IC50 values of 27.2, 29.1, and 34.8 µg/mL, respectively. Negative and significant correlations were observed between PPO and antioxidant activity of rhizomes. Vacuum oven dried rhizomes can be utilized as an ingredient for the development of value-added food products as they contain high contents of phytochemicals with valuable antioxidant potential.


Assuntos
Antioxidantes/química , Catecol Oxidase/metabolismo , Extratos Vegetais/química , Antioxidantes/farmacologia , Catecol Oxidase/química , Catecóis/química , Álcoois Graxos/química , Flavonoides/química , Flavonoides/farmacologia , Oxirredução , Fenóis/química , Extratos Vegetais/farmacologia , Rizoma/química , Zingiberaceae/química
11.
Molecules ; 21(7)2016 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-27355939

RESUMO

Antimicrobial substances may be synthetic, semisynthetic, or of natural origin (i.e., from plants and animals). Antimicrobials are considered "miracle drugs" and can determine if an infected patient/animal recovers or dies. However, the misuse of antimicrobials has led to the development of multi-drug-resistant bacteria, which is one of the greatest challenges for healthcare practitioners and is a significant global threat. The major concern with the development of antimicrobial resistance is the spread of resistant organisms. The replacement of conventional antimicrobials by new technology to counteract antimicrobial resistance is ongoing. Nanotechnology-driven innovations provide hope for patients and practitioners in overcoming the problem of drug resistance. Nanomaterials have tremendous potential in both the medical and veterinary fields. Several nanostructures comprising metallic particles have been developed to counteract microbial pathogens. The effectiveness of nanoparticles (NPs) depends on the interaction between the microorganism and the NPs. The development of effective nanomaterials requires in-depth knowledge of the physicochemical properties of NPs and the biological aspects of microorganisms. However, the risks associated with using NPs in healthcare need to be addressed. The present review highlights the antimicrobial effects of various nanomaterials and their potential advantages, drawbacks, or side effects. In addition, this comprehensive information may be useful in the discovery of broad-spectrum antimicrobial drugs for use against multi-drug-resistant microbial pathogens in the near future.


Assuntos
Anti-Infecciosos/administração & dosagem , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Nanopartículas , Animais , Antibacterianos/administração & dosagem , Antifúngicos/administração & dosagem , Antivirais/administração & dosagem , Materiais Biocompatíveis/química , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Humanos , Nanopartículas Metálicas/química , Nanocompostos/química , Nanopartículas/química , Nanotecnologia
12.
Molecules ; 21(9)2016 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-27618000

RESUMO

Sweet basil (Ocimum basilicum Linnaeus) is aromatic herb that has been utilized in traditional medicine. To improve the phytochemical constituents and pharmaceutical quality of sweet basil leaves, ultraviolet (UV)-B irradiation at different intensities (2.30, 3.60, and 4.80 W/m²) and durations (4, 6, 8, and 10-h) was applied at the post-harvest stage. Total flavonoid content (TFC) and total phenolic content (TPC) were measured using spectrophotometric method, and individual flavonoids and phenolic acids were identified using ultra-high performance liquid chromatography. As a key enzyme for the metabolism of flavonoids, chalcone synthase (CHS) activity, was measured using a CHS assay. Antioxidant activity and antiproliferative activity of extracts against a breast cancer cell line (MCF-7) were evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays, respectively. UV-B irradiation at an intensity of 3.60 W/m² increased TFC approximately 0.85-fold and also increased quercetin (0.41-fold), catechin (0.85-fold), kaempferol (0.65-fold) rutin (0.68-fold) and luteolin (1.00-fold) content. The highest TPC and individual phenolic acid (gallic acid, cinnamic acid and ferulic acid) was observed in the 3.60 W/m² of UV-B treatment. Cinnamic acid and luteolin were not detected in the control plants, production being induced by UV-B irradiation. Production of these secondary metabolites was also significantly influenced by the duration of UV-B irradiation. Irradiation for 8-h led to higher TFC, TPC and individual flavonoids and phenolic acids than for the other durations (4, 8, and 10-h) except for cinnamic acid, which was detected at higher concentration when irradiated for 6-h. Irradiation for 10-h significantly decreased the secondary metabolite production in sweet basil leaves. CHS activity was induced by UV-B irradiation and highest activity was observed at 3.60 W/m² of UV-B irradiation. UV-B treated leaves presented the highest DPPH activity and antiproliferative activity with a half-maximal inhibitory concentration (IC50) value of 56.0 and 40.8 µg/mL, respectively, over that of the control plants (78.0 and 58.2 µg/mL, respectively). These observations suggest that post-harvest irradiation with UV-B can be considered a promising technique to improve the healthy-nutritional and pharmaceutical properties of sweet basil leaves.


Assuntos
Antioxidantes , Proliferação de Células/efeitos dos fármacos , Flavonoides , Hidroxibenzoatos , Ocimum basilicum/química , Folhas de Planta/química , Raios Ultravioleta , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Feminino , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Humanos , Hidroxibenzoatos/química , Hidroxibenzoatos/isolamento & purificação , Hidroxibenzoatos/farmacologia , Células MCF-7
13.
Curr Issues Mol Biol ; 17: 57-73, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25706446

RESUMO

Allele mining is a promising way to dissect naturally occurring allelic variants of candidate genes with essential agronomic qualities. With the identification, isolation and characterisation of blast resistance genes in rice, it is now possible to dissect the actual allelic variants of these genes within an array of rice cultivars via allele mining. Multiple alleles from the complex locus serve as a reservoir of variation to generate functional genes. The routine sequence exchange is one of the main mechanisms of R gene evolution and development. Allele mining for resistance genes can be an important method to identify additional resistance alleles and new haplotypes along with the development of allele-specific markers for use in marker-assisted selection. Allele mining can be visualised as a vital link between effective utilisation of genetic and genomic resources in genomics-driven modern plant breeding. This review studies the actual concepts and potential of mining approaches for the discovery of alleles and their utilisation for blast resistance genes in rice. The details provided here will be important to provide the rice breeder with a worthwhile introduction to allele mining and its methodology for breakthrough discovery of fresh alleles hidden in hereditary diversity, which is vital for crop improvement.


Assuntos
Alelos , Mineração de Dados/métodos , Resistência à Doença/genética , Genômica/métodos , Oryza/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Biologia Computacional/métodos , Interações Hospedeiro-Patógeno
14.
Biol Res ; 48: 9, 2015 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-25761515

RESUMO

BACKGROUND: The present study was conducted in order to evaluate the fatty acid profile, anti-oxidant and anti-bacterial activities from the microwave aqueous extract of the leaves of three different varieties of Labisia pumila Benth. RESULTS: The chemical analysis of the extract showed that fatty acids (palmitic, palmitoleic, stearic, oleic, linoleic and α-linolenic) acid as the main components in three varieties of L. pumila leaves. Furthermore, the obtained results of the anti-oxidant revealed that L. pumila var. alata contained higher anti-oxidative activities compared to var. pumila and var. lanceolata. However, these values were lower than the tested anti-oxidant standards. On the other hand, the aqueous leaf extracts in all three varieties of L. pumila were also found to inhibit a variable degree of antibacterial activities against eight bacteria (four Gram-positive and four Gram-negative bacteria). CONCLUSIONS: In this study, it was observed the leaves of three varieties of L. pumila exhibited variable patterns of fatty acids and the microwave aqueous extraction possess anti-oxidant and anti-bacterial activities.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Ácidos Graxos/análise , Micro-Ondas , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Primulaceae/química , Benzotiazóis/metabolismo , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Flavonoides/análise , Sequestradores de Radicais Livres/análise , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Concentração Inibidora 50 , Óxido Nítrico/metabolismo , Fenóis/análise , Folhas de Planta/química , Primulaceae/classificação , Ácidos Sulfônicos/metabolismo
15.
J Oral Maxillofac Surg ; 73(7): 1341-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25936782

RESUMO

PURPOSE: The Mandible Injury Severity Score (MISS) has been used to evaluate adult mandibular fractures. The purpose of this study was to evaluate the MISS in a cohort of pediatric patients. PATIENTS AND METHODS: This was a retrospective study of pediatric patients treated for mandibular fractures over a 20-year period. Patients were included if they had computed tomographic imaging available for review and had at least 1 post-treatment visit. The primary predictor variable was the MISS. Secondary predictors were demographic and injury-associated factors. The outcome was treatment-associated complications. Descriptive, bivariate, and multiple logistic regression statistics were computed. RESULTS: One hundred sixteen patients with mandibular fractures were identified; 73 (62.9%) met the inclusion criteria. The sample's mean age was 8.5 ± 4.1 years; 44% were girls. Motor vehicle collisions (60%) and falls (15.1%) were the most common mechanisms. More than 50% of patients had an extra-mandibular injury. The mean MISS was 13.5 ± 7.8. Forty-five percent of the sample underwent open reduction and internal fixation. Complications were noted in 20.5% of patients, of which malocclusion was the most common (8.2%). Increasing MISS was associated with complications (P < .001). After controlling for the effects of age, mechanism, cervical spine and skull base injuries, and treatment, patients with an MISS of at least 14 were significantly more likely to have a complication (odds ratio = 4.0; 95% confidence interval, 1.05-15.0; P = .04). CONCLUSIONS: In pediatric patients with mandibular fractures, increased severity of injury is associated with complications, even after controlling for the effects of multiple confounders, including open treatment.


Assuntos
Escala de Gravidade do Ferimento , Fraturas Mandibulares/classificação , Acidentes por Quedas , Acidentes de Trânsito , Adolescente , Fatores Etários , Vértebras Cervicais/lesões , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Fixação Interna de Fraturas/métodos , Humanos , Lactente , Recém-Nascido , Masculino , Má Oclusão/etiologia , Complicações Pós-Operatórias , Estudos Retrospectivos , Fraturas Cranianas/complicações , Fraturas da Coluna Vertebral/complicações , Transtornos da Articulação Temporomandibular/etiologia , Tomografia Computadorizada por Raios X/métodos
16.
BMC Complement Altern Med ; 15(1): 422, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26613959

RESUMO

BACKGROUND: Strobilanthes crispus is a well-known herb in Malaysia with various pharmaceutical properties. S. crispus is known to contain several biologically active chemical constituents which are responsible for its pharmaceutical quality. METHODS: Strobilanthes crispus leaves grown in three different locations in Malaysia [Kelantan (North-east), Selangor (Central), and Penang (North)], were investigated for differences in the content of secondary metabolites [total phenolics content (TPC), total flavonoids content (TFC), and total saponins content (TSC)] as well as for their antioxidant and anticancer properties. Phenolic acids and flavonoids were identified using ultra-high performance liquid chromatography (UHPLC). Ferric reducing antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were used to evaluate the antioxidant activities. The anticancer activity of extracts against HeLa cancer cell line was evaluated using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. RESULTS: Samples from the three different locations when extracted with two solvents (aqueous and ethanol extracts) yielded significantly different results for TPC, TFC, and TSC as well as for antioxidant activity. Aqueous extract of S. crispus leaves collected from Kelantan exhibited the highest values: TPC [12.62 mg gallic acid equivalents (GAE)/g dry matter (DM)], TFC (7.44 mg quercetin equivalents (QE)/g DM), TSC (44.7 mg diosgenin equivalents (DE)/g DM), DPPH (73.8 %), and FRAP (267.5 µM of Fe (II)/g) activity with a half-maximal inhibitory concentration (IC50) of 44.1 µg/mL compared to the extracts of leaves collected from the other two locations. The most important secondary metabolites identified in this study, based on concentration, were phenolics classified as followed: caffeic acid>ferulic acid>gallic acid>chlorogenic acid>trans-cinnamic acid; flavonoids: quercetin>rutin>catechin>apigenin>naringenin>kaempferol. Extracts of leaves collected from Kelantan exhibited better anticancer activity against HeLa cancer cell line with an IC50 of 182.5 µg/mL compared to the extracts of leaves from Selangor (IC50 = 266.4 µg/mL) and Penang (IC50 = 331.5 µg/mL) and to tamoxifen (IC50 = 63.4 µg/mL). S. crispus leaves with the highest content of secondary metabolites exhibited the most potent antioxidant and anticancer activity. CONCLUSIONS: Therefore, based on the potent antioxidant and anticancer activity of leaves extracts, it appears that S. crispus grown in the North-east of Malaysia (Kelantan) is a potential source of anticarcinogenic therapeutic compounds.


Assuntos
Acanthaceae , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Acanthaceae/química , Ácidos Carbocíclicos/análise , Ácidos Carbocíclicos/farmacologia , Antineoplásicos/análise , Antioxidantes/análise , Linhagem Celular/efeitos dos fármacos , Flavonoides/análise , Flavonoides/farmacologia , Células HeLa/efeitos dos fármacos , Humanos , Malásia , Compostos Fitoquímicos/análise , Extratos Vegetais/análise , Saponinas/análise , Saponinas/farmacologia
17.
BMC Complement Altern Med ; 15: 335, 2015 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-26399961

RESUMO

BACKGROUND: Etlingera elatior is a well-known herb in Malaysia with various pharmaceutical properties. METHODS: E. elatior flowers grown in three different locations of Malaysia (Kelantan, Pahang and Johor), were investigated for differences in their content of secondary metabolites (total phenolics [TPC], total flavonoids [TFC], and total tannin content [TTC]) as well as for their antioxidant, anticancer, and antibacterial properties. Phenolic acids and flavonoids were isolated and identified using ultra-high performance liquid chromatography (UHPLC). Ferric reducing antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were used to evaluate the antioxidant activities. The anticancer activity of extracts was evaluated using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. RESULTS: When extracted with various solvents (aqueous and ethanolic), samples from the different locations yielded significantly different results for TPC, TFC, and TTC as well as antioxidant activity. Aqueous extracts of E. elatior flowers collected from Kelantan exhibited the highest values: TPC (618.9 mg/100 g DM), TFC (354.2 mg/100 g DM), TTC (129.5 mg/100 g DM), DPPH (76.4 %), and FRAP (6.88 mM of Fe (II)/g) activity with a half-maximal inhibitory concentration (IC50) of 34.5 µg/mL compared with extracts of flowers collected from the other two locations. The most important phenolic compounds isolated in this study, based on concentration, were: gallic acid > caffeic acid > tannic acid > chlorogenic acid; and the most important flavonoids were: quercetin > apigenin > kaempferol > luteolin > myricetin. Extracts of flowers from Kelantan exhibited potent anticancer activity with a IC50of 173.1 and 196.2 µg/mL against the tumor cell lines MCF-7 and MDA-MB-231 respectively, compared with extracts from Pahang (IC50 = 204.5 and 246.2 µg/mL) and Johor samples (IC50 = 277.1 and 296.7 µg/mL). Extracts of E. elatior flowers also showed antibacterial activities against Staphylococcus aureus, Bacillus subtilis, Listeria monocytogenes, Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa with minimal inhibitory concentrations (MIC) ranging from 30 to >100 µg/mL. CONCLUSIONS: In general, therefore, based on the potent antioxidant and anticancer activity of flower extracts, it appears that E. elatior grown in the North-east of Malaysia (Kelantan) is a potential source of therapeutic compounds with anti-cancer activity.


Assuntos
Antibacterianos/farmacologia , Magnoliopsida/química , Extratos Vegetais/farmacologia , Animais , Antioxidantes/farmacologia , Compostos de Bifenilo , Flavonoides , Flores/química , Ácido Gálico , Humanos , Hidroxibenzoatos , Malásia , Testes de Sensibilidade Microbiana , Fenóis/farmacologia , Picratos , Quercetina/análise , Staphylococcus aureus/efeitos dos fármacos , Taninos/análise
18.
BMC Complement Altern Med ; 15: 258, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26223685

RESUMO

BACKGROUND: Analysis and extraction of plant matrices are important processes for the development, modernization, and quality control of herbal formulations. Response surface methodology is a collection of statistical and mathematical techniques that are used to optimize the range of variables in various experimental processes to reduce the number of experimental runs, cost , and time, compared to other methods. METHODS: Response surface methodology was applied for optimizing reflux extraction conditions for achieving high 6-gingerol and 6-shogaol contents, and high antioxidant activity in Zingiber officinale var. rubrum Theilade . The two-factor central composite design was employed to determine the effects of two independent variables, namely extraction temperature (X1: 50-80 °C) and time (X2: 2-4 h), on the properties of the extracts. The 6-gingerol and 6-shogaol contents were measured using ultra-performance liquid chromatography. The antioxidant activity of the rhizome extracts was determined by means of the 1,1-diphenyl-2-picrylhydrazyl assay. Anticancer activity of optimized extracts against HeLa cancer cell lines was measured using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. RESULTS: Increasing the extraction temperature and time induced significant response of the variables. The optimum extraction condition for all responses was at 76.9 °C for 3.4 h. Under the optimum condition, the corresponding predicted response values for 6-gingerol, 6-shogaol, and the antioxidant activity were 2.89 mg/g DW, 1.85 mg/g DW, and 84.3%, respectively. 6-gingerol and 6-shogaol were extracted under optimized condition to check the viability of the models. The values were 2.92 and 1.88 mg/g DW, and 84.0% for 6-gingerol, 6-shogaol, and the antioxidant activity respectively. The experimental values agreed with those predicted, thus indicating suitability of the models employed and the success of RSM in optimizing the extraction condition. With optimizing of reflux extraction anticancer activity of extracts against HeLa cancer cells enhanced about 16.8%. The half inhibition concentration (IC50) value of optimized and unoptimized extract was found at concentration of 20.9 and 38.4 µg/mL respectively. Optimized extract showed more distinct anticancer activities against HeLa cancer cells in a concentration of 40 µg/mL (P < 0.01) without toxicity to normal cells. CONCLUSIONS: The results indicated that the pharmaceutical quality of ginger could be improved significantly by optimizing of extraction process using response surface methodology.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/isolamento & purificação , Catecóis/isolamento & purificação , Fracionamento Químico/métodos , Medicamentos de Ervas Chinesas/isolamento & purificação , Álcoois Graxos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Zingiber officinale/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Catecóis/química , Catecóis/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Álcoois Graxos/química , Álcoois Graxos/farmacologia , Humanos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Rizoma/química
19.
Molecules ; 20(6): 10822-38, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26111171

RESUMO

Secondary metabolite contents (total phenolic, flavonoid, tocopherol, and tocotrienol) and antioxidant activities of Hashemi rice bran extracts obtained by ultrasound-assisted and traditional solvent (ethanol and 50:50 (v/v) ethanol-water) extraction techniques were compared. Phenolic and, flavonoid compounds were identified using ultra-high performance liquid chromatography and method validation was performed. Significant differences (p < 0.05) were observed among the different extraction techniques upon comparison of phytochemical contents and antioxidant activities. The extracts obtained using the ethanol-water (50:50 v/v) ultrasonic technique showed the highest amounts of total phenolics (288.40 mg/100 g dry material (DM)), total flavonoids (156.20 mg/100 g DM), and total tocotrienols (56.23 mg/100 g DM), and the highest antioxidant activity (84.21% 1,1-diphenyl-2-picrylhydrazyl (DPPH), 65.27% ß-carotene-linoleic bleaching and 82.20% nitric oxide scavenging activity). Secondary metabolite contents and antioxidant activities of the rice bran extracts varied depending of the extraction method used, and according to their effectiveness, these were organized in a decreasing order as follows: ethanol-water (50:50 v/v) ultrasonic, ethanol-water (50:50 v/v) maceration, ethanol ultrasonic and ethanol maceration methods. Ferulic, gallic and chlorogenic acids were the most abundant phenolic compounds in rice bran extracts. The phytochemical constituents of Hashemi rice bran and its antioxidant properties provides insights into its potential application to promote health.


Assuntos
Antioxidantes/química , Flavonoides/química , Oryza/química , Compostos Fitoquímicos/química , Etanol/química , Sequestradores de Radicais Livres/química , Oxirredução , Fenóis , Extratos Vegetais/química , Solventes/química
20.
BMC Complement Altern Med ; 14: 318, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-25169626

RESUMO

BACKGROUND: Extraction prior to component analysis is the primary step in the recovery and isolation of bioactive phytochemicals from plant materials. METHODS: Response surface methodology was applied to optimize ultrasound-assisted extraction conditions followed by ultra high performance liquid chromatography (UHPLC) to achieve high catechin, myricetin, and quercetin contents, and high antioxidant and anticancer activities in the curry leaf extracts. The antioxidant and anticancer activities of the leaf extracts were determined by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, respectively. The central composite experimental design (3-level, 3-factorial) was employed to consider the effects of ultrasonic power (80-150 W), temperature (40-80°C), and methanol dilution (40-80%) on the properties of the curry leaf extracts. RESULTS: It was found that ultrasonic power of 145.49 W at 55.9°C with 80% methanol was the most appropriate set of conditions for the extraction of catechin, myricetin, and quercetin from curry leaves with the consequent high antioxidant activity. Using the optimum extraction conditions, the extraction yields of catechin, myricetin, and quercetin were 0.482, 0.517, and 0.394 mg/g DW, respectively, and the antioxidant activity was enhanced to 83%. The optimized extract showed more distinct anticancer activity against HeLa cancer cells in a concentration of 67.2 µg/mL (P < 0.01) without toxicity to normal cells. CONCLUSIONS: The results indicated that the pharmaceutical quality of curry leaves could be improved significantly by optimizing the extraction process using response surface methodology.


Assuntos
Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Murraya/química , Folhas de Planta/química , Antineoplásicos/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Células HeLa , Humanos , Modelos Estatísticos , Extratos Vegetais/química , Projetos de Pesquisa , Sonicação
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