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1.
Environ Manage ; 73(6): 1089-1093, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38649482

RESUMO

The military-industrial complex, military operations, and wars are major contributors to exacerbating both climate change and biodiversity crises. However, their environmental impacts are often shadowed due to national security reasons. The current paper aims to go through the devastating impacts of military operations and wars on climate change and biodiversity loss and challenges that hinder the inclusion of military-related activities into environmental crisis mitigation efforts. The information blind spot induced by concerns about national security reasons jeopardizes the efforts to involve the military-industrial complex and military operations in the global climate and biodiversity agendas. Besides that, many military-related challenges, such as specificity of operational requirements and lifecycles, dependence on fossil fuels, complex supply change, inadequate civilian technologies and innovations, and requirements of structural changes, can hinder emission reduction. Meanwhile, wars and conflicts not only threaten to drain all human and material resources available to tackle environmental problems but also inflict long-lasting destructions, pains, and trauma that can lead to hatred and distrust among nations and parties. With the rising hatred and distrust, global agreement and commitment to address climate change and biodiversity will hardly be achieved. Thus, promoting peace is the humanistic and planetary conscience.


Assuntos
Biodiversidade , Mudança Climática , Conservação dos Recursos Naturais/métodos , Humanos , Guerra , Militares
2.
Molecules ; 27(3)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35163863

RESUMO

Cannabis is well-known for its numerous therapeutic activities, as demonstrated in pre-clinical and clinical studies primarily due to its bioactive compounds. The Cannabis industry is rapidly growing; therefore, product development and extraction methods have become crucial aspects of Cannabis research. The evaluation of the current extraction methods implemented in the Cannabis industry and scientific literature to produce consistent, reliable, and potent medicinal Cannabis extracts is prudent. Furthermore, these processes must be subjected to higher levels of scientific stringency, as Cannabis has been increasingly used for various ailments, and the Cannabis industry is receiving acceptance in different countries. We comprehensively analysed the current literature and drew a critical summary of the extraction methods implemented thus far to recover bioactive compounds from medicinal Cannabis. Moreover, this review outlines the major bioactive compounds in Cannabis, discusses critical factors affecting extraction yields, and proposes future considerations for the effective extraction of bioactive compounds from Cannabis. Overall, research on medicinal marijuana is limited, with most reports on the industrial hemp variety of Cannabis or pure isolates. We also propose the development of sustainable Cannabis extraction methods through the implementation of mathematical prediction models in future studies.


Assuntos
Canabinoides/isolamento & purificação , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão/métodos , Maconha Medicinal/química , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Humanos
3.
Chem Biodivers ; 18(5): e2001050, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33719150

RESUMO

Scaevola spinescens is endemic to Australia and has traditionally been used by Aboriginal and Torres Strait Islander communities to treat a variety of conditions including colds, flu, fever, stomach pain, urinary disorders, sores, tinea, leprosy, and cancer. Extracts prepared from S. spinescens are non-toxic and have been linked with various medicinal properties including antiviral, antibacterial, anti-inflammatory, and anticancer activities. These studies support the ethnopharmacological use of S. spinescens by Indigenous peoples of Australia and highlight the need for further investigations on the plant for potential use in pharmaceutical and food applications. This review provides a comprehensive, up-to-date review of the literature on S. spinescens focusing on the traditional use, medicinal properties, phytochemicals, and factors that affect their composition during pre-treatment and extraction, as well as providing a framework for future studies of the plant.


Assuntos
Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Magnoliopsida/química , Compostos Fitoquímicos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Austrália , Etnofarmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação
4.
Mol Biol Rep ; 47(2): 897-905, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31724126

RESUMO

Pancreatic cancer (PC) is one of the leading causes of cancer death in Western societies. The absence of specific symptoms, late diagnosis and the resistance towards chemotherapy result in significant treatment difficulties. As such, it is important to find more effective therapeutic agents for the treatment of PC. Helicteres hirsuta Lour. (H. hirsuta) has been traditionally used in many countries for the treatment of various ailments, indicating that it contains potential therapeutic agents. This study aimed to derive different fractions from the saponin-enriched extract of H. hirsuta stem using RP-HPLC and examine the in vitro anti-pancreatic cancer activity of the derived fractions (F0-F5). With the exception of F0, the five fractions (F1-F5) possessed strong inhibitory activity against PC cells at IC50 values of 3.11-17.12 µg/mL. The flow cytometry assays revealed the active fractions caused cell cycle arrest at S phase and promoted apoptosis in MIAPaCa-2 PC cells. The LC/MS analysis revealed that the isolated fractions contained bioactive compounds, such as caffeic acid, rosmarinic acid, sagerinic acid, usnic acid, cucurbitacins and absinthin. It can be concluded that the fractions isolated from H. hirsuta stem exhibit potent in vitro anti-pancreatic cancer activity and thus warrant further in vivo studies to assess their activity against PC followed by isolation of individual bioactive compounds and the evaluation of their anti-pancreatic cancer activity.


Assuntos
Malvaceae/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Extratos Vegetais/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Neoplasias Pancreáticas/metabolismo , Fitoterapia/métodos , Saponinas/farmacologia
5.
Mol Biol Rep ; 47(3): 2073-2084, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32065323

RESUMO

Treatment options for pancreatic cancer (PC) are severely limited due to late diagnosis, early metastasis and the inadequacy of chemotherapy and radiotherapy to combat the aggressive biology of the disease. In recent years, plant-derived bioactive compounds have emerged as a source of novel, anti-cancer agents. Used in traditional medicine worldwide, Elaeocarpus species have reported anti-inflammatory, antioxidant and anti-cancer properties. This study aimed to isolate and identify potential anti-PC compounds in the fruit of Elaeocarpus reticulatus Sm. A 50% acetone crude extract significantly decreased the viability of four pancreatic cell lines (≥ 10 µg/mL for BxPC-3 cells) and induced apoptosis in BxPC-3 and HPDE cells. Analysis by HPLC identified the triterpenoid Cucurbitacin I as a likely component of the extract. Furthermore, treatment with Cucurbitacin I significantly reduced the viability of HPDE and BxPC-3 cells, with results comparable to the same concentration of gemcitabine. Interestingly, attempts to isolate bioactive compounds revealed that the crude extract was more effective at reducing PC-cell viability than the fractionated extracts. This study provides initial insight into the bioactive constituents of E. reticulatus fruits.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Elaeocarpaceae/química , Frutas/química , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Humanos , Neoplasias Pancreáticas , Extratos Vegetais/química , Triterpenos/química , Triterpenos/farmacologia
6.
J Food Sci Technol ; 57(6): 2089-2098, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32431335

RESUMO

Banana peel, a by-product rich in phenolics and other bioactive compounds, has great potentials as a natural preservative or healthy food ingredient. However, the instability of bioactive compounds derived from banana peel limits their applications, and as such encapsulation is necessary to improve their stability and widen their applications. This study investigated the impact of spray drying conditions and coating materials on the physical, phytochemical, and antioxidant properties of the peel extract to identify the most suitable encapsulation process. The results showed that inlet temperature (ranging from 140 to 180 °C) and feeding rate (3-15 mL/min) did not significantly affect the total phenolic content (TPC) and antioxidant capacity but influenced the moisture content and recovery yield of the powder. The ratio of dry matter in fresh extract-to-coating material (DM-to-CM) (1:1-1:7 (w/w)) did not affect the moisture content. However, it affected the TPC, antioxidant properties, and recovery yield of the powder. Finally, the type of coating materials did not significantly affect TPC and antioxidant properties, but other physical properties, dopamine levels and recovery yield. The most suitable encapsulation conditions were identified as an inlet drying temperature of 150 °C, a feeding rate of 9 mL/min, a ratio of DM-to-CM of 1:1 (w/w), and coating with a combination of maltodextrin M100 and gum acacia. Powder prepared under the most suitable conditions had a spherical shape with a rough surface and had stable TPC under storage conditions of 40 °C for 4 weeks. It also has ideal physical, phytochemical and antioxidant properties and is suitable for further applications.

7.
Mol Biol Rep ; 46(3): 3265-3273, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30945069

RESUMO

Catharanthus roseus (L.) G. Don (C. roseus) is a well-known medicinal plant for its source of alkaloids solely found in the leaves. Other parts including the root are usually discarded after the alkaloid extraction. This study sought to investigate phytochemical profiles, antioxidant, antimicrobial and cytotoxic properties of the C. roseus root extract (RE) and its two sub-fractions including saponin-enriched (SE) and aqueous (AQ) fractions. The results showed that the RE was a rich source of saponins (1744.44 mg ESE/g) and phenolics (51.27 mg GAE/g), which comprised of gallic acid (25.74 mg/g), apigenin (1.45 mg/g) and kaempferol (1.58 mg/g). The SE fraction was enriched with 31% of saponins and 63% of phenolics higher than those of the RE; whereas the concentrations of saponins and phenolics of the AQ fraction were lower than those of the RE by 40% and 74%, respectively. The content of gallic acid in the SE fraction was 1.4-fold and 1.5-fold higher than those of the RE or AQ fraction, respectively. The SE fraction demonstrated potent antioxidant capacity, which was significantly higher than the RE or AQ fraction, and also exhibited strong anti-proliferative activity against 11 cancer cell lines including A2780 (ovarian), H460 (lung), A431 (skin), MIA PaCa-2 (pancreas), Du145 (prostate), HT29 (colon), MCF-7 (breast), BE2-C (neuroblastoma), SJ-G2, U87 and SMA (glioblastoma) with low GI50 values (≤ 2.00 µg/mL). The SE fraction was also shown to effectively inhibit the growth of both bacteria (Escherichia coli, Enterobacter aerogenes and Staphylococccus lugdunensis) and fungi (Candida albicans and Aspergillus niger). These findings warrant further investigation to isolate major compounds from the SE fraction and further test their antioxidant, anticancer and antimicrobial activities.


Assuntos
Catharanthus/química , Catharanthus/metabolismo , Extratos Vegetais/farmacologia , Alcaloides/farmacologia , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/metabolismo , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Flavonoides/farmacologia , Humanos , Fenóis , Compostos Fitoquímicos/metabolismo , Extratos Vegetais/metabolismo , Raízes de Plantas/metabolismo , Plantas Medicinais/metabolismo , Saponinas
8.
Harm Reduct J ; 16(1): 11, 2019 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-30732621

RESUMO

BACKGROUND: Residents in border areas are vulnerable to HIV/AIDS due to high rates of risk behaviors such as unprotected sexual practices or illicit drug use. Improving knowledge and attitude toward HIV/AIDS prevention and treatment are vital to diminish the burden of the HIV epidemic in this setting. However, evidence about this issue in Vietnam has been limited. This study aims to explore the knowledge and attitude toward HIV/AIDS among people in Vietnam border zones. METHODS: We conducted a cross-sectional study in three border communes in Thanh Hoa province with 600 HIV(-) residents. Data about socio-demographic characteristics, general HIV knowledge, knowledge about prevention of mother-to-child transmission, treatment and care, HIV testing services, and attitude toward HIV/AIDS were collected. Multivariate Tobit regression was used to determine related factors with the knowledge and attitude. RESULTS: The highest percentage of people having correct statements was for "HIV could be transmitted from mother to child" (98.2%), while the lowest percentage was for item "Know health facilities where HIV-positive people could register for care and check-up" (28.2%). People had the highest score in "Knowledge about HIV transmission routes" and the lowest score in "Knowledge about HIV/AIDS prevention measures". Most of the people were not afraid of being exposed to HIV-positive individuals (66.0%), willing to buy goods from HIV-positive sellers (78.9%), and willing to take care of people living with HIV in their family (90.1%). Education, ethnic, marital status, occupations, and HIV/AIDS information sources were found to be associated with knowledge and attitude toward HIV/AIDS. CONCLUSIONS: The general knowledge and attitude on HIV/AIDS of residents were relatively good. Educational campaigns to improve knowledge and attitude toward PLWH, involving peer educators and local associations, are potential strategies for sustaining HIV intervention in this remote setting.


Assuntos
Síndrome da Imunodeficiência Adquirida/psicologia , Infecções por HIV/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Transmissão Vertical de Doenças Infecciosas , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Síndrome da Imunodeficiência Adquirida/transmissão , Adulto , Estudos Transversais , Feminino , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Educação em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Assunção de Riscos , Fatores Socioeconômicos , Inquéritos e Questionários , Vietnã , Adulto Jovem
9.
J Food Sci Technol ; 56(3): 1360-1370, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30956315

RESUMO

Banana peel is rich in phenolic compounds and is generally considered as waste. This study aimed to maximise recovery of phenolics from banana peel using water via microwave assisted extraction. The impact of various parameters including pH of solvent, sample to solvent ratio, irradiation time with/without cooling periods, and irradiation power were investigated individually. Following this, extraction conditions were further optimised using Response Surface Methodology. The results revealed that the extraction efficiency can be significantly improved by reducing the pH of water, increasing microwave power and time. However, cooling time during irradiation did not affect the extraction efficiency. Optimal conditions were identified at pH of 1, ratio of 2:100 g/mL, 6 min irradiation, and microwave power of 960 W. Under these optimal conditions, approximately 50.55 mg phenolics could be recovered from 1 g dried peel. These conditions are recommended for recovery of phenolic compounds from banana peel for further utilisation.

10.
J Food Sci Technol ; 56(3): 1438-1444, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30956323

RESUMO

UV-C (180-280 nm) has been shown to extend the postharvest shelf-life of many horticulture crops. In this study, Tahitian limes (Citrus latifolia) were exposed to 0, 3.4, 7.2 and 10.5 kJ m-2 UV-C then stored for 28 days in air at 10 °C and 80% RH. Weight loss, peel colour, calyx abscission, ethylene production, respiration rate, total soluble solids (TSS), titratable acidity (TA) and acceptability index were assessed. The results showed that UV-C treatment maintained lime peel green colour and retained calyx attachment after 28 days storage. UV-C treatment also affected endogenous ethylene production and respiration rate, where the highest UV-C treatment (10.5 kJ m-2) maintained low ethylene production and low respiration rates after 28 days storage with no differences between the different UV-C intensities. In terms of fruit acceptability, limes were exposed to 10.5 kJ m-2 UV-C had a 60% acceptability index after 28 days storage, while untreated control fruit retained acceptability of 39%. In general, the pre-storage UV-C treatments did not affect fruit weight loss, TSS or TA contents during storage.

11.
Mol Biol Rep ; 45(6): 2125-2133, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30209740

RESUMO

Helicteres hirsuta Lour. (H. hirsuta) has been considered as a herbal medicine for the treatment of malaria and diabetes but limited studies have been conducted on its anticancer and antibacterial properties. In this study, the in vitro antibacterial and anticancer properties of the leaf and stem extracts and their two sub-fractions (aqueous and saponin-enriched butanol fractions) prepared from H. hirsuta were elucidated. MTT and CCK-8 assays were employed to assess their in vitro anticancer properties against various cancer cell lines. The antibacterial activity was assessed using the disc diffusion method and minimum inhibitory concentration (MIC) values were determined. The results revealed that the saponin-enriched fractions from H. hirsuta leaves and stems showed the highest antibacterial activity against E. coli (MIC values of 2.50 and 5.00 mg/mL, respectively) and S. lugdunensis (MIC values of 0.35 and 0.50 mg/mL, respectively). Importantly, these saponin-enriched fractions possessed strong anticancer activity in vitro towards a range of cancer cell lines including MIA PaCa-2 (pancreas); A2780 (ovarian); H460 (lung); A431 (skin); Du145 (prostate); HT29 (colon); MCF-7 (breast); SJ-G2, U87, SMA (glioblastoma) and BE2-C (neuroblastoma) at low doses (GI50 values of 0.36-11.17 µg/mL). They especially revealed potent anti-pancreatic cancer activity in vitro against MIA PaCa-2, BxPC-3 and CFPAC-1 cells with IC50 values of 1.80-6.43 µg/mL. This finding provides scientific evidence of the cytotoxic activity of the extracts prepared from H. hirsuta leaves and stems, and suggests further studies to isolate active compounds for development of new anticancer agents from these plant extracts.


Assuntos
Linhagem Celular Tumoral/efeitos dos fármacos , Malvaceae/química , Malvaceae/metabolismo , Extratos Vegetais/uso terapêutico , Antibacterianos , Anticarcinógenos , Antioxidantes , Escherichia coli/efeitos dos fármacos , Humanos , Malvaceae/genética , Testes de Sensibilidade Microbiana , Fitoterapia/métodos , Folhas de Planta , Caules de Planta , Plantas Medicinais/química , Staphylococcus lugdunensis/efeitos dos fármacos
12.
J Food Sci Technol ; 55(7): 2467-2475, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30042562

RESUMO

The green Tahitian limes (Citrus latifolia) were exposed to 7.2 kJ m-2 UV-C and 0.5 µL L-1 1-methylcyclopropene (1-MCP) treatments both separately and in combination. After treatment, fruit were stored in ethylene free (i.e. air containing < 0.005 µL L-1) or 0.1 µL L-1 ethylene at 20 °C and 100% RH. The results showed that UV-C treatment delayed skin degreening and reduced endogenous ethylene production compared to untreated control fruit, however these effects reduced over the storage time. As expected, 1-MCP inhibited ethylene production, reduced calyx abscission and retained peel greenness during the storage. Both of the combination treatments, 1-MCP + UV-C and UV-C + 1-MCP reduced endogenous ethylene production and delayed skin yellowing. In all treatments, UV-C and 1-MCP resulted in lower fruit respiration rates than untreated control fruit, however this effect diminished during 7 and 14 days storage for fruits stored in air and 0.1 µL L-1 ethylene atmosphere, respectively. There was no difference in weight loss, SSC, TA and SSC/TA ratio between the treatments and storage conditions. The results suggest that a pre-storage UV-C treatment, followed by storage at low level of ethylene improves the quality of limes, with the additional improvement when combined with 1-MCP treatment prior or after UV-C irradiation.

13.
Chem Biodivers ; 14(3)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27935659

RESUMO

While the pharmacological and toxicological properties of eucalypts are well known in indigenous Australian medicinal practice, investigations of the bioactivity of eucalypt extracts against high mortality diseases such as pancreatic cancer in Western medicine have to date been limited, particularly amongst the genera Corymbia and Angophora. Four Angophora and Corymbia species were evaluated for their phytochemical profile and efficacy against both primary and secondary pancreatic cancer cell lines. The aqueous leaf extract of Angophora hispida exhibited statistically higher total phenolic content (107.85 ± 1.46 mg of gallic acid equiv. per g) and total flavonoid content (57.96 ± 1.93 mg rutin equiv. per g) and antioxidant capacity compared to the other tested eucalypts (P < 0.05). Both A. hispida and A. floribunda aqueous extracts showed statistically similar saponin contents. Angophora floribunda extract exerted significantly greater cell growth inhibition of 77.91 ± 4.93% followed by A. hispida with 62.04 ± 7.47% (P < 0.05) at 100 µg/ml in MIA PaCa-2 cells with IC50 values of 75.58 and 87.28 µg/ml, respectively. More studies are required to isolate and identify the bioactive compounds from these two Angophora species and to determine their mode of action against pancreatic malignancies.


Assuntos
Myrtaceae/química , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/química , Austrália , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Myrtaceae/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Saponinas/análise
14.
J Food Sci Technol ; 54(8): 2270-2278, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28740283

RESUMO

The aim of this study was to develop an optimal formulation for preparation of edible films from chitosan, pea starch and glycerol using response surface methodology. Three independent variables were assigned comprising chitosan (1-2%), pea starch (0.5-1.5%) and glycerol (0.5-1%) to design an empirical model best fit in physical, mechanical and barrier attributes. Impacts of independent variables on thickness, moisture content, solubility, tensile strength, elastic modulus, elongation at break and water vapor permeability of films were evaluated. All the parameters were found to have significant effects on physical and mechanical properties of film. The optimal formulation for preparation of edible film from chitosan, pea starch and glycerol was 1% chitosan, 1.5% pea starch and 0.5% glycerol. Edible films with good physical and mechanical properties can be prepared with this formulation and thus this formulation can be further applied for testing on coating for fruit and vegetables.

15.
Biochim Biophys Acta ; 1854(12): 1842-1852, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26275807

RESUMO

Acetylene (HCCH) has a long history as a mechanism-based enzyme inhibitor and is considered an active-site probe of the particulate methane monooxygenase (pMMO). Here, we report how HCCH inactivates pMMO in Methylococcus capsulatus (Bath) by using high-resolution mass spectrometry and computational simulation. High-resolution MALDI-TOF MS of intact pMMO complexes has allowed us to confirm that the enzyme oxidizes HCCH to the ketene (C2H2O) intermediate, which then forms an acetylation adduct with the transmembrane PmoC subunit. LC-MS/MS analysis of the peptides derived from in-gel proteolytic digestion of the protein subunit identifies K196 of PmoC as the site of acetylation. No evidence is obtained for chemical modification of the PmoA or PmoB subunit. The inactivation of pMMO by a single adduct in the transmembrane PmoC domain is intriguing given the complexity of the structural fold of this large membrane-protein complex as well as the complicated roles played by the various metal cofactors in the enzyme catalysis. Computational studies suggest that the entry of hydrophobic substrates to, and migration of products from, the catalytic site of pMMO are controlled tightly within the transmembrane domain. Support of these conclusions is provided by parallel experiments with two related alkynes: propyne (CH3CCH) and trifluoropropyne (CF3CCH). Finally, we discuss the implication of these findings to the location of the catalytic site in pMMO.


Assuntos
Acetileno/metabolismo , Methylococcus capsulatus/metabolismo , Oxigenases/metabolismo , Cromatografia Líquida , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem
16.
J Chem Inf Model ; 55(12): 2731-8, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26595261

RESUMO

In this paper we present a new method for finding the optimal path for pulling a ligand from the binding pocket using steered molecular dynamics (SMD). Scoring function is defined as the steric hindrance caused by a receptor to ligand movement. Then the optimal path corresponds to the minimum of this scoring function. We call the new method MSH (Minimal Steric Hindrance). Contrary to existing navigation methods, our approach takes into account the geometry of the ligand while other methods including CAVER only consider the ligand as a sphere with a given radius. Using three different target + receptor sets, we have shown that the rupture force Fmax and nonequilibrium work Wpull obtained based on the MSH method show a much higher correlation with experimental data on binding free energies compared to CAVER. Furthermore, Wpull was found to be a better indicator for binding affinity than Fmax. Thus, the new MSH method is a reliable tool for obtaining the best direction for ligand exiting from the binding site. Its combination with the standard SMD technique can provide reasonable results for ranking binding affinities using Wpull as a scoring function.


Assuntos
Técnicas de Química Analítica/métodos , Simulação de Dinâmica Molecular , Trombina/química , Sítios de Ligação , Humanos , Ligantes , Ligação Proteica , Termodinâmica
17.
Chem Biodivers ; 12(6): 907-24, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26080737

RESUMO

The genus Eucalyptus (Myrtaceae) is mainly native to Australia; however, some species are now distributed globally. Eucalyptus has been used in indigenous Australian medicines for the treatment of a range of aliments including colds, flu, fever, muscular aches, sores, internal pains, and inflammation. Eucalyptus oils containing volatile compounds have been widely used in the pharmaceutical and cosmetics industries for a multitude of purposes. In addition, Eucalyptus extracts containing nonvolatile compounds are also an important source of key bioactive compounds, and several studies have linked Eucalyptus extracts with anticancer properties. With the increasing research interest in Eucalyptus and its health properties, this review briefly outlines the botanical features of Eucalyptus, discusses its traditional use as medicine, and comprehensively reviews its phytochemical and anticancer properties and, finally, proposes trends for future studies.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Eucalyptus/química , Compostos Fitoquímicos/química , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Humanos , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
18.
Molecules ; 20(7): 12992-3004, 2015 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-26193251

RESUMO

Olea europaea L. leaves are an agricultural waste product with a high concentration of phenolic compounds; especially oleuropein. Oleuropein has been shown to exhibit anti-proliferative activity against a number of cancer types. However, they have not been tested against pancreatic cancer, the fifth leading cause of cancer related death in Western countries. Therefore, water, 50% ethanol and 50% methanol extracts of Corregiola and Frantoio variety Olea europaea L. leaves were investigated for their total phenolic compounds, total flavonoids and oleuropein content, antioxidant capacity and anti-proliferative activity against MiaPaCa-2 pancreatic cancer cells. The extracts only had slight differences in their phytochemical properties, and at 100 and 200 µg/mL, all decreased the viability of the pancreatic cancer cells relative to controls. At 50 µg/mL, the water extract from the Corregiola leaves exhibited the highest anti-proliferative activity with the effect possibly due to early eluting HPLC peaks. For this reason, olive leaf extracts warrant further investigation into their potential anti-pancreatic cancer benefits.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Olea/química , Neoplasias Pancreáticas/tratamento farmacológico , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antineoplásicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Humanos , Glucosídeos Iridoides , Iridoides/química , Neoplasias Pancreáticas/patologia , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química
19.
Crit Rev Food Sci Nutr ; 54(4): 523-36, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24237002

RESUMO

Tea has been widely consumed around the world for thousands of years and drinking tea is a daily habit for people of all ages. Tea is a major source of flavonoids, which have become well known as antioxidants. Tea also contains caffeine and theanine, which have been found to associate with health benefits. Many animal and epidemiological studies have been conducted to investigate the link between tea consumption and human health. However, common questions that arise about tea consumption include: whether all teas are the same, why drinking tea is linked with health benefits, how do the different ways of tea preparation impact on availability of tea components, how much and how long a person should consume tea to obtain health benefits, and whether there is any negative health effect associated with drinking tea. To answer these questions, this paper outlines the tea components and their link to human health, discusses major factors affecting availability of tea components in a tea cup, and reviews the latest epidemiological evidence linking tea consumption to human health.


Assuntos
Chá/química , Catequina , Flavonoides , Humanos , Estrutura Molecular
20.
Data Brief ; 54: 110342, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38586136

RESUMO

Environmental activism is crucial for raising public awareness and support toward addressing the climate crisis. However, using climate change mitigation as the cause for blockade, vandalism, and harassment activities might be counterproductive and risk causing negative repercussions and declining public support. The paper describes a dataset of metadata of 89 blockade, vandalism, and harassment events happening 13 countries in recent years. The dataset comprises three main categories: 1) Events, 2) Activists, and 3) Consequences. For researchers interested in environmental activism, climate change, and sustainability, the dataset is helpful in studying the effectiveness and appropriateness of strategies to raise public awareness and support. For researchers in the field of security studies and green criminology, the dataset offers resources to study features and impacts of blockade, vandalism, and harassment events. The Bayesian Mindsponge Framework (BMF) analytics was employed to validate the dataset. Consequently, the estimated result aligns with the Mindsponge Theory's theoretical reasoning.

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