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1.
Toxics ; 12(2)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38393229

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are organic compounds found in many foods and drinks, and there have been some concerns over these compounds due to their carcinogenic nature. This study evaluated the concentrations of PAH4 (BaP, BaA, BbF, and CHR) in different black tea infusions and drinks based on the origin of the tea. The release of PAH4 from tea leaves to tea infusions was significantly low, with the highest transfer being 25.81%. The mean concentrations of BaP and PAH4 in tea infusions were used to conduct a risk assessment for the Taiwanese population, which showed that the 19-65 age group had the highest estimated intake of PAH4 and BaP among all age groups. These results, however, also showed margin of exposure (MOE) values well above the benchmark of 10,000. This indicated that PAH exposure from black tea consumption for the Taiwanese population constitutes a low-level health concern.

2.
Toxics ; 12(2)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38393243

RESUMO

Tea is an integral part of Taiwanese culture and is a popular drink as it contains many beneficial compounds. However, during the processing of tea, polycyclic aromatic hydrocarbons (PAHs) may form. This study investigated the concentrations of PAH4 in different black tea leaves and tea infusions based on the origin of the tea. The samples were extracted using QuEChERS, while the content of PAH4 was analyzed by high performance liquid chromatography coupled to a fluorescence detector (HPLC-FLD). The content of PAH4 in the tea leaves ranged from 2.88 µg/kg to 218.2 µg/kg (dry weight), with the highest concentration being found in teas from Vietnam. The concentration of BaP ranged from ND to 47.92 µg/kg. The release of PAH4 from tea leaves to tea infusions was significantly low, with the highest transfer being 25.8%. In this study, all PAH4 compounds in commercial black tea leaves can be detected by QuEChERS extraction with a simple HPLC method.

3.
Artigo em Inglês | MEDLINE | ID: mdl-37314990

RESUMO

Reliable biotransfer factor (BTF) data are critical for animal-feed studies in human risk assessment. A wide range of BTF values have been reported (0.0015-0.83 d/kg), expressed as the ratio of total arsenic (tAs) concentration (µg/kg) in chicken to daily intake rate (µg/d) of tAs in feed (tAs/tAs). Data on inorganic As (iAs) for chicken meat and tAs concentrations for feed were obtained from our related study. Using the linear regression technique developed in this study, we estimated the BTF as 0.016 d/kg, as iAs/tAs (R2 > 0.7702) and 0.55 d/kg as tAs/tAs (R2 = 0.9743) for whole chicken meat. From a mass-balance perspective, we suggest that tAs be used as the denominator for the BTF unit. To illustrate our feed-risk assessment method, we analyzed commercial feeds for tAs concentration (n = 79). Consumption data for the general population (n = 2479) were obtained from a Taiwanese total diet study. Bivariate Monte Carlo simulations (n = 10,000) showed that the 95th percentile (P95) of estimated daily intake (EDI) was 0.002 µg/kg body weight (bw)/d as iAs (< the benchmark dose lower limit of 3.0 µg/kg bw/d). Our results thus show that the commercial chicken feeds assessed in this study are of low health concern for the general Taiwanese population. We discuss the factors that may have affected the assessment, such as the type of animals investigated, type of feeds, feed tested, type of chemical species used for BTF estimation and statistical approach.


Assuntos
Arsênio , Animais , Humanos , Arsênio/análise , Galinhas , Contaminação de Alimentos/análise , Medição de Risco , Ração Animal
4.
Foods ; 12(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36981057

RESUMO

Hyperglycemia has deleterious effects on pancreatic ß-cells, causing dysfunction and insulin resistance that lead to diabetes mellitus (DM). The possible causes of injury can be caused by glucose- or fructose-induced oxidative and endoplasmic reticulum (ER) stress. Hawthorn (Crataegus pinnatifida) fruit has been widely used as a hypolipidemic agent in traditional herbal medicine. The study aimed to investigate whether high fructose-induced pancreatic ß-cell dysfunction could be reversed through amelioration of ER stress by the treatment of polyphenol-enriched extract (PEHE) from hawthorn fruit. The extract was partitioned using ethyl acetate as a solvent from crude water extract (WE) of hawthorn fruits, followed by column fractionation. The results showed that the contents of total polyphenols, flavonoids and triterpenoids in PEHE could be enhanced by 2.2-, 7.7- and 1.1-fold, respectively, in comparison to the original obtained WE from hawthorn fruit. In ER stress studies, a sharp increase in the inhibitory activity on the gene expression levels of GRP79, ATF6, IRE1α and CHOP involved in ER stress was evident when dosages of PEHE at 50-100 µg/mL were used against high-fructose (150 mM)-treated cells. HPLC-MS/MS analysis showed that polyphenols and flavonoids collectively accounted for 87.03% of the total content of PEHE.

5.
Foods ; 11(4)2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35205976

RESUMO

Although the safety of commercial genetically modified (GM) soybeans has been well evaluated and GM soybeans are legally sold under government management, some consumers still have concerns about their safety. The objective of this study was to evaluate the safety of commercial GM soybeans sold in markets as a food source. In the present study, two commercial GM (GM-1 and -2) soybeans and one non-GM soybean were randomly purchased and subjected to a whole food toxicity assessment. Rats (SD), male and female, were divided into six groups (10/sex/group). Two dosages of 1 g/kg/day and 5 g/kg/day of soybeans were selected for the low- and high-dose groups. Rats were administered the soybeans via daily oral fed for 90 days. The results indicate that the body weight, organ weight, biochemistry, hematology, and urology showed no biologically adverse effects. At necropsy, no significant differences between organ weights were noted between the non-GM- and GM soybeans-treated groups. Moreover, no gross or histopathological lesions were observed in the high-dosage (5 g/kg/day) fed groups of the non-GM and GM soybean fed rats. In conclusion, this food safety assessment revealed that commercial GM soybeans are substantially equivalent to non-GM soybeans in rats.

6.
Food Funct ; 12(1): 119-132, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33242056

RESUMO

The aim of the study was to evaluate the effects of Hsian-tsao (Mesona procumbens Hemsl.) and its polysaccharides on impaired wound healing in diabetes. The results indicate that ethanol extracts of Hsian-tsao (EE) and crude polysaccharides from water extracts of Hsian-tsao (WEP) had strong inhibitory effects on methylglyoxal (MG)-induced glycation and reactive oxygen species (ROS) production. EE and WEP also decreased MG-induced inflammation-related factors in RAW 264.7 macrophages and restored MG-impaired wound-healing factors in 3T3-L1 fibroblasts. Furthermore, EE and WEP were found to dose-dependently enhance the MG-impaired phagocytosis of Staphylococcus aureus and Pseudomonas aeruginosa by macrophages. Excitingly, EE and WEP significantly enhanced wound healing on the dorsal skin through regulation of macrophage inflammatory protein-2 (MIP-2), metalloproteinase-9 (MMP-9), and tissue inhibitor of metalloproteinase-1 (TIMP-1) protein expressions in diabetic mice, as evidenced by the percentage reduction in wound surface area and the results of histopathologic scoring analysis. In conclusion, these results suggest that Hsian-tsao extract and its polysaccharides might be utilized in alternative natural therapy to promote wound healing in diabetic individuals.


Assuntos
Diabetes Mellitus Experimental/complicações , Medicamentos de Ervas Chinesas/farmacologia , Lamiaceae , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL
7.
Chemosphere ; 262: 128249, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182142

RESUMO

Saltwater fish is rich in health-promoting polyunsaturated fatty acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Excessive fish intake may also cause health hazards due to methylmercury (MeHg). A novel dose estimation method was proposed in this study to improve the quality of food matching by considering the usage ratio of cooking and processing methods in sampling design. In total, 39 table-ready samples were specified according to 2-3 common cooking methods, and MeHg and total mercury (THg) were analyzed. The results showed that mercury was detected in 20 samples (LOD = 0.01 µg/g). High MeHg samples included fried-Spanish mackerel (1.23 µg/g), non-cooked shredded swordfish (0.325 µg/g), pan-fried Spanish mackerel (0.248 µg/g), and non-cooked shredded salmon (0.208 µg/g). Consumption data (n = 166,911) were obtained from 24-h recalls in the 2005-2008 Nutrition and Health Surveys in Taiwan (NAHSIT). The average whole-group estimated daily intake (EDI_WG) was 0.018 (7.9% tolerable daily intake, TDI) for women of child-bearing age and 0.031 µg/day per kg body weight (13.6% TDI) for children. However, 95th percentile values (P95) of 90.4% TDI and 185% TDI were estimated for the two consumer-only populations, which have raised public health concerns. The ratio of % TDI to % daily reference intake (% DRI) was used as a risk-benefit (R/B) indicator. The top 4 R/B foods were: tuna sashimi (0.089 and 0.14), non-cooked shredded swordfish (0.033 and 0.052), fried-Spanish mackerel (0.027 and 0.043) and deep-fried fish balls (0.022 and 0.035) in the two perspective populations.


Assuntos
Exposição Dietética/análise , Ácidos Graxos Insaturados/análise , Peixes/metabolismo , Compostos de Metilmercúrio/análise , Alimentos Marinhos/análise , Adulto , Animais , Criança , Culinária , Ácidos Docosa-Hexaenoicos/análise , Ácido Eicosapentaenoico/análogos & derivados , Ácido Eicosapentaenoico/análise , Feminino , Humanos , Pessoa de Meia-Idade , Saúde Pública , Medição de Risco , Taiwan
8.
Antioxidants (Basel) ; 9(1)2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31936300

RESUMO

Altering the microbiota by the daily diet is highly associated with improved human health. Studies confirms the gastrointestinal protective and anti-inflammatory effects of camellia oil; however, the benefits in gut microbiota remain unclear. Camellia oils of Camellia oleifera (PCO) and C. brevistyla (TCCO) were used to evaluate probiotic growth in vitro. In addition, the protective effects of camellia oils in the acetic acid (AA)-induced colitis rat model were investigated. In vitro fermentation study showed the proliferation of Lactobacillus spp. and Bifidobacterium spp. from human intestinal microbiota was increased after TCCO treatment. Moreover, the rats pretreated with TCCO exhibited significantly less AA-induced colonic injury and hemorrhage, higher serum immunoglobulin G 1 (IgG 1) levels, lower malondialdehyde levels, and lower inflammatory cytokine production in the colon tissue compared with those in the PCO group. Surprising, the protective effect against acetic acid-induced colitis by TCCO was similar to sulfasalazine (positive control) treatment. Moreover, TCCO increased the richness and diversity of probiotics in gut microbiota. TCCO alleviated AA-induced colitis by modulating gut microbiota, reducing oxidative stress and suppressing inflammatory responses.

9.
J Food Drug Anal ; 28(3): 375-398, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35696094

RESUMO

High-fat food intake is the main source of dioxin-like compounds for humans, such as consumption of meat, dairy and eggs, and seafood products. Fruits, vegetables, and cereals have relatively low levels of dioxin-like compounds, but because of high consumption they also contribute to the food-borne intake. It is necessary to clarify dietary dioxin exposure affected by different food contamination levels and dietary habits among different geographic areas. We aimed to evaluate chronic dietary PCDD/Fs and DL-PCBs exposure in 725 individual foods in 14 categories in 6 Taiwan air quality regions (AQRs) and a total of 2441 foods from 2004 to 2018. We estimated daily PCDD/Fs + DL-PCBs intake on the basis of sex- and age-specific foodstuff ingestion rate and PCDD/Fs+ DL-PCBs concentrations using a probabilistic approach. PCDD/F+ DL-PCB levels among the different sampling periods exhibited a decreasing trend in fish and aquatic products (from 0.384 ± 0.764 to 0.206±0.223pgWHO05-TEQg-1 w.w.) (p for trend=0.043), livestock products (from 0.133±0.298 to 0.035±0.043 pgWHO05-TEQ g-1 w.w.), eggs (from 0.221 ± 0.373 to 0.056 ± 0.048 pgWHO05-TEQ g-1 w.w.) (p for trend = 0.002), and dairy samples (from 0.066 ± 0.075 to 0.024 ± 0.026 pgWHO05-TEQ g-1 w.w.) (p for trend= 0.001). All lifetime average daily doses (LADD) were below provisional tolerable monthly intake (PTMI) but higher than the TWI for PCDD/Fs and DL-PCBs in food. The percentages of the contribution of each food group to the total dietary intake of TEQPCDD/F+PCB in different ambient air dispersion areas and age groups. The total daily intake of PCDD/Fs and DL-PCBs by Taiwanese differed between AQRs (0.188-0.397 pgWHO05-TEQ kg-1 b.w. day-1). The observed geographical variations were likely due to differences in food habits, cuisines, culture and levels of environmental contamination among various regions in Taiwan. By sensitivity analysis, we have identified the major contribution to LADD, which was the dioxin levels in marine fish, fresh water fish and fish related products, and followed by dioxin levels in duck eggs. In addition, marine and freshwater fish consumption rate accounts more than 10.2%. These major exposure variables was also consistent with the findings of total daily intake in different AQRs.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31801307

RESUMO

Existing food classification and description systems provide users with limited information related to exposure assessment. Our aim in this work is to propose a standardized food description facet called the Taiwan Food Recipe (TFR) system as an emerging tool for food composition, with detailed food ingredient information, including names, proportions, weights of uncooked and cooked foods, etc. The composite foods listed in the Taiwan Nutrition and Health Survey were collected into a list and as consumption data. The TFR system is intended to help analysts reduce potential estimation bias, where, for example, risk assessment results may be overestimated or underestimated due to the complexity of the composition in the composite foods. Based on a Taiwanese food database, we further illustrate and demonstrate how the TFR system can be applied to the assessment of risk of cadmium (Cd) exposure in rice ingredients in the composite food products. In the original system (HFDFC system), the composite food intakes used total weight to estimate the hazard index (HI) of cadmium in the exposure risk assessment, but the percentage of rice was not 100%. The proposed TFR system estimates the percentage of rice and actual intakes in composite foods. Fried rice, sushi, and rice balls in the study were the most common foods containing rice and had higher consumption rates among Taiwan's rice-based composite foods. The HIs of fried rice, sushi, and rice balls were 0.09, 0.10, and 0.13, respectively, in the HFDFC system. In the TFR system, the HIs of rice in fried rice, sushi, and rice balls were 0.06, 0.04 and 0.05, respectively. The HI of other components in fried rice, sushi, and rice balls were 0.03, 0.06 and 0.08, respectively. More precise HIs were thus shown. The TFR system contributes to global food classification and description systems by providing an appropriate, standardized, and generalized framework for exposure assessments.


Assuntos
Cádmio/análise , Exposição Dietética/análise , Contaminação de Alimentos/análise , Oryza/química , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Taiwan , Adulto Jovem
11.
Food Funct ; 10(6): 3324-3333, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31095144

RESUMO

The aim of the present study was to assess whether dietary advanced glycation end products (AGEs) induce testicular dysfunction. Using a BALB/c mouse model, AGE intake and serum levels were found to increase in AGE diet-treated mice relative to the controls. Histopathological damage was detected in the testes and epididymides of the AGE diet-induced mice. The total number of epididymal sperm decreased, and increased abnormal sperm rate was found in the mice. Moreover, the mice testes showed an increased level of the receptor for AGEs (RAGE) and malondialdehyde (MDA). Using a Sprague-Dawley rat model, AGE diet-induced rats showed 3- to 4-fold higher AGE intake than the controls. In these rats, higher serum and sperm MDA levels, decreased epididymal sperm numbers, and increased abnormal sperm rates were also observed. Silymarin, a natural AGE inhibitor, was found to restore these AGE-induced phenomena. Concluding from the above findings, dietary AGEs may promote testicular dysfunction.


Assuntos
Epididimo/citologia , Produtos Finais de Glicação Avançada/metabolismo , Espermatogênese , Espermatozoides/citologia , Testículo/citologia , Animais , Epididimo/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Ratos Sprague-Dawley , Receptor para Produtos Finais de Glicação Avançada/genética , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Contagem de Espermatozoides , Espermatozoides/metabolismo , Testículo/metabolismo
12.
J Food Drug Anal ; 26(4): 1312-1319, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30249330

RESUMO

Harmonization of national consumption data for international comparison is an important but challenging work, yet to date there is a lack of comparable food classification system that incorporates food description in Taiwan. In 2015, European Food Safety Authority (EFSA) released a new standardized food classification and description system called FoodEx2, which provides a flexible combination of classifications and descriptions. Based on FoodEx2 and a unique data set of daily food consumption offered by Taiwan Food Consumption Database, this study aims to provide a harmonized, food description incorporated, food classification system (HFDFC system) that captures all the useful details of food groups in exposure assessments. The HFDFC system was built according to six risk-assessment-related facets including food sources, processed products, cooking methods, manufacturers (brand), food additives and specialty foods. The HFDFC system includes 199 foods in the core list and 131 foods in the extended list. This study also compared the Acrylamide hazard index estimated under the HFDFC system with that under the National Food Consumption Database in Taiwan (NFCDT). The findings indicated that the HFDFC system provides useful and detailed information that helps the users to quickly identify food information in a harmonized manner and to reduce estimation bias. The HFDFC system is expected to facilitate global comparisons in the food risk assessment because it is built based upon EU Foodex2.


Assuntos
Acrilamida/análise , Contaminação de Alimentos/análise , Grãos Integrais/química , Adulto , Idoso , Animais , Feminino , Alimentos/classificação , Inocuidade dos Alimentos , Inquéritos Epidemiológicos , Humanos , Masculino , Carne/análise , Pessoa de Meia-Idade , Inquéritos Nutricionais , Medição de Risco , Taiwan , Adulto Jovem
13.
J Agric Food Chem ; 64(29): 5935-40, 2016 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-27396727

RESUMO

Papaya is an important fruit that provides a variety of vitamins with nutritional value and also holds some pharmacological properties, including immunomodulation. Genetically modified (GM) papaya plants resistant to Papaya ringspot virus (PRSV) infection have been generated by cloning the coat protein gene of the PRSV which can be used as a valuable strategy to fight PRSV infection and to increase papaya production. In order to assess the safety of GM papaya as a food, this subchronic study was conducted to assess the immunomodulatory responses of the GM papaya line 823-2210, when compared with its parent plant of non-GM papaya, Tainung-2 (TN-2), in Sprague-Dawley (SD) rats. Both non-GM and GM 823-2210 papaya fruits at low (1 g/kg bw) and high (2 g/kg bw) dosages were administered via daily oral gavage to male and female rats consecutively for 90 days. Immunophenotyping, mitogen-induced splenic cell proliferation, antigen-specific antibody response, and histopathology of the spleen and thymus were evaluated at the end of the experiment. Results of immunotoxicity assays revealed no consistent difference between rats fed for 90 days with GM 823-2210 papaya fruits, as opposed to those fed non-GM TN-2 papaya fruits, suggesting that with regard to immunomodulatory responses, GM 823-2210 papaya fruits maintain substantial equivalence to fruits of their non-GM TN-2 parent.


Assuntos
Carica/química , Alimentos Geneticamente Modificados/virologia , Doenças das Plantas/virologia , Plantas Geneticamente Modificadas/química , Potyvirus/fisiologia , Animais , Carica/genética , Carica/imunologia , Carica/virologia , Feminino , Frutas/química , Frutas/genética , Frutas/imunologia , Frutas/virologia , Análise de Perigos e Pontos Críticos de Controle , Masculino , Doenças das Plantas/imunologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/imunologia , Plantas Geneticamente Modificadas/virologia , Ratos , Ratos Sprague-Dawley
14.
J Food Drug Anal ; 24(3): 644-652, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-28911572

RESUMO

The levels of polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzofuran (PCDF) or polychlorinated biphenyl (PCB) in foodstuffs have decreased over the past decade in many countries. However, the trend for the levels of these compounds in foodstuffs in Taiwan remains unknown. In this study, we compared the distribution of PCDD/F and PCB in nine foodstuff categories acquired from Taiwan markets from 2004 to 2012. The levels expressed as World Health Organization toxic equivalents (WHO-TEQs) in the different foodstuffs tested were as follows: fish, average 0.463 pg WHO98-TEQ/g sample > seafood, 0.163 pg WHO98-TEQ/g > eggs, 0.150 pg WHO98-TEQ/g > oils, 0.126 pg WHO98-TEQ/g > meats, 0.095 pg WHO98-TEQ/g > dairy products, 0.054 pg WHO98-TEQ/g > cereals, 0.017 pg WHO98-TEQ/g > vegetables, 0.013 pg WHO98-TEQ/g > fruits, 0.009 pg WHO98-TEQ/g. Levels were particularly high in crab (average: 0.6 pg WHO98-TEQ/g sample (1.243 pg WHO98-TEQ/g sample) and large marine fish (0.6). In Taiwan, a decreasing trend of PCDD/Fs or dioxin-like PCBs (dl-PCBs) was observed in meat, dairy, eggs, and vegetables, whereas an elevated trend was observed in cereals or the levels were nearly equal in fruits and oils at alternative time shift. Dl-PCBs contributed to 60-65% toxicity equivalence levels in fish and seafood, but only to 13-40% in meat and cereal samples. The decreasing trend was consistent with the results in other countries; however, the trends in cereals, fruits, and oils were in contrast to previous results reported in other countries. Cereals and fruits are important crops in southern Taiwan, and the local pollution generated by industries or incinerators may seriously affect the distribution of PCDD/Fs and dl-PCBs. To ensure food safety, a risk assessment for residents living in different areas should be adopted for all food categories simultaneously in the future.


Assuntos
Contaminação de Alimentos , Animais , Dibenzofuranos Policlorados , Dioxinas , Bifenilos Policlorados , Dibenzodioxinas Policloradas , Taiwan
15.
J Agric Food Chem ; 63(4): 1286-1292, 2015 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-25578800

RESUMO

Genetically modified (GM) papaya plants resistant to infection by Papaya ringspot virus (PRSV) have been successfully generated by cloning the coat protein (CP) gene of PRSV to increase fruit production. In this study, the GM papaya line 823-2210 was used to conduct a 90-day feeding toxicity study and compared to its parent plant of non-GM papaya, Tainung-2 (TN-2) based on the experimental guidance reported by the European Food Safety Authority.1 Ten male and 10 female Sprague-Dawley albino rats were gavaged at low (1 g/kg bw) and high (2 g/kg bw) doses of non-GM and GM lyophilized papaya fruits for 90 days. Hematology, coagulation, biochemistry, urinalysis, and pathology were examined in all animals. Although some differences were found in feed consumption, hematology, and serum chemistry examinations between non-GM and GM papaya, the results were within historical control values and not considered biologically significant in rats. In addition, there were no treatment-related gross or microscopic lesions in male or female rats attributable to the non-GM or GM papaya fruit. This 90-day feeding study of GM papaya fruit did not reveal adverse effects in rats and indicates that GM papaya fruits may be substantially equivalent to their non-GM parent plants.

16.
J Agric Food Chem ; 61(7): 1585-96, 2013 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-23350793

RESUMO

The transgenic papaya is a valuable strategy for creating plants resistant to papaya ringspot virus (PRSV) infection and increasing production. This study was further performed to evaluate the comparative toxicity effects of the newly developed transgenic line of the fruits of two backcross transgenic papaya lines (2210 and 823) and one hybrid line (823-2210) and compare to their parent non-transgenic (TN-2) counterparts. The stability analysis of coat protein (CP) of PRSV was investigated using the digestion stability assays in simulated gastric fluid (SGF), simulated intestinal fluid (SIF), and bile salts to detect the CP fragments. Results revealed that the CP fragments were rapidly hydrolyzed in SGF and were undetectable in organs and gastrointestinal contents in rats. For the genotoxicity, three in vitro assays were conducted and exhibited that non-transgenic and backcross transgenic papaya fruits were negative. Moreover, a repeated animal feeding study was conducted by feeding 2 g/kg of body weight (bw) of non-transgenic and backcross transgenic papaya fruits for 28 days in rats. There were no biological or toxicological significances between non-transgenic and backcross transgenic papaya fruits in rats. The results demonstrated that the backcross transgenic papaya fruit can be recognized as an equivalent substitution for traditional papaya in food safety.


Assuntos
Carica/toxicidade , Frutas/toxicidade , Plantas Geneticamente Modificadas/toxicidade , Ração Animal , Animais , Carica/genética , Carica/virologia , Feminino , Frutas/genética , Frutas/virologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Plantas Geneticamente Modificadas/virologia , Potyvirus , Ratos , Ratos Sprague-Dawley
17.
J Sci Food Agric ; 91(12): 2271-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21618546

RESUMO

BACKGROUND: The effects of polished and dehulled Bacillus-fermented adlay on lipid metabolism, antioxidant status and intestinal microflora were examined in hyperlipidaemic hamsters fed a high-cholesterol diet. RESULTS: Hamsters administered Bacillus-fermented adlay experienced significantly reduced (P < 0.05) serum and hepatic total cholesterol (by 37-43% and 42-49% respectively) and triglyceride (by 22-27% and 30-35% respectively) levels compared with the high-cholesterol group. Lower low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratios in serum and increased cholesterol (by 47-52%) and triglyceride (by 40-47%) contents in faeces were also observed. Bacillus-fermented adlay lowered the levels of thiobarbituric acid-reactive substances, thus increasing total antioxidant and superoxide dismutase activities. In particular, polished Bacillus-fermented adlay had satisfactory antioxidant activity, similar to that of commercially available natto. Moreover, hamsters fed Bacillus-fermented adlay harboured greater populations of lactic acid bacteria, few coliforms and little Clostridium perfringens. CONCLUSION: This study has shown that changes in lipid metabolism, antioxidant status and intestinal microflora can be greatly modulated by Bacillus-fermented adlay, suggesting potential novel approaches to the treatment of primary cardiovascular and intestinal diseases.


Assuntos
Antioxidantes/administração & dosagem , Bacillus subtilis/metabolismo , Ceco/microbiologia , Coix/química , Suplementos Nutricionais , Metabolismo dos Lipídeos , Sementes/química , Animais , Antioxidantes/metabolismo , Clostridium perfringens/isolamento & purificação , Contagem de Colônia Microbiana , Cricetinae , Enterobacteriaceae/isolamento & purificação , Fezes/química , Fezes/microbiologia , Fermentação , Hiperlipidemias/sangue , Hiperlipidemias/metabolismo , Hiperlipidemias/prevenção & controle , Lactobacillales/isolamento & purificação , Lipídeos/sangue , Fígado/enzimologia , Fígado/metabolismo , Masculino , Mesocricetus , Distribuição Aleatória , Superóxido Dismutase/sangue , Superóxido Dismutase/metabolismo
18.
J Agric Food Chem ; 59(8): 3876-83, 2011 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-21410287

RESUMO

By introducing aprN into Lactococcus lactis NZ9000, the genetically modified L. lactis NZ9000/pNZPNK successfully expressed the nattokinase. The safety assessment of this novel strain was based on allergenicity of pepsin digestion stability and murine model serologic identity. Subjecting to the GM strain and host to pepsin digestion, the soluble fractions and cell debris were fast degraded completely. Feeding with ovalbumin resulted in significantly higher production of IgG1 and IgE as compared to that of L. lactis NZ9000/pNZPNK or L. lactis NZ9000. Further, the serum IgG2a level increased dose-dependently at week 2 and induced immune reaction toward Th1 pathway. Secretion of cytokines IL-4 and IL-10 fed with lactococci was significantly lower than that of the OVA group. L. lactis NZ9000/pNZPNK did not increase the proliferation of type 2 helper T cells in spleen or induce allergenicity in BALB/c mice. On the basis of the results, the new GM lactic acid bacterium is regarded as safe to use.


Assuntos
Alérgenos/imunologia , Modelos Animais de Doenças , Lactococcus lactis/imunologia , Organismos Geneticamente Modificados , Subtilisinas/imunologia , Alérgenos/genética , Animais , Sequência de Bases , Primers do DNA , Ensaio de Imunoadsorção Enzimática , Imunoglobulinas/sangue , Lactococcus lactis/enzimologia , Lactococcus lactis/genética , Camundongos , Pepsina A/metabolismo , Subtilisinas/genética
19.
J Biosci Bioeng ; 111(5): 554-6, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21330204

RESUMO

This study evaluated the potential free radical-scavenging and tyrosinase-inhibiting activities of extracts from sorghum distillery residue (SDR). The results demonstrated that methanol was a more efficient solvent for extracting the active components of SDR, and methanol extracts showed the highest radical-scavenging and tyrosinase-inhibiting activities.


Assuntos
Sequestradores de Radicais Livres/farmacologia , Monofenol Mono-Oxigenase/antagonistas & inibidores , Extratos Vegetais/farmacologia , Sorghum/química , Radicais Livres/metabolismo , Metanol/química , Solventes/química
20.
Biometals ; 24(4): 585-94, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21327478

RESUMO

Escherichia coli (E. coli) are the most common aerobic gram-negative bacilli in a normal intestinal tract. They cause most of the intra-abdominal infections, wound infections associated with abdominal surgery, and septicemia. Most of these infections are of endogenous intestinal origin. Lactoferrin (LF) is an iron-binding glycoprotein found in milk and various external secretions. This protein has been found to have a number of biological functions, including antimicrobial, anti-cancer, antioxidant, and immunomodulatory effects. Partial degradation of LF by pepsin can give rise to peptides termed lactoferricin (LFcin) with more potent antimicrobial activity. LF and LFcin have been shown to inhibit the growth of a number of pathogenic bacteria (including E. coli and antibiotic-resistant strains), fungi, and even viruses in both in vitro and in vivo studies. We previously demonstrated that both recombinant porcine LF (pLF) produced from yeast and a synthetic 20-residue porcine LFcin peptide exhibit antimicrobial activity in vitro. In one of our recent studies, we performed pathogen challenges, including pathogenic E. coli, Staphylococcus aureus and Candida albicans, of the digestive tract of a transgenic milk-fed animal model. The results showed that LF has broad spectrum antimicrobial activity in the digestive tract and protects the mucosa of the small intestine from injury. Our following study also revealed that pLF as a feedstuff additive enhances avian immunity, including antibody formation and cell-mediated immunity. All of these results suggest that LF could be a novel natural protein in the treatment and prevention of infections with E. coli or antibiotic-resistant bacteria strains.


Assuntos
Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Escherichia coli/tratamento farmacológico , Escherichia coli/efeitos dos fármacos , Ferro/metabolismo , Lactoferrina/metabolismo , Lactoferrina/uso terapêutico , Animais , Antibacterianos/imunologia , Antibacterianos/metabolismo , Escherichia coli/patogenicidade , Humanos , Lactoferrina/imunologia , Lactoferrina/farmacologia , Testes de Sensibilidade Microbiana
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