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1.
Ultrason Sonochem ; 76: 105625, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34147916

RESUMO

Ultrasound has a significant effect on the rate of various processes in food, perfume, cosmetic, pharmaceutical, bio-fuel, materials, or fine chemical industries, despite some shortcomings. Combination with other conventional or innovative techniques can overcome these limitations, enhance energy, momentum and mass transfer, and has been successfully demonstrated in many recent studies. Various ultrasound combined hybrid and innovative techniques are systematically summarized in this review for the first time. Ultrasound can be combined with diverse conventional techniques including Soxhlet, Clevenger, enzyme, hydrotropes, ionic liquids, Deep Eutectic Solvents (DES) or Natural Deep Eutectic Solvents (NADES), to enhance mixing and micro-mixing, reduced thermal and concentration gradients, and selective extraction. Moreover, combinations of ultrasound with other innovative techniques such as microwave, extrusion, supercritical fluid, subcritical and pressure liquids, Instant controlled pressure drop (DIC), Pulsed Electric Field (PEF), Ultra-Violet (UV) or Infra-Red (IR) radiations, Counter-current chromatography (CCC), or centrifugal partition chromatographs (CPC) can enable reduced equipment size, faster response to process control, faster start-up, increased production, and elimination of process steps. The theories and applications of these ultrasound combined hybrid and innovative techniques as well as their advantages and limitations are compared, and further perspectives are proposed. This review provides new insights into advances in ultrasound combined techniques and their application at research, educational, and industrial level in modern food and plant-based chemistry.


Assuntos
Produtos Biológicos/isolamento & purificação , Fracionamento Químico/métodos , Manipulação de Alimentos/métodos , Ondas Ultrassônicas
2.
J Appl Microbiol ; 130(2): 325-340, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32797725

RESUMO

Cold plasma technology is an efficient, environmental-friendly, economic and noninvasive technology; and in recent years these advantages placed this novel technology at the centre of diverse studies for food industry applications. Dried food ingredients including spices, herbs, powders and seeds are an important part of the human diet; and the growing demands of consumers for higher quality and safe food products have led to increased research into alternative decontamination methods. Numerous studies have investigated the effect of nonthermal plasma on dried food ingredients for food safety and quality purposes. This review provides critical review on potential of cold plasma for disinfection of dried food surfaces (spices, herbs and seeds), improvement of functional and rheological properties of dried ingredients (powders, proteins and starches). The review further highlights the benefits of plasma treatment for enhancement of seeds performance and germination yield which could be applied in agricultural sector in near future. Different studies applying plasma technology for control of pathogens and spoilage micro-organisms and modification of food quality and germination of dried food products followed by benefits and current challenges are presented. However, more systemic research needs to be addressed for successful adoption of this technology in food industry.


Assuntos
Ingredientes de Alimentos/normas , Qualidade dos Alimentos , Alimentos em Conserva/normas , Gases em Plasma , Manipulação de Alimentos , Ingredientes de Alimentos/análise , Ingredientes de Alimentos/microbiologia , Inocuidade dos Alimentos , Alimentos em Conserva/análise , Alimentos em Conserva/microbiologia , Humanos
3.
Carbohydr Polym ; 248: 116784, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32919572

RESUMO

The macroalgal hydrocolloid industry is a rapidly growing industry with an annual growth in the global production of 2-3 %. Hydrocolloids from macroalgae are mainly in the form of polysaccharides with other nutrients, such as vitamins, minerals, and proteins. Due to its potential industrial applications, macroalgae have been used as raw materials for hydrocolloids extraction. Compared to the conventional extraction methods, emerging innovative assisted extraction technologies (e.g., Ultrasound/Microwave assisted extraction) have been developed to maximise the extraction yields, efficiency and thereby, maintaining sustainability along the process. These novel techniques are considered as clean and green strategies, with a potential for a large-scale production; thus, avoiding or reducing the use of chemicals. However, more research is required to establish their mechanism of action in order to finally implement them at industrial level. This paper reviews the most relevant strategies and technologies involved in the production of hydrocolloids from macroalgae.


Assuntos
Coloides/isolamento & purificação , Tecnologia de Alimentos/métodos , Alimentos , Micro-Ondas , Polissacarídeos/isolamento & purificação , Alga Marinha/química , Proteínas de Algas/isolamento & purificação , Produtos Biológicos/isolamento & purificação , Difusão de Inovações , Tecnologia de Alimentos/instrumentação , Tecnologia de Alimentos/tendências , Humanos
4.
J Appl Microbiol ; 129(5): 1248-1260, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32358824

RESUMO

AIMS: The study aimed to investigate the inactivation efficacy and mechanisms of plasma activated water (PAW) on selected bacteria in planktonic state. METHODS AND RESULTS: Plasma activated water was generated using an atmospheric cold plasma jet at 15, 22 and 30 kV for 5 min. Escherichia coli, Listeria innocua, Staphylococcus aureus, Aeromonas hydrophila, Pseudomonas fluorescens and Shewanella putrefaciens were selected as the representative bacterial species. Each bacterial suspension was inoculated into PAW immediately after generation, and the viable counts at different exposure times of 0·5, 1, 3, 5 and 24 h during 4°C storage were measured to determine the inactivation efficacy. Scanning electron microscopy images of the bacteria were conducted to examine the structural changes. Physicochemical properties of PAW, including pH, conductivity, oxidation reduction potential (ORP), and reactive species of H2 O2 , NO2 - and NO3 - were measured. The results demonstrated that inactivation efficacy was in positive correlation with voltage and exposure time. Gram-negative bacteria were more susceptible to PAW than Gram-positive bacteria. Morphology damage was observed for all the bacterial species. PAW was significantly acidified, conductivity and ORP were significantly increased, and reactive species were detectable after 48 h. CONCLUSIONS: This study offered a better understanding of the inactivation mechanisms of PAW, and the inactivation efficacy can be affected by voltage, exposure time and bacterial species. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrated the potential usage of PAW as an alternative disinfectant.


Assuntos
Bactérias/efeitos dos fármacos , Desinfetantes/farmacologia , Gases em Plasma/química , Água/farmacologia , Bactérias/classificação , Desinfetantes/química , Radicais Livres/análise , Radicais Livres/farmacologia , Concentração de Íons de Hidrogênio , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Especificidade da Espécie , Água/química , Microbiologia da Água
5.
Indian J Med Res ; 141(5): 576-83, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26139774

RESUMO

BACKGROUND & OBJECTIVES: Malaria is a serious public health concern in several parts of India, particularly in tribal areas of Madhya Pradesh (MP). Dindori district inhabitated by Baiga tribe, contributes about 15 per cent to the total malaria burden in MP. The tribal and other local inhabitants believe in magico-religious treatment of malaria and use modern health facilities only as second line of treatment. The present study was planned in the villages of one of the particularly vulnerable tribal group of MP, the Baigas. The objective of the study was to generate awareness and utilization of health services for malaria by establishing a communication strategy using local students and unemployed youths as agents of change. METHODS: The study was undertaken in 47 villages and the need based IEC (information, education and communication) intervention was evaluated within four months of initiation by adopting before and after with control design. For both baseline and resurvey the households covered each time were 2350. RESULTS: The baseline data generated revealed that around 53 per cent of the people in the study villages were aware of malaria. Among the non Baigas, 59 per cent were aware of malaria, while among the Baigas it was 49 per cent. IEC intervention could raise the level of awareness to malaria significantly with a net intervention effect of 23 per cent. The IEC intervention also improved the utilization of modern health services significantly. INTERPRETATION & CONCLUSIONS: The IEC strategy designed by using local children and youths was effective as the malaria was on decline in the study area. The same strategy with necessary modifications may be replicated in other areas pandemic for malaria.


Assuntos
Comunicação , Serviços de Saúde , Malária Falciparum/epidemiologia , Grupos Populacionais , Humanos , Índia , Malária Falciparum/parasitologia , Malária Falciparum/terapia , Plasmodium falciparum/patogenicidade
6.
Ultrason Sonochem ; 21(1): 409-14, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23838287

RESUMO

The use of ultrasound to enhance the transport phenomena in food processes has been well recognised in recent times. The objective of this study was to evaluate the effect of sonication on hydration rate and pasting profile of navy beans. The hydration kinetics for control and ultrasound assisted soaking was mathematically described using mechanistic (Fickian diffusion) and empirical (Peleg's equation, Weibull model and First Order equation) models. Ultrasound enhanced the rate of hydration which was evident from the plot of kinetic data and model parameters. The effective diffusivities for water transport without and with ultrasound application were estimated to be 1.36×10(-10) m(2)/s and 2.19×10(-10) m(2)/s respectively, considering Fickian diffusion. The Weibull model was concluded to best predict the hydration kinetics of navy beans in an ultrasonic field. Significant increase in peak viscosity of sonicated bean powder was observed compared to control.


Assuntos
Phaseolus/química , Sonicação , Difusão , Hidrólise , Cinética , Pomadas
7.
Cell Death Dis ; 4: e461, 2013 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-23328668

RESUMO

Dynamic variations in mitochondrial shape have been related to function. However, tools to automatically classify and enumerate mitochondrial shapes are lacking, as are systematic studies exploring the relationship of such shapes to mitochondrial stress. Here we show that during increased generation of mitochondrial reactive oxygen species (mtROS), mitochondria change their shape from tubular to donut or blob forms, which can be computationally quantified. Imaging of cells treated with rotenone or antimycin, showed time and dose-dependent conversion of tubular forms to donut-shaped mitochondria followed by appearance of blob forms. Time-lapse images showed reversible transitions from tubular to donut shapes and unidirectional transitions between donut and blob shapes. Blobs were the predominant sources of mtROS and appeared to be related to mitochondrial-calcium influx. Mitochondrial shape change could be prevented by either pretreatment with antioxidants like N-acetyl cysteine or inhibition of the mitochondrial calcium uniporter. This work represents a novel approach towards relating mitochondrial shape to function, through integration of cellular markers and a novel shape classification algorithm.


Assuntos
Algoritmos , Mitocôndrias/classificação , Acetilcisteína/farmacologia , Antibacterianos/farmacologia , Antimicina A/análogos & derivados , Antimicina A/farmacologia , Antioxidantes/farmacologia , Cálcio/metabolismo , Linhagem Celular , Citometria de Fluxo , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Rotenona/farmacologia
8.
Appetite ; 59(2): 341-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22634197

RESUMO

Capsaicinoids are a group of chemicals found in chilli peppers, with bioactive properties. The purpose of this study is to systematically review research investigating the potential benefits capsaicinoid compounds may have in relation to weight management. Medical databases were searched and 90 trials found, 20 of which were selected for inclusion, involving 563 participants. Three main areas of potential benefit for weight management were found: (1) increased energy expenditure; (2) increased lipid oxidation and (3) reduced appetite. Trial duration, dosage and sized varied, though trials were generally of high quality with a low risk of bias. It was observed that consumption of capsaicinoids increases energy expenditure by approximately 50 kcal/day, and that this would produce clinically significant levels of weight loss in 1-2 years. It was also observed that regular consumption significantly reduced abdominal adipose tissue levels and reduced appetite and energy intake. The mechanism of action is not presently fully understood, although it is well accepted much of the effects are caused by stimulation of the TRPV1 receptor. While capsaicinoids are not a magic bullet for weight loss, the evidence is that they could play a beneficial role, as part of a weight management program.


Assuntos
Capsaicina/análogos & derivados , Capsaicina/farmacologia , Capsicum/química , Extratos Vegetais/farmacologia , Apetite/efeitos dos fármacos , Bases de Dados Factuais , Ingestão de Energia , Metabolismo Energético , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Redução de Peso
9.
Indian J Tuberc ; 59(4): 243-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23342547

RESUMO

A community-based cross-sectional survey was carried out amongst the tribal population of Jhabuain Madhya Pradesh. A total of 1385 individuals from randomly selected villages were interviewed using structured questionnaire. Eighty five per cent respondents had knowledge of the symptoms of tuberculosis. About a quarter of the respondents were not aware of any method for preventing TB. Though majority of the respondents (68.2%) stated that TB is a curable disease, most of them (67.2%) were not aware of the DOTS programme. The study emphasizes the need for extensive health education programme to create awareness about tuberculosis in tribal population of the region.


Assuntos
Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Grupos Populacionais , Tuberculose/epidemiologia , Adulto , Estudos Transversais , Feminino , Humanos , Incidência , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Inquéritos e Questionários , Adulto Jovem
10.
Ultrason Sonochem ; 18(5): 1172-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21486706

RESUMO

The effect of ultrasound and blanching pretreatments on polyacetylene (falcarinol, falcarindiol and falcarindiol-3-acetate) and carotenoid compounds of hot air and freeze dried carrot discs was investigated. Ultrasound pretreatment followed by hot air drying (UPHD) at the highest amplitude and treatment time investigated resulted in higher retention of polyacetylenes and carotenoids in dried carrot discs than blanching followed by hot air drying. Freeze dried samples had a higher retention of polyacetylene and carotenoid compounds compared to hot air dried samples. Color parameters were strongly correlated with carotenoids (p<0.05). This study shows that ultrasound pretreatment is a potential alternative to conventional blanching treatment in the drying of carrots.


Assuntos
Carotenoides/análise , Daucus carota/química , Daucus carota/efeitos da radiação , Dessecação/métodos , Liofilização , Poli-Inos/química , Sonicação/métodos , Ar , Manipulação de Alimentos/métodos , Tecnologia de Alimentos/métodos , Calefação/métodos , Poli-Inos/efeitos da radiação , Doses de Radiação
11.
Int J Food Microbiol ; 142(1-2): 53-9, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20576302

RESUMO

Many of the documented outbreaks of Cronobacter sakazakii have been linked to infant formula. The aims of this work are to monitor the inactivation kinetics of C.sakazakii NCTC 08155 and ATCC 11467 and to determine quantitatively the effectiveness of ultrasonic treatments as an alternative to heat processing of reconstituted infant milk formula before feeding of infants at highest risk. Inactivation studies of C. sakazakii inoculated in reconstituted infant formula were performed at the combined conditions of temperature, i.e., 25 degrees C, 35 degrees C, 50 degrees C and amplitude, i.e., 24.4, 30.5, 42.7, 54.9, 61 microm and the kinetics were described by a range of inactivation models. The dependency of the specific inactivation rate with respect to the product of temperature and amplitude was described by a modified Bigelow type model. Ultrasound combined with temperature was efficient to reduce significantly the microbial levels of C. sakazakii. C. sakazakii strain NCTC 08155 was at the same range of temperature and amplitude resistance as strain ATCC 11467. Application of ultrasound is an alternative process for the production of safe reconstituted infant formula. This study contributes on the quantitative assessment of the resistance of C. sakazakii.


Assuntos
Enterobacteriaceae/crescimento & desenvolvimento , Manipulação de Alimentos/métodos , Microbiologia de Alimentos , Fórmulas Infantis/química , Viabilidade Microbiana , Contaminação de Alimentos/prevenção & controle , Manipulação de Alimentos/instrumentação , Manipulação de Alimentos/normas , Temperatura
12.
Int J Food Microbiol ; 137(1): 116-20, 2010 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-19906456

RESUMO

Power ultrasound is recognised as a potential non thermal technique to inactivate microorganisms pertinent to fruit juices. In this study, the effect of sonication on the resistance of yeast (Pichia fermentans) in tomato juice was investigated. Tomato juice samples were sonicated at amplitude levels ranging from 24.4 to 61.0mum at a constant frequency of 20kHz for different treatment times (2 to 10min) and pulse durations of 5s on and 5s off. Significant reductions (p<0.05) were observed at higher amplitudes and processing times. Yeast inactivation was found to follow the Weibull model with a high regression coefficient (R(2)>0.98) and low RMSE (<0.51). The desired 5 log reductions (D(5) value) and shape factors were found to correlate exponentially with amplitude level. Results presented in this study show that sonication alone is an effective process to achieve the desired level of yeast inactivation in tomato juice.


Assuntos
Bebidas/microbiologia , Manipulação de Alimentos/métodos , Microbiologia de Alimentos , Pichia , Solanum lycopersicum/microbiologia , Sonicação/métodos , Contagem de Colônia Microbiana , Manipulação de Alimentos/instrumentação , Modelos Biológicos , Pichia/isolamento & purificação , Sonicação/instrumentação , Fatores de Tempo
13.
Ultrason Sonochem ; 17(3): 598-604, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20015673

RESUMO

Grape juice samples were sonicated with processing variables of amplitude level (24.4-61.0microm) and treatment time (0-10min) at a constant frequency of 20kHz and pulse durations of 5s on and 5s off. A full factorial experimental design with regression modeling was employed to investigate the main effects of amplitude level and treatment time on anthocyanins and color parameters. Significant effects of sonication on major anthocyanins cyanidin-3-O-glucosides (CA), malvanidin-3-O-glucosides (MA) and delphinidin-3-O-glucosides (DA), color values (L*, a*, b*) and color index (CI) were observed. Prediction models were found to be significant (p<0.05) with low standard errors and high coefficients of determination (R(2)). Model predictions for critical quality parameters of anthocyanins (CA; MA; DA), color values (L*, a*, b*), TCD and CI inactivation were closely correlated to the experimental results obtained. Significant retention of anthocyanin content in grape juice was observed for CA (97.5 %); MA (48.2 %) and DA (80.9%) during sonication. CI and other color combinations (L*a*b*, L*a*/b* and L*b*/a*) were found to be strongly correlated with anthocyanin content. This study shows that sonication could be employed for as a preservation technique for fruit juice processing where anthocyanin retention is desired.


Assuntos
Antocianinas/química , Bebidas , Pigmentação , Sonicação , Vitis/química , Cor , Análise de Regressão
14.
J Food Sci ; 75(7): M437-43, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21535553

RESUMO

Traditionally, ozone processing within the food industry has focused on solid foods by either gaseous treatment or washing with ozonized water. However, with the FDA's approval of ozone as a direct additive to food, the potential for liquid applications has emerged. This study investigates the effect of ozone processing on microbial inactivation (E. coli ATCC 25922 and NCTC 12900) and quality parameters (color, phenolic content) of cloudy apple juice. Apple juice samples were ozonated at room temperature (20 ± 1.5 °C) with a generated ozone concentration of 0.048 mg O(3) at a constant flow rate of 0.12 L/min and treatment time of 0 to 10 min. E. coli inactivation kinetics in apple juice were described quantitatively by using the Shoulder log-linear and the Weibull model. Ozone treatment of E. coli in apple juice demonstrate that a desired 5 log reduction can be achieved within 5 min. Apple juice color (L*, a*, and b*) and total phenols were significantly affected by ozone concentration and treatment time.


Assuntos
Bebidas/análise , Bebidas/microbiologia , Conservantes de Alimentos/farmacologia , Malus/química , Malus/microbiologia , Ozônio/farmacologia , Cromatografia Líquida de Alta Pressão , Cinamatos/análise , Contagem de Colônia Microbiana , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Flavonoides/análise , Conservantes de Alimentos/efeitos adversos , Conservantes de Alimentos/química , Frutas/química , Frutas/microbiologia , Concentração de Íons de Hidrogênio , Cinética , Viabilidade Microbiana , Modelos Biológicos , Concentração Osmolar , Ozônio/efeitos adversos , Ozônio/química , Fenóis/análise , Pigmentação/efeitos dos fármacos , Polifenóis , Controle de Qualidade , Estresse Fisiológico
15.
Food Chem Toxicol ; 47(11): 2824-9, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19733609

RESUMO

Grape juice samples were ozonated with processing variables of ozone concentration (1.6-7.8% w/w) and treatment time (0-10 min). Effects of processing variables on grape juice color values (L, a and b) and anthocyanins were determined. The changes in lightness (L) values and total color difference (TCD) values were fitted well to zero-order kinetics whereas, a and b followed first-order kinetics. Three major anthocyanins were observed in the grape juice namely cyanidin-3-O-glucoside (Cy3Gl, 133.9 mg/L), delphinidin-3-O-glucoside (Dy3Gl, 21.4) and malvidin-3-O-glucoside (My3Gl, 3.2mg/L). Significant reductions in anthocyanin content were observed during ozonation. During ozonation Cy3Gl was found to be stable compared to Dy3Gl and My3Gl. Changes in Cy3Gl were fitted well to the fraction conversion model. The results presented in this study indicate that both color and anthocyanin content are significantly affected during ozone processing. Thus, the effects of ozonation on the grape juice should be considered by processors prior to its adoption as a preservation technique.


Assuntos
Antocianinas/química , Bebidas/análise , Cor , Ozônio , Vitis/química , Estrutura Molecular
16.
Trop Med Int Health ; 13(11): 1372-7, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18983281

RESUMO

OBJECTIVE: To estimate the annual risk of tuberculosis infection (ARTI) among tribal children of Madhya Pradesh, central India. METHODS: Community-based, cross-sectional tuberculin survey among children aged 1-9 years in the tribal population of Madhya Pradesh. Multistage stratified cluster sampling was used to select a representative random sample of villages predominated by tribal population from selected districts. A total of 4802 children were tuberculin-tested with 1TU of PPD RT 23 and the reaction sizes read after 72 h. RESULTS: A total of 3062 (64%) children had no BCG scar. The frequency distribution of children by reaction sizes indicated a fair mode at 18 mm in the right hand side of the distribution. By mirror-image technique, the prevalence of infection among children with no recognizable BCG scar was estimated as 6.8% (95% CI: 4.8-8.9%). The ARTI was computed as 1.3% (0.9-1.7%). The corresponding figures for children irrespective of scar status were 7.1% (95% CI: 5.5-8.8%) and 1.3% (1.0-1.7%) respectively. CONCLUSIONS: The risk of tuberculosis infection in tribal population of Madhya Pradesh, central India is not different from other areas of the country. There is, however, a need to further intensify tuberculosis control measures on a sustained and long-term basis.


Assuntos
Tuberculose/etnologia , Adjuvantes Imunológicos/administração & dosagem , Vacina BCG/administração & dosagem , Criança , Pré-Escolar , Cicatriz/imunologia , Análise por Conglomerados , Estudos Transversais , Atenção à Saúde/estatística & dados numéricos , Feminino , Humanos , Índia/epidemiologia , Índia/etnologia , Lactente , Masculino , Prevalência , Medição de Risco , Saúde da População Rural , Distribuição por Sexo , Fatores Socioeconômicos , Teste Tuberculínico/estatística & dados numéricos , Tuberculose/diagnóstico , Tuberculose/imunologia
17.
J Agric Food Chem ; 56(21): 10071-7, 2008 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-18828602

RESUMO

Strawberry juice samples were sonicated at amplitude levels ranging from 40 to 100% at a constant frequency of 20 kHz for treatment times (2-10 min) and pulse durations of 5 s on and 5 s off. Sonication was found to reduce anthocyanin and ascorbic acid contents by 3.2 and 11%, respectively, at the maximum treatment conditions. Response surface methodology (RSM) based on a two-factor, five-level central composite design was employed to determine the effect of amplitude level and treatment time on anthocyanins (P3G), ascorbic acid (AA) content, and color values (L*, a*, and b*). The model predictions for the selected nutritional and quality parameters were closely correlated to the experimental results. RSM was demonstrated to be an effective technique to model the effect of sonication on strawberry juice quality while minimizing the number of experiments required.


Assuntos
Antocianinas/análise , Ácido Ascórbico/análise , Bebidas/análise , Fragaria/química , Antioxidantes/análise , Frutas/química , Modelos Biológicos , Sonicação
18.
Trans R Soc Trop Med Hyg ; 102(9): 898-904, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18632124

RESUMO

A cross-sectional tuberculin survey was carried out to estimate the prevalence of tuberculous infection and the annual risk of tuberculosis infection (ARTI) among children of Saharia, a primitive ethnic group in Madhya Pradesh, Central India. A total of 1341 children aged 1-9 years were subjected to tuberculin testing with 1 TU of PPD RT 23 and the reaction sizes were read after 72 h. The proportion of BCG scar-positive children was 34.6%. The frequency distribution of children by reaction sizes indicated a clear-cut anti-mode at 11 mm and a mode at 18 mm at the right-hand side of the distribution. The prevalence of infection among children irrespective of BCG scar was estimated as 20.4% (95% CI 18.2-22.5%) and the ARTI was 3.9% (95% CI 3.5-4.3%). The corresponding figures were 21.1% (95% CI 18.3-23.8%) and 3.9% (95% CI 3.4-4.5%) among BCG scar-negative children and 19.0% (95% CI 15.4-22.5%) and 4.0% (95% CI 3.2-4.8%) among BCG scar-positive children. The findings of the present study show a high prevalence of tuberculous infection and high ARTI in this primitive ethnic group. There is an urgent need to further intensify tuberculosis control measures on a sustained and long-term basis in this area.


Assuntos
Teste Tuberculínico/estatística & dados numéricos , Tuberculose/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Índia/epidemiologia , Lactente , Masculino , Mycobacterium bovis/imunologia , Prevalência , Medição de Risco , Saúde da População Rural
19.
J Agric Food Chem ; 56(7): 2423-8, 2008 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-18321054

RESUMO

The effects of sonication on pH, degrees Brix, titratable acidity (TA), cloud, browning index, and color parameters ( L*, a*, and b*) of freshly squeezed orange juice samples were studied. Ultrasonic intensity (UI) levels of 8.61, 9.24, 10.16, 17.17, and 22.79 W/cm2 and treatment times of 0 (control), 2, 4, 6, 8, and 10 min were investigated. No significant changes in pH, degrees Brix, and TA ( p < 0.05) were found. Cloud value, browning index, and color parameters were significantly affected by ultrasonic intensity and treatment time. Changes in cloud value followed first-order kinetics, whereas browning index, L*, a*, and b* values followed zero-order kinetics. Reaction rate constants were linearly correlated ( R2 > 0.90) to ultrasonic intensity.


Assuntos
Bebidas/análise , Citrus sinensis/química , Conservação de Alimentos/métodos , Frutas/química , Concentração de Íons de Hidrogênio , Cinética , Reação de Maillard , Sonicação
20.
Ann Trop Med Parasitol ; 101(5): 409-13, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17550646

RESUMO

Although cercarial dermatitis is an emerging disease world-wide, cases of such dermatitis may often go undiagnosed, especially in communities that are affected by various skin infections. Between August 2001 and July 2002, 1336 individuals from tribal villages in central India were examined for dermatitis. Skin scrapings were collected and examined for Sarcoptes scabiei and each subject's response to antiscabies treatment was recorded. Freshwater snails were collected from the local ponds used for bathing, and examined for cercariae. The recorded prevalence of dermatitis ranged between 2.1% and 12.5% during the study year, peaking at the end of winter (February-March) and during the rainy season (August-October). Snail positivity for cercariae peaked in the rainy season. The prevalence and the severity of dermatitis were both higher in children than in adults. As most recorded cases of dermatitis were associated with a rash that developed soon after bathing in the local pond, all the skin scrapings were negative for itch mites, and the response to antiscabies treatment was poor, most if not all of the dermatitis observed was probably cercarial. Cercarial dermatitis therefore appears to be a significant health problem among the tribal populations of central India.


Assuntos
Dermatite/epidemiologia , Esquistossomose/epidemiologia , Dermatopatias Parasitárias/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Animais , Criança , Dermatite/parasitologia , Feminino , Água Doce/parasitologia , Humanos , Índia/epidemiologia , Masculino , Prevalência , Saúde da População Rural , Escabiose/epidemiologia , Esquistossomose/parasitologia , Estações do Ano , Distribuição por Sexo , Pele/parasitologia , Dermatopatias Parasitárias/parasitologia , Caramujos
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