Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Ecotoxicology ; 31(9): 1426-1440, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36301372

RESUMO

Pyriproxyfen is a pyridine-based insecticide used for pest control in fruits and vegetables. It is a potent endocrine disruptor and hormone imitator. Considering its potential hazards to non-target organisms and the associated environment, a lab study was conducted for assessing persistence, mobility in sandy loam soil and associated risk to various non-target organisms and soil enzymes. Pyriproxyfen formulation was applied at 0.05 and 0.10 µg g-1 soil which was equivalent to recommended and double dose of 100 and 200 g a.i. ha-1, respectively. Three methods namely QuEChERS, liquid-solid extraction (LSE) and matrix solid phase dispersion (MSPD) were compared for achieving efficient sample preparation. MSPD was applied for final analysis as it gave better recoveries (94.2 to 104.3%) over other methods with limits of detection and quantification (LOD and LOQ) as 0.0001 and 0.0005 µg g-1, respectively. Dissipation followed first order kinetics with half-lives of 7.6 and 8.2 days in both doses but residues retained over 45 days in soil. Leaching studies conducted at 50 and 100 µg of pyriproxyfen showed extremely poor leaching potential. Retention of over 90% residues in top 5 cm soil surface indicated minimal threat of ground and surface water contamination. Toxicological study demonstrated very different behaviour toward different enzymatic activities. Pyriproxyfen was relatively toxic for alkaline phosphatase and fluorescein diacetate hydrolase enzymes. ß-glucosidase activity was triggered whereas arylsulfatase activity remained unaffected. Unacceptable risk to soil invertebrates at double dose application clearly indicated that its longer persistence in soil could be toxic to other non-target organisms and needs further investigations.


Assuntos
Inseticidas , Poluentes do Solo , Solo/química , Inseticidas/toxicidade , Inseticidas/análise , Ecossistema , Poluentes do Solo/análise , Piridinas/toxicidade
2.
Environ Sci Pollut Res Int ; 29(46): 69294-69326, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35978242

RESUMO

Water is necessary for the survival of life on Earth. A wide range of pollutants has contaminated water resources in the last few decades. The presence of contaminants incredibly different dyes in waste, potable, and surface water is hazardous to environmental and human health. Different types of dyes are the principal contaminants in water that need sudden attention because of their widespread domestic and industrial use. The toxic effects of these dyes and their ability to resist traditional water treatment procedures have inspired the researcher to develop an eco-friendly method that could effectively and efficiently degrade these toxic contaminants. Here, in this review, we explored the effective and economical methods of metal-based nanomaterials photocatalytic degradation for successfully removing dyes from wastewater. This study provides a tool for protecting the environment and human health. In addition, the insights into the transformation of solar energy for photocatalytic reduction of toxic metal ions and photocatalytic degradation of dyes contaminated wastewater will open a gate for water treatment research. The mechanism of photocatalytic degradation and the parameters that affect the photocatalytic activities of various photocatalysts have also been reported.


Assuntos
Poluentes Ambientais , Nanoestruturas , Poluentes Químicos da Água , Catálise , Corantes , Humanos , Águas Residuárias , Poluentes Químicos da Água/análise
3.
Front Nutr ; 9: 942524, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35990328

RESUMO

Whey and casein proteins, in particular, have shown considerable promise in replacing fossil-based plastics in a variety of food applications, such as for O2 susceptible foods, thereby, rendering milk proteins certainly one of the most quality-assured biopolymers in the packaging discipline. Properties like excellent gas barrier properties, proficiency to develop self-supporting films, adequate availability, and superb biodegradability have aroused great attention toward whey and other milk proteins in recent years. High thermal stability, non-toxicity, the ability to form strong inter cross-links, and micelle formation, all these attributes make it a suitable material for outstanding biodegradability. The unique structural and functional properties of milk proteins make them a suitable candidate for tailoring novel active package techniques for satisfying the needs of the food and nutraceutical industries. Milk proteins, especially whey proteins, serve as excellent carriers of various ingredients which are incorporated in films/coatings to strengthen barrier properties and enhance functional properties viz. antioxidant and antimicrobial. In this review, the latest techniques pertaining to the conceptualization of active package models/ systems using milk proteins have been discussed. Physical and other functional properties of milk protein-based active packaging systems are also reviewed. This review provides an overview of recent applications of milk protein-sourced active edible packages in the food packaging business.

4.
J Food Sci Technol ; 56(4): 2010-2015, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30996435

RESUMO

The present study was undertaken to evaluate physico-chemical composition and to study the effect of processing on phytochemical contents and nutritional components of anola juice prepared from Banarasi cultivar. Aonla juice pasteurized at 90 °C for 1 min showed better retention of phytochemicals as well as sensory characteristics. Methanol was used as a solvent for extraction of phytochemicals and reversed phase high performance liquid chromatography was performed to identify and quantify the phytochemical contents in juice extract. The pasteurized juice extract contained gallic acid, ethyl gallate, ellagic acid and quercetin 79.12, 0.29, 112.11 and 1.32 mg/100 g, respectively. Ascorbic acid content in juice extract was 155.04 mg/100 g. The storage study of aonla juice was conducted at refrigeration (4 °C) and ambient condition (25-40 °C).

5.
J Food Sci Technol ; 56(4): 2278-2286, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30996461

RESUMO

Methanolic, ethanolic and ethyl acetate extracts of five aonla varieties were analyzed for phytochemical characterization using RP-HPLC. Five compounds viz. ascorbic acid, gallic acid, ellagic acid, ethyl gallate and quercetin were identified in aonla extracts by RP-HPLC at 270 nm. Significant variations were observed in amount of identified phytochemical among the varieties. The highest level of phytochemical was observed in methanolic extract of variety Desi followed by varieties Kanchan, NA-7, Banarasi and Chakaiya. Among the solvent, methanol extracted the maximum phytochemicals while yield was least in ethyl acetate extract of aonla varieties. Gallic acid and ellagic acid were the most abundant phenolic compounds in extracts of aonla varieties. Ellagic acid (349.51 mg/100 g) and gallic acid (233.49 mg/100 g) were found maximum in methanolic extract of Desi variety. Results of the present study suggested that aonla is a good source of phenolic and flavonoid compounds.

6.
J Food Sci Technol ; 55(8): 3135-3143, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30065424

RESUMO

Drying kinetics and effects of drying on nutritional properties of 5 varieties of aonla were investigated using cabinet dryer. Thin shreds of aonla were spread in a layer in dryer and dried at varying temperature of 40, 50 and 60 °C till constant weight attained. Thin layer Newton model was proposed to study drying kinetic of aonla varieties. Degradation in TPC (total phenolic content) and ascorbic acid content were studied at varying temperature. Total phenolic and ascorbic acid content were retained maximum at 50 °C and higher values of R2 and the lowest value of root mean square error (RMSE), Chi square and mean biased error (MBE) for all varieties indicated that Newton model appropriately described the drying curve of aonla. Among the varieties, variety Banarasi had maximum value of R2 (0.993) and the lowest values for RMSE (0.039), Chi square (0.018) and MBE (0.001) at 50 °C. Reduction was observed in ascorbic acid, reducing sugar, polyphenol content and pectin content of aonla varieties during drying process. From study, it was observed that drying of aonla at 50 °C was best in terms of higher retention of TPC and ascorbic acid and Newton model was found suitable to explain drying pattern within temperature range under study.

7.
Syst Appl Microbiol ; 40(7): 458-467, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28967456

RESUMO

The species "Bacillus aminovorans" was categorized as species Incertae Sedis meaning taxa with uncertain taxonomic position because of insufficient description of phenotypic properties and lack of understanding of its phylogenetic relationship (Claus and Berkeley [5]). In this study two strains "B. aminovorans" DSM 1314T and DSM 4337 were phenotypically and phylogenomically analyzed. The strains are Gram-staining-positive, spore forming rods and unable to utilize/ferment most of the sugars tested except glucose. The major fatty acids are anteiso-C15:0 and iso-C15:0. The major polar lipids are diphosphatidylglycerol, phosphatidylglycerol and an aminophosphoglycolipid. The cell wall peptidoglycan is of A1γ type with meso-Dpm as the diamino acid. The menaquinone type present is MK-6. The G+C content of the genomic DNA of the type strain is 40.8mol%. These characteristics were found to be in line with description of the genus Domibacillus. Moreover phylogenetic analysis based on 16S rRNA gene sequence retrieved "B. aminovorans" within the genus Domibacillus with D. antri XD 80T as the closest relative. Additionally genome sequencing of the strains and their comparison with whole genome sequences of other Domibacillus spp. confirmed their distinctiveness and separate species status within the genus based on parameters of genome to genome distance calculator (GGDC) and average nucleotide identity (ANI) values. Therefore a novel species Domibacillus aminovorans sp. nov. (DSM 1314T=LMG 16796T) is proposed.


Assuntos
Bacillus/classificação , Bacillus/genética , Esporos Bacterianos/fisiologia , Técnicas de Tipagem Bacteriana , Composição de Bases/genética , DNA Bacteriano/genética , Ácido Diaminopimélico/metabolismo , Ácidos Graxos/análise , Genoma Bacteriano/genética , Lipídeos de Membrana/análise , Filogenia , RNA Ribossômico 16S/genética
8.
Drug Dev Ind Pharm ; 43(7): 1143-1153, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28277848

RESUMO

This study was oriented toward the disintegration profiling of the diclofenac sodium (DS) immediate-release (IR) tablets and development of its relationship with medium permeability kperm based on Kozeny-Carman equation. Batches (L1-L9) of DS IR tablets with different porosities and specific surface area were prepared at different compression forces and evaluated for porosity, in vitro dissolution and particle-size analysis of the disintegrated mass. The kperm was calculated from porosities and specific surface area, and disintegration profiles were predicted from the dissolution profiles of IR tablets by stripping/residual method. The disintegration profiles were subjected to exponential regression to find out the respective disintegration equations and rate constants kd. Batches L1 and L2 showed the fastest disintegration rates as evident from their bi-exponential equations while the rest of the batches L3-L9 exhibited the first order or mono-exponential disintegration kinetics. The 95% confidence interval (CI95%) revealed significant differences between kd values of different batches except L4 and L6. Similar results were also spotted for dissolution profiles of IR tablets by similarity (f2) test. The final relationship between kd and kperm was found to be hyperbolic, signifying the initial effect of kperm on the disintegration rate. The results showed that disintegration profiling is possible because a relationship exists between kd and kperm. The later being relatable with porosity and specific surface area can be determined by nondestructive tests.


Assuntos
Excipientes/química , Permeabilidade , Comprimidos , Química Farmacêutica , Cinética , Porosidade , Solubilidade
9.
Int J Syst Evol Microbiol ; 66(12): 5444-5451, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27707430

RESUMO

A Gram-stain-negative, rod-shaped bacterium, forming yellow colonies and designated CDR SL 15T, was isolated from the surface of Padina sp., a brown macroalga, which grows in the Western coastal regions of the state of Goa, India. The 16S rRNA gene sequence phylogeny placed the strain in the genus Luteimonas and it showed closest sequence similarity to Luteimonas terricola BZ92rT (97.6 %) and <97.0 % to other species of the genus Luteimonas. Chemotaxonomic features, such as having iso-C15 : 0 and summed feature 9 (C16 : 0 10-methyl/iso-C17 : 1ω9c) as the major fatty acids and Q-8 as the only ubiquinone further supported its placement within this genus. There were some critical differences in phenotypic properties between Luteimonas padinae sp. nov. CDR SL 15T and L. terricola DSM 22344T i.e. temperature range for growth and salinity range and optimum for growth (L. terricola is a psychrotolerant bacterium with a lower optimum temperature for growth), acid production and assimilation of substrates, enzyme activities and resistance to certain antibiotics. The DNA-DNA relatedness value of the novel strain with its closest phylogenetic relative was only 40 %, below the 70 % threshold value recommended for species delineation. All these characteristics are consistent with strain CDR SL 15T representing a novel species of the genus Luteimonas, for which the name Luteimonas padinae sp. nov. is proposed. The type strain is CDR SL 15T (=DSM 101536T=KCTC 52403T).


Assuntos
Filogenia , Alga Marinha/microbiologia , Xanthomonadaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Índia , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química , Xanthomonadaceae/genética , Xanthomonadaceae/isolamento & purificação
10.
J Food Sci Technol ; 53(7): 3093-3103, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27765980

RESUMO

Phenolic content, antioxidant activities and antimicrobial activities of methanolic, ethanolic and ethyl acetate extracts of five different varieties of aonla (Emblica officinalis) fruits as well their powders were evaluated. Total polyphenolic content in fresh aonla fruit extracts varied from 70.6 to 159.4 mg GAE/g and their EC 50 (effective concentration) values for antioxidant activity ranged from 46.72 to 359.7 µg/ml. Significant varietal difference were observed in antioxidant activity of the extracts of fresh aonla fruit and powder. Among the variety analyzed, Desi variety exhibited significantly higher TPC (total polyphenol content) and antioxidant activity in fresh as well as dried form in all the extracts. Methanolic extracts of various varieties had maximum TPC and antioxidant activity. Variety NA-7 showed high TPC and antioxidant activity. Almost, similar trend was observed among the extracts of aonla powders for TPC and AOA (antioxidant activity). A high positive correlation coefficient existed between TPC and AOA of different aonla extracts. All the extracts analyzed, exhibited a strong antimicrobial potential against E. coli, Salmonella typhi, Staphylococcus aureus and Candida albicans. This study suggests aonla as potential natural source of antioxidants and antimicrobial agents.

11.
Curr Pharm Des ; 22(19): 2761-87, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26898740

RESUMO

Development of effective drug delivery systems is important for medicine and healthcare. Polymer particulates (micro- and nanoparticles) have opened new opportunities in the field of drug delivery by overcoming various limitations of conventional delivery methods. The properties of polymeric particles can be readily tuned by precisely engineering the constituent blocks of polymers for improving drug loading, release rate, pharmacokinetics, targeting, etc. The end-groups of various polymers can be readily modified with ligands making them suitable for recognizing by cell-specific receptors, providing cellular specificity, and superior intracellular delivery. This review will mainly cover delivery of many potential drugs and biomolecules by means of polymeric microparticles, nanoparticles and copolymer micelles or assemblies. An overview about formulation methods of polymer particulates has also been addressed. Attempt has been made to cover all the potential polymers that are well known in pharmaceutical history.


Assuntos
Sistemas de Liberação de Medicamentos , Polímeros/química , Humanos , Micelas
12.
J Int Soc Prev Community Dent ; 5(Suppl 2): S129-32, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26942117

RESUMO

AIM: The aim of this study is to compare the oral hygiene status among institutionalized visually impaired children of age between 6 and 20 years given with Braille and audio instructions in Raichur city of Karnataka. MATERIALS AND METHODS: A total of 50 children aged between 6 to 20 years were included in this study from a residential school for visually impaired children. These children were randomly divided into two equal groups. One group was given oral hygiene instructions by audio recordings and another written in Braille and were instructed to practice the same. After three months time the oral hygiene status and dental caries experience was recorded and compared using patient performance index. Statistical analysis was done by student paired t test and multiple comparison by Tukey's HSD (honest significant difference) test. RESULTS: The mean PHP (Patient Hygiene Performance) score of group A at baseline was 3.88 compared to 3.90 of group B. At 7 days PHP score of group A and group B was 3.42 and 3.45 respectively. At 3 month PHP score of group A and group B was 2.47 and 2.86 respectively. Even though over a period of time the mean score of PHP index reduced the score comparison between the 2 groups were statistically non significant. In group A the mean difference of PHP score between baseline and 7 days was 0.46, between baseline and 3 months it was 1.40. The PHP score between 7 days and 3 months was 0.94. All the above values were statistically significant. CONCLUSION: Effective dental health education method has to be instituted for visually impaired children. The present study shows improvement of oral health status in both the study population by decrease in the mean plaque score. Hence continuous motivation and reinforcement in the form of Braille and audio instruction is beneficial to achieve good oral hygiene levels in visually impaired children.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...