scholarly journals Aflatoxin species: their health effects and determination methods in different foodstuffs

2012 ◽  
Vol 10 (3) ◽  
pp. 675-685 ◽  
Author(s):  
Sezgin Bakırdere ◽  
Selin Bora ◽  
E. Bakırdere ◽  
Fırat Aydın ◽  
Yasin Arslan ◽  
...  

AbstractCarcinogenic and mutagenic properties of aflatoxin species are known in literature. Their intake over a long time period might be health-dangerous for human even at trace levels. It is well known that different foodstuffs can be contaminated by aflatoxin species through growing and storage. Due to the serious health effects, sensitive determination of aflatoxin species in any matrices related with the human being is very crucial at trace levels. In literature, there are sensitive techniques to analyze the different samples for the contents of their aflatoxin species. Each technique has some advantages and disadvantages over the other techniques. This review aims to summarize the different health effects of aflatoxin species, development of analytical techniques and applications of developed techniques in a variety of matrices.

Table II : Quantitative determination of carbonyl compounds at different odour sources (concentrations in ppb) Rendering plant Gelatine plant neighbourhood neighbourhood Formaldehyde 40 16 Acetaldehyde 39 24 Acetone 36 73 Prcpanal 10 -Isobutyraldehyde 10 30 Pentanal 15 19 Hexanal 3.52 Heptanal 12.5 Octanal 10.5 Nonanal 1 2 acids (figure 7). However extractions always involve a serious decrease in sensitivity, while evaporation of the extract produces a solution in 0.1-0.5 ml of solvent, and only 1 pi of it can be brought in the gas chromatograph. Therefore work is in progress to enhance sensitivity by converting acids in­ to halogenated derivatives, which can be GC-analysed with the more sensitive electron-capture detector. For thiols a similar procedure is investigated as with aldehydes. One possibility is absorption of thiols in an alkaline solution and reaction with 2,4-dinitrochlorobenzene, yielding 2,4-dinitrofenylsulfides, which are analysed by HPLC (9). Sane improvements on removal of reagents at the one hand and on separation of sane by-products on the other hand have to be achieved in order to in­ crease the sensitivity with another factor of ten. 5. CONCLUSION The actual scope and limitations of chemical analysis of odour show that all problems can be tackled as far as emission is concerned. For iititiission measurements seme progress is necessary, but there is no essential reason why chemical analysis would be unable to attain the desired sensitivity for all types of odorants. There is no doubt that in a few years the last dif­ ficulties will be solved. In order to achieve real control of odour nui­ sance, automatic measurement is necessary on a long time basis. There again seme technical development is to be expected. Does this mean that machines are going to decide if an odour is pre­ sent or not? By no means, while the population will always be the reference, and psychophysical measurements will be necessary to make chemical analysis possible.


2020 ◽  
Vol 8 (2) ◽  
pp. 383
Author(s):  
Mukhaila Iryani ◽  
Yusnita Yusnita ◽  
Dwi Hapsoro ◽  
Kukuh Setiawan ◽  
Agus Karyanto

Hybrid moth orchid (genus Phalaenopsis) is one of the most popular ornamentals in Indonesia. It has beautiful and long-lasting flowers, but cultivating this orchid is still become a challenging issues due to the need of specific condition to grow and long time period to re-blooming. Plant growth regulators (PGR) (i.e. Benzyladenine (BA)) has been widely documented as a flower-inducing substance in several orchids. However, the optimal concentration and its mechanism in inducing flower-stalk bud and re-blooming is still unclear. This research aimed to study the effects of BA application in the form of lanolin paste on hybrid Phalaenopsis flower-stalk buds. We conducted this study using completely randomized design with four replications at the greenhouse laboratory Faculty of Agriculture University of Lampung on August to December 2018. We divided the orchid into 5 group of BA concentration (0, 1000, 1500, 3000, or 6000 ppm). The sheath of the fourth or fifth buds of the flowers were carefully opened, then it smeared with BA. The percentage of bud break into flower spike or keiki, length of shoots or spike and number of open flowers were recorded until 10 weeks of observation. The results showed that, neither of the buds under the control treatment (without BA), 1000 ppm nor 1500 ppm BA broke and grew into keiki or spike. On the other hand, application of BA at 3000 ppm or 6000 ppm successfully induced 100% flower spikes on the buds treated. No keiki was formed in all buds treated. In addition, treatment of the buds with 6000 ppm BA produced longer flower spikes as well as more open flowers. We conclude that the application of BA (minimal 3000 ppm) successfully induced flower spike of  hybrid Phalaenopsis.


Author(s):  
Aleksey Michailovich Chaulin ◽  
Duplyakov V Dmitry

Cardiovascular diseases have a leading role in terms of morbidity, mortality, and disability of the population, causing significant socio-economic damage to all countries of the world. This circumstance requires researchers to constantly seek for new biomarkers and improve methods for determining existing biomarkers, and search for new therapeutic targets to improve diagnostic and treatment strategies. Recently, there have been some important changes in laboratory diagnostics of patients with acute coronary syndrome, due to the introduction into the routine practice of new high and ultrasensitive methods for the determination of biomarkers of injury, specific to cardiac muscle tissue, namely cardiac troponins. A key advantage of highly sensitive immunochemical assays is the ability to detect cardiac troponins in the early stages of myocardial infarction. This allows making the optimal decision on the early choice and conduct of reperfusion therapy, which significantly improves the further prognosis of patients. Among the most significant generally recognised disadvantages of highly sensitive determination methods are low specificity and a huge variety of troponin immunoassays. The decrease in specificity is reflected in the fact that cardiac troponins are no longer considered the “gold standard” of diagnosis related to Acute Myocardial Infarction (AMI) (irreversible ischaemic damage to cardiomyocytes). As a result, any damage to the myocardium, even insignificant and reversible under physiological state (physical activity, stress) and several pathological conditions, can lead to an increase in serum levels of cardiac troponins and affect the accuracy of the diagnosis. Each method for the determination of cardiac troponins, among the existing wide variety of troponin immunoassays, possesses different analytical characteristics, and detects different concentrations of troponins in the same patient. This article provides a view of current data on the biology of cardiac troponins, and defines the analytical characteristics of new high-sensitive methods for the determination of cardiac troponins.


1988 ◽  
Vol 34 (8) ◽  
pp. 1540-1544 ◽  
Author(s):  
J Costello ◽  
D M Landwehr

Abstract The methods used for determination of oxalate in blood are reviewed, and the advantages and disadvantages of the two basic approaches--direct methods and in vivo isotope-dilution techniques--are compared. Possible reasons for the previous discrepancies between direct and isotopic methods are discussed, as are the effects of protein binding, sample handling, and storage conditions on oxalate values in plasma. Necessary precautions for obtaining reproducible results are presented. We recommend and critically review several direct methods, and describe the application of a direct method for oxalate determination in some other biological fluids.


2001 ◽  
Vol 73 (6) ◽  
pp. 933-958 ◽  
Author(s):  
Ole Hertel ◽  
Frank A. A. M. De Leeuw ◽  
Steen Solvang Jensen ◽  
David Gee ◽  
Olf Herbarth ◽  
...  

_Human exposure to outdoor air pollution is believed to cause severe health effects, especially in urban areas where pollution levels often are high, because of the poor dispersion conditions and high density of pollution sources. Many factors influence human health, and a good assessment of human air pollution exposure is, therefore, crucial for a proper determination of possible links between air pollution and health effects. Assessment of human exposure is, however, not straightforward, and this is the background for the present paper, which recommends how to carry out such assessments. Assessment of human exposure to air pollution may be carried out by use of:categorical classification, application of biomarkers, analysis of air pollution data from routine monitoring networks, personal portable exposure monitors, or application of mathematical air pollution exposure models. The categorical classification is a crude indirect method based on indicators of exposure such as type of residence, type of job, presence of indoor sources, etc. Categorical classification is generally inadequate for application in air pollution epidemiology. Biomarkers can be a strong instrument in assessment of health effects and provide information about air pollution exposure and dose. Use of biomarkers is, therefore, particularly useful when applied in combination with exposure assessment through one of the methods 3 to 5. The main focus of this paper is on these three methods for determination of human air pollution exposure. The optimal solution is clearly a combination of methods 2 to 5, but the available resources often set a limit to how far the assessment is carried out, and the choice of strategy will, therefore, often be very important for the outcome of the final study. This paper describes how these approaches may be applied and outlines advantages and disadvantages of the approaches used individually and in combination. Furthermore, some examples of specific applications in Denmark and the Netherlands are given for illustration.


2018 ◽  
Vol 18 ◽  
pp. 428-434
Author(s):  
N. A. Matsak ◽  
S. A. Kirilenko ◽  
O. O. Posashkov

The article outlines the mandatory quality requirements for manufactured and installed metal entrance shockproof doors, which should ensure the safety of life, health and property of citizens. The main technical features of these designs and their characteristics are presented. The problem of quality control is considered, since quality is a guarantee of reliability and a guarantee that doors will serve for a long time and reliably. The installation of high-quality "armored" doors will not only protect housing from unauthorized penetration, but also help to isolate the premise from the external environment; therefore in the problem of selecting entrance metal doors, an important place is occupied by the issue of heat and sound insulation. While choosing a good metal door, every detail should be taken into account. The quality of the goods and safety of the premise directly depend on all design components. The article raises such a topical issue as the establishment of quality works on manufacture, storage, transportation and mounting of entrance metal shockproof doors while performing forensic construction and technical examination. The technical characteristics of building materials that can be used in this case are presented. The authors also pointed out that it is very important to resolve disputes on this type of researches, so this is the availability of technical documentation. All data about the product should be included in this documentation up to the information on transportation and storage, since this information will much facilitate the work of experts in the future. After all, the establishment of the quality of this type of products is a fairly complex and time-consuming process. While determining the quality, all details are important, starting from the quality of the used building materials, the works on manufacturing of the door blocks, their storage and transportation conditions, and finishing the placing (mounting).


Author(s):  

Engineers in the field of hydrology often face the task of determining the hydrological characteristics for river gauges not covered by a regular network of hydrometric observations. This task is usually solved using classical methods and approaches, as described in SP 33-101-2003 «Determination of Basic Hydrological Characteristics», and is highly time-consuming, both in terms of search and acquisition of hydrological data and the time-consuming computational procedure. At the same time, modern progress in hydrological modeling allows us to look at the solution to this problem from a different angle. Thus, in this paper we propose to reduce the problem of determining the characteristics of river runoff in the absence of observation data to a simpler problem of determining the characteristics of river runoff in the presence of observation data. For this purpose, we propose to use regional gridded reanalysis of river runoff R5 as a source of model-based runoff approximation in the river gauges of interest. The results of the performed calculations show high potential of the proposed approach for determining the characteristics of river runoff. Thus, for the studied Upper Volga river basins the deviations of the calculated values from the reference data of the State Hydrological Institute are negligeable. R5 runoff reanalysis was developed using freely distributed software and open data sources – GR4J conceptual hydrological model and WFDEI meteorological reanalysis. The R5 database covers both a large geographical domain within the European territory of Russia and a long time period (1979–2016) and is freely available at: https://zenodo.org/record/2600695.


1980 ◽  
Vol 53 (4) ◽  
pp. 849-902 ◽  
Author(s):  
R. A. Ridha

Abstract The pneumatic tire is often taken for granted as a simple and reliable component of the vehicle. A closer look, however, shows that the tire in service is subjected to severe stresses and deformations whose quantities must be determined in order to accurately predict tire performance. Modern tire structures have evolved through a series of modifications of the original pneumatic rubber tire. These modifications were based on field experiences and on mostly experimental studies of tire behavior. The use of analytical techniques to calculate tire stresses and deformations remained limited in scope for a long time because the complexity of the tire structure placed it beyond the domain of available methods of analysis. The recent emphasis on analytical techniques is due, at least partly, to their potential for becoming less time consuming and less expensive than experimental methods, the need for predicting a tire's behavior before its manufacture, and the notable advances in computational and structural analysis methods. In this paper, these methods are described and applied to the calculation of tire stresses and deformations. Structural analysis is the analytical determination of structural responses to a prescribed set of applied loads. The responses may be displacements or distortions if force loads are known, or forces if displacement or distortions are known. Given the geometry of a structure (shape, dimensions), the relevant properties of its component materials, the magnitude and distribution of applied loads, and any constraints from boundary conditions, then structural analysis is used to calculate displacements, strains, or stresses at any chosen location in or on the structure. These calculated values may be compared to those required for functionality of the structure. Although structural analysis is not directly applicable to determining the most efficient configuration of the structural components, the analysis of successive well chosen modifications can often optimize compositions or geometries. The application of structural analysis to a tire requires (a) knowledge of the relevant physical properties of the component materials, and their configuration in the tire, (b) complete characterization of the applied loads, and (c) an analytical technique (i.e. theory) for calculating the required responses. These requirements are explained in the following sections.


1984 ◽  
Vol 30 (10) ◽  
pp. 1625-1630
Author(s):  
F P Peters ◽  
J C Hafkenscheid

Abstract Kits of five different suppliers, composed according to the Dutch recommendations for determination of the enzyme activity of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, gamma-glutamyltransferase, alkaline phosphatase, and creatine kinase, were intercompared. Activity concentrations of the enzymes in human sera were measured under defined conditions, evaluated, and related to the actual composition of the kits. Concentrations of all kit components were determined by various analytical techniques. The overall results of the activity measurements and the composition of at least three kits inter-agree well. We found deviations as great as 10% in our analytical evaluation of the kits of the other two suppliers, which can partly be accounted for.


Author(s):  
SATYA PRASAD B ◽  
JAYAKUMARI S

A review is presented on different analytical techniques used for quantitative analysis of selected anticoagulants dabigatran, rivaroxaban, and prasugrel. Efforts have been made to collate all the relevant references to the extent possible. The review discusses the advantages and disadvantages of the cited analytical techniques, which will help to give insights into the methods used for estimation of selected anticoagulants such as dabigatran, rivaroxaban, and prasugrel, from clinical isolates, and its dosage forms. The review highlights the basic as well as advanced techniques performed for estimating dabigatran, rivaroxaban, and prasugrel. The techniques illustrated here have been demonstrated to be useful for quantitative determination of selected anticoagulants and may find application in analyzing other related properties.


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