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Žaneta Ugarčić-hardi - One of the best experts on this subject based on the ideXlab platform.
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Spectrofluorimetric, spectrophotometric and chemometric analysis of wheat grains infested by Sitophilus granarius
Journal of Stored Products Research, 2012Co-Authors: Ivica Strelec, Lucija Kučko, Dragica Roknić, Vladimir Mrša, Žaneta Ugarčić-hardiAbstract:Abstract Invisible infestation of wheat grains by Sitophilus granarius during postharvest handling is one of the main problems particularly for small enterprises and farm grain storage facilities due to the lack of cheap and fast methods for early detection of infestation, especially when only a small proportion of grain is infested by larvae. In order to determine whether the spectrofluorimetric, spectrophotometric or chemometric analysis of various extracts of wheat grains infested by S. granarius larvae could be used for detection of infested grain, four different types of extracts: 50 mmol dm −3 Tris–HCl pH 8.9, aqueous iso -propanol ( φ = 0.55), methanol, and aqueous trichloroacetic acid ( γ = 0.2 mg cm −3 ), of non-infested and infested wheat grains have been examined for fluorescence properties and UV/VIS spectral characteristics, while the chemometric analysis included determination of protein, reactive amino groups, polyphenols and soluble sugar content. Analysis of extracts revealed significant differences in UV/VIS spectral characteristics, level of reactive amino groups and polyphenol content between infested and non-infested grains. The results obtained indicate that instrumental analysis of spectral characteristics of grain extracts could be used as a method for determination of grain infestation.
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Spectrofluorimetric, spectrophotometric and chemometric analysis of wheat seeds infested by Sitophilus granarius
2011Co-Authors: Ivica Strelec, Lucija Kučko, Dragica Roknić, Vladimir Mrša, Žaneta Ugarčić-hardiAbstract:Invisible infestation of wheat seeds by Sitophilus granarius during field ripening or postharvest handling is one of the main problems for grain storage facilities due to the lack of cheap and fast method of infestation detection, especially when small amount of seeds is infected by larvae. In order to determine whether the spectrofluorimetric, spectrophotometric and chemometric analysis of various extracts of wheat seeds infested by Sitophilus granarius larvae could be used for detection of seeds infestation, four different types of extracts: 50 mM Tris-HCl pH 8.9 ; 55% iso-propanol, methanol, and 20% TCA, of non-infested and infested wheat seeds have been examined for fluorescence properties and UV/VIS spectral characteristics, while chemometric analysis included determination of protein, reactive amino group, soluble sugar and polyphenolic content. Analysis of extracts of non-infested and moderately or significantly infested wheat seeds revealed significant differences in UV/VIS spectral characteristics and level of reactive amino groups and polyphenols between infested and non-infested seeds. Obtained results indicate that instrumental analysis of spectral characteristics of seed extracts could be used as a method for determination of seed infestation.
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Biochemical indicators of wheat seeds infestation by Sitophilus granarius
2008Co-Authors: Ivica Strelec, Vladimir Mrša, Žaneta Ugarčić-hardiAbstract:Sitophilus granarius is one of the most destructive pests of stored wheat grains. Immature stages of this insect develops inside kernels causing weight and nutritional loss, fungal growth and subsequent mycotoxins accumulation leading to impracticability of using infested grains in food and feed production. Although Croatian and EU Regulative prohibits the use of infested grains in food production, production of infestation-contaminated cereal products cannot be avoided since detection of the internal grain infestation could be easily misinterpreted due to imperfection of the most worldwide methods used, basically relying on visual detection and counting. Since advanced methods for detection of internal grain infestation, such as X-ray analysis and computer tomography are quite expensive, there is a need for the development of alternative methods of detection, among which biochemical analysis could be valuable tool. The objective of this research was to examine whether the oxidoreductive or proteolytic enzyme activities and differences in electrophoretic protein pattern can be used for detection of internal wheat seed infestation by Sitophilus granarius. Infested and non-infested wheat seed samples, and Sitophilus granarius adults were examined for activities of glutathione reductase (GR), catalase (CAT), guaiacol peroxidase (POX), polyphenol oxidase (PPO), lipooxygenase (LOX), aminopeptidases preferentially splitting N-terminal amino acids of arginine and phenylalanine (Arg-AP, Phe-AP), carboxypeptidase II (CP-II) and aspartic protease, as well as for differences in protein pattern of sequentially extracted proteins (50 mM Tris-HCl buffer pH 8.0 ; 55 % (w/v) 2-propanol containing 0.5 % (w/v) DTT ; 3 M urea containing 1 % (v/v) Nonidet NP-40 and 0.5 % (w/v) DTT) separated by Native PAGE, SDSPAGE and IEF with pH 3.5-9.5 gradient. Enzyme activity differences between non-infested and infested wheat seeds indicate that CPII (91 % activity decrease), CAT (172 % activity increase), and PPO (146 % activity increase) could be used as potential indicators of wheat seed infestation by Sitophilus granarius. Electrophoretic analysis revealed SDS-PAGE of proteins extracted with (a) 50 mM Tris-HCl buffer pH 8.0, or (b) 2-propanol containing 0.5 % (w/v) DTT, and IEF with pH 3.5-9.5 gradient of proteins extracted with 2-propanol containing 0.5 % (w/v) DTT as potential electrophoretic methods for detection of internal wheat seed infestation.
Ivica Strelec - One of the best experts on this subject based on the ideXlab platform.
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Spectrofluorimetric, spectrophotometric and chemometric analysis of wheat grains infested by Sitophilus granarius
Journal of Stored Products Research, 2012Co-Authors: Ivica Strelec, Lucija Kučko, Dragica Roknić, Vladimir Mrša, Žaneta Ugarčić-hardiAbstract:Abstract Invisible infestation of wheat grains by Sitophilus granarius during postharvest handling is one of the main problems particularly for small enterprises and farm grain storage facilities due to the lack of cheap and fast methods for early detection of infestation, especially when only a small proportion of grain is infested by larvae. In order to determine whether the spectrofluorimetric, spectrophotometric or chemometric analysis of various extracts of wheat grains infested by S. granarius larvae could be used for detection of infested grain, four different types of extracts: 50 mmol dm −3 Tris–HCl pH 8.9, aqueous iso -propanol ( φ = 0.55), methanol, and aqueous trichloroacetic acid ( γ = 0.2 mg cm −3 ), of non-infested and infested wheat grains have been examined for fluorescence properties and UV/VIS spectral characteristics, while the chemometric analysis included determination of protein, reactive amino groups, polyphenols and soluble sugar content. Analysis of extracts revealed significant differences in UV/VIS spectral characteristics, level of reactive amino groups and polyphenol content between infested and non-infested grains. The results obtained indicate that instrumental analysis of spectral characteristics of grain extracts could be used as a method for determination of grain infestation.
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Spectrofluorimetric, spectrophotometric and chemometric analysis of wheat seeds infested by Sitophilus granarius
2011Co-Authors: Ivica Strelec, Lucija Kučko, Dragica Roknić, Vladimir Mrša, Žaneta Ugarčić-hardiAbstract:Invisible infestation of wheat seeds by Sitophilus granarius during field ripening or postharvest handling is one of the main problems for grain storage facilities due to the lack of cheap and fast method of infestation detection, especially when small amount of seeds is infected by larvae. In order to determine whether the spectrofluorimetric, spectrophotometric and chemometric analysis of various extracts of wheat seeds infested by Sitophilus granarius larvae could be used for detection of seeds infestation, four different types of extracts: 50 mM Tris-HCl pH 8.9 ; 55% iso-propanol, methanol, and 20% TCA, of non-infested and infested wheat seeds have been examined for fluorescence properties and UV/VIS spectral characteristics, while chemometric analysis included determination of protein, reactive amino group, soluble sugar and polyphenolic content. Analysis of extracts of non-infested and moderately or significantly infested wheat seeds revealed significant differences in UV/VIS spectral characteristics and level of reactive amino groups and polyphenols between infested and non-infested seeds. Obtained results indicate that instrumental analysis of spectral characteristics of seed extracts could be used as a method for determination of seed infestation.
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Biochemical indicators of wheat seeds infestation by Sitophilus granarius
2008Co-Authors: Ivica Strelec, Vladimir Mrša, Žaneta Ugarčić-hardiAbstract:Sitophilus granarius is one of the most destructive pests of stored wheat grains. Immature stages of this insect develops inside kernels causing weight and nutritional loss, fungal growth and subsequent mycotoxins accumulation leading to impracticability of using infested grains in food and feed production. Although Croatian and EU Regulative prohibits the use of infested grains in food production, production of infestation-contaminated cereal products cannot be avoided since detection of the internal grain infestation could be easily misinterpreted due to imperfection of the most worldwide methods used, basically relying on visual detection and counting. Since advanced methods for detection of internal grain infestation, such as X-ray analysis and computer tomography are quite expensive, there is a need for the development of alternative methods of detection, among which biochemical analysis could be valuable tool. The objective of this research was to examine whether the oxidoreductive or proteolytic enzyme activities and differences in electrophoretic protein pattern can be used for detection of internal wheat seed infestation by Sitophilus granarius. Infested and non-infested wheat seed samples, and Sitophilus granarius adults were examined for activities of glutathione reductase (GR), catalase (CAT), guaiacol peroxidase (POX), polyphenol oxidase (PPO), lipooxygenase (LOX), aminopeptidases preferentially splitting N-terminal amino acids of arginine and phenylalanine (Arg-AP, Phe-AP), carboxypeptidase II (CP-II) and aspartic protease, as well as for differences in protein pattern of sequentially extracted proteins (50 mM Tris-HCl buffer pH 8.0 ; 55 % (w/v) 2-propanol containing 0.5 % (w/v) DTT ; 3 M urea containing 1 % (v/v) Nonidet NP-40 and 0.5 % (w/v) DTT) separated by Native PAGE, SDSPAGE and IEF with pH 3.5-9.5 gradient. Enzyme activity differences between non-infested and infested wheat seeds indicate that CPII (91 % activity decrease), CAT (172 % activity increase), and PPO (146 % activity increase) could be used as potential indicators of wheat seed infestation by Sitophilus granarius. Electrophoretic analysis revealed SDS-PAGE of proteins extracted with (a) 50 mM Tris-HCl buffer pH 8.0, or (b) 2-propanol containing 0.5 % (w/v) DTT, and IEF with pH 3.5-9.5 gradient of proteins extracted with 2-propanol containing 0.5 % (w/v) DTT as potential electrophoretic methods for detection of internal wheat seed infestation.
Kenji Mori - One of the best experts on this subject based on the ideXlab platform.
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Grain weevil,Sitophilus granarius (L.): Antennal and behavioral responses to male-produced volatiles
Journal of Chemical Ecology, 1996Co-Authors: John Chambers, Peter R. White, Carolyn M. Gerrard, Kenji MoriAbstract:Coupled GC-EAG techniques have been applied to the study of volatiles from the grain weevil, Sitophilus granarius . for the first time. The size of EAG response was independent of the sex of the responding insect but was consistently larger to extracts of males than those of females. This difference was reflected in a behavioral preference for the male extracts by mated adults of both sexes tested together and virgin adults of both sexes tested separately. The GC-EAG results provide evidence for two materials that are released specifically by the males. Using circular dichroism. one has been found to be identical stereochemically with the (2 S ,3 R )-sitophilate reported by others as the aggregation pheromone in a different strain. This enhances the prospects for the development of a single pheromone lure that would be generally applicable whatever the origin of the strain. The small amount of sitophilate found in the males suggests that it is not stored in large amounts. The other material, present in such a small amount that it has yet to be fully characterized, elicits a higher antennal activity than sitophilate and may have a significant role to play in enhancing the trap catch of this economically important pest.
Rudy Plarre - One of the best experts on this subject based on the ideXlab platform.
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an attempt to reconstruct the natural and cultural history of the granary weevil Sitophilus granarius coleoptera curculionidae
European Journal of Endocrinology, 2010Co-Authors: Rudy PlarreAbstract:It is generally accepted that stored grain insects are food opportunists and, when originally made the transition to man-made storage facilities, came from natural reservoirs like bird or rodent nests. This may not be true for Sitophilus granarius. Among all stored-product insects, the granary weevil S. granarius is the only species never recorded outside of storage facilities. Anatomical, physiological, and behavioural aspects of recent and hypothetical ancestral species in the genus Sitophilus are presented and discussed in terms of adaptation to the anthropogenic storage of grain. Full development inside the host kernel, endosymbioses with bacteria, and the reduction in flight activity to prevent water loss in a dry environment can be regarded as pre-adaptations for the evolution of a full synanthropic grain pest of cosmopolitan distribution. Faunistic, archaeological, and historical evidences of the pest's origin and spread in conjunction with early agriculture are reviewed to support a hypothesis of a co-evolutionary event with the dawn of Neolithic agriculture.
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Three-dimensional distribution of Sitophilus granarius (L.) (Coleoptera: Curculionidae) in wheat influenced by the synthetic aggregation pheromone
Journal of Stored Products Research, 1996Co-Authors: Rudy PlarreAbstract:The distribution pattern of Sitophilus granarius released in different weevil densities in a large bulk of ca. 350 kg wheat was investigated using a three-dimensional trapping grid of surface and bottom pitfall-traps, as well as probe-traps beneath the surface at eight different trap locations. Baiting the surface, bottom and pitfall traps of a single trapping location each with ca. 6000 ng of the synthetic aggregation pheromone sitophilate considerably changed the distribution of the weevils. In the presence of the pheromone, the overall catch of all trap sites combined was reduced at lower weevil densities. The insects tended to stay in the interkernel space beneath the surface. The aggregation pheromone acted more as an arrestant than an attractant chemical. The sex specific effects and the behavior modifying character of sitophilate in the granary weevil is discussed in relation to practical application, which may lead to an improvement of monitoring systems in the field of stored product protection.
Vladimir Mrša - One of the best experts on this subject based on the ideXlab platform.
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Spectrofluorimetric, spectrophotometric and chemometric analysis of wheat grains infested by Sitophilus granarius
Journal of Stored Products Research, 2012Co-Authors: Ivica Strelec, Lucija Kučko, Dragica Roknić, Vladimir Mrša, Žaneta Ugarčić-hardiAbstract:Abstract Invisible infestation of wheat grains by Sitophilus granarius during postharvest handling is one of the main problems particularly for small enterprises and farm grain storage facilities due to the lack of cheap and fast methods for early detection of infestation, especially when only a small proportion of grain is infested by larvae. In order to determine whether the spectrofluorimetric, spectrophotometric or chemometric analysis of various extracts of wheat grains infested by S. granarius larvae could be used for detection of infested grain, four different types of extracts: 50 mmol dm −3 Tris–HCl pH 8.9, aqueous iso -propanol ( φ = 0.55), methanol, and aqueous trichloroacetic acid ( γ = 0.2 mg cm −3 ), of non-infested and infested wheat grains have been examined for fluorescence properties and UV/VIS spectral characteristics, while the chemometric analysis included determination of protein, reactive amino groups, polyphenols and soluble sugar content. Analysis of extracts revealed significant differences in UV/VIS spectral characteristics, level of reactive amino groups and polyphenol content between infested and non-infested grains. The results obtained indicate that instrumental analysis of spectral characteristics of grain extracts could be used as a method for determination of grain infestation.
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Spectrofluorimetric, spectrophotometric and chemometric analysis of wheat seeds infested by Sitophilus granarius
2011Co-Authors: Ivica Strelec, Lucija Kučko, Dragica Roknić, Vladimir Mrša, Žaneta Ugarčić-hardiAbstract:Invisible infestation of wheat seeds by Sitophilus granarius during field ripening or postharvest handling is one of the main problems for grain storage facilities due to the lack of cheap and fast method of infestation detection, especially when small amount of seeds is infected by larvae. In order to determine whether the spectrofluorimetric, spectrophotometric and chemometric analysis of various extracts of wheat seeds infested by Sitophilus granarius larvae could be used for detection of seeds infestation, four different types of extracts: 50 mM Tris-HCl pH 8.9 ; 55% iso-propanol, methanol, and 20% TCA, of non-infested and infested wheat seeds have been examined for fluorescence properties and UV/VIS spectral characteristics, while chemometric analysis included determination of protein, reactive amino group, soluble sugar and polyphenolic content. Analysis of extracts of non-infested and moderately or significantly infested wheat seeds revealed significant differences in UV/VIS spectral characteristics and level of reactive amino groups and polyphenols between infested and non-infested seeds. Obtained results indicate that instrumental analysis of spectral characteristics of seed extracts could be used as a method for determination of seed infestation.
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Biochemical indicators of wheat seeds infestation by Sitophilus granarius
2008Co-Authors: Ivica Strelec, Vladimir Mrša, Žaneta Ugarčić-hardiAbstract:Sitophilus granarius is one of the most destructive pests of stored wheat grains. Immature stages of this insect develops inside kernels causing weight and nutritional loss, fungal growth and subsequent mycotoxins accumulation leading to impracticability of using infested grains in food and feed production. Although Croatian and EU Regulative prohibits the use of infested grains in food production, production of infestation-contaminated cereal products cannot be avoided since detection of the internal grain infestation could be easily misinterpreted due to imperfection of the most worldwide methods used, basically relying on visual detection and counting. Since advanced methods for detection of internal grain infestation, such as X-ray analysis and computer tomography are quite expensive, there is a need for the development of alternative methods of detection, among which biochemical analysis could be valuable tool. The objective of this research was to examine whether the oxidoreductive or proteolytic enzyme activities and differences in electrophoretic protein pattern can be used for detection of internal wheat seed infestation by Sitophilus granarius. Infested and non-infested wheat seed samples, and Sitophilus granarius adults were examined for activities of glutathione reductase (GR), catalase (CAT), guaiacol peroxidase (POX), polyphenol oxidase (PPO), lipooxygenase (LOX), aminopeptidases preferentially splitting N-terminal amino acids of arginine and phenylalanine (Arg-AP, Phe-AP), carboxypeptidase II (CP-II) and aspartic protease, as well as for differences in protein pattern of sequentially extracted proteins (50 mM Tris-HCl buffer pH 8.0 ; 55 % (w/v) 2-propanol containing 0.5 % (w/v) DTT ; 3 M urea containing 1 % (v/v) Nonidet NP-40 and 0.5 % (w/v) DTT) separated by Native PAGE, SDSPAGE and IEF with pH 3.5-9.5 gradient. Enzyme activity differences between non-infested and infested wheat seeds indicate that CPII (91 % activity decrease), CAT (172 % activity increase), and PPO (146 % activity increase) could be used as potential indicators of wheat seed infestation by Sitophilus granarius. Electrophoretic analysis revealed SDS-PAGE of proteins extracted with (a) 50 mM Tris-HCl buffer pH 8.0, or (b) 2-propanol containing 0.5 % (w/v) DTT, and IEF with pH 3.5-9.5 gradient of proteins extracted with 2-propanol containing 0.5 % (w/v) DTT as potential electrophoretic methods for detection of internal wheat seed infestation.