Their high bioactive compounds content and importance as dietary antioxidants has increased interest in Capsicum fruit. The fruit of seven Capsicum chinense Jacq. var. habanero genotypes grown in Yucatan, Mexico, were...Their high bioactive compounds content and importance as dietary antioxidants has increased interest in Capsicum fruit. The fruit of seven Capsicum chinense Jacq. var. habanero genotypes grown in Yucatan, Mexico, were analyzed to quantify their phenolic compounds, carotenoids and ascorbic acid contents, and to measure their free radical scavenging (ABTS assay) and antioxidant activities (β-carotene/linoleic acid assay). Phenolics (20.54 to 20.75 mg/100 g sample), carotenoids (1.00 to 1.26 mg/100 g sample) and ascorbic acid contents (187.24 to 281.73 mg/100 g sample) varied between genotypes. Trolox equivalent antioxidant capacity (TEAC) ranged from 1.55 to 3.23 mM/mg sample. During the 120-min decolorization trial, antioxidant capacity decreased over time in the studied genotypes. Values ranged from 36%to 57% β-carotene bleaching during the first 30 minutes. Fruit from all seven studied genotypes are good antioxidant sources and hold promise as natural ingredients in functional foods.展开更多
Sodium alginate is a polysaccharide that is largely obtained from the brown algae （Sargassum sp.）.It has been used as a wonderful growth promoting substance in its depolymerized form for various plants.The aim of th...Sodium alginate is a polysaccharide that is largely obtained from the brown algae （Sargassum sp.）.It has been used as a wonderful growth promoting substance in its depolymerized form for various plants.The aim of this study was to find out the effects of various concentrations of γ-irradiated sodium alginate （ISA）,viz.,deionized water （control,T0）,20 （T1）,40 （T2）,60 （T3）,80 （T4）,and 100 ppm （T5） on the agricultural performance of Catharanthus roseus L.（Rosea） in terms of growth attributes,photosynthesis,physiological activities,and alkaloid production.The present work revealed that ISA applied as leaf-sprays at concentrations from 20 to 100 ppm might improve growth,photosynthesis,physiological activities,and alkaloid production in C.roseus L.significantly.Of the various ISA concentrations,80 ppm proved to be the best one compared to other concentrations applied.展开更多
The ratio of leaf carotenoid to chlorophyll(Car/Chl)is an indicator of vegetation photosynthesis,development and responses to stress.However,the correlation between Car and Chl,and their overlapping absorption in the ...The ratio of leaf carotenoid to chlorophyll(Car/Chl)is an indicator of vegetation photosynthesis,development and responses to stress.However,the correlation between Car and Chl,and their overlapping absorption in the visible spectral domain pose a challenge for optical remote sensing of their ratio.This study aims to investigate combinations of vegetation indices(VIs)to minimize the influence of Car-Chl correlation,thus being more sensitive to the variability in the ratio across vegetation species and sites.VIs sensitive to Car and Chl variability were combined into four candidates of combinations,using a simulated dataset from the PROSPECT model.The VI combinations were then tested using six simulated datasets with different Car-Chl correlations,and evaluated against four independent datasets.The ratio of the carotenoid triangle ratio index(CTRI)with the red-edge chlorophyll index(CIred-edge)was found least influenced by the Car-Chl correlation and demonstrated a superior ability for estimating Car/Chl variability.Compared with published VIs and two machine learning algorithms,CTRI/CIred-edge also showed the optimal performance in the fourfield datasets.This new VI combination could be useful to provide insights in spatiotemporal variability in the leaf Car/Chl ratio,applicable for assessing vegetation physiology,phenology,and response to environmental stress.展开更多
基金This research was supported by the Fundación PRO-DUCE AC-Yucatán,México(Project“Determinación de las propiedades funcionales del chile habanero”).
文摘Their high bioactive compounds content and importance as dietary antioxidants has increased interest in Capsicum fruit. The fruit of seven Capsicum chinense Jacq. var. habanero genotypes grown in Yucatan, Mexico, were analyzed to quantify their phenolic compounds, carotenoids and ascorbic acid contents, and to measure their free radical scavenging (ABTS assay) and antioxidant activities (β-carotene/linoleic acid assay). Phenolics (20.54 to 20.75 mg/100 g sample), carotenoids (1.00 to 1.26 mg/100 g sample) and ascorbic acid contents (187.24 to 281.73 mg/100 g sample) varied between genotypes. Trolox equivalent antioxidant capacity (TEAC) ranged from 1.55 to 3.23 mM/mg sample. During the 120-min decolorization trial, antioxidant capacity decreased over time in the studied genotypes. Values ranged from 36%to 57% β-carotene bleaching during the first 30 minutes. Fruit from all seven studied genotypes are good antioxidant sources and hold promise as natural ingredients in functional foods.
文摘Sodium alginate is a polysaccharide that is largely obtained from the brown algae （Sargassum sp.）.It has been used as a wonderful growth promoting substance in its depolymerized form for various plants.The aim of this study was to find out the effects of various concentrations of γ-irradiated sodium alginate （ISA）,viz.,deionized water （control,T0）,20 （T1）,40 （T2）,60 （T3）,80 （T4）,and 100 ppm （T5） on the agricultural performance of Catharanthus roseus L.（Rosea） in terms of growth attributes,photosynthesis,physiological activities,and alkaloid production.The present work revealed that ISA applied as leaf-sprays at concentrations from 20 to 100 ppm might improve growth,photosynthesis,physiological activities,and alkaloid production in C.roseus L.significantly.Of the various ISA concentrations,80 ppm proved to be the best one compared to other concentrations applied.
基金supported by the National Natural Science Foundation of China(42001314)the Open Research Fund of the State Laboratory of Information Engineering in Surveying,Mapping,and Remote Sensing,Wuhan University(grant number 20R02)+1 种基金Torbern Tagesson was additionally funded by the Swedish National Space Agency(SNSA 2021-00144)FORMAS(Dnr.2021-00644).
文摘The ratio of leaf carotenoid to chlorophyll(Car/Chl)is an indicator of vegetation photosynthesis,development and responses to stress.However,the correlation between Car and Chl,and their overlapping absorption in the visible spectral domain pose a challenge for optical remote sensing of their ratio.This study aims to investigate combinations of vegetation indices(VIs)to minimize the influence of Car-Chl correlation,thus being more sensitive to the variability in the ratio across vegetation species and sites.VIs sensitive to Car and Chl variability were combined into four candidates of combinations,using a simulated dataset from the PROSPECT model.The VI combinations were then tested using six simulated datasets with different Car-Chl correlations,and evaluated against four independent datasets.The ratio of the carotenoid triangle ratio index(CTRI)with the red-edge chlorophyll index(CIred-edge)was found least influenced by the Car-Chl correlation and demonstrated a superior ability for estimating Car/Chl variability.Compared with published VIs and two machine learning algorithms,CTRI/CIred-edge also showed the optimal performance in the fourfield datasets.This new VI combination could be useful to provide insights in spatiotemporal variability in the leaf Car/Chl ratio,applicable for assessing vegetation physiology,phenology,and response to environmental stress.
