Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 6 de 6
Filter
Add more filters










Database
Language
Publication year range
1.
Microb Pathog ; 152: 104611, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33212199

ABSTRACT

The present study aims to establish pathogenic variability among Colletotrichum truncatum, an incitant of anthracnose disease across different chilli growing regions of Karnataka. Thirty suspected C. truncatum isolates were identified based on their morphological and conidial characteristics and further confirmed by Internal Transcribed Spacer DNA sequence analysis. Pathogenicity test was carried out by in vitro detached leaf and fruit assay, and also under greenhouse conditions using 20 different chilli cultivars grown across Karnataka. Colletotrichum truncatum isolates recorded the varied degree of pathogenicity index (PI) on different chilli cultivars. Isolate UOM-02 was found highly virulent (PI > 80 against 12 tested cultivars) and cultivar cv. 4 was found highly resistant to C. truncatum infection (Average PI, 48.21). Further, the involvement of enzymes such as cellulase, pectin methylesterase and ascorbate peroxidase in determining the virulence of the pathogen was established. The highest activity of catalase (UOM-24; 7.38 units), ascorbate peroxidase (UOM-02; 2.9 units), cellulase (UOM-02; 0.58 units), and pectin methylesterase (UOM-02; 6.7 units), was recorded by different C. truncatum isolates. Cellulase and pectin methylesterase activities were positively correlated with their pathogenicity, while catalase activity was found least correlated. Results of RAPD and ISSR analysis recorded higher polymorphism among the isolates. Interestingly these isolates were not clustered based on their geographical origin, Pathogenicity index and biochemical characters. From this study, the existence of highly virulent C. truncatum isolate (UOM-02), which can cause severe loss under favourable conditions, was revealed. Further, possible use of specific enzymes as an indicator of virulence of the pathogen is discussed.


Subject(s)
Capsicum , Colletotrichum , Capsicum/genetics , Colletotrichum/genetics , India , Plant Diseases , Random Amplified Polymorphic DNA Technique
2.
J Food Sci Technol ; 55(10): 4356-4362, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30228435

ABSTRACT

Enzymatic browning is a major factor affecting the quality of sugarcane juice, mainly due to the activities of polyphenol oxidase (PPO) and peroxidase (POD). Effect of bentonite (0-1%, w/v) on the activities of these enzymes, when employed alone and also in combination with acidulants, was determined. Bentonite alone could reduce the activities of PPO and POD enzymes to 160 and 24.2 u/mL, respectively. The PPO and POD activity was completely inhibited below pH 4.1 when ascorbic acid was used alone or in combination with bentonite. However, PPO and POD activity was inhibited to 60 and 51 u/mL, respectively, at pH 3.7 when citric acid was used individually and to 112 and 15.36 u/mL, respectively, when employed along with bentonite. In addition, color changes at 4 and 10 °C were measured during the storage of sugarcane juice.

3.
J Biosci ; 42(4): 603-611, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29229878

ABSTRACT

In continuation of our studies on the bioaccessibility of phenolic compounds from food grains as influenced by domestic processing, we examined the uptake of phenolics from native/sprouted finger millet (Eleucine coracana) and green gram (Vigna radiata) and native/heat-processed onion (Allium cepa) in human Caco-2 cells. Absorption of pure phenolic compounds, as well as the uptake of phenolic compounds from finger millet, green gram, and onion, was investigated in Caco-2 monolayer model. Transport of individual phenolic compounds from apical compartment to the basolateral compartment across Caco-2 monolayer was also investigated. Sprouting enhanced the uptake of syringic acid from both these grains. Open-pan boiling reduced the uptake of quercetin from the onion. Among pure phenolic compounds, syringic acid was maximally absorbed, while the flavonoid isovitexin was least absorbed. Apparent permeability coefficient P(app) of phenolic compounds from their standard solutions was 2.02 x 10-6cm/s to 8.94 x 10-6cm/s. Sprouting of grains enhanced the uptake of syringic acid by the Caco-2 cells. Open-pan boiling drastically reduced the uptake of quercetin from the onion. The permeability of phenolic acids across Caco-2 monolayer was higher than those of flavonoids.


Subject(s)
Apigenin/metabolism , Flavonoids/metabolism , Gallic Acid/analogs & derivatives , Phenols/metabolism , Quercetin/metabolism , Apigenin/isolation & purification , Biological Transport , Caco-2 Cells , Eleusine/chemistry , Flavonoids/isolation & purification , Gallic Acid/isolation & purification , Gallic Acid/metabolism , Humans , Kinetics , Onions/chemistry , Phenols/isolation & purification , Quercetin/isolation & purification , Vigna/chemistry
4.
J Sci Food Agric ; 97(2): 621-628, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27122477

ABSTRACT

BACKGROUND: Polyphenols in food are valued for their health-beneficial influences. Food acidulants lime juice and amchur used in Indian cookery were evaluated for their influence on polyphenol bioaccessibility from food grains. RESULTS: Lime juice increased bioaccessible flavonoids by 25% in roasted finger millet, while there was no change in total bioaccessible polyphenols in pressure-cooked, open-pan-boiled and roasted finger millet in the presence of food acidulants. Addition of amchur to pressure-cooked and microwave-heated pearl millet increased bioaccessible flavonoids by 30 and 53% respectively, while lime juice increased them by 46% in pressure-cooked pearl millet. Increased bioaccessibility of specific phenolic acids from finger millet and pearl millet was observed upon addition of these food acidulants. The presence of either lime juice or amchur increased bioaccessible flavonoids from both legumes studied. Addition of lime juice and amchur, however, exerted a negative effect on the bioaccessibility of several phenolic compounds from food grains in native state and under certain processing conditions. CONCLUSION: Thus food acidulants lime juice and amchur had a significant influence on the bioaccessibility of health-beneficial phenolic compounds from food grains. Use of food acidulants in food preparations could be a strategy to enhance the bioavailability of polyphenols, especially flavonoids from grains. © 2016 Society of Chemical Industry.


Subject(s)
Cooking/methods , Digestion , Edible Grain/chemistry , Fabaceae/chemistry , Flavoring Agents/chemistry , Models, Biological , Polyphenols/metabolism , Antioxidants/analysis , Antioxidants/metabolism , Citrus aurantiifolia/chemistry , Diet/adverse effects , Diet/ethnology , Edible Grain/growth & development , Fabaceae/growth & development , Flavonoids/analysis , Flavonoids/metabolism , Flavoring Agents/adverse effects , Fruit/adverse effects , Fruit/chemistry , Fruit and Vegetable Juices/adverse effects , Fruit and Vegetable Juices/analysis , Germination , Humans , Hydrogen-Ion Concentration , India , Mangifera/chemistry , Nutritive Value , Polyphenols/analysis , Seeds/chemistry , Seeds/growth & development , Spices/adverse effects , Spices/analysis
5.
J Agric Food Chem ; 62(46): 11170-9, 2014 Nov 19.
Article in English | MEDLINE | ID: mdl-25340251

ABSTRACT

Cereals (wheat and sorghum) and legumes (green gram and chickpea) commonly consumed in Asia and Africa were evaluated for polyphenolic content. Bioaccessibility of polyphenols from these grains as influenced by domestic processing was also estimated. Total polyphenol content of wheat and sorghum was 1.20 and 1.12 mg/g respectively, which was increased by 49% and 20% respectively, on roasting. In contrast, a significant reduction of the same was observed in both the cereals after pressure-cooking, open-pan boiling, and microwave heating. Total flavonoids, which was 0.89 mg/g in native sorghum, reduced drastically after processing. Tannin content of both the cereals significantly increased on sprouting as well as roasting. Total polyphenol content reduced by 31% on sprouting but increased to 24% on roasting in green gram. Pressure-cooking (53%), open-pan boiling (64%), and microwave heating (>2-fold increase) significantly increased total polyphenol content in chickpea, while drastic reduction was observed in the total flavonoid content. Bioaccessible total polyphenols from these grains were in the following order: green gram > chickpea > wheat > sorghum. Domestic processing of these grains had minimal/no effect on the bioaccessible total flavonoid content. Not all the phenolic compounds present in them were bioaccessible. Concentration of bioaccessible phenolic compounds increased especially on sprouting and roasting of these grains, except chickpea, where sprouting significantly reduced the same (476 to 264 µg/g). Microwave heating significantly enhanced the concentration of bioaccessible polyphenols especially from chickpea. Thus, sprouting and roasting provided more bioaccessible polyphenols from the cereals and legumes studied.


Subject(s)
Cicer/chemistry , Cooking/methods , Fabaceae/chemistry , Polyphenols/chemistry , Sorghum/chemistry , Triticum/chemistry , Microwaves
6.
Food Chem ; 164: 55-62, 2014 Dec 01.
Article in English | MEDLINE | ID: mdl-24996305

ABSTRACT

Finger millet (Eleusine coracana) and pearl millet (Pennisetum glaucum) were evaluated for polyphenolic content and their bioaccessibility. Total polyphenols of native finger millet was 10.2mg/g which reduced by 50% after sprouting or pressure-cooking, while 12-19% reduction was seen after open-pan boiling. Total flavonoids of the grain reduced drastically on sprouting, pressure-cooking or open-pan boiling. Concentration of phenolic acids generally increased during sprouting and roasting of finger millet. Pressure cooking, open-pan boiling and microwave-heating reduced the bioaccessible polyphenols by 30-35%, while the same was increased by 67% by sprouting. Significant reduction of total polyphenols was observed in pressure-cooked, open-pan boiled and microwave-heated pearl millet. Concentration of sinapic and salicylic acids were highest phenolic acids of pearl millet. Total polyphenols reduced during sprouting and pressure-cooking. There was a 20% increase in the bioaccessible polyphenols after sprouting of pearl millet. Thus, sprouting and roasting provided more bioaccessible phenolics from these two common millets studied.


Subject(s)
Eleusine/chemistry , Pennisetum/chemistry , Polyphenols/analysis , Biological Availability , Chromatography, High Pressure Liquid , Cooking , Edible Grain/chemistry , Flavonoids/analysis , Tannins/analysis
SELECTION OF CITATIONS
SEARCH DETAIL
...