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Comparison of methods for determining the content and polymerization of proanthocyanidins and catechins

100%

Oszmianski J., Bourzeix M.

Polish Journal of Food and Nutrition Sciences

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1996

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tom 05

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nr 2

The methods with vanillin (V), Folin-Ciocalteau (FC) or dimethyla- minocinnamaldehyde (DC) reagent and spectometric method at 280 nm (A) for determining the content of proanthocyanidins and catechins and their polymerization degree were compared. The (+) catechin, (-)epicatechin and their dimer and trimer standards, and grape wine, wine concentrate and powdered wine were examined. The DC reagent appeared most sensitive in the catechin and proanthocyanidin analysis with the molar absorption values for catechins being 55-fold higher than for the FC reagent In the proanthocyanidin analysis with the DC reagent the use of catechin standard curve is not recommended for the determination of proanthocyanidin content because the concentrations of 0.5 g/L for dimers and 0.3 g/L for trimers were obtained instead of 1 g/L in model solutions. Hie V/DC value approximated most closely the real values of proanthocyanidin polymerization.

2

Investigation of acrylamide formation in vanillin-asparagine model system

84%

Hamzahoglu A., Gokmen V.

Polish Journal of Food and Nutrition Sciences

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2011

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tom 61

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nr Suppl.1

3

Widma absorpcyjne produktow reakcji waniliny z taninami z nasion roslin straczkowych

84%

Karamac M., Amarowicz R.

Bromatologia i Chemia Toksykologiczna

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2002

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tom 35

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nr 3

297-299

4

Allelopathic activity of dehulled rice and its allelochemicals on weed germination

84%

Khang D. T., Anh L. H., Thu Ha P. T., Tuyen P. T., Quan N. V., Minh L. T., Quan N. T., Minh T. N., Xuan T. D., Khanh T. D., Trung K. H.

International Letters of Natural Sciences

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2016

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tom 58

In this study, the allelopathic potential of dehulled rice, rice, and hulls of rice on germination of weeds was evaluated in laboratory. Phenolic acids in growth media of these plants were also identified and quantified using HPLC. Identified allelochemicals were reversely tested for phytotoxic effects on germination and seedling growth of barnyardgrass, lettuce, radish and rice. The results showed that the inhibitory effects of dehulled rice were stronger than those of hulls and rice. Dehulled rice caused 66.7% and 50.6% reduction in radish root length and lettuce shoot height, respectively. Dehulled rice showed strong inhibitory effects on root length of lettuce and shoot height of radish while hulls and rice exhibited stimulation. Regarding phenolic identification, vanillin and vanillic acid were detected as allelochemicals in root exudates of rice and tested plants. The results revealed that most of the vanillin and vanillic acid treatments showed high inhibitory effects on germination rates and seedling growth of lettuce and radish, high stimulatory activity on root elongation of rice. Vanillic acid (100 ppm and 200 ppm), vanillin (100 ppm) and their mixture (200 ppm) completely inhibited survival of lettuce. The findings indicate the allelopathic potential of dehulled rice which can be used for identification of more phytotoxins to produce bioherbicides in agricultural practices.

5

HPLC and ESI-MS analysis of vanillin analogue 2-hydroxy-4-methoxy benzaldehydein swallow root - the influence of habitat heterogeneity on antioxidant potential

67%

Pradeep M., Shetty N. P., Giridhar P.

Acta Scientiarum Polonorum. Hortorum Cultus

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2019

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tom 18

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nr 2

Decalepis hamiltonii Wight & Arn., is a plant species that is endemic to southern parts of India. The aim of this study is to explore the influence of habitat heterogeneity on total phenolics, flavonoids, flavor compound 2-hydroxy-4-methoxy benzaldehyde (2H4MB) and antioxidant potential of tubers. The flavor metabolite 2H4MB was quantified by HPLC using isocratic solvent system (methanol : acetonitrile : water : acetic acid 47 : 10 : 42 : 1) that indicates obvious difference in 2H4MB content of tubers with a maximum of 96.4 ±2.6 and 92.6 ±1.2 mg 100 g–1 dry weight basis (DW) in samples from B.R. Hills and Mysore area of Karnataka, followed by samples from Tirumalai Hills and Kurnool from Andhra Pradesh (89.02 ±0.9 mg 100 g–1 DW), Tamil Nadu (81.6 ±2.4 mg 100 g–1 DW) and Kerala (80.18 ±1.1 mg 100 g–1 DW) of tubers. There was variation in total phenolics, total flavonoids and 2H4MB content of root samples collected from different habitats. Also significant variation in free radical scavenging potential of methanol root extracts was noticed, which is directly proportional to the phenolics, and flavonoids content. Overall, there was 10–16% difference in content of 2H4MB in D. hamiltonii tubers that were collected from different natural habitats, and this habitat heterogeneity has to be considered vital, while using such tubers for edible purposes and food formulations.

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The connection between chosen phenolic compounds occurring in wood and the range of trophic abilities of birch bracket (Piptoporus betulinus (Bull.) P. Karst.)

67%

Zarzynski P., Andres B.

Folia Forestalia Polonica. Series B - Drzewnictwo

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2010

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tom 41

7

Badanie czystości waniliny polskiej metodą chromatografii bibułowej

67%

Zyszczynska-Florian B., Andrelowicz A.

Roczniki Państwowego Zakładu Higieny

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1962

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tom 13

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nr 6

8

Perspektywy zastosowania biotechnologii w produkcji lotnych zwiazkow smakowo-zapachowych

67%

Pleszczynska M.

Żywność Nauka Technologia Jakość

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2001

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tom 08

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nr 1

14-24

Praca prezentuje obecny stan badań nad mikrobiologiczną produkcją naturalnych związków smakowo-zapachowych, zwłaszcza laktonów, związków aromatycznych (waniliny i aldehydu benzoesowego) oraz terpenów. Szczególny nacisk położono na przedstawienie zalet, ograniczeń oraz perspektyw wykorzystania w tym celu procesów biotransformacji.

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