Gallic acid and hydrolysable tannins are formed in birch leaves from an intermediate compound of the shikimate pathway

Ossipov, Vladimir; Salminen, Juha‐Pekka; Ossipova, Svetlana; Haukioja, Erkki; Pihlaja, Kalevi

doi:10.1016/s0305-1978(02)00081-9

Cited by 118 publications

(95 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Typically, gallic acid is produced from shikimic acid by the shiminate pathway. 29) We assumed that gallic acid is mainly produced by hydrolysis of galloyl ester of tannic acid, ECG, EGCG, GCG, chlorogenic acid, theaflavin-3-gallate, and so on in this study.…”

Section: Resultsmentioning

confidence: 99%

Analysis of Green Tea Compounds and Their Stability in Dentifrices of Different pH Levels

Jang

Park

Ahn

et al. 2014

CHEMICAL & PHARMACEUTICAL BULLETIN

View full text Add to dashboard Cite

In this study, green tea compounds (flavonoids, alkaloids, and phenolic acids) were analyzed in green tea-containing dentifrices, and their stability at different pH levels was evaluated. The compounds were separated under 0.01% phosphoric acid-acetonitrile gradient conditions and detected by photodiode array detector at 210, 280, 300, 335 nm. Column temperature was set at 20°C based on the results of screening various temperatures. Each compound showed good linearity at optimized wavelength as well as showing good precision and accuracy in dentifrices. Using this method, the stability of compounds was investigated in pH 4, 7, 8, and 10 solutions for 96 h, and in pH 7 and pH 10 solutions for 6 months. The green tea compounds were more stable at low pH levels; purine alkaloids were more stable than flavonoids. In particular, gallocatechin (GC), epigallocatechin (EGC), epigallocatechin gallate (EGCG), gallocatechin gallate (GCG), and myricetin almost disappeared in pH 10 solutions after 96 h. In dentifrices, the compounds were gradually decreased until 6 months in both pH types, while gallic acid was increased because of production of galloyl ester of other green tea compounds. Therefore, it is beneficial to adjust to as low a pH as possible when produce green teacontaining dentifrices.

show abstract

Section: Resultsmentioning

confidence: 99%

Analysis of Green Tea Compounds and Their Stability in Dentifrices of Different pH Levels

Jang

Park

Ahn

et al. 2014

CHEMICAL & PHARMACEUTICAL BULLETIN

View full text Add to dashboard Cite

show abstract

“…At the same time, Fig. 4.10 shows that ET concentration varies a lot between individual birch trees, as evidenced by the relatively large standard-deviation bars (Salminen et al, 2001Ossipov et al, 2003). It is fully possible that two white birches growing side by side might have over 50-fold differences in their foliar concentrations of monomeric ETs.…”

Section: Distributions Of Different Types Of Tannin In Plantsmentioning

confidence: 94%

“…It is fully possible that two white birches growing side by side might have over 50-fold differences in their foliar concentrations of monomeric ETs. In fact, it appears that species like white birch which synthesize monomeric HHDP esters but no oligomer have a higher within-species variation in their ET content than do species that accumulate oligomeric ETs (Salminen et al, 2001(Salminen et al, , 2004Ossipov et al, 2003;Salminen, unpublished data from Geum, Fragaria, Rubus, Epilobium, Potentilla, and Alchemilla species). Another apparent difference in these types of species (ET monomers versus ET oligomers) is that individual galloyl glucoses tend to accumulate in the ET monomer-specific species but not in the ET oligomer-specific species.…”

Section: Distributions Of Different Types Of Tannin In Plantsmentioning

confidence: 99%

The Chemistry and Chemical Ecology of Ellagitannins in Plant–Insect Interactions: From Underestimated Molecules to Bioactive Plant Constituents

Salminen

2014

Recent Advances in Polyphenol Research

Self Cite

View full text Add to dashboard Cite

This chapter reviews our current knowledge of the chemistry and chemical ecology of ellagitannins (ETs), placing particular emphasis on the role these under-appreciated polyphenols play in plant-herbivore interactions. Instead of the traditional tannin-linked activity that comes from their complex formation with proteins, it discusses tannins' less well-known pro-oxidant activity. ETs are likely the most active tannin pro-oxidants. Plant cells synthesize ETs via the shikimate pathway, utilizing the enzymatic conversion of dehydroshikimic acid into gallic acid and further to galloyl glucoses. During the biosynthetic steps from monogalloyl glucose towards pentagalloyl glucose, the pro-oxidant activity of the polyphenols decreases, but it begins to increase again as soon as pentagalloyl glucose is transformed to glucopyranose-based ETs and further to very active C-glycosidic ETs. Thus, the tannin-based pro-oxidant capacity of a plant cell is highly dependent on the total and relative concentrations of different types of products or intermediates of the hydrolyzable tannin pathway. Within plant species that accumulate different types of galloyl glucoses and ETs differing in pro-oxidant activities, this balance typically varies significantly. The situation is further complicated by the variation in ETs observed seasonally and between individual plants. In addition, ETs may also derive their antiherbivore activities via their hydrolysis products, which is largely an unexplored area of research. Historically, ETs have not been taken specifically into account as plant-defense compounds, mainly due to difficulties in their compound-specific analysis from the plant cell. Recent developments in tannin chemistry have diminished these problems and the joint effort of ecologists and

show abstract

“…Because tannins are complex and energetically costly molecules to synthesize, their widespread occurrence and abundance suggests that tannins play an important role in plant function and evolution (Zucker 1983). Tannins occur in plant leaves, roots, wood, bark, fruits and buds (Peters & Constabel, 2002;Ossipov et al, 2003). Tannin distribution in plant tissues appears to vary from species to species.…”

Section: Chemistry and Occurrence Of Tanninsmentioning

confidence: 99%

Quantitative Chemical Defense Traits, Litter Decomposition and Forest Ecosystem Functioning

Rahman¹,

Motiur²

2012

Forest Ecosystems - More Than Just Trees

View full text Add to dashboard Cite

Gallic acid and hydrolysable tannins are formed in birch leaves from an intermediate compound of the shikimate pathway

Cited by 118 publications

References 25 publications

Analysis of Green Tea Compounds and Their Stability in Dentifrices of Different pH Levels

Analysis of Green Tea Compounds and Their Stability in Dentifrices of Different pH Levels

The Chemistry and Chemical Ecology of Ellagitannins in Plant–Insect Interactions: From Underestimated Molecules to Bioactive Plant Constituents

Quantitative Chemical Defense Traits, Litter Decomposition and Forest Ecosystem Functioning

Contact Info

Product

Resources

About