Fructooligosaccharides changes during maturation in inflorescences and seeds of onion (Allium cepa L. ‘W202’)

Abstract

Shiomi, N., Benkeblia, N., Onodera, S. and Kawazoe, N. 2006. Fructooligosaccharides changes during maturation in inflorescences and seeds of onion (Allium cepa L. 'W202'). Can. J. Plant Sci. 86: 269-278. The distribution of fructooligosaccharides (FOS) and their related enzyme activities during the development of the inflorescences and the maturation of seeds in onion (Allium cepa L.) were investigated. Concentrations of glucose, fructose and sucrose in three inflorescence parts -complete floral parts (FP), pedicels (PD) and involucres (IV) -increased steadily during the first 8 wk of sampling and then decreased over for the next 6 wk. However the final glucose, fructose and sucrose contents were not significantly higher than those observed at the beginning of sampling. Surprisingly, FOS concentration in the inflorescence parts for the saccharides studied showed similar patterns with concentrations increasing during the first 6 wk and decreasing during the last 6 wk of the study. On the other hand, FL and PD parts contained higher amounts of FOS than IV parts. The activities of sucrose:sucrose 1-fructosyltransferase (SST), fructan:fructan 6 G -fructosyltransferase (6G-FFT) and fructan:fructan 1 F -fructosyltransferase (1-FFT) showed similar patterns in seeds, decreasing slowly during the first weeks and remaining stable thereafter. The ratio 6G-FFT to 1-FFT decreased after 9 wk from 2.40 to 1.44 with an average of 2.1. In contrast, activities of invertase and β-fructofuranosidase increased progressively, although β-fructofuranosidase activity was twice as high as invertase activity during the last 2 wk. The ratio of synthesizing to hydrolysing activities decreased progressively to 0.2 and was below the value 1 after 9 wk. Thus, it seems that seed maturation was reached during the last week of August, which is 2 to 3 wk earlier than seed harvest normally occurs in Hokkaido.Key words: Fructooligosaccharides, flower organs, seeds, onion Shiomi, N., Benkeblia, N., Onodera, S. et Kawazoe, N. 2006. Fructooligosaccharides changes during maturation in inflorescences and seeds of onion (Allium cepa L. 'W202'). Can. J. Plant Sci. 86: 269-278. Notre étude a porté sur la variation de la teneur en fructooligosaccharides (FOS) et l'activité de leurs enzymes durant le développement des inflorescences et la maturation des graines chez l'oignon (Allium cepa L.). Les concentrations du glucose, du fructose et du saccharose dans les trois parties des ombelles -parties florales (PF) ; pédicelles (PD) et involucres (IV) -augmentèrent légèrement durant les huit premières semaines de l'échantillonnage puis diminuèrent durant les six semaines suivantes. Cependant, les teneurs finales en glucose, fructose et saccharose n'étaient pas significativement plus élevées que celles observées au début de l'échantillonnage. Les teneurs en FOS des différents organes des ombelles pour les saccharides étudiés montrèrent des profils similaires avec des concentrations augmentant durant les six premières semaines et diminuant durant les six dernières de...

Comparison of the water-soluble carbohydrate composition and fructan structures of Agave tequilana plants of different ages

“…1, it can be inferred that at 2 years, the synthesis of fructans was beginning and the accumulation of fructans as reserve carbohydrate was in the initial phase. The increase of sugar accumulated as fructans has been observed also in physiological process of multiple plants, like the seeds maturation process of onion (Allium cepa L. ''W202"), during re-growth and flower development of Galanthus nivalis bulbs and during maturation process of Cichorium intybus L. and Helianthus tuberosus L. (Monti et al, 2005;Orthen & Wehrmeyer, 2004;Saengthongpinit & Sajjaanantakul, 2005;Shiomi et al, 2005;Wilson et al, 2004). The common characteristic of the accumulation processes in these plants is that normally the accumulated fructans are linear with b(2?1) linkages whereas in A. tequilana and other graminans like Urginea maritima they are highly branched (Spies et al, 1992).…”

“…Avila-Fernandez et al (2007) have found that in A. tequilana plants, the enzyme 1-SST showed an estimated kcat value of 260 min À1 , corresponding to a lower turnover number than the value of kcat observed for 1-SST from H. tuberosus (1566 min À1 ). This could explain why in A. tequilana plants the accumulation of sugars is slower with longer times for harvest (8-12 years) than other typical fructan producing plants ( AvilaFernandez et al, 2009;Cedeño, 1995;Monti et al, 2005;Orthen & Wehrmeyer, 2004;Saengthongpinit & Sajjaanantakul, 2005;Shiomi et al, 2005;Wilson et al, 2004). In Fig.…”

“…Thus our results are in agreement with this previous behaviour observed. The polymerisation and depolymerisation of fructans is a phenomena observed in most of the fructan accumulating plants and is associated in most of the cases to regulation of water imbalances, adaptation to cold weather or to accumulation of reserve carbohydrate and post utilisation as an energy source for flowering or re-growth (Dias-Tagliacozzo et al, 2004;Monti et al, 2005;Orthen & Wehrmeyer, 2004;Saengthongpinit & Sajjaanantakul, 2005;Shiomi et al, 2005;Tolsma, Read, & Tolhurst, 2007;Vijn & Smeekens, 1999;Wilson et al, 2004). Therefore, probably the behaviour observed of fructans distribution of A. tequilana plants from 2 to 6½ was due to a fructan accumulation process, which is a required step for agave plants before flowering.…”

“…The comparison of fructan linkage analysis between A. tequilana, Agave potatorum, Agave cantala, Agave fourcroydes and Agave angustifolia showed differences in the proportions of glucose polymerised, as well as in the proportions of b(2?6) and b(2?1) linkages of the principal chains (Mancilla-Margalli & Lopez, 2006). In addition, for other plants different to Agavaceae family, the synthesis of fructans is influenced by the production region, the soil nutrients, the plant variety, the seasonal changes, the water regime and the harvest time (Dias-Tagliacozzo, Itaya, Machado de Carvalho, Figueiredo-Ribeiro, & Dietrich, 2004;Faustini-Cuzzuol, MachadoCarvalho, Penteado-Zaidan, & Roberto-Furlani, 2005;Livingstone, Premakumar, & Tallury, 2006;Martínez-Noël, Tognetti, Nagaraj, Wiemken, & Pontis, 2006;Monti, Amaducci, Pritoni, & Venturi, 2005;Morcuende, Kostadinova, Pérez, & Martínez-Carrasco, 2005;Orthen & Wehrmeyer, 2004;Saengthongpinit & Sajjaanantakul, 2005;Shiomi, Benkeblia, Onodera, & Kawazoe, 2005;Wilson, Smith, & Yonts, 2004). To our knowledge, there is only one report about the influence on A. tequilana age over the tequila fermentation process (Pinal et al, 2009).…”

Food Biochemical Study on Fructans and Related Synthesis Enzymes

“…35) 3. Post-harvest metabolism of fructo-oligosaccharides in onion and asparagus plants Alongside the studies on fructo oligodsaccharide accumulation during seed development 36) and bulbing, 37) we also studied the main enzyme activities involved in the synthesis and the hydrolysis of fructo oligosaccharides during the pre harvest 38) (growth), and post harvest 38,39) (storage) life of onion bulbs and asparagus spears, 40) although present knowledge is insufficient to clearly explain the mechanisms triggering enzymes or the mechanisms by which fructo oligosaccharides contribute to bulb quality and perishability. 39) Storage of onion bulbs for 6 months causes a decrease 41,42) in the contents of glucose, fructose and sucrose, as shown by Fig.…”