Fructans and other water soluble carbohydrates in vegetative organs and fruits of different Musa spp. accessions

Abstract

The water soluble carbohydrates (WSC) glucose, fructose, and sucrose are well-known to the great public, but fructans represent another type of WSC that deserves more attention given their prebiotic and immunomodulatory properties in the food context. Although the occurrence of inulin-type fructo-oligosaccharides (FOS) was proposed in the fruit of some banana accessions, little or no information is available neither on the exact identity of the fructan species, nor on the fructan content in different parts of banana plants and among a broader array of banana cultivars. Here, we investigated the WSC composition in leaves, pulp of ripe fruits and rhizomes from mature banana plants of 11 accessions (I to XI), including both cultivated varieties and wild Musa species. High performance anion exchange chromatography with integrated pulsed amperometric detection (HPAEC-IPAD) showed the presence of 1-kestotriose [GF2], inulobiose [F2], inulotriose [F3], 6-kestotriose and 6G-kestotriose (neokestose) fructan species in the pulp of mature fruits of different accessions, but the absence of 1,1-nystose and 1,1,1 kestopentaose and higher degree of polymerization (DP) inulin-type fructans. This fructan fingerprint points at the presence of one or more invertases that are able to use fructose and sucrose as alternative acceptor substrates. Quantification of glucose, fructose, sucrose and 1-kestotriose and principal component analysis (PCA) identified related banana groups, based on their specific WSC profiles. These data provide new insights in the biochemical diversity of wild and cultivated bananas, and shed light on potential roles that fructans may fulfill across species, during plant development and adaptation to changing environments. Furthermore, the promiscuous behavior of banana fruit invertases (sucrose and fructose as acceptor substrates besides water) provides a new avenue to boost future work on structure-function relationships on these enzymes, potentially leading to the development of genuine banana fructosyltransferases that are able to increase fructan content in banana fruits.

Extraction optimization and profile analysis of oligosaccharides in banana pulp and peel

“…Until the current data, the following oligosaccharides were identified in the banana pulp: 1‐kestose (1‐kestotriose, GF 2 ), 1,1‐nystose (GF 3 ), 1 F ‐β‐fructofuranosyl‐nystose (GF 4 ) (Campbell et al, ; Der Agopian et al, ), 6‐kestotriose, 6 G ‐kestotriose (older name, neokestose), bifurcose (1,6‐kestotetraose), inulobiose (F 2 ), and inulotriose (F 3 ) (Cruz‐Cárdenas et al, ; Der Agopian et al, ). In our study, the chromatographic analysis showed the presence of 1‐kestose, xylopentaose and xylohexaose, whereas the last two compounds were identified for the first time in the banana pulp.…”

“…Banana is a good source of minerals, carbohydrates and fiber such as pectin and resistant starch (Der Agopian, Purgatto, Cordenunsi, & Lajolo, ; Englyst & Cummings, ; Mitsou et al, ). Recent studies also showed that banana has remarkable amounts of oligosaccharides, especially fructans type FOS (fructooligosaccharides) and short‐chain inulins, such as 1‐kestose (1‐kestotriose, GF 2 ), 1,1‐nystose (Der Agopian, Soares, Purgatto, Cordenunsi, & Lajolo, ), 6‐kestotriose, 6G‐kestotriose (older name, neokestose), bifurcose (1,6‐kestotetraose), inulobiose (F 2 ), and inulotriose (F 3 ) (Cruz‐Cárdenas et al, ; Der Agopian, Purgatto, Cordenunsi, & Lajolo, ). In addition, the banana shows low glycemic index (Hettiaratchi, Ekanayake, & Welihinda, ), positive effect on the fecal microbiota of healthy adult women when consumed daily (Mitsou et al, ) and contribute to maintain a good performance when consumed before or during physical exercise (Nieman et al, ).…”

“…The banana pulp is mentioned as a source of FOS, however, significant differences were observed in the reported quantities: 10.90 mg/g dw (Campbell et al, ), 1.30 mg/g FOS in banana puree (Hogarth, Hunter, Jacobs, Garleb, & Wolf, ), 4.30–6.02 mg/g dw in bananas at different maturity stages (L'homme, Peschet, Puigserver, & Biagini, ), 0.30–1.63 mg/g dw in different banana cultivars (Der Agopian, Soares, Purgatto, Cordenunsi, & Lajolo, ), and 27.63–80.92 µg/g dw in different accessions of banana (Cruz‐Cárdenas et al, ). The different amount of FOS can be due to the cultivar, stage of ripening, processing, and methodologies applied in the analysis (Der Agopian et al, ).…”

“…The occurrence of fructans in banana pulp is well‐documented in the literature (Campbell et al, ; Cruz‐Cárdenas et al, ; Der Agopian et al, ; Hogarth, Hunter, Jacobs, Garleb, & Wolf, ; L'homme, Peschet, Puigserver, & Biagini, ); however, minimal information is available about the presence of other oligosaccharides such as galactooligosaccharides (GOS), maltooligosaccharides (MOS), and xylooligosaccharides (XOS). Furthermore, according to our own literature search, no study was found dealing with oligosaccharides profile in banana peel.…”

Bacterial cellobiose metabolism: An inquiry‐driven, comprehensive undergraduate laboratory teaching approach to promote investigative learning

“…Method Summary: The extracellular medium was analyzed to identify the chemical nature of the transformation of cellobiose carbon source as a function of growth time using HPLC and 1 H‐NMR spectroscopy (Fig. ).…”