A wide diversity exists in pectin structure from thirteen apple cultivars

Dazhi Liu; Xuan Liu; Jianing Liu; Éva Jermendi; Jinfeng Bi; Henk A Schols

doi:10.1016/j.ijbiomac.2023.125410

A wide diversity exists in pectin structure from thirteen apple cultivars

Int J Biol Macromol. 2023 Jul 31:244:125410. doi: 10.1016/j.ijbiomac.2023.125410. Epub 2023 Jun 14.

Authors

Dazhi Liu¹, Xuan Liu², Jianing Liu³, Éva Jermendi⁴, Jinfeng Bi², Henk A Schols⁵

Affiliations

¹ Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences (CAAS), Key Laboratory of Agro-Products Processing, Ministry of Agriculture and Rural Affairs, Beijing 100193, China; Laboratory of Food Chemistry, Wageningen University & Research, Bornse Weilanden 9, 6708, WG, Wageningen, the Netherlands.
² Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences (CAAS), Key Laboratory of Agro-Products Processing, Ministry of Agriculture and Rural Affairs, Beijing 100193, China.
³ Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences (CAAS), Key Laboratory of Agro-Products Processing, Ministry of Agriculture and Rural Affairs, Beijing 100193, China; Food Quality and Design Group, Wageningen University & Research, Bornse Weilanden 9, 6708, WG, Wageningen, the Netherlands.
⁴ Laboratory of Food Chemistry, Wageningen University & Research, Bornse Weilanden 9, 6708, WG, Wageningen, the Netherlands.
⁵ Laboratory of Food Chemistry, Wageningen University & Research, Bornse Weilanden 9, 6708, WG, Wageningen, the Netherlands. Electronic address: henk.schols@wur.nl.

PMID: 37327923
DOI: 10.1016/j.ijbiomac.2023.125410

Abstract

To emphasize that differences in pectin structure among cultivars play a crucial role in the texture and quality of fruits and vegetables, the sugar content and methyl-esterification of pectin fractions from 13 apple cultivars was studied. Cell wall polysaccharides were isolated as alcohol-insoluble solids (AIS) and subsequently extracted to yield water-soluble solids (WSS) and chelating-soluble solids (ChSS). All fractions contained significant amounts of galacturonic acid, while sugar compositions varied between cultivars. AIS and WSS pectins showed a degree of methyl-esterification (DM) > 50 %, while ChSS pectins had either a medium (∼50 %) or low (<30 %) DM. Homogalacturonan as major structure was studied using enzymatic fingerprinting. Methyl-ester distribution of pectin was described by degrees of blockiness and -hydrolysis. Novel descriptive parameters were obtained by measuring the levels of methyl-esterified oligomers released by endo-PG (DB_PGme) and PL (DB_PLme). Pectin fractions differed in relative amounts of non-, moderately-, and highly methyl-esterified segments. WSS pectins were mostly lacking non-esterified GalA sequences, while ChSS pectins had medium DM and many non-methyl-esterified blocks or a low DM with many intermediate methyl-esterified GalA blocks. These findings will be of help to better understand physicochemical properties of apple and its products.

Keywords: Apple pectin; Enzymatic fingerprinting; Structure characterisation.

MeSH terms

Fruit / chemistry
Malus*
Pectins / chemistry
Polysaccharides / analysis
Sugars / analysis

Substances

Pectins
Polysaccharides
Sugars