There are many functions of pectin, but its structure is not very familiar to everyone. We are a  pectin manufacturer and will introduce the structure and use of the supplier’s pectin.


The structure of supplier’s pectin

Although pectin has been discovered for nearly 200 years, its composition and structure have not been fully understood at present. The reason pectin structures are so difficult to parse is that their structure and composition vary with plant species, storage periods and processing techniques. In addition, there are some impurities in pectin. According to the different structure of the main chain and branch chain of pectin molecules, they are divided into 4 categories: Homogalacturonan, HG, Rhamngalacturonan I, RGI, Rhamngalacturonan II, RGII and Xylogalacturonan, XG.


The first pectin’s structure is HG. HG is a long, continuous and smooth galacturonic acid polymer linked by α-1,4 glycosidic bonds, accounting for about 65% of pectin. The C6 of galacturonic acid can methyl ester or amid. In some plants, C2 or C3 can acetyl. Studies have also found that the O-3 or O-4 of the galacturonic acid residue in HG is replaced by xylose to form XG.


The second pectin’s structure is RGI. RGI (20%~35%) is a skeleton with side chain regions. It is compose of dozens or even more than 100 repeated rhamnogalacturonic acid disaccharides. Usually 20%~80% of the rhamnose residues in RGI are replace by neutral sugar branches. Besides, the substitution position is usually at the C4 position. The length and type of branched chains of RGI are related to the source of pectin raw materials and extraction methods. These branches can divid into 3 types of polymers: arabinan, arabinogalactan I and arabinogalactan II.

Arabinogalactan I

The third pectin’s structure is arabinogalactan I. Arabinogalactan I is compose of (1,4)-α-D-Gal-(1,5)-α-L-Ara. It is connect to the main chain through (1,4)-α-L-Ara. Arabinogalactan II is a highly branche galactan. The main chain of the side chain is compose of (1,3)-α-D-Gal. And then the main chain is replace by (1,6)-α-D-Gal as a branch. The branch was replace by (1,3)-α-L-Ara.

Besides, the another pectin’s structure is RGII. The structure of RGII (about 10%) is very complicate. Because its backbone is a short and elongated HG with 4 different side chains. Moreover, not Rhamngalacturonan. RGII is connect by at least 12 types of monosaccharides in more than 20 types of bonding. In plants, RGII can cross-link with borate.

About us

The above is a brief introduction to the structure of pectin. As one of the best pectin wholesalers in China. You can trust the quality of our company’s products. If you want to buy it or want to know more product information, please feel free to contact us.