Isolation, Identification, and Evaluation of The Ability toProduce Xanthan Gum from Lactose by Xanthomonas campestrisIsolated from Plants Infected by Bacterial Canker

Background and Aim : Xanthan gum is a polysaccharide with many industrial uses, including asa common food additive. It is an effective thickening agent, emulsifier, and stabilizer whichprevents ingredients from separating. It can be produced from simple sugars using a fermentationprocess and derives its name from the species of bacteria used, Xanthomonas campestris. Thisstudy aimed to isolate, identify and evaluate the amount of xanthan gum production from lactoseby Xanthomonas campestris Isolated from Plants Infected by Bacterial Canker.Methods : : Leaves of trees infected with bacterial canker were collected from an orange gardenin the north of Iran. The initial isolation was done using culture in glucose-yeast extract agarmedium. Then, the isolated strains with the ability to produce xanthan gum were identified basedon biochemical and molecular tests. Finally, the production of xanthan gum was done using lactoseas a substrate.Results : In this study, ۳۵ bacterial strains were isolated. Among them, ۲۰ strains were able toproduce xanthan gum. Based on biochemical and molecular tests, ۶ strains were identified asXanthomonas campestris. Among these strains, only ۱ could use lactose as substrate, and theamount of xanthan gum production in this strain was ۸.۷g/l.Conclusion : The results showed that the isolated bacteria have a good potential in the productionof xanthan gum from lactose and this amount can be increased by optimizing different productionconditions.

کلیدواژه ها:

Xanthan gum ، Xanthomonas campestris ، lactose ، plant