Bacterial cellulose production by Gluconacetobacter xylinus by employing alternative culture media

Abstract

Bacterial cellulose (BC) is used in different fields as a biological material due to its unique properties. Despite there being many BC applications, there still remain many problems associated with bioprocess technology, such as increasing productivity and decreasing production cost. New technologies that use waste from the food industry as raw materials for culture media promote economic advantages because they reduce environmental pollution and stimulate new research for science sustainability. For this reason, BC production requires optimized conditions to increase its application. The main objective of this study was to evaluate BC production by Gluconacetobacter xylinus using industry waste, namely, rotten fruits and milk whey, as culture media. Furthermore, the structure of BC produced at different conditions was also determined. The culture media employed in this study were composed of rotten fruit collected from the disposal of free markets, milk whey from a local industrial disposal, and their combination, and Hestrin and Schramm media was used as standard culture media. Although all culture media studied produced BC, the highest BC yield-60 mg/mL-was achieved with the rotten fruit culture. Thus, the results showed that rotten fruit can be used for BC production. This culture media can be considered as a profitable alternative to generate high-value products. In addition, it combines environmental concern with sustainable processes that can promote also the reduction of production cost.

Bacterial Cellulose Production by Komagataeibacter hansenii ATCC 23769 Using Sisal Juice - An Agroindustry Waste

“…SI fermentative medium increased the BC yield by around 2.3-fold in comparison to the SM and by around 5.6-fold in comparison to the HS. According to the literature, the BC production and yields may vary depending on the sugar source used and the conditions of the fermentation process (Jozala et al, 2015). Yield decreased from 66% to 30% from the 2 nd to the 4 th day of culture of G. xylinus ATCC 53524 in HS and the most significant increase happened in the first 4 days of culture.…”

“…Also, the addition of antioxidant compounds in the fermentative medium favored the production of BC because the antioxidants inhibit the formation of gluconic acid (Jozala et al, 2015;Keshk and Sameshima, 2006). Species from the genus Agave are sources of antioxidant compounds with inhibitory activity against oxidative enzymes (Santos et al, 2012), while bacteria from the genus Komagataeibacter can metabolize tannins, which accounts for their resilience and development in agroindustrial media (Usha and Appaiah, 2012).…”

“…Sisal juice can be considered as a potential substrate for production of BC because the producing bacteria from Komagataeibacter generally require a source of sugars and nitrogen to be present in the medium (Jozala et al, 2015;Kurosumi et al, 2009;Çoban and Biyik, 2011). Media with sugar levels ranging from 10 to 20 g/L may provide an optimal condition for BC production, as demonstrated in different studies (Jung et al, 2010;Keshk and Sameshima, 2006;Jung et al, 2005).…”

“…In many cases, it is possible to achieve similar or superior production of BC when compared to methods using synthetic media. The use of alternative carbon sources in fermentation processes is important because this can reduce the environmental impact from the disposal of agro-industrial wastes, reduce the final cost of the product, and add value to the supply chains involved (Jozala et al, 2015).…”

“…To reduce production costs, research projects have evaluated agroindustrial sources as alternative culture media for BC production. Examples of agro-industrial sources studied include: fruit juices (Jozala et al, 2015;Kurosumi et al, 2009), molasses (Çakar et al, 2014), molasses-corn steep liquor (Bae and Shoda, 2004;Jung et al, 2010), aqueous extract from grape skins, cheese whey, crude glycerol, sulfite pulping liquor (Jozala et al, 2015;Carreira et al, 2009), pineapple peel juice, sugar cane juice (Castro et al, 2011), coconut juice (Kongruang, 2008), waste beer yeast (Lin et al, 2014), maple syrup (Zeng et al, 2011), hydrolyzed starch, and coconut water (Hungund, 2013). In many cases, it is possible to achieve similar or superior production of BC when compared to methods using synthetic media.…”