Effect of Nutrient Sources on the Alginate Accumulation in the Culture Liquid of Azotobacter vinelandii D-05 and Obtaining Biocomposite Materials

Abstract

Using the classic biotechnological methods, the dependence of A. vinelandii D-05 culture alginate production from the media carbon and nitrogen content was investigated. The maximal alginate production was observed during cultivation bacterium in the medium with 2 to 4% of sucrose, but the maximal growth was found in the medium with 4% glucose. It was found that for the alginate production the optimal nitrogen contents could take from 0.05% yeast extract (carbon: nitrogen ratio 168:1). For the first time we demonstrated possibility the A. vinelandii growth during the cultivation in a medium with molasses (a by-product of sugar production) and the significant polysaccharide production (16.6 g/l) was obtained. It was established, that A. vinelandii culture broth could be used as a biological binder for obtaining the biocomposite materials.

Alginate Production of Azotobacter vinelandii Using Sugar Cane Juice as the Main Carbon Source in an Airlift Bioreactor

“…The maximum alginate concentrations were 2.14 ± 0.07, 2.60 ± 0.43, 3.30 ± 0.14, 4.88 ± 0.07, and 3.03 ± 0.16 g L –1 obtained from the media with the initial sucrose concentrations of 7.5, 15.0, 30.0, 60.0, and 120.0 mM, respectively. The results obtained in this study concurred with those obtained by Moral et al and Revin et al who found that the highest alginate concentration was obtained from the media containing 60 mM sucrose, with no effects at a higher initial sucrose concentration. This indicated that the high sucrose concentration might deter both the growth and the alginate synthesis.…”

“…The variations in carbon metabolism influenced different enzyme activities in the production and polymerization of mannuronic acid, which is one of the monomers of alginate. Several studies have reported the effects of carbon source concentrations ,, and culture conditions and strategies on alginate production by A. vinelandii , such as strain, − nutrients, ,, aeration, − and bioreactor, ,, to produce diverse alginate yields.…”

Raman and FT-IR Spectroscopy investigation the cellulose structural differences from bacteria Gluconacetobacter sucrofermentans during the different regimes of cultivation on a molasses media

“…In this reason the next experiments the bacteria cultivation was carried out on a cheap medium with molasses, which as was shown has a positive effect on the synthesis of BC due to the polyphenols and sucrose (Coban, Biyik 2011;Zeng et al 2011). Molasses is traditionally used for cultivation of bacteria producing various polysaccharidesalginate (Revin et al 2018), levan (Revin et al 2016), dextran (Revin, Shutova 2015) and others. Also it is known that during bacteria cultivation in media with molasses, the changes of reducing sugars content leads to a decrease the gluconic acid production (Zeng et al 2011).…”

Media Cair Berbasis Molase untuk Meningkatkan Viabilitas dan Produksi Eksopolisakarida Azotobacter

“…Saat ini komposisi media untuk produksi pupuk hayati cair Azotobacter lebih ditujukan untuk meningkatkan jumlah sel dan aktivitas fiksasi N 2 pada media tanpa N atau dengan kadar N rendah. Berbeda dengan fiksasi N 2 , produksi EPS Azotobacter secara in vitro memerlukan N anorganik dengan konsentrasi tertentu (Khanafari dan Sepahei 2007;Revin et al 2018). Oleh karena itu formulasi inokulan cair Azotobacter untuk fungsi fiksasi N 2 dan produksi EPS perlu memperhatikan kadar N di media.…”