Assessment of vine shoots and surplus grape must for succinic acid bioproduction

Abstract

Vine shoots and surplus grape must were assessed as feedstocks for succinic acid production with Actinobacillus succinogenes and Basfia succiniproducens. After acidic and enzymatic hydrolysis, vine shoots released 35-40 g/L total sugars. Both bacterial species produced 18-21 g/L succinic acid from this hydrolysate in 120 h. Regarding grape must fermentation, A. succinogenes clearly outperformed B. succiniproducens. Yeast extract was the only additional nutrient needed by A. succinogenes to grow on grape must. Under mathematically optimized conditions (145.7 g/L initial sugars and 24.9 g/L yeast extract), A. succinogenes generated 88.9 ± 1.4 g/L succinic acid in 96 h, reaching a succinic acid yield of 0.66 ± 0.01 g/g and a sugar consumption of 96.64 ± 0.30 %. Substrate inhibition was not observed in grape musts with 125-150 g/L initial sugars, provided that an adequate amount of yeast extract was available for bacteria. Alternative nitrogen sources to yeast extract (red wine lees, white wine lees, urea, NH4Cl and choline chloride) were not suitable for A. succinogenes in grape must.

Enhancing Succinic Acid Production by Sequential Adaptation of Selected Basfia succiniciproducens Strains to Arundo donax Hydrolysate

“…The 4D strain exhibited a yield of approximately 31%, whereas the native strain achieved a yield of 25% per kg of dry A. donax. The total amount of succinic acid produced by B. succiniciproducens 4D from A. donax hydrolysate depends on the type of feedstock, which is characterized by low initial sugar concentration and is a limiting factor in obtaining higher succinic acid values [8]. The use of new biocatalysts, which are more effective in the hydrolyzed phase, as well as new bacterial strains adapted to the toxic chemicals, can make the bioconversion processes of lignocellulosic-rich biomass more competitive.…”

“…Furthermore, succinic acid was recognized by the US Department of Energy as an important building block that can be produced from biomass in biorefineries. As a result, several companies have tried to produce it on an industrial scale, with varying degrees Fermentation 2023, 9, 573 2 of 15 of success [8]. Bio-based succinic acid production is currently estimated at 36,600 tonnes using various bacterial strains [9,10].…”

“…This technology has significant potential for improving microbial production performance [13,36]. To the best of our knowledge, only Roquette, BASF, and PTT-MCC Biochem continue to operate their bio-succinic acid production facilities, primarily using metabolically engineered strains [8]. Genetic engineering is widely employed to develop new bacterial strains, known as genetically engineered microorganisms (GEMs), with unique characteristics compared to the wild type, such as the ability to produce more succinic acid or to tolerate the presence of inhibitors in the growth medium [36].…”

“…Furthermore, it has been widely reported that the presence of inhibitors from lignocellulosic biomass [15], secondary metabolites, auxotrophy, pH sensitivity, and product inhibition have affected various engineered hosts [8].…”

Cell Immobilization for Erythritol Production

“…Moniliella can produce erythritol in the presence of various nitrogen sources, such as yeast extract, corn steep liquor, urea, malt extract and ammonium sulphate [7,[12][13][14]. Although yeast extract is an excellent source of nitrogen and vitamins for many microbial processes [28,29], it is also a costly reagent, whose estimated price for industries in Spain is EUR 7/kg (~7 $/kg) [30]. However, the process costs could be reduced remarkably if cheaper nitrogen sources were employed.…”