Chemical, enzymatic, and antioxidant enrichments of full-fat soybean and sunflower meal by Bacillus subtilis (ATCC® 6633™) fermentation using a solid-state bioreactor

Abstract

In 2016, the world's soybean meal production reached 217 million tones and nearly half of it was used as protein supplement in farm animal nutrition (1). Sunflower meal (SFM), the fourth largest oilseed meal produced in the world, also serves as a protein source, mostly in ruminant diets, while its use in poultry and pig diets is limited (2). Chemical composition of these plant meals determines their levels in complete feeds fed to farm animals. For instance, soybean and its by-products may contain appreciable levels of phytic acid (PA) up to 0.6%, trypsin inhibitors (TI) up to 21.0-30.3 mg/g, protease inhibitors up to 45-60 mg/g protein, oligosaccharides up to 15%, lectins up to 50-200 mg/g, glycinin up to 150-200 mg/g, and beta-conglycin up to 50-100 mg/g (27.74 mg/g); these are known as antinutritional factors (ANFs) in young monogastric animals and reduce the rates of nutrient assimilation and absorption at the sites of digestive tract (3,4). SFM has a proportionally less crude protein (CP) in comparison to soybean meal, and its dietary inclusion level is low in poultry diets since it contains high level of crude fiber (CF) up to 18%-29% and polyphenolic compounds, mainly chlorogenic acid, up to 2.70% (2). In this study, possible improvements in nutritional qualities of SFM and full-fat soybean (FFSB) for farm animal nutrition were targeted by a fermentation process. Improved nutritional qualities of fermented FFSB (F-FFSB) and fermented SFM (FSFM) by solid-state fermentation (SSF) using GRAS (generally regarded as safe) microorganisms were reported earlier (5-7) and recently well documented by Mukherjee et al. (8). In addition, fermented feeds may contain biologically active compounds (biosurfactants, phenolic compounds, organic acids, enzymes) and less ANFs (9-14). The species of Lactobacillus and Bacillus are mostly used to ferment the feed materials (8,15,16). Recently, fermentation using Bacillus subtilis was found to be superior to fungal fermentation in terms of the increased soluble protein

Increased organic acid production and decreased phytate phosphorus by high level of water content of Bacillus subtilis ATCC PTA-6737 fermentation of soybean meal

“…spp., fermentations, similar to our results. Furthermore, Karakurt et al, (2019) demonstrated clearly that fixing pH at around 5.5 for Bacillus subtilis fermentation of both sunflower and soybean meal samples produced an appreciable amount of organic acids in the form of acetate, butyrate and lactate, similar to the results of pH and organic acids obtained from both moisture levels at 48 and 72 h of fermentation in our experiment.…”

“…In these studies, it was demonstrated that the ratio of added water to solid materials in SSF is crucial for improved metabolic activity of microorganism, and directly interacts together with oxygen for the removal of heat generated during the fermentation. In SSF, the water content of fermenting substrate is preferable above 60%, and moreover the optimal level of water content in SBM fermentation studies ranged from 75 to 85% water content (Amadou et al, 2010;Yasar et al, 2018;Karakurt et al, 2019).…”

A Fast and Robust FTIR-ATR Coupled Chemometric Determination of Chemical and Molecular Structure of Wheat (Triticum aestivum L.) under a Series of Microbial Fermentation Processes

“…This pattern of microbial growth was parallel to the pattern of CO2 production which was the highest at 24 hr (1% in AO, 4% in C+D, 6% in LBS and 4% in SC), thereby gradually decreased. Furthermore, organic acids produced by microbial fermentation such as lactic acid in our study (Table 2) have a negative impact on microbial growth by 48 hr fermentation (Karakurt et al, 2019). In general, the efficacy of fermentation can greatly be influenced by the type of microorganism used, temperature, pH and the rates of aeration and stirring (Krishna, 2005).…”

“…The conditions of temperature, pH, pressure and stirring in microbial fermentation are milder than that of a heat or chemical treatment wherein harsh conditions of food processing may cause undesirable Maillard reaction, yielding oxidised forms of amino acids (Sarwar Gilani et al, 2012). On the other hand, optimising pH, stirring rate, moisture level and temperature depending on the type and strain of microorganisms used and the expected outcome at the end of fermentation greatly affects the efficacy of microbial solid state fermentation using modern bioreactor (Yasar and Tosun, 2018;Karakurt et Open Access al., 2019). However, microbial fermentation is not always expected to result in both adding functionalities and causing nutritional fortifications.…”

Nutritional Enrichment of Apple Pomace by Fungal Fermentations

“…There are many studies reporting decreased crude fibre and its fractions by the solid-state fermentation (Lateef et al, 2008;Yasar and Tosun, 2018c;Karakurt et al, 2019). Altop et al (2018) reported that the starch and sugar content of industrial by-products were reduced as a result of fungal fermentation.…”