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An efficient bioprocess using immobilized lactic acid bacteria to obtain 5-iodouracil-2′-deoxyriboside, known as idoxuridine, is reported. This nucleoside analogue is an antiviral agent used in the treatment of viral infections in the absence of efficient vaccines. Idoxuridine conversion was close to 90% in different nonconventional media. A bionanocomposite (alginate-nanoclay) was employed as matrix to stabilize Lactobacillus animalis ATCC 35046 with improved stability in the presence of organic cosolvents. In this study, an eco-compatible and alternative bioprocess to obtain idoxuridine was developed for the first time. The scale-up biosynthesis of idoxuridine afforded a product yield close to 0.4 gr/L in the presence of 20% of DMSO. [ABSTRACT FROM AUTHOR]

The effect of natural and lactic acid bacteria ( LAB) fermentation processes on metabolite changes in pastes of soybeans and soybean-maize blends was studied. Pastes composed of 100% soybeans, 90% soybeans and 10% maize, and 75% soybeans and 25% maize were naturally fermented ( NFP), and were fermented by lactic acid bacteria ( LFP). LAB fermentation processes were facilitated through back-slopping using a traditional fermented gruel, thobwa as an inoculum. Naturally fermented pastes were designated 100S, 90S, and 75S, while LFP were designated 100 SBS, 90 SBS, and 75 SBS. All samples, except 75 SBS, showed highest increase in soluble protein content at 48 h and this was highest in 100S (49%) followed by 90 SBS (15%), while increases in 100 SBS, 90S, and 75S were about 12%. Significant ( P < 0.05) increases in total amino acids throughout fermentation were attributed to cysteine in 100S and 90S; and methionine in 100S and 90 SBS. A 3.2% increase in sum of total amino acids was observed in 75 SBS at 72 h, while decreases up to 7.4% in 100 SBS at 48 and 72 h, 6.8% in 100S at 48 h and 4.7% in 75S at 72 h were observed. Increases in free amino acids throughout fermentation were observed in glutamate ( NFP and 75 SBS), GABA and alanine ( LFP). Lactic acid was 2.5- to 3.5-fold higher in LFP than in NFP, and other organic acids detected were acetate and succinate. Maltose levels were the highest among the reducing sugars and were two to four times higher in LFP than in NFP at the beginning of the fermentation, but at 72 h, only fructose levels were significantly ( P < 0.05) higher in LFP than in NFP. Enzyme activities were higher in LFP at 0 h, but at 72 h, the enzyme activities were higher in NFP. Both fermentation processes improved nutritional quality through increased protein and amino acid solubility and degradation of phytic acid (85% in NFP and 49% in LFP by 72 h). [ABSTRACT FROM AUTHOR]

The production of rice-based beverages fermented by lactic acid bacteria (LAB) can increase the consumption of rice in the form of a dairy replacement. This study investigated volatile and nonvolatile components in rice fermented by 12 different LABs. Volatile compounds of fermented rice samples were analyzed using gas chromatography-mass spectrometry (GC-MS) combined with solid-phase microextraction (SPME), while nonvolatile compounds were determined using gas chromatography-time-of-flight/mass spectrometry (GC-TOF/MS) after derivatization. The 47 identified volatile compounds included acids, aldehydes, esters, furan derivatives, ketones, alcohols, benzene and benzene derivatives, hydrocarbons, and terpenes, while the 37 identified nonvolatile components included amino acids, organic acids, and carbohydrates. The profiles of volatile and nonvolatile components generally differed significantly between obligatorily homofermentative/facultatively heterofermentative LAB and obligatorily heterofermentative LAB. The rice sample fermented by Lactobacillus sakei (RTCL16) was clearly differentiated from the other samples on principal component analysis (PCA) plots. The results of PCA revealed that the rice samples fermented by LABs could be distinguished according to microbial strains. [ABSTRACT FROM AUTHOR]