A Screening Method for the Isolation of Bacteria Capable of Degrading Toxic Steroidal Glycoalkaloids Present in Potato

Abstract

Potato juice, a by-product of starch processing, is a potential high-value food ingredient due to its high protein content. However, conversion from feed to human protein requires the removal of the toxic antinutritional glycoalkaloids (GAs) α-chaconine and α-solanine. Detoxification by enzymatic removal could potentially provide an effective and environmentally friendly process for potato-derived food protein production. While degradation of GAs by microorganisms has been documented, there exists limited knowledge on the enzymes involved and in particular how bacteria degrade and metabolize GAs. Here we describe a series of methods for the isolation, screening, and selection of GA-degrading bacteria. Bacterial cultures from soils surrounding greened potatoes, including the potato peels, were established and select bacterial isolates were studied. Screening of bacterial crude extracts for the ability to hydrolyze GAs was performed using a combination of thin layer chromatography (TLC), high performance liquid chromatography (HPLC), and liquid chromatography mass spectrometry (LC-MS). Analysis of the 16S rRNA sequences revealed that bacteria within the genus Arthrobacter were among the most efficient GA-degrading strains.

The Combination of Lead and Bacillus coagulans R11 Increased the Concentration of Alpha-Solanine in the Cecum of Laying Hens and the Pathogens Abundance Decreased

“…The results showed that the concentration of α-solanine in the cecum increased obviously with B. coagulans R11 feeding. α-Solanine was one of the alkaloids that can be commonly found in potatoes, and most previous studies focused on only the degradation of α-solanine (Hennessy et al, 2018(Hennessy et al, , 2019. Hennessy found that Arthrobacter sp.…”

Draft Genome Sequences of Two Glycoalkaloid-Degrading Arthrobacter Strains Isolated from Green Potato Peel

“…To convert starch side streams from feed to food, antinutritional factors, including GAs, must be removed. While fungal pathogens are known to degrade potato-derived GAs, little information on bacterial enzymes is available (2). This announcement reports the draft genome sequences of two Arthrobacter strains (S39 and S41) which are capable of degrading α-chaconine and α-solanine.…”

“…S39 and Arthrobacter sp. S41 were isolated from green potato peel (2). Genomic DNA was purified from liquid cultures grown at 20°C in lysogenic broth (LB) using the Gentra Puregene Yeast/Bact.…”

Draft Genome Sequence of a Novel Serratia sp. Strain with Antifungal Activity

“… Serratia sp. strain S40 was isolated from a potato rhizosphere in Zealand, Denmark ( 5 ). For whole-genome sequencing, the strain was cultivated in lysogeny broth (LB) for 24 h at 20°C before DNA extraction.…”

“…Genomic DNA was purified using the Gentra Puregene Yeast/Bact. kit (Qiagen, Germany) according to the manufacturer’s instructions, and purified genomic DNA was verified by 16S RNA gene sequencing as previously described ( 5 ). Library preparation for whole-genome sequencing was performed using the Nextera DNA library prep kit (Illumina, Inc., San Diego, CA, USA).…”