Optimization of Reduced Glutathione Production by a Lactobacillus plantarum Isolate Using Plackett–Burman and Box–Behnken Designs

Abstract

In this work, we aim to optimize the production of reduced glutathione (GSH) synthesized intracellularly by a food-grade microorganism through a statistical approach. Using a colorimetric method, 25 Lactobacillus plantarum isolates were screened in an attempt to find a GSH-producing strain. It was found that 36% of the tested isolates showed positive result. Isolate (L7) was found to produce 152.61 μM glutathione per gram which was the highest amount produced intracellularly. Accordingly, the later isolate was selected for the optimization process using Plackett–Burman and Box–Behnken designs. Temperature, amino acids, and urea were found to be the most significant independent variables. Following data analysis, the composition of the optimized medium was De Man-Sharp-Rogosa broth as a basal medium supplemented with NaCl (5%), H2O2 (0.05%), sodium dodecyl sulfate (0.05%), amino acids (0.0281%), and urea (0.192%). The pH of the medium was adjusted to 8 and incubated for 24 h at 40°C. The GSH amount was increased by 10-fold (851%) using the optimized medium. Hence, our optimization design estimated the biotechnological potential of L. plantarum (L7) for the production of GSH in the industry.

Isolation of lactic acid bacteria capable of reducing environmental alkyl and fatty acid hydroperoxides, and the effect of their oral administration on oxidative-stressed nematodes and rats

“…There are several excellent antioxidant investigations in lactic acid bacteria [7,8,[26][27][28][29][30]. The glutathione production [31], expression of glutathione peroxidase and reductase genes [32] and inhibition capacity for lipid peroxidation in L. plantarum [32] were recently reported. However, it remains unknown whether the glutathione system participates in a reduction of lipid peroxide in L. plantarum.…”

Genome and Pangenome Analysis of Lactobacillus hilgardii FLUB—A New Strain Isolated from Mead

“…This has a number of interesting consequences, since these genes play an important role in various physiological processes. Among others, they provide a reduced cellular environment, with glutathione acting as an antioxidant protecting biomolecules, DNA, and proteins from oxidative damage [ 64 ]. The glutamate-cysteine ligase gene is chromosomally coded (GQR93_00790, GQR93_00800, GQR93_00810), while the gshAB gene is located on plasmid 1.…”

A statistical approach to improve compound screening in cell culture media

“…A two‐time replicated 24‐run folded‐over PBD (Table ) was used to identify the compounds with a significant effect on CHO‐S cell growth and screen out negligible factors . The eight compounds were screened at two levels: a low level (no additive) coded as −1 and a high level coded as +1.…”

“…However, full factorial and 2 k fractional designs require a high experimental effort when there are many k factors to be analyzed . In this case, D‐optimal Plackett–Burman designs (PBDs) become a useful alternative . Still, PBDs are saturated designs developed to eliminate factors potentially having no or negligible effects over the responses.…”

“…Still, PBDs are saturated designs developed to eliminate factors potentially having no or negligible effects over the responses. This means that only main effects are to be considered, which implies to ignore aliasing patterns due to higher order interactions . Rejecting this possible scenario, which is very common in media optimization , may guide upcoming experimentation to an incorrect decision.…”