Three of the major ligninolytic enzymes, lignin peroxidase (LiP), manganese peroxidase (MnP), and laccase (LA), as well as the secretome of a white-rot fungi, Grammothele fuligo, are tested on three industrial lignins (organosolv, alkali, and Kraft), to investigate and study the differences in biodegradation reactions and mechanism of these three lignins. Strategies involving additives in laccase mediated systems were also considered to produce small phenolic compounds. Three new or underreported additives including 2,4,6-tri-tert-butylphenol (TTBP), 4-tert-butyl-2,6-dimethylphenol (TBDMP), and 3hydroxyanthranilic acid (HAA) are compared to three classic laccase mediators violuric acid (VA), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and 1-hydroxybenzotriazole (1-HBT). Decrease of molecular weight by up to 73% could be obtained on organosolv lignin with LA−VA systems, and by 49%, 43%, and 39% when LA was used with ABTS, TBDMP, and 1-HBT, respectively. In-depth analysis of the degradation products by quantitative 2D HMQC NMR indicated that the oxidation is mediator-dependent and provides new insights on the enzymatic mechanism.

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Straightforward and sustainable two-step route to bioactive sinapoyl-l-malate and analogues using Meldrum's acid opening and Knoevenagel-Doebner condensation.

An experimental design based on Response Surface Methodology (RSM) was used for the formulation of a growth medium based on sugar beet and wheat processing coproducts adapted to the cultivation of Lactobacillus reuteri (L. reuteri) DSM17938. The strain was cultivated on 30 different media varying by the proportions of sugar beet and wheat processing coproducts, and the concentration of yeast extract, tween 80 and vitamin B12. The media were used in a two-step process consisting of L. reuteri cultivation followed by the bioconversion of glycerol into 3-hydroxypropionic acid by resting cells. The efficiency of the formulations was evaluated according to the maximal optical density at the end of the growth phase (∆OD 620nm ) and the ability of the resting cells to convert glycerol into 3-hydroxypropionic acid, a platform molecule of interest for the plastic industry. De Man, Rogosa, and Sharpe medium (MRS), commonly used for the cultivation of lactic bacteria, was used as the control medium. The optimized formulation allowed increasing the 3-HP production.