Biocycle Fermentation Based on Lactic Acid Bacteria and Yeast for the Production of Natural Ethyl Lactate

Ethyl lactate is widely used in food and pharmaceutical industries, but the complexity of the synthesis process, in particular, involving the addition of organic solvents, hinders its application. Here, we report a natural green strategy to produce ethyl lactate by exploiting the synergistic fermentation of lactic acid bacteria and ester-producing microbes using biomass as a substrate. Interestingly, it is worth noting that the conjugate fermentation has a higher ethyl lactate yield (3.05 g/L) compared to the mixed fermentation (1.32 g/L). The ester production capacity was increased by 2.3 times. These entire processes require only the addition of biomass without introducing any organic solvent. In addition, the obtained catalytic esterification system can reuse the ester-producing microbes by simple centrifugation and maintain over seven cycles of catalysis while it retained a high activity. We firmly believe that the results of this study will provide new ideas for achieving sustainable green production of natural ethyl lactate.

Chemical and bio-chemical reactions assisted by pervaporation technology

Since several decades ago, the application of pervaporation (PV) technology has been mainly aimed at the separation of different types of water-organic, organic-water and organic-organic mixtures, reaching its large-scale application in industry for the dehydration of organics. Today, the versatility and high selectivity toward specific compounds have led its consideration to other types of application such as the assisted chemical and bio-chemical reactions. The focus of this review is to provide a compelling overview on the recent developments of PV combined with chemical and bio-chemical reactions. After a general introduction of PV and its theoretical background, particular emphasis is given to the results obtained in the field for different reactions considered, identifying the key features and weak points of PV in such particular applications. Furthermore, future trends and perspectives are also addressed according to the latest literature reports.

Potential of Pervaporation and Vapor Separation with Water Selective Membranes for an Optimized Production of Biofuels—A Review

The development of processes based on the integration of new technologies is of growing interest to industrial catalysis. Recently, significant efforts have been focused on the design of catalytic membrane reactors to improve process performance. In particular, the use of membranes, that allow a selective permeation of water from the reaction mixture, positively affects the reaction evolution by improving conversion for all reactions thermodynamically or kinetically limited by the presence of water. In this paper, how pervaporation (PV) and vapor permeation (VP) technologies can improve the catalytic performance of reactions of industrial interest is considered. Specifically, technological approaches proposed in the literature are discussed with the aim of highlighting advantages and problems encountered in order to address research towards the optimization of membrane reactor configurations for liquid biofuel production in large scale.