**3.4 Other applications of active ingredients produced from fermented plant extracts**

Another biotechnology application is the production of proteins, peptides, or AA such as GABA. Indeed, plant by-products are sources of different proteins, which can be hydrolyzed during fermentation by *Lactobacillus* species. These microorganisms, especially *L. plantarum,* have developed a proteolytic system to satisfy their nitrogen requirements. The proteolytic activities and protein hydrolysis patterns are very different from one strain to another. The resulting peptides displayed different biological functions such as angiotensin-converting enzyme inhibition, mineral binding, antidiabetic, satiating, immunomodulating, opioid, AO, or antimicrobial activities [12]. The *L. plantarum* LP-9 strain was used to coproduce GABA and lactic acid from agri-residues such as wheat bran, rice bran, corn bran. The results were compared with the use of cassava (starchy food crop), and the production yields were significant and comparable to this control condition [113]. Co-fermentation of Ginseng root and leaf extract always by *L. plantarum* EJ2014 and *B. subtilis,* also showed GABA production [114]. The fermentation of Kimchi by *L. brevis* BJ20 allows the conversion of glutamic acid into GABA. This process is particularly interesting because GABA has an AO activity demonstrated during the study of DPPH scavenging, superoxide scavenging, and xanthine oxidase inhibition tests [115]. Biotechnology also allows

Lactobacillus *Use for Plant Fermentation: New Ways for Plant-Based Product Valorization DOI: http://dx.doi.org/10.5772/intechopen.104958*

production of cosmetic or pharmaceutical products or surfactants. Biosurfactants production was investigated using *L. paracasei* on enzymatically hydrolyzed vineyard pruning waste. This study presented the complete process for this waste valorization using acid hydrolysis, delignification, and enzymatic hydrolysis steps. Authors have demonstrated the impact of the carbon source extraction process on the biosurfactant composition produced by the strain *L. paracasei* A20 [116].
