Biobased Materials from Microbial Biomass and Its Derivatives

Abstract

There is a strong public concern about plastic waste, which promotes the development of new biobased materials. The benefit of using microbial biomass for new developments is that it is a completely renewable source of polymers, which is not limited to climate conditions or may cause deforestation, as biopolymers come from vegetal biomass. The present review is focused on the use of microbial biomass and its derivatives as sources of biopolymers to form new materials. Yeast and fungal biomass are low-cost and abundant sources of biopolymers with high promising properties for the development of biodegradable materials, while milk and water kefir grains, composed by kefiran and dextran, respectively, produce films with very good optical and mechanical properties. The reasons for considering microbial cellulose as an attractive biobased material are the conformational structure and enhanced properties compared to plant cellulose. Kombucha tea, a probiotic fermented sparkling beverage, produces a floating membrane that has been identified as bacterial cellulose as a side stream during this fermentation. The results shown in this review demonstrated the good performance of microbial biomass to form new materials, with enhanced functional properties for different applications.

The Type and Concentration of Inoculum and Substrate as Well as the Presence of Oxygen Impact the Water Kefir Fermentation Process

“…Water kefir grain mass can be considered as a waste stream, as the usual goal of water kefir fermentation is the production of liquor for its use as beverage. Nevertheless, the production of grains is sometimes desirable, for example to scale up a water kefir production process ( Laureys et al, 2017 ) or for the production of novel biobased materials ( Cottet et al, 2020 ). To reduce water kefir grain growth during fermentation, sucrose may be (partially) substituted with glucose and/or fructose, as sucrose is necessary for dextran EPS production ( Monsan et al, 2001 ).…”

Bacterial Nanocellulose toward Green Cosmetics: Recent Progresses and Challenges

“…Another property of BNC that stands out over plant cellulose is its high chemical purity, being free of lignin, hemicelluloses, and pectin, typically present in plant fibers [ 14 ]. This eliminates the need for complex purification procedures, which are energy and chemically demanding, with reduced yields that may affect the structure and physicochemical properties of cellulose [ 72 ].…”

PRODUCTION OF Candida BIOMASSES FOR HEAVY METAL REMOVAL FROM WASTEWATERS

“…Biomasses have some advantages such as high efficiency, minimal sludge formation, regeneration, and no additional supplementary of nutrients (Tripathi & Ranjan 2015). Yeasts which are used in the enzymatic industry and medicine can survive in a medium containing low or high concentrations of heavy metals (Cottet et al 2020). One of the most important microbial source for biosorption of heavy metals is Candida species (Luna et al 2016), which were shown to play an important role in the accumulation of metal ions (Honfi et al 2016, Luk et al 2017.…”

“…The constant Ks is the saturation constant or half of the velocity constant and is equal to the concentration of the ratelimiting substrate when the specific growth rate is equal to one-half of the maximum specific growth rate (Monod 1949, Liu 2007. Microorganism cell consists of an outer cover called a cell wall and contains a variety of functional sites such as amines, phosphates, sulfates, phenols, and hydroxyls with the ability for adsorption of metal ions (Javanbakht et al 2013, Cottet et al 2020).…”