Green Formulation Strategy for Preparing Oil-in-Water Emulsions via Lipase-Catalyzed Transesterification

Formulation of submicronic diglyceride-in-water emulsions was carried out without addition of synthetic surfactant in case of commercial caprylic/capric diglyceride. Sugar surfactant was prepared by contacting the oil with a concentrated aqueous solution of sorbitol (70 wt %) containing lipase AY. Interfacial lipase-catalyzed transesterification took place and led to limited but sufficient amounts of sorbitol ester and monoglyceride, which accumulated in the oil. The enzyme-treated oil could be easily separated from the aqueous phase and used for preparing oil-in-water emulsion without adding any other surfactant. A stable emulsion was obtained for at least 7 days and exhibited better stability at 60 °C than Tween 20-stabilized emulsion

Data_Sheet_1_Exploring untapped bacterial communities and potential polypropylene-degrading enzymes from mangrove sediment through metagenomics analysis.docx

The versatility of plastic has resulted in huge amounts being consumed annually. Mismanagement of post-consumption plastic material has led to plastic waste pollution. Biodegradation of plastic by microorganisms has emerged as a potential solution to this problem. Therefore, this study aimed to investigate the microbial communities involved in the biodegradation of polypropylene (PP). Mangrove soil was enriched with virgin PP sheets or chemically pretreated PP comparing between 2 and 4 months enrichment to promote the growth of bacteria involved in PP biodegradation. The diversity of the resulting microbial communities was accessed through 16S metagenomic sequencing. The results indicated that Xanthomonadaceae, unclassified Gaiellales, and Nocardioidaceae were promoted during the enrichment. Additionally, shotgun metagenomics was used to investigate enzymes involved in plastic biodegradation. The results revealed the presence of various putative plastic-degrading enzymes in the mangrove soil, including alcohol dehydrogenase, aldehyde dehydrogenase, and alkane hydroxylase. The degradation of PP plastic was determined using Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electron Microscopy (SEM), and Water Contact Angle measurements. The FTIR spectra showed a reduced peak intensity of enriched and pretreated PP compared to the control. SEM images revealed the presence of bacterial biofilms as well as cracks on the PP surface. Corresponding to the FTIR and SEM analysis, the water contact angle measurement indicated a decrease in the hydrophobicity of PP and pretreated PP surface during the enrichment.</p

Bacteria Interface Pickering Emulsions Stabilized by Self-assembled Bacteria–Chitosan Network

An oil-in-water Pickering emulsion stabilized by biobased material based on a bacteria–chitosan network (BCN) was developed for the first time in this study. The formation of self-assembled BCN was possible due to the electrostatic interaction between negatively charged bacterial cells and polycationic chitosan. The BCN was proven to stabilize the tetradecane/water interface, promoting formation of highly stable oil-in-water emulsion (o/w emulsion). We characterized and visualized the BCN stabilized o/w emulsions by scanning electron microscopy (SEM) and laser scanning confocal microscopy (LSCM). Due to the sustainability and low environmental impact of chitosan, the BCN-based emulsions open up opportunities for the development of an environmental friendly new interface material as well as the novel type of microreactor utilizing bacterial cells network