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Graphical abstract Highlights • Tissue adhesives are desired with low cytotoxicity and high tissue adhesion. • Catechol- and phenol-modified gelatin were synthesized respectively. • Adhesives were prepared via photochemistry or mussel-inspired chemistry. • Adhesives were evaluated by mechanical properties, tissue adhesion and toxicity. Abstract Tissue adhesives have been developed to overcome the difficulties of conventional wound closure techniques (e.g. sutures and staples), such as the potential for collateral damage and difficulty of stopping body fluid and gas. At the same time, it provides advantages such as simpler implementation, less painful, and does not require removal. However, representative adhesives such as cyanoacrylates and fibrin glues are plagued by cytotoxicity and low adhesion. In this study, we choose instead gelatin as the backbone of adhesive, due to its biocompatibility, biodegradability, and low cost. Firstly, catechol-modified gelatin and phenol-modified gelatin were synthesized via an EDC/NHS chemistry. Then, gelatin-based adhesives were prepared via ruthenium-based photochemistry, including photo-crosslinked gelatin (PG), phenol-modified gelatin (PPG), and catechol-modified gelatin (PCG). We also compared the photo-crosslinked adhesives to the recently reported ion-crosslinked catechol-modified gelatin. Our results indicate that gelatin-based adhesives demonstrate lower swelling index, great degradability, and low cytotoxicity. This shows that gelatin-based adhesives demonstrate great potential for wound closure and healing. [ABSTRACT FROM AUTHOR]

The antioxidative compounds were extracted by ultrasonic treatment of bran extracts of seven pigmented (completely) and non pigmented (sparsely) colored rice cultivars followed by assessment of their in vitro antioxidative capacity by LC-MS and oxidation/reduction assay based methods. A total of 40-compounds, 7-phenolic, 9-flavonoids, 9-hydroxycinammic acid derivatives, 3-hydroxybenzoic acid derivatives and other glucosides specifically, pro-anthocyanidin trimer and procyanidin-B 1 (dimer) were indentified in completely colored rice cultivars. Higher DPPH radical scavenging activity of pigmented cultivars was due to higher percentage of phenolics like thymol, quinicquinic-caffeicacid ester and polar dicaffeoylquinic acid; whereas higher lipid peroxidation inhibition was attributed to the presence of polar substances such as p-hydroxybenzoicacid, procyanidin B 1 and quercetin-3 -O- rutinoside. The phosphomolybdenum reduction capacity was attributed to luteolin-7- O- glucoside, apigenin-7- O- glucoside, caffeicacid, myrecitin and phloreticacid. Whereas, grater reducing power of pigmented bran was attributed to presence of multiple-OH groups containing phenols, flavonoid and hydracinammicacid depicting potential health and nutritional effects of these rice cultivars. [ABSTRACT FROM AUTHOR]

Abstract: A solution of N-vinyl imidazole (VIm), ethylene glycol dimethylacrylate (EGDMA), and phloretic acid (p-hydroxyphenylpropionic acid, HPPA) as functional monomer, crosslinker and template, respectively, were used to graft molecularly imprinted polymer (MIP) onto polyethylene/polypropylene (PE/PP) nonwoven fabric via gamma radiation at room temperature. Control grafted films were also synthesized using the same procedure in the absence of HPPA. Binding performance of the MIP grafts was investigated for different template molecule concentrations and contact time. An imprinting factor for the sample prepared at 5kGy dose was determined as 2.41 for 50ppm HPPA solution for 3-h incubation. MIP graft layers were investigated by positron annihilation lifetime spectroscopy (PALS) as well as SEM. [Copyright &y& Elsevier]

• Engineered E. coli produced highest titer of phloretic acid from glucose. • A novel functional 4CL facilitated the biosynthesis of phloretin in E. coli. • Structure-guiding mutagenesis of MdCHS3 increased the production of phloretin. • Phloretin was effieciently bioconverted to phlorizin. Phloretic acid, phloretin and phlorizin (phloretin 2′-O-glucoside), plant-derived natural products, are well known for human health benefits and medical application. Here, we construct an artificial biosynthetic pathway of phlorizin by modular engineering strategy and realize the production of phloretic acid, phloretin and phlorizin in Escherichia coli. Extending from L-tyrosine biosynthetic pathway, we firstly established the phloretic acid module comprised of heterologous TAL and ER enzymes, and highest titer of phloretic acid was achieved from glucose. Then, through biochemical screening of functional microbial Aa4CL and structure-based mutagenesis of MdCHS3 in phloretin module, we successfully constructed the phloretin biosynthetic pathway. Finally, we tested several glycosyltransferases in phlorizin module, and phloretic acid was bioconverted to phlorizin. This is the first report on biosynthesis of phloretin and phlorizin in engineered E. coli , indicating the promising potential of microbial cell factories to produce natural and unnatural dihydrochalcones. [ABSTRACT FROM AUTHOR]

Abstract: Dihydro-p-coumaric (phloretic) and dihydroferulic acids have been identified in Pteridium aquilinum. Whereas the latter has been located in cyanogenic and acyanogenic plants, the first has only been detected in cyanogenic forms. [Copyright &y& Elsevier]