No abstract

Conversion of animal by-products to high value-added food ingredients is one of the top trends in the slaughter industry. Enzymatic hydrolysis of animal by-products can generate protein hydrolysates, which provides an opportunity for effective utilisation. However, bitterness of protein hydrolysate is a major undesirable aspect for various applications. In this review, the current knowledge on protein hydrolysates from animal by-products is briefly reviewed. The structural features of bitter peptides and bitter taste receptors are summarised. Moreover, the potential approaches for debittering protein hydrolysates are highlighted, including exopeptidase treatment, Maillard reaction, plastein reaction and encapsulation. In addition, the current debittering strategies and challenges are also discussed. This article presents some opportunities to utilise protein hydrolysates from animal by-products and their debittering methods.

For enhanced intracellular accumulation of 6-mercaptopurine (6-MP) in leukemia, a folate receptor-targeted and glutathione (GSH)-responsive polymeric prodrug nanoparticle was made. The nanoparticles were prepared by conjugating 6-MP to carboxymethyl chitosan via a GSH-sensitive carbonyl vinyl sulfide linkage, ultrasonic self-assembly and surface decoration with folate. The TEM graphs shows that the as-synthesized nanoparticles are spherical with a particle size of 170~220 nm. In vitro drug release of nanoparticles demonstrated acceptable stability in PBS containing 20 μM GSH at pH 7.4. However, the cumulative drug release rate of the samples containing 20 mM and 10 mM GSH medium reached 78.9% and 64.8%, respectively, in pH 5.0 at 20 h. This indicated that this nano-sized system is highly sensitive to GSH. The inhibition ratio of folate-modified nanoparticles compared to unmodified nanoparticles was higher in cancer cells (human promyelocytic leukemia cells, HL-60) while their cytotoxicity was lower in normal cells (mouse fibroblast cell lines, L929). Furthermore, in vitro cancer cell incubation studies confirmed that folate-modified nanoparticles therapeutics were significantly more effective than unmodified nanoparticles therapeutics. Our results suggest that folate receptor-targeting and GSH-stimulation can significantly elevate tumour intracellular drug release. Therefore, folate-modified nanoparticles containing chemoradiotherapy is a potential treatment for leukemia therapy.

Climate change has resulted in major changes in plant phenology across the globe that includes leaf‐out date and flowering time. The ability of species to respond to climate change, in part, depends on their response to climate as a phenological cue in general. Species that are not phenologically responsive may suffer in the face of continued climate change. Comparative studies of phenology have found phylogeny to be a reliable predictor of mean leaf‐out date and flowering time at both the local and global scales. This is less true for flowering time response (i.e., the correlation between phenological timing and climate factors), while no study to date has explored whether the response of leaf‐out date to climate factors exhibits phylogenetic signal. We used a 52‐year observational phenological dataset for 52 woody species from the Forest Botanical Garden of Heilongjiang Province, China, to test phylogenetic signal in leaf‐out date and flowering time, as well as, the response of these two phenological traits to both temperature and winter precipitation. Leaf‐out date and flowering time were significantly responsive to temperature for most species, advancing, on average, 3.11 and 2.87 day/°C, respectively. Both leaf‐out and flowering, and their responses to temperature exhibited significant phylogenetic signals. The response of leaf‐out date to precipitation exhibited no phylogenetic signal, while flowering time response to precipitation did. Native species tended to have a weaker flowering response to temperature than non‐native species. Earlier leaf‐out species tended to have a greater response to winter precipitation. This study is the first to assess phylogenetic signal of leaf‐out response to climate change, which suggests, that climate change has the potential to shape the plant communities, not only through flowering sensitivity, but also through leaf‐out sensitivity.