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This study examined the beneficial effects of porphyran from Porphyra haitanensis (PHP) on intestinal epithelial cells, in terms of cell proliferation and migration and elucidated the potential molecular mechanism of action of PHP. Purified PHP is a homogenous polysaccharide with a molecular weight of 2.01 × 10 5  Da, intrinsic viscosity [η] of 463.76 mL/g, and radius of gyration of 61.2 nm. When the intestinal epithelial wound healing activity of PHP was investigated in vitro using the IEC-6 cell line (intestinal epithelial cells-6), it was found that PHP could promote cell migration and proliferation. PHP enhanced the protein expression of cell division control protein 42, paxillin, and focal adhesion kinase, which suggest that PHP might modulate the expression of these proteins to improve intestinal epithelial healing. Thus, this study indicated that PHP could serve as a potential source of functional food constituents for intestinal epithelial protection and restoration., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: Intracerebral hemorrhage (ICH) is a common neurological emergency with higher mortality and disability rate than cerebral ischemia. Although diverse therapeutic interventions have been explored for potential neuroprotection from ICH, no effective drugs until now are available for improvement of survival rate or the life quality of survivors after ICH. Just like cerebral ischemia, inflammatory mechanism is highly thought to play a vital role in hemorrhagic brain injury. Ligustilide (LIG) has potent anti-inflammatory effects, which were shown to be closely related to its neuroprotective effects against ischemic brain injury. Senkyunolide H (SH) and senkyunolide I (SI) are natural degradation products of LIG, which contain the mother nucleus structure of LIG as that of phthalide. However, no reports have been retrieved about the neuroprotective effects of the three phthalide compounds on ICH, especially from the perspectives of inflammatory pathways. Accordingly, this study investigated the neuroprotective potentials and mechanisms of LIG, SH and SI on experimental ICH in mice., Methods: ICH was induced in adult male CD-1 mice by intracerebral injection of autologous blood. LIG, SH and SI, respectively, was administrated after ICH induction. Neurological deficits, brain edema, injury volume, the number of surviving/dying neurons and inflammatory gene expression were evaluated at 3 days after ICH., Results: Neurological deficits, brain edema, neuronal injury, microglia and astrocytes activation as well as peripheral immune cells infiltration were all significantly improved by LIG and SH, yet SI not. Moreover, the expression of TLR4, p-NF-kB p65, TNF-α and IL-6, was significantly downregulated by LIG and SH treatment. So was Prx1 expression and release., Conclusions: LIG and SH provide the potent neuroprotective effects against hemorrhagic stroke by inhibiting Prx1/TLR4/NF-kB signaling and the subsequent immune and neuroinflammation lesions., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A major problem when xylose is used for ethanol production is the intercellular redox imbalance arising from different coenzyme specificities of xylose reductase (XR) and xylitol dehydrogenase. The residue Lys21 in XR from Pichia stipitis was subjected to site-directed mutagenesis to alter its coenzyme specificity. The N272D mutant exhibited improved catalytic efficiency when NADH was the coenzyme. Both K21A and K21A/N272D preferred NADH to NADPH, their catalytic efficiencies for NADPH were almost zero. The catalytic efficiency of K21A/N272D for NADH was almost 9-fold and 2-fold that of K21A and the wild-type enzyme, respectively. Complete reversal of coenzyme specificity toward NADH and improved catalytic efficiency were achieved.