Although discarded as waste, shrimp heads are a potential source of antifreeze peptides, which can be used as cryoprotectants in the food industry. Their utilization in frozen foods can help mitigate the negative effects caused by the freezing technique. Litopenaeus vannamei shrimp heads were autolyzed, and the shrimp head autolysate (SHA) was separated via ultra-filtration and ion exchange chromatography. The antifreeze effect of SHA on the biochemical properties of myofibrillar proteins of peeled shrimps during five freeze-thaw cycles was evaluated. Peptide screening was done using the LC-MS/MS technique. A molecular docking (MD) study of the interaction between ice and shrimp head-derived antifreeze peptides was done. Results showed that shrimp-head autolysate has a maximum thermal hysteresis value of 1.84 °C. During the freeze-thaw cycles, the shrimp-head autolysate exhibited an antifreeze effect on frozen peeled shrimps. 1.0 and 3.0%-SHA groups showed significantly lower freeze denaturation than the negative control group. The muscle tissues of SHA-treated groups were not as severely damaged as the negative control group. The molecular docking study revealed that the shrimp head-AFPs bound to ice via hydrogen bonding, and both hydrophilic and hydrophobic amino acid residues were involved in the ice-binding interactions. 6 ice-binding sites were involved in the peptide-ice interaction. Our findings suggest that shrimp head-derived AFPs can be developed into functional additives in frozen foods and add more insights into the existing literature on antifreeze peptides.

2017-06-01·Complementary Therapies in Medicine4区 · 医学

The effects of Gua sha on symptoms and inflammatory biomarkers associated with chronic low back pain: A randomized active-controlled crossover pilot study in elderly

4区 · 医学

Article

作者: Tsang, William W N ; Chiang, Vico C L ; Tse, Sonny H M ; Chung, Hilary H Y ; Loo, Wings T Y ; Yuen, John W M ; Choi, Thomas K S ; Chan, Suk-Tak ; Wong, Diana L Y ; Tam, Jacky K K

OBJECTIVETo address the challenges for trialing with elderly and the lacking of valid sham/placebo control, a randomized crossover pilot study is designed and its feasibility on elderly subjects is evaluated.DESIGNA pilot randomized crossover study was conducted with hydrocollator-based hot pack therapy as active control. Pain intensity, physical disability, depression, general health status, and salivary biomarkers were assessed as outcome measures.RESULTSDespite there was no significant difference observed between any outcome measures attained by the two interventions, several important differences were noted during the one-week follow-up period. The magnitudes of pain reduction (21-25% versus 16-18%) and disability improvement (45-52% versus 39-42%) were greater in the Gua sha-treated group than the hot pack group. Both treatments were shown to improve flexion, extension and bending movements of the lower back, whereas areas of improvement varied between the two interventions. Decreasing trends were observed in both tumor necrosis factor-alpha (TNF-α) and heme-oxygenase-1 (HO-1) levels following Gua sha. However, rebounds of the biomarkers were observed one week following hot pack. Furthermore, in response to Gua sha, the decrease of TNF-α was strongly correlated with the improvement of physical disability, whereas the physical disability was correlated with the VAS pain intensity.CONCLUSIONIt demonstrated a feasible clinical trial protocol for evaluating the effectiveness of Gua sha and other therapeutic modalities. Gua sha may exhibit a more long-lasting anti-inflammatory effect relative to hot pack for pain relief and improved mobility in elderly patients with chronic low back pain.

100 项与 Sulfated hyaluronic acid 相关的药物交易

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