Search

Cardiac arterial bulbs of Skipjack tuna (Katsuwonus pelamis) are rich in elastin, and its hydrolysates are high quality raw materials for daily cosmetics. In order to effectively utilizing Skipjack tuna processing byproducts-cardiac arterial bulbs and to prepare peptides with high antioxidant activity, pepsin was selected from six proteases for hydrolyzing proteins, and the best hydrolysis conditions of pepsin were optimized. Using ultrafiltration and chromatographic methods, eleven antioxidant peptides were purified from protein hydrolysate of tuna cardiac arterial bulbs. Four tripeptides (QGD, PKK, GPQ and GLN) were identified as well as seven pentapeptides (GEQSN, GEEGD, YEGGD, GEGER, GEGQR, GPGLM and GDRGD). Three out of them, namely the tripeptide PKK and the pentapeptides YEGGD and GPGLM exhibited the highest radical scavenging activities on 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl, 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and superoxide anion assays. They also showed to protect plasmid DNA and HepG2 cells against H2O2-induced oxidative stress. Furthermore, they exhibited high stability under temperature ranged from 20-100 °C, pH values ranged from 3-11, and they simulated gastrointestinal digestion for 240 min. These results suggest that the prepared eleven antioxidant peptides from cardiac arterial bulbs, especially the three peptides PKK, YEGGD, and GPGLM, could serve as promising candidates in health-promoting products due to their high antioxidant activity and their stability.

In this paper, remodeling the shrimp processing chain and the effects of the transformation on the biochemical and sensory qualities of fresh Pacific white shrimp (

In the work, defatted muscle proteins of monkfish (Lophius litulon) were separately hydrolyzed by pepsin, trypsin, and in vitro gastrointestinal (GI) digestion methods, and antioxidant peptides were isolated from proteins hydrolysate of monkfish muscle using ultrafiltration and chromatography processes. The antioxidant activities of isolated peptides were evaluated using radical scavenging and lipid peroxidation assays and H2O2-induced model of HepG2 cells. In which, the cell viability, reactive oxygen species (ROS) content, and antioxidant enzymes and malondialdehyde (MDA) levels were measured for evaluating the protective extent on HepG2 cells damaged by H2O2. The results indicated that the hydrolysate (MPTH) prepared using in vitro GI digestion method showed the highest degree of hydrolysis (27.24 ± 1.57%) and scavenging activity on a 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical (44.54 ± 3.12%) and hydroxyl radical (41.32 ± 2.73%) at the concentration of 5 mg protein/mL among the three hydrolysates. Subsequently, thirteen antioxidant peptides (MMP-1 to MMP-13) were isolated from MPTH. According to their DPPH radical and hydroxyl radical scavenging activity, three peptides with the highest antioxidant activity were selected and identified as EDIVCW (MMP-4), MEPVW (MMP-7), and YWDAW (MMP-12) with molecular weights of 763.82, 660.75, and 739.75 Da, respectively. EDIVCW, MEPVW, and YWDAW showed high scavenging activities on DPPH radical (EC50 0.39, 0.62, and 0.51 mg/mL, respectively), hydroxyl radical (EC50 0.61, 0.38, and 0.32 mg/mL, respectively), and superoxide anion radical (EC50 0.76, 0.94, 0.48 mg/mL, respectively). EDIVCW and YWDAW showed equivalent inhibiting ability on lipid peroxidation with glutathione in the linoleic acid model system. Moreover, EDIVCW, MEPVW, and YWDAW had no cytotoxicity to HepG2 cells at the concentration of 100.0 µM and could concentration-dependently protect HepG2 cells from H2O2-induced oxidative damage through decreasing the levels of reactive oxygen species (ROS) and MDA and activating intracellular antioxidant enzymes of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px). These present results indicated that the protein hydrolysate and isolated antioxidant peptides from monkfish muscle, especially YWDAW could serve as powerful antioxidants applied in the treatment of some liver diseases and healthcare products associated with oxidative stress.

// Bo-Hua Su 1,* , Jing Qu 1,* , Min Song 1,* , Xiao-Yu Huang 1 , Xiao-Meng Hu 1 , Jian Xie 1 , Yong Zhao 2 , Lin-Can Ding 1 , Lin She 1 , Jiang Chen 3 , Li-Song Lin 4 , Xu Lin 5 , Da-Li Zheng 5,6 and You-Guang Lu 1 1 Department of Preventive Dentistry, Affiliated Stomatological Hospital, Fujian Medical University, Fuzhou, China 2 Department of Pathology, Affiliated Stomatological Hospital, Fujian Medical University, Fuzhou, China 3 Center of Dental Implant, Affiliated Stomatological Hospital, Fujian Medical University, Fuzhou, China 4 Department of Oral and Maxillofacial Surgery, Affiliated First Hospital of Fujian Medical University, Fuzhou, China 5 Key Laboratory of Ministry of Education for Gastrointestinal Cancer, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, China 6 Molecular Oncology, Moffitt Cancer Center, Tampa, FL, United States * These authors contributed equally to this work Correspondence: Da-Li Zheng, email: // You-Guang Lu, email: // Keywords : NOTCH1, salivary adenoid cystic carcinoma, proliferation, apoptosis, metastasis Received : July 07, 2014 Accepted : August 05, 2014 Published : August 06, 2014 Abstract Background: Numerous studies have reported both the tumor-suppressive and oncogenic roles of the Notch pathway, indicating that Notch activity regulates tumor biology in a complex, context-dependent manner. The aim of the present study was to identify the role of NOTCH1 in the cell growth and metastasis of SACC. Methods: We analyzed the expression of NOTCH1 in clinical SACC samples using immunohistochemical staining. We silenced the expression of NOTCH1 and overexpressed activated NOTCH1 to elucidate the effects of NOTCH1 on proliferation, migration and invasion. NOTCH1 target genes were validated by real-time PCR. Results: Our results showed that NOTCH1 was upregulated in SACC tissues when compared with normal tissues, and this upregulation was further enhanced in SACC tissues with metastasis and recurrence when compared with SACC tissues without metastasis. Overexpression of NOTCH1 in SACC cells promoted cell growth, migration and invasion, and knockdown of NOTCH1 inhibited cell proliferation in vitro and tumorigenicity in vivo by inducing cell apoptosis. Conclusions:The results of this study suggest that NOTCH1 plays a key role in the cell growth, anti-apoptosis, and metastasis of SACC. NOTCH1 inhibitors might therefore have potential therapeutic applications in treating SACC patients by inhibiting cancer cell growth and metastasis.