Effect of colocasia leaves (Colocasia antiquorum) on serum and tissue lipids in cholesterol-fed rats

Dried colocasia powder (10% and 20%) was fed to hypercholesterolemic rats for a period of one month to explore the effect on serum lipids and tissue lipids. The results indicated that there was a significant increase in total lipids, total cholesterol, and triglycerides levels in the cholesterol fed rats. Liver cholesterol showed a slight reduction which was non-significant, while an increase in liver triglyceride was observed in rats fed with 10% and 20% colocasia leaves diet with or without cholesterol. All these observations indicate an aggravating effect of colocasia leaves on serum and tissue lipids in cholesterol-fed rats.     

Influence of sulfur-amino acid content variation in plant vs animal protein on serum and tissue lipids in rats

The objective of the study was to determine the effects of methionine and cysteine supplementation of soy protein isolate and casein on serum and tissue lipid levels in rats. Sixty male, weanling, Wistar-Kyoto rats were fed two sources of protein (casein or soy protein isolate) and three variations of sulfur-amino acid supplementation (none, methionine, or cysteine). At this level of protein intake (10% by weight), rats fed soy-based diets had similar serum lipid concentrations than rats fed casein-based diets. Choline was not added to the diet in order to be able to assess independent influences of methionine and cysteine on lipid metabolism. Overall, serum lipid values were greater in rats fed proteins supplemented with methionine while the addition of cysteine produced lower lipid levels. Liver lipid concentrations were increased tremendously upon cysteine supplementation of soy protein isolate. Protein quality, as determined by protein efficiency ratio, was improved by supplementation of either sulfur-amino acid; however, methionine had the greatest effect. Results indicate that the sulfur-amino acids influence lipid metabolism in the absence of dietary choline. The mechanism by which this occurs is not known.     

鳗鲡脂肪酸组成和胆固醇含量分析

对日本鳗鲡（Anguilla japonica）、欧洲鳗鲡（Anguilla anguilla）及其制品烤鳗进行胆固醇、脂肪含量和脂肪酸组成分析。结果表明，鳗鲡的胆固醇含量与其他鱼类接近，日本鳗鲡和欧洲鳗鲡及其烤鳗制品的胆固醇质量比分别为0.852、0.832mg/g和1.15、1.12mg/g。鳗鲡各食用部位中除腹部的胆固醇较高外，其他部位没有明显差异。鳗鲡的脂肪质量分数16％-24％，日本鳗鲡和欧洲鳗鲡高度不饱和脂肪酸质量分数分别为18.9％和19.0％，EPA DHA质量比分别为22.66mg/g和29.27mg/g。     

Effect of dietary supplementation with fermented Ginkgo-leaves on performance,egg quality,lipid metabolism and egg-yolk fatty acids composition in laying hens

The present study was conducted to investigate the effect of 3 types of fermented Ginkgo-leaves (FGL) on layer performance, egg quality, lipid metabolism, microbial populations, and egg-yolk fatty acids composition in laying hens. A total of 432 Lohmann Brown laying hens, 49 weeks of age, were randomly allocated to 4 dietary treatments with 6 replications of 18 birds each. Layers were fed basal diets (Control) or basal diets supplemented with 0.5% Ginkgo-leaves fermented with Candida utilis (CF group), Aspergillus niger (AF group), or their combined fermentation (CAF group), respectively, for an 8-week feeding trial. Compared with the control group, AF and CAF supplementation improved (P<0.05) laying rate and feed conversion ratio. Birds fed FGL (CF, AF and CAF) supplemented diet had a decrease (P<0.05) in cracked-egg rate, egg-yolk cholesterol, serum total cholesterol, triglyceride and low density lipoprotein cholesterol levels, while serum high density lipoprotein cholesterol concentrations of birds from CF and AF groups were increased (P<0.05) compared with that of the control. The concentrations of C18:1 (n-9), C18:2 (n-6), total polyunsaturated fatty acids (PUFA), ratio of PUFA/saturated fatty acids (SFA) and n-6: n-3 was increased (P<0.05 or P<0.01) with FGL supplementation. While FGL supplementation led to a decrease in total saturated fatty acids (P=0.01) concentrations. In addition, ileal and cecum Lactobacilli and Bifidobacteria populations of birds fed FGL were increased (P<0.05) compared with the control group, while ileal Escherichia coli, Salmonellas, and cecal Salmonellas were decreased in birds fed FGL. In conclusion, dietary supplementation of FGL, especially AF and CAF, in layer diets may be a feasible means of producing eggs with lower cholesterol and higher PUFA contents for health conscious consumers.     

Anti-Microbial,Anti-Biofilm Activities and Cell Selectivity of the NRC-16 Peptide Derived from Witch Flounder,Glyptocephalus cynoglossus

Previous studies had identified novel antimicrobial peptides derived from witch flounder. In this work, we extended the search for the activity of peptide that showed antibacterial activity on clinically isolated bacterial cells and bacterial biofilm. Pseudomonas aeruginosa was obtained from otitis media and cholelithiasis patients, while Staphylococcus aureus was isolated from otitis media patients. We found that synthetic peptide NRC-16 displays antimicrobial activity and is not sensitive to salt during its bactericidal activity. Interestingly, this peptide also led to significant inhibition of biofilm formation at a concentration of 4–16 μM. NRC-16 peptide is able to block biofilm formation at concentrations just above its minimum inhibitory concentration while conventional antibiotics did not inhibit the biofilm formation except ciprofloxacin and piperacillin. It did not cause significant lysis of human RBC, and is not cytotoxic to HaCaT cells and RAW264.7 cells, thereby indicating its selective antimicrobial activity. In addition, the peptide’s binding and permeation activities were assessed by tryptophan fluorescence, calcein leakage and circular dichroism using model mammalian membranes composed of phosphatidylcholine (PC), PC/cholesterol (CH) and PC/sphingomyelin (SM). These experiments confirmed that NRC-16 does not interact with any of the liposomes but the control peptide melittin did. Taken together, we found that NRC-16 has potent antimicrobial and antibiofilm activities with less cytotoxicity, and thus can be considered for treatment of microbial infection in the future.     

Prospects of Marine Sterols against Pathobiology of Alzheimer’s Disease: Pharmacological Insights and Technological Advances

Alzheimer’s disease (AD) is a degenerative brain disorder characterized by a progressive decline in memory and cognition, mostly affecting the elderly. Numerous functional bioactives have been reported in marine organisms, and anti-Alzheimer’s agents derived from marine resources have gained attention as a promising approach to treat AD pathogenesis. Marine sterols have been investigated for several health benefits, including anti-cancer, anti-obesity, anti-diabetes, anti-aging, and anti-Alzheimer’s activities, owing to their anti-inflammatory and antioxidant properties. Marine sterols interact with various proteins and enzymes participating via diverse cellular systems such as apoptosis, the antioxidant defense system, immune response, and cholesterol homeostasis. Here, we briefly overview the potential of marine sterols against the pathology of AD and provide an insight into their pharmacological mechanisms. We also highlight technological advances that may lead to the potential application of marine sterols in the prevention and therapy of AD.     

Effectiveness of Chitosan as a Dietary Supplement in Lowering Cholesterol in Murine Models: A Meta-Analysis

This study presents a meta-analysis of studies that investigate the effectiveness of chitosan administration on lifestyle-related disease in murine models. A total of 34 published studies were used to evaluate the effect of chitosan supplementation. The effect sizes for various items after chitosan administration were evaluated using the standardized mean difference. Using Cochran’s Q test, the heterogeneity of effect sizes was assessed, after which a meta-ANOVA and -regression test was conducted to explain the heterogeneity of effect sizes using the mixed-effect model. Publication bias was performed using Egger’s linear regression test. Among the items evaluated, blood triglyceride and HDL-cholesterol showed the highest heterogeneity, respectively. Other than blood HDL-cholesterol, total cholesterol, and triglyceride in feces, most items evaluated showed a negative effect size with high significance in the fixed- and random-effect model (p < 0.0001). In the meta-ANOVA and -regression test, administering chitosan and resistant starch was revealed to be most effective in lowering body weight. In addition, chitosan supplementation proved to be an effective solution for serum TNF-α inhibition. In conclusion, chitosan has been shown to be somewhat useful in improving symptoms of lifestyle-related disease. Although there are some limitations in the results of this meta-analysis due to the limited number of animal experiments conducted, chitosan administration nevertheless shows promise in reducing the risk of cholesterol related metabolic disorder.     

24(S)-Saringosterol Prevents Cognitive Decline in a Mouse Model for Alzheimer’s Disease

We recently found that dietary supplementation with the seaweed Sargassum fusiforme, containing the preferential LXRβ-agonist 24(S)-saringosterol, prevented memory decline and reduced amyloid-β (Aβ) deposition in an Alzheimer’s disease (AD) mouse model without inducing hepatic steatosis. Here, we examined the effects of 24(S)-saringosterol as a food additive on cognition and neuropathology in AD mice. Six-month-old male APPswePS1ΔE9 mice and wildtype C57BL/6J littermates received 24(S)-saringosterol (0.5 mg/25 g body weight/day) (APPswePS1ΔE9 n = 20; C57BL/6J n = 19) or vehicle (APPswePS1ΔE9 n = 17; C57BL/6J n = 19) for 10 weeks. Cognition was assessed using object recognition and object location tasks. Sterols were analyzed by gas chromatography/mass spectrometry, Aβ and inflammatory markers by immunohistochemistry, and gene expression by quantitative real-time PCR. Hepatic lipids were quantified after Oil-Red-O staining. Administration of 24(S)-saringosterol prevented cognitive decline in APPswePS1ΔE9 mice without affecting the Aβ plaque load. Moreover, 24(S)-saringosterol prevented the increase in the inflammatory marker Iba1 in the cortex of APPswePS1ΔE9 mice (p < 0.001). Furthermore, 24(S)-saringosterol did not affect the expression of lipid metabolism-related LXR-response genes in the hippocampus nor the hepatic neutral lipid content. Thus, administration of 24(S)-saringosterol prevented cognitive decline in APPswePS1ΔE9 mice independent of effects on Aβ load and without adverse effects on liver fat content. The anti-inflammatory effects of 24(S)-saringosterol may contribute to the prevention of cognitive decline.     

类芽孢杆菌胞外胆固醇氧化酶的分离纯化

[目的]探讨类芽孢杆菌产生胞外胆固醇氧化酶(COD)的分离、纯化方法,为其生产和应用提供技术支持.[方法]将类芽孢杆菌发酵液通过旋转蒸发浓缩、蔗糖透析浓缩、DEAE离子交换柱层析和凝胶层析,纯化目的蛋白,然后测定获得酶的基本酶学性质.[结果]类芽孢杆菌发酵液经DEAE离子交换柱层析和SephadexG-75凝胶柱层析后,纯化所得的COD比活力达6.83U/mg,酶活力回收为35.6%,纯化倍数为13.4倍.纯化酶经SDS-PAGE显示为均一条带,分子量约58 kDa.将纯化的COD作用于不同浓度胆固醇,采用Lineweaver Burk作图法,测得其Km=3.3×10-5 mol/L.薄层层析结果显示,产物为胆甾-4-烯-3-酮,说明纯化所得酶是COD.[结论]纯化获得电泳纯类的芽孢杆菌胞外COD,其与底物亲和力较强,具有潜在的应用研究价值.     

Nutrient Composition of Raw and Cooked Meat of Male Southern King Crab (Lithodes santolla Molina, 1782)

This study provides information about nutrient composition of adult males of southern king crab (Lithodes santolla). Proximate composition of raw and cooked meat (g/100 g meat) averaged: moisture?=?80.9 and 78.6, protein?=?14.6 and 16.3, fat?=?0.70 and 0.76, and ash?=?2.03 and 2.10, respectively. Arginine, glutamic acid, leucine, and aspartic acid (20.4, 9.4, 8.0, and 7.9 g aa/100 g protein, respectively) were the major amino acids. The predominant fatty acid was 18:1n-9c (21.8 and 22.1%), followed by 20:5n-3 (17.1 and 21.8%), 16:0 (15.8 and 15.3%), and 22:6n-3 (11.0 and 13.5%). Cooked meat contained more cholesterol (51.0 mg/100 g meat) and phospholipids (60.1 mg/100 g meat) than raw meat (37.3 and 13.9 mg/100 g meat, respectively), with phosphatidylcholine representing over 80% of the total phospholipid content. The main tocopherol was α-tocopherol (raw meat?=?1.30 mg/100 g meat, cooked meat?=?1.14 mg/100 g meat). Major mineral contents of raw and cooked meat (mg/100 g meat) were: Na?=?509 and 594, K?=?179 and 203, Ca?=?114 and 197, P?=?126 and 143, Mg?=?34 and 41, Fe?=?1.26 and 1.86, and Zn?=?1.88 and 2.64, respectively. Thus, the nutritional quality of the cooked meat of the southern king crab makes it especially adequate for cholesterol-restricted, balanced low-fat meat diets.