Effects of Sheep Bone Collagen Peptide on Liver Lipid Deposition in Ovariectomized Rats.

Liver can be directly involved in the synthesis and decomposition of fatty acids. Liver lipid deposition is one of the most common chronic liver diseases. Estrogen deficiency can cause lipid deposition and energy metabolism disorders in the liver. Sheep bone collagen peptide (SBCP) has been shown to have estrogen-like effects in previous studies. And SBCP has high bioavailability, safety and non-toxic side effects. This study aimed to investigate the effect of SBCP on liver lipid deposition (LLD) caused by estrogen deficiency. Female Wistar rats were treated as follows (n=10): sham group: underwent peri-ovary fat removal operations, ovariectomized rats (model group), ovariectomized rats receiving SBCP treatments: SBCP high dose group (SBCP-H), SBCP medium dose group (SBCP-M) and SBCP low dose group (SBCP-L). After 8 wk, the model group demonstrated severe LLD and liver pathological changes, with increased malondialdehyde (MDA) and free fatty acid (FFA) levels (p<0.05). Additionally, the total superoxide dismutase (T-SOD) activity (p<0.05), serum albumin-to-globulin (A/G) ratio (p<0.05), amount of butyric acid-producing bacteria and short-chain fatty acids (SCFAs) content decreased. SBCP intervention could inhibit the occurrence of LLD and alleviate the liver histopathological damage induced by estrogen deficiency by relieving oxidative stress, preventing the loss of butyric acid-producing bacteria, and decreasing the abundance of Lactobacillus reuteri in the gut. The results suggested that SBCP could improve the LLD indecued by estrogen deficiency.

Multi-Residue Analysis of Fipronil and Its Metabolites in Eggs by SinChERS-Based UHPLC-MS/MS.

A method for simultaneous detection of fipronil (F) and its metabolites fipronil desulfinyl (FD), fipronil sulfide (FS), fipronil sulfone (FSO) in chicken eggs was applied and validated. It includes single-step, cheap, effective, rugged, safe-based method (SinChERS) for sample preparation and ultra high performance liquid chromatography coupled with mass spectrometry (UHPLC-MS/MS) for chemical analysis. Results suggested that formic acid enhanced the recovery of 4 target residues and 1% supplementation to acetonitrile gained higher recoveries than that of 5%. SinChERS integrated extraction and clean-up steps into one, with shorter time (1.5 h) to operate and higher recoveries (97%-100%) than HLB, Envi-Carb-NH2 and quik-easy-cheap-effective-rugged-safe method (QuEChERS), and it consumed the smallest volume of extracting solvent (10 mL) as QuEChERS. Quantitative analyses using external standard method suggested the linear ranges of 4 target compounds were 1-20 µg/L with R2>0.9947. The limit of detection (S/N>3) and quantification (S/N>10) were 0.3 µg/kg and 1 µg/kg. Recoveries ranged from 89.0% to 104.4%, and the relative standard deviations (n=6) at 1, 10, and 20 µg/kg were lower than 6.03%. Thirty batches of domestic eggs (500 g each) were detected by the established SinChERS-based UHPLC-MS/MS and no target residues were detected in all samples. The method developed in this study is a rapid, sensitive, accurate and economic way for multi-residue analysis of fipronil and its metabolites in eggs.

[Fermentation of sheep bone enzymatic hydrolysates by Lactobacillus plantarum].

In order to improve the nutritional value and bio-availability of sheep bone enzymatic hydrolysates, we tried to ferment the hydrolysates with lactic acid bacteria (LAB) to enhance free Ca²âº, to generate oligopeptide and antioxidative activity. First, we isolated 7 LAB strains from commercial starters and selected Lactobacillus plantarum as the starter for its highest protease-producing ability. The content of released Ca²âº was evaluated when the fermenting conditions were optimized by the method of responsive surface design. When supplemented with 1% maltose and inoculated 4% L. plantarum, at initial pH 5.5 and 37 ℃ for 14 h, Ca²âº content in the hydrolysates increased significantly (P<0.05), as well as the generation oligopeptide (P<0.01), and the content of hydroxyproline (P<0.01). The count of L. plantarum in the fermented hydrolysates reached to 94.6×108 CFU/mL. L. plantarum fermentation significantly enhanced the ability to scavenge free radicals DPPH, ·OH and O2⁻· (P<0.01, P<0.05). Therefore, fermenting sheep bone hydrolysates by L. plantarum can increase free Ca²âº, oligopeptide and antioxidative ability.

Effects of Lactobacillus helveticus Fermentation on the Ca2+ Release and Antioxidative Properties of Sheep Bone Hydrolysate.

Both the calcium and collagen in bone powder are hard to be absorbed by the body. Although enzymatic hydrolysis by protease increased the bio-availability of bone powder, it was a meaningful try to further increase Ca2+ release, oligopeptide formation and antioxidant activity of the sheep bone hydrolysate (SBH) by lactic acid bacteria (LAB) fermentation. Lactobacillus helveticus was selected as the starter for its highest protease-producing ability among 5 tested LAB strains. The content of liberated Ca2+ was measured as the responsive value in the response surface methodology (RSM) for optimizing the fermenting parameters. When SBH (adjusted to pH 6.1) supplemented with 1.0% glucose was inoculated 3.0% L. helveticus and incubated for 29.4 h at 36℃, Ca2+ content in the fermented SBH significantly increased (p<0.01), and so did the degree of hydrolysis and the obtaining rate of oligopeptide. The viable counts of L. helveticus reached to 1.1×1010 CFU/mL. Results of Pearson correlation analysis demonstrated that LAB viable counts, Ca2+ levels, obtaining rates of oligopeptide and the yield of polypeptide were positively correlated with each other (p<0.01). The abilities of SBH to scavenge the free radicals of DPPH, OH and ABTS were also markedly enhanced after fermentation. In conclusion, L. helveticus fermentation can further boost the release of free Ca2+ and oligopeptide, enhance the antioxidant ability of SBH. The L. helveticus fermented SBH can be developed as a novel functional dietary supplement product.