The impacts of fermented feed on laying performance, egg quality, immune function, intestinal morphology and microbiota of laying hens in the late laying cycle.

Fermented feed has the potential to improve poultry gastrointestinal microecological environment, health condition and production performance. Thus, the present study was undertaken to explore the effects of fermented feed on the laying performance, egg quality, immune function, intestinal morphology and microbiota of laying hens in the late laying cycle. A total of 360 healthy Hy-Line Brown laying hens aged 80 weeks were used to conduct a 56-day study. All hens were randomly separated into two treatment groups, with five replicates of 36 hens each as follows: basal diet containing 0.0% fermented feed (CON) and 20% fermented feed (FF). Subsequent analyses revealed that fermented feed supplementation was associated with significant increases in laying rates together with reduced broken egg rates and feed conversion ratio for hens in FF group (P < 0.05). There were additionally significant increases in both albumen height and Haugh unit values in hens following fermented feed supplementation (P < 0.05). Fermented feed was also associated with increases in duodenal, jejunal and ileac villus height (P < 0.05). Laying hens fed fermented feed had higher immune globulin (Ig)A, IgG, IgM levels (P < 0.01,) and higher interleukin 2, interleukin 6, tumour necrosis factor α and interferon γ (P < 0.05) concentrations than CON. Analysis of the microbiota in these laying hens revealed the alpha diversity was not significantly affected by fermented feed supplementation. Firmicutes abundance was reduced in caecal samples from FF hens relative to those from CON hens (30.61 vs 35.12%, P < 0.05). At the genus level, fermented feed was associated with improvements in relative Lactobacillus, Megasphaera and Peptococcus abundance and decreased Campylobacter abundance in laying hens. These results suggest that fermented feed supplementation may be beneficial to the laying performance, egg quality, immunological function, intestinal villus growth and caecal microecological environment of laying hens at the end of the laying cycle.

[Degradation of lignocellulose in the corn straw by Bacillus amyloliquefaciens MN-8].

Microbial degradation of lignocellulose is one of the key problems that need to be solved urgently in the process of utilizing biomass resource. Bacillus amyloliquefaciens MN-8 is our previously isolated bacterium capable of degrading lignin. To determine the capability of strain MN-8 to degrade lignocellulose of corn straw, B. amyloliquefaciens MN-8 was inoculated and fermented with solid-state corn straw powder-MSM culture medium. The changes in the enzyme activity and degradation products of lignocellulose were monitored in the process of fermentation using the FTIR and GC/MS. The results showed that B. amyloliquefaciens MN-8 could produce lignin peroxidase, manganese peroxidase, cellulase and hemicellulase enzymes. The activities of all these enzymes reached the peak after being incubated for 10-16 days, and the highest enzyme activities were 55.0, 16.7, 45.4 and 60.5 U · g(-1), respectively. After 24 d of incubation, the degradation percentages of lignin, cellulose and hemicellulose were up to 42.9%, 40.6% and 27.1%, respectively. The spectroscopic data by FTIR indicated that the intensities of characteristic absorption peaks of lignin, cellulose and hemicellulose of the corn straw were decreased, indicating that the lignocellulose was degraded partly after being fermented by B. amyloliquefaciens MN-8. GC/MS analysis also demonstrated that strain MN-8 could degrade lignocellulose efficiently. It could depolymerize lignin into some monomeric compounds with retention of phenylpropane structure unit, such as amphetamine, benzene acetone and benzene propanoic acids, by the rupture of ß-O-4 bond connected between lignin monomer, and it further oxidized some monomer compounds into Cα carbonyl compounds, such as 2-amino-1-benzeneacetone and 4-hydroxy-3,5-dimethoxy-acetophenone. The GC/MS analysis of the degradation products of cellulose and hemicellulose showed that there were not only monosaccharide compounds, such as glucose, mannose and galactose, but also some glycolysis products including formic acid, acetic acid, propionic acid, 1,1-ethanediol and 3-hydroxy butyric acid. Our results demonstrated that B. amyloliquefaciens MN-8 is capable of degrading lignocelluse of the corn straw effectively and the degradation capacity depends on the lignocellulase activity.

Pharmacological characterisation of spider antimicrobial peptides.

Most spider antimicrobial peptides share a common mechanism of membrane permeabilisation and the innate immune systems of the pathogen. In this review, we present recent accounts of the application at the preclinical level that should be tried and the range of bioactivities and their particular structure can be harnessed for molecular engineering applications and in drug design. Structural analyses such as amino acid sequence and circular dichroism are described. Conductance measurements and pharmacological studies of the action on the inner or outer membranes of anti-microbe will reveal more about the mode of action of the antimicrobial peptides of spider.

[Inhibitory effect of the venom of spider Macrothele raveni on proliferation of human hepatocellular carcinoma cell line BEL-7402 and its mechanism].

BACKGROUND & OBJECTIVE: Antitumor effect of spider venom has not been reported yet. This study was to explore inhibitory effect of the venom of spider Macrothele raveni on proliferation of human hepatocellular carcinoma cell line BEL-7402 and its molecular mechanism. METHODS: When treated with the venom of spider Macrothele raveni, proliferation of BEL-7402 cells was examined by MTT assay; DNA synthesis of BEL-7402 cells was tested by 3H-TdR incorporation; cell apoptosis and cell cycle were detected by flow cytometry; expression of C-myc was detected by Western blot. RESULTS: The spider venom inhibited proliferation of BEL-7402 cells in time-dependent and concentration-dependent manners with 50% inhibitory concentration (IC(50)) of 20 microg/ml (48 h), and inhibited DNA synthesis of BEL-7402 cells. After treatment of the spider venom, apoptosis of BEL-7402 cells was enhanced, and cells were arrested in G(0)/G(1) phase; expression of C-myc was obviously down-regulated. CONCLUSION: The venom of spider Macrothele raveni could inhibit proliferation and DNA synthesis of BEL-7402 cells, which might through inducing cell apoptosis, down-regulating C-myc, and arresting cell cycle progression of BEL-7402 cells.

Effects of spider Macrothele raven venom on cell proliferation and cytotoxicity in HeLa cells.

AIM: To examine the effect of venom from the spider Macrothele raven on cell proliferation and cytotoxicity in human cervical carcinoma, HeLa cells. METHODS: Morphological and biochemical signs of apoptosis appeared using acridine orange-ethidium bromide (AO/EB) staining. Marked morphological changes in HeLa cells after treatment with spider venom were observed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Cell proliferation and cytotoxicity were determined by [methyl-3H] thymidine assay ([3H]TdR) and lactate dehydrogenase (LDH) release, respectively. DNA fragmentation and cell cycle distribution were monitored using flow cytometry. In addition, Western blot analysis was used to evaluate the level of caspase-3 expression. In vivo examination of the inhibition of the size of tumors in nude mice treated with spider venom was measured. RESULTS: Marked morphological changes were observed using AO/EB staining, SEM and TEM assay. Spider venom at concentrations of 10-40 mg/L caused dose- and time-dependent inhibition of HeLa cell proliferation. The ratio of apoptosis and necrosis increased. The activity of caspase-3 was upregulated after spider venom treatment. In vivo study of tumor size revealed that tumors significantly decreased in size from controls to tumors treated for 3 weeks with spider venom (P<0.05). CONCLUSION: The inhibition of HeLa cells by the venom of the spider Macrothele raveni was carried out in three ways: induction of apoptosis, necrosis of toxicity damage and direct lysis. Spider venom is a novel anti-tumor material both in vitro and in vivo.