Shotgun proteomic analysis of porcine colostrum and mature milk

The epitheliochorial nature of the porcine placenta prevents the transfer of maternal immunity. Therefore, ingestion of the colostrum immediately after birth is crucial for neonatal piglets to acquire passive immunity from the sow. We performed a shotgun proteomic analysis of porcine milk to reveal in detail the protein composition of porcine milk. On the basis of the Swiss‐Prot database, 113 and 118 proteins were identified in the porcine colostrum and mature milk, respectively, and 50 of these proteins were common to both samples. Some immune‐related proteins, including interleukin‐18 (IL‐18), were unique to the colostrum. The IL‐18 concentration in the colostrum and mature milk of four sows was measured to validate the proteomic analysis, and IL‐18 was only detected in the colostrum (191.0 ± 53.9 pg/mL) and not in mature milk. In addition, some proteins involved in primary defense, such as azurocidin, which has never been detected in any other mammal's milk, were also identified in the colostrum.     

Development of myofibrillar ATPase assay system on pH stat

The ATPase assay system on pH stat apparatus was developed. For the ATPase activity measurement, hydrogen ion (H⁺) concentration delivered from inorganic phosphate (Pi) as a hydrolysis production of ATP was estimated by titrating with 20 mM NaOH solution instead of colorimetric measurement of Pi. Inclusion of 0.5 M KCl in the ATP stock solution and 2 mM Tris-maleate (pH 7.0) buffer in the reaction medium reduced the extent of pH change upon addition of ATP to initiate the ATPase reaction. The amount of H⁺ liberated from Pi was strongly affected by the set pH for the ATPase assay with a promotion at alkaline pH. Thus, it was required to estimate the coefficient to convert H⁺ to a Pi concentration at a specific pH. The specified coefficient at pH 7.0 was 1.248. ATPase assay on pH stat allowed us to follow the ATP hydrolysis by myofibrils continuously showing a curvature profile at low salt medium (≤0.2 M KCl) or a linear profile at high salt (≥0.3 M KCl).     

Availability of black soldier fly meal as an alternative protein source to fish meal in red sea bream (Pagrus major,Temminck & Schlegel) fingerling diets

Black soldier fly meal (BM) is an outstanding candidate as a fish meal (FM) substitute because it contains relatively high protein and essential amino acids. In this study, we replaced FM in red sea bream diets (Pagrus major) with BM to investigate its effect on growth and feed utilization. Six isonitrogenous and isolipidic experimental diets were prepared by substituting 0%, 20%, 40%, 60%, 80% and 100% FM protein with BM (Control, BM20, BM40, BM60, BM80 and BM100, respectively). After the 8-week feeding trial, final body weight, weight gain, specific growth rate and feed efficiency decreased linearly with increasing dietary BM level (p < 0.05). Apparent digestibility of protein and fat and serum total cholesterol concentration decreased with increasing dietary BM levels (p < 0.05) Final body weight, WG, SGR and FE against dietary BM level had breaking points of 76.2%, 41.7%, 76.5% and 60.0%, respectively, in segmental regression analysis. In conclusion, the results suggest that BM can replace a maximum of 41.7% of FM in the diet of red sea bream without compromising growth performance or feed efficiency for 56 days.     

Neutralization of Acid Droplets on Plant Leaf Surfaces

Sulfuric acid mist exposure of bush bean leaves at a low rate of precipitation suggested that acid on the leaf surface was neutralized by cations leached from leaf tissues and that Ca-S compounds were accumulated on the leaf surface (Kohno, 1994). This report summarizes visual observations of the neutralization process of acid on leaf surfaces as determined by a pH-imaging microscope. Small droplets of sulfuric acid were placed on the adaxial leaf surface and allowed to air dry under laboratory conditions. Droplets (0.1 µl) of sulfuric acid took about 7–8 minutes to dry. Leaf samples were cut at various times after the acid droplets dried. The adaxial leaf surface was placed on the pH-adjusted agar film layer on the pH-imaging sensor of the microscope. Hydrogen ions dispersed into the film layer and resulting pH distributions were visualized as pH distribution patterns. The size of the acidic area generated became smaller with time after the acid was added and allowed to dry. Results indicate that leaves could neutralize the surface acid probably by ion exchange with cations from their surface tissues and could recover from strong temporary acid stress imposed by acid rain or acid fog in a relatively short period of time. Our findings indicate that acidic precipitation at current acidity levels does not pose a direct threat to plants.     

Cell corpse engulfment mediated by C. elegans phosphatidylserine receptor through CED-5 and CED-12

During apoptosis, phosphatidylserine, which is normally restricted to the inner leaflet of the plasma membrane, is exposed on the surface of apoptotic cells and has been suggested to act as an "eat-me" signal to trigger phagocytosis. It is unclear how phagocytes recognize phosphatidylserine. Recently, a putative phosphatidylserine receptor (PSR) was identified and proposed to mediate recognition of phosphatidylserine and phagocytosis. We report that psr-1, the Caenorhabditis elegans homolog of PSR, is important for cell corpse engulfment. In vitro PSR-1 binds preferentially phosphatidylserine or cells with exposed phosphatidylserine. In C. elegans, PSR-1 acts in the same cell corpse engulfment pathway mediated by intracellular signaling molecules CED-2 (homologous to the human CrkII protein), CED-5 (DOCK180), CED-10 (Rac GTPase), and CED-12 (ELMO), possibly through direct interaction with CED-5 and CED-12. Our findings suggest that PSR-1 is likely an upstream receptor for the signaling pathway containing CED-2, CED-5, CED-10, and CED-12 proteins and plays an important role in recognizing phosphatidylserine during phagocytosis.     

Decreasing dietary lipids improves larval survival and growth of Japanese eel Anguilla japonica

Shark eggs-based diet is the only diet by which eel larvae can grow to glass eels in captivity. However, the high level of lipids in the diet is suggested to negatively affect eel larvae. This paper examines the effect of defatted shark eggs (DSE) and hen egg yolk (HY) on growth and survival of larvae of Japanese eel Anguilla japonica. Lyophilized shark egg and commercial HY were defatted with n-hexane, and four experimental diets were prepared using both defatted and untreated shark eggs and HY. Larvae were reared for 3 weeks by feeding the experimental diets. The highest survival rate was observed in the larvae fed DSE, and larvae fed HY showed the lowest survival rate. The best growth was found in larvae fed DSE, followed by shark eggs and defatted HY, and the worst growth was in HY-fed larvae. These results show that decreasing dietary lipids improves the nutritional value of both shark eggs and HY for eel larvae. Regulation of the dietary lipid level may positively affect the larval performance of eels by combination of ingredients with a low lipid content.     

Antimicrobial activity of licorice flavonoids against methicillin-resistant Staphylococcus aureus

Nineteen flavonoids isolated from licorice (Glycyrrhiza glabra, G. inflata and G. uralensis) were tested for their antimicrobial activities against methicillin sensitive Staphylococcus aureus, methicillin resistant S. aureus, Micrococcus luteus, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa.