Peptide profile of the sardine protein hydrolysate affects food utilization and intestinal microbiota of Nile tilapia

The present study evaluated effects of the degree of hydrolysis and peptide profile of sardine (Sardinella sp.) protein hydrolysates (SPH) from muscle tissue wastes on productive performance, body composition, hematological parameters, biochemical parameters of metabolism, antioxidant response, and intestinal microbiology tilapia (Oreochromis niloticus). Diets containing three SPH with different degrees of hydrolysis (low: 5.5%; intermediate: 27.9%, and high: 62.5%) were compared to a control diet with fish meal. The experimental design was completely randomized with four treatments and five repetitions. One hundred eighty tilapia juveniles (6.16?±?2.0 g) were distributed in 20 polyethylene tanks of 70 l of useful volume and were evaluated during 56 days. No direct relationship was observed between the degree of hydrolysis of SPH and fish productive performance. Feed consumption was reduced in all diets with SPH (means 53.03 g) compared to the control group (65.91 g), which impaired fish growth and metabolic reserves. Feed utilization was affected by the SPH peptide profile. SPH with a more diverse peptide profile (mean 1.40) had a feed efficiency similar to the control diet (1.22). Changes in biochemical and metabolic parameters in tissues, oxidative response, and microbial populations were observed but may be associated with the low consumption of diets containing SPH. Results suggest that it is necessary to properly characterize hydrolysates and understand their composition before applying fish feed.

     

Policosanol Content and Composition of Korean Rice (Oryza sativa L.) Cultivars

Policosanols (PCs) are a group of long‐chain alcohols that have been reported to have many beneficial physiological activities. In this study, the total content and composition of PCs in 15 rice (Oryza sativa L.) cultivars from Korea were characterized by gas chromatography–time‐of‐flight mass spectrometry. This method proved to be sufficiently precise and accurate with respect to the degree of endogenous biological variability found in the rice samples. Octacosanol (C28) and triacontanol (C30) were the major components of PCs in all cultivars. In addition, there were positive correlations among the determined PC contents. Given its high PC content, the Heughyangbyeo cultivar may appear to be a good candidate for future breeding programs.     

Patient-specific embryonic stem cells derived from human SCNT blastocysts

Patient-specific, immune-matched human embryonic stem cells (hESCs) are anticipated to be of great biomedical importance for studies of disease and development and to advance clinical deliberations regarding stem cell transplantation. Eleven hESC lines were established by somatic cell nuclear transfer (SCNT) of skin cells from patients with disease or injury into donated oocytes. These lines, nuclear transfer (NT)-hESCs, grown on human feeders from the same NT donor or from genetically unrelated individuals, were established at high rates, regardless of NT donor sex or age. NT-hESCs were pluripotent, chromosomally normal, and matched the NT patient's DNA. The major histocompatibility complex identity of each NT-hESC when compared to the patient's own showed immunological compatibility, which is important for eventual transplantation. With the generation of these NT-hESCs, evaluations of genetic and epigenetic stability can be made. Additional work remains to be done regarding the development of reliable directed differentiation and the elimination of remaining animal components. Before clinical use of these cells can occur, preclinical evidence is required to prove that transplantation of differentiated NT-hESCs can be safe, effective, and tolerated.     

Myosin V walks hand-over-hand: single fluorophore imaging with 1.5-nm localization

Myosin V is a dimeric molecular motor that moves processively on actin, with the center of mass moving approximately 37 nanometers for each adenosine triphosphate hydrolyzed. We have labeled myosin V with a single fluorophore at different positions in the light-chain domain and measured the step size with a standard deviation of <1.5 nanometers, with 0.5-second temporal resolution, and observation times of minutes. The step size alternates between 37 + 2x nm and 37 - 2x, where x is the distance along the direction of motion between the dye and the midpoint between the two heads. These results strongly support a hand-over-hand model of motility, not an inchworm model.     

玉米幼苗低温诱导蛋白的鉴定

研究以25℃为对照,以5℃低温胁迫处理,对水浸种和0.5%CaCl2浸种发芽培养的玉米幼苗进行蛋白电泳分析。蛋白质电泳扫描图谱分析结果表明,5℃低温诱导的玉米幼苗,24,48,96h均能合成新的诱导蛋白。     

现代园林花木生产企业管理节约型技术措施的应用初探

本文主要论述了在现代园林花木生产中部分节约型技术措施,如地毯式草坪快速生产技术、容器栽培技术、保水技术、施肥技术、复层种植技术、雨水利用技术等在节约型技术措施中的应用,从促进现代园林花木生产企业可持续发展方面进行了探讨。     

玉米芯栽培灵芝试验

本试验研究了玉米芯不同配方对灵芝菌丝生长及产量的影响。结果表明，菌丝在各配方培养料上均生长良好，各配方产量明显高于对照，尤其配方④产量达５．９０ｋｇ，比对照增产１３２．４％。     

Comparative study on the aflatoxin B1 degradation ability of rumen fluid from Holstein steers and Korean native goats

The aflatoxin B1 degrading abilities of two different ruminants were compared in this study. One set of experiments evaluated the aflatoxin B1 degradation ability of different rumen fluid donors (steers vs. goats) as well as the rumen fluid filtration method (cheese cloth filtered vs. 0.45 µm Millipore) in a 2 × 2 factorial arrangement. Additional studies examined aflatoxin B1 degradation by collecting rumen fluid at different times (0, 3, 6, 9 and 12 h) after feeding. Cannulated Holstein steers (740 ± 10 kg bw) and Korean native goats (26 ± 3 kg bw) were fed a 60% timothy and 40% commercial diet with free access to water. Rumen fluid from Korean native goats demonstrated higher (p < 0.01) aflatoxin B1 degradability than Holstein steers. However, filtration method had no significant influence on degradability. In addition, aflatoxin degradation did not depend upon rumen fluid collection time after feeding, as no significant differences were observed. Finally, a comparison of two types of diet high in roughage found aflatoxin degradability in goats was higher with timothy hay opposed to rice straw, although individual variation existed. Thus, our findings showed the aflatoxin degradability is comparatively higher in goats compared to steers.