Isolation and identification of symbiotic bacteria from the skin, mouth, and rectum of wild and captive tree shrews

Endosymbionts influence many aspects of their hosts’ health conditions, including physiology, development, immunity, metabolism, etc. Tree shrews(Tupaia belangeri chinensis) have attracted increasing attention in modeling human diseases and therapeutic responses due to their close relationship with primates. To clarify the situation of symbiotic bacteria from their body surface, oral cavity, and anus, 12 wild and 12 the third generation of captive tree shrews were examined. Based on morphological and cultural characteristics, physiological and biochemical tests, as well as the 16 S rDNA full sequence analysis, 12 bacteria strains were isolated and identified from the wild tree shrews: body surface: Bacillus subtilis(detection rate 42%), Pseudomonas aeruginosa(25%), Staphlococcus aureus(33%), S. Epidermidis(75%), Micrococcus luteus(25%), Kurthia gibsonii(17%); oral cavity: Neisseria mucosa(58%), Streptococcus pneumonia(17%); anus: Enterococcus faecalis(17%), Lactococus lactis(33%), Escherichia coli(92%), Salmonella typhosa(17%); whereas, four were indentified from the third generation captive tree shrews: body surface: S. epidermidis(75%); oral cavity: N.mucosa(67%); anus: L. lactis(33%), E. coli(100%). These results indicate that S. epidermidis, N. mucosa, L. lactis and E. coli were major bacteria in tree shrews, whereas, S. aureus, M. luteus, K. gibsonii, E. faecalis and S. typhosa were species-specific flora. This study facilitates the future use of tree shrews as a standard experimental animal and improves our understanding of the relationship between endosymbionts and their hosts.

Experimental study on thermo-hydraulic performances of nanofluids flowing through a corrugated tube filled with copper foam in heat exchange systems

Thermo-hydraulic characteristics of TiO_2-water nanofluids in thin-wall stainless steel test tubes(corrugated tube and circular tube) filled with copper foam(40 PPI) are experimentally investigated and compared with those in test tubes without copper foam. The effects of nanoparticle mass concentration on flow and heat transfer performances are investigated. In addition, the mutual restriction relationships between Reynolds number(Re), Nusselt number(Nu) and resistance coefficient(f) are discussed respectively. Also, the comprehensive coefficient of performance(CCP) between heat transfer and pressure drop is evaluated. The results show that core-enhancement region for heat transfer using experimental tubes filled with copper foam is notably different from that of tubes without copper foam. There is a corresponding Reynolds number(about Re = 2400) for the maximum CCP of each condition. And the heat transfer can be enhanced dramatically and sustained at 8000 ≤ Re ≤ 12000.

Effects of Long-term Located Fertilization on Evolution of Available Phosphorus and Phosphorus Pool in Shandong Fluvo-aquic Soil

This study was conducted to investigate the effects of long-term located fertilization on soil phosphorus,the changes of soil available phosphorus(OlsenP),the evolution of soil total phosphorus(TP)and the ratio change of Olsen-P to TP(PAC)by 33-year fertilization experiments in winter wheat-summer maize rotation system in Shandong fluvo-aquic soil.Eight treatments were designed as no fertilization(CK),nitrogen fertilizer(N),nitrogen and phosphate fertilizer(NP),nitrogen and potassium fertilizer(NK),phosphate and potassium fertilizer(PK),nitrogen-phosphate-potassium fertilizer(NPK),reduced NPK fertilizer(N(15)PK),and increased NPK fertilizer(N_(25)PK).Meanwhile,eight organic fertilizer-added treatments were designed based on the application of inorganic fertilizer the same as the above ones.The results showed that TP,Olsen-P and PAC of treatments added with organic fertilizer were higher than those without organic fertilizer,and those of the treatments applied with phosphate fertilizer were higher than those of no phosphate fertilizer.With the increase of years,soil P pool decreased due to crop absorption,nutrient loss and morphological transformation and other causes under the treatments of without and only phosphate fertilizer,while remained stable under the treatments added with organic fertilizer.The PAC values were generally lower in fluvo-aquic soil,and it could be improved by the application of organic fertilizer.On the whole,the application of chemical phosphate fertilizer combined with organic fertilizer could improve the phosphorus content in soil and ensure the supply of phosphorus nutrition.This study would provide scientific basis for fertilization management and soil fertility in fluvo-aquic soil.

CHEMICAL MODIFICATION INCREASE THE ACTIVITY AND ENANTIOSELECTIVITY OF CANDIDA LIPOLYTICA LIPASE

Abstract: In this work, the edfffects of chemical modification on the activity and enantioselectivity of Candida lypolytica lipase in resolution of Ibuprofen were reported.