Recovery of Salmonella from refrigerated preenrichment and refrigerated enrichment media

The productivity of the standard cultural procedure for the isolation of Salmonella using preenrichment in buffered peptone water (BPW) followed by inoculation into Rappaport-Vassiliadis (RV), tetrathionate (TBG) (Difco) and selenite-cystine (SC) (Difco) enrichment broths, was compared with that using preenrichment and enrichment cultures which had been held under refrigeration (72 h at 5–10°C). Seventy-seven of 251 samples of food products were found to contain Salmonella. Refrigerated preenrichment cultures inoculated into RV medium (43°C), TBG broth (43°C) and SC broth (37°C) yielded salmonellae from 93.5, 85.7 and 54.5% contaminated samples, respectively. Refrigerated cultures in RV, TBG and SC broths, inoculated onto three selective plating media, identified 100, 87.0 and 41.6% of the contaminated samples, respectively.The selective plating medium brilliant green deoxycholate agar was at least as productive as brilliant green sulpha agar and bismuth sulphite agar, when streaked from RV and TBG broths, but was less effective when streaked from SC broth.     

Consumer Attitudes Toward Use of Probiotic Cultures

ABSTRACT: Some probiotic cultures appear to modulate the immune system, improve lactose intolerance, resolve some bacterial and viral diarrheal diseases, reduce symptoms associated with inflammatory bowel disease, lower blood cholesterol, and protect against some cancers. Focus groups were used to determine consumer familiarity with probiotic bacteria and response to benefits, information source, potential health claims, and dietary sources. Some consumers were skeptical that probiotic cultures could be effective. Information is more credible if it is consistent with existing beliefs and endorsed by recognized health experts. Consumers aware of "friendly bacteria" in yogurt were more likely to accept the potential benefits of probiotic cultures than consumers unaware of beneficial bacteria. Some consumers were so sensitive to the risks of pathogenic bacteria that the concept of beneficial bacteria was not credible.     

Genome Subtyping of Autochthonous Bacillus Species Isolated from Iru,a Fermented Parkia biglobosa Seed

Phylogenetic relationship and strains sub-typing of Bacillus species isolated from iru, a traditional fermented condiment in Africa were studied using polyphasic genomic approaches and the profiles compared with bacilli isolated from similar Asian condiments. The 16S rRNA gene sequencing identified the strains as Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus cereus, Bacillus licheniformis, Bacillus pumilus, and Brevibacillus formosus. The phylogenetic analysis conducted showed five distinct clusters with genetic relatedness among B. subtilis and B. amyloliquefaciens strains from Africa and Asia. Amplified ribosomal DNA restriction analysis (ARDRA) successfully differentiated species of B. subtilis phylogeny from B. cereus. Combined analyses of ARDRA, internal transcribed spacer-polymerase chain reaction (ITS-PCR), ITS-PCR-restriction fragment length polymorphism (ITS-PCR-RFLP) and randomly amplified polymorphic DNA (RAPD-PCR) further confirmed B. subtilis and B. amyloliquefaciens as the dominant Bacillus species associated with fermentation of iru, and revealed high strains genetic diversity, while multilocus sequence analysis (MLSA) data distinguished B. cereus from B. thuringiensis. This information is essential for selection of starter cultures with desirable functional attributes to guarantee product consistency and safety quality of traditional fermented foods.     

Enhancement of γ-aminobutyric acid (GABA) in Nham (Thai fermented pork sausage) using starter cultures of Lactobacillus namurensis NH2 and Pediococcus pentosaceus HN8

The aim was to produce Nham that was enriched with γ-aminobutyric acid (GABA); therefore two GABA producing lactic acid bacteria (Pediococcus pentosaceus HN8 and Lactobacillus namurensis NH2) were used as starter cultures. By using the central composite design (CCD) we showed that addition of 0.5% monosodium glutamate (MSG) together with an inoculum size of roughly 6 log CFU/g of each of the two strains produced a maximal amounts of GABA (4051 mg/kg) in the ‘GABA Nham’ product. This was higher than any current popular commercial Nham product by roughly 8 times. ‘GABA Nham’ with the additions of both starters and MSG (T_SM) supported maximum populations of lactic acid bacteria (LAB) with a minimum of yeasts and no staphylococci or molds when compared to the controls that had no addition of any starters or MSG (T_NN), or only the addition of MSG (T_NM), or with only the starter (T_SN). Based on proximate analysis among the Nham sets, ‘GABA Nham’ was low in fat, carbohydrate and energy although its texture and color were slightly different from the control (T_NN). However, sensory evaluations of ‘GABA Nham’ were more acceptable than the controls and commercial Nham products for all tested parameters. Hence, a unique novel ‘GABA Nham’ fermented pork sausage was successfully developed.     

传统面食发酵剂中菌群多样性的研究

我国传统面食发酵剂的使用具有悠久的历史,其制作的馒头、包子等发酵食品因风味独特而深受大家喜爱,但对传统面食发酵剂中微生物菌群的研究却非常薄弱。本文以河南地区的传统面食发酵剂为对象,采用分离培养及分子鉴定技术对其微生物生态多样性进行了研究。通过对微生物基本形态特征观察结合生理生化试验及分子鉴定技术,将分离到的30株酵母菌鉴定为4类,其中11株为酿酒酵母(Saccharomyces cerevisiae),6株为异常毕赤酵母(Pichia anomala),8株为东方伊萨酵母(Issatchenkia orientalis),5株为扣囊复膜酵母(Saccharomycopsis fibuligera),其中酿酒酵母(Saccharomyces cerevisiae)为优势酵母菌种;分离的28株乳酸菌中13株为植物乳杆菌(Lactobacillus plantarum),8株为粪肠球菌(Enterococcus faecalis),7株为干酪乳杆菌(Lactobacillus casei),其中植物乳杆菌(Lactobacillusplantarum)为优势乳酸菌。此外,样品中还分离到了一株霉菌,经鉴定为米根霉(Rhizopus oryzae)。     

Religion's influence on culture and psychology.

Comments on E. Sampson's (see record 2001-16333-002) linking individualism and collectivism to religious origins. The author provides examples of cultures which are both Christian and collectivist, in contrast to what is predicted by Sampson's theory. The author draws upon comments made by L. S. Vygotsky on the culture of precommunist Russia to highlight the difficulty with abstracting the influence of religion on individualism and collectivism from the traditional East-West framework. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

针对电大学生实际,加强思想素质教育

本文从分析电大校情及学生实际入手,确定对学生进行思想教育的基本思路,即：以提高学生的思想道德素质为目的,以严肃校规校纪为前提,以思想品德课为主渠道,以校园文化为载体,以学校教育为主阵地,以家庭教育为有力配合,通过突出“五个针对”从各个方面阐述增强教育的实效性。     

禅宗心灵的表现──日本著名景观设计师■野俊明及其作品

■野俊明被誉为最具日本传统园林风格的现代景观设计师。由于他出生在一个禅僧世家,所以从他的作品中可以充分体验到日本传统文化在景观设计中的表现。     

DNA Hydrogels as Functional Materials and Their Biomedical Applications

With the remarkable development of DNA nanotechnology, interest in DNA molecules has expanded beyond its biological role to building blocks in materials science. As a unique branch of DNA-based materials, DNA hydrogels have exhibited many fascinating characteristics, including broad biocompatibility, precise programmability, convenient modification, and tunable mechanical properties, which make DNA hydrogels ideal biomaterials. Moreover, by combining with functional nucleic acids, such as aptamers, i-motif nanostructures, CpG oligodeoxynucleotides, and DNAzymes, DNA hydrogels can be further tailored to provide additional target recognition, therapeutic potential, and catalytic activities, allowing them to play important roles in biosensing and medical applications. This review, aims to provide readers with an up-to-date overview of the important developments of biomedical DNA hydrogels. First, it introduces different synthetic strategies of hydrogels that utilize DNA as building materials and functional units within the hydrogel networks and discuss their advantages in biomedical applications. Subsequently, new approaches and applications of biomedical DNA hydrogels in the recent years are highlighted, such as therapeutic systems, cell culture platforms, tissue engineering materials, and biosensors. Finally, future perspectives and remaining challenges of DNA hydrogels in biomedicine are presented.