Enhanced anthocyanin production by repeated-batch culture of strawberry cells with medium shift

Repeated-batch cultures of strawberry cells (Fragaria ananassa cv. Shikinari) subjected to four medium-shift procedures (constant LS medium, constant B5 medium, alternation between LS and B5 starting from LS and alternation between LS and B5 starting from B5) were investigated for the enhanced anthocyanin productivity. To determine the optimum period for repeated batch cultures, two medium-shift periods of 9 and 14 days were studied, which represent the end of the exponential growth phase and the stationary phase. By comparison with the corresponding batch cultures, higher anthocyanin productivity was achieved for all the repeated-batch cultures at a 9-day medium-shift period. The average anthocyanin productivity was enhanced 1.7-and 1.76-fold by repeated-batch cultures in constant LS and constant B5 medium at a 9-day shift period for 45 days, respectively. No further improvement was observed when the medium was alternated between LS (the growth medium) and B5 (the production medium). Anthocyanin production was unstable at a 14-day shift period regardless of the medium-shift procedures. The results show that it is feasible to improve anthocyanin production by a repeated-batch culture of strawberry cells.

Changes in the properties of Bacillus thuringiensis after prolonged culture in a rich medium

AIM: To investigate the effect of repeated culture in a rich medium on certain genetic, metabolic, pathogenic and structural characteristics of fresh isolates of Bacillus thuringiensis. METHODS AND RESULTS: Four strains of B. thuringiensis, which had been isolated in vegetative form from leaf surfaces, were grown for 500 generations in batch culture in a rich medium. One of the strains, S4g, differed from the parent in the following respects: greater cell width; changed plasmid profile; complete loss of ability to produce delta-endotoxins; loss of ability to produce beta-exotoxin and disruption of vip3 gene; radically different fatty acid composition; and altered metabolic activity. Two of the other evolved strains (S1g and S6g) showed differences in fatty acid profiles compared with the parents. Genetic finger-printing showed that there were also mutations in the cry genes of two of the evolved strains (S1g and S2g). The delta-endotoxins of strain S6g were significantly less toxic to the larvae of Pieris brassica compared with those of the parent and it also differed in the plasmid content. CONCLUSION: Radical and unpredictable changes can occur in fresh isolates of B. thuringiensis when subjected to growth in the laboratory. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first analysis of a Gram positive and biotechnologically significant bacterium after repeated laboratory culture. It is of great relevance to the biotechnological exploitation of B. thuringiensis that prolonged growth of environmental isolates on laboratory culture media can have profound effects on their structure, genome and virulence determinants.

Company size, organisational culture and human resource management in small to medium sized professional services firms: a case study

Cultura organizacional e gestão de recursos humanos (GRH) são componentes fundamentais para a estratégia corporativa raramente estudada no contexto das pequenas e médias empresas (PME) no setor de serviços profissionais, um ambiente no qual o capital humano das empresas companhias é particularmente importante. Um estudo de caso de uma empresa de gestão de investimentos inglesa foi realizado. A PME quase triplicou o seu quadro de funcionários, de menos de 50 a mais de 140, nos últimos seis anos. Cultura e GRH foram pesquisadas tanto historicamente quanto no momento atual por meio de uma combinação de entrevistas individuais, observação direta durante as visitas ao local e análise documental. Foi verificado que a G RH (junto com um número de outras estruturas e processos internos) tornou-se mais formal, apesar do fato de que a empresa começou com políticas de RH relativamente desenvolvidas, em comparação com outras pequenas empresas. Uma possível explicação para esta estruturação das práticas de RH é que empresas do setor de serviços profissionais tendem a dar uma importância especial à qualidade da sua força de trabalho. Esta relativa estabilidade cultural pode ser explicada pelo fato da cultura ser forte e é mantida tanto inconscientemente quanto conscientemente, por meio de mecanismos como o planejamento de pessoal, recrutamento e remuneração. As conclusões, por conseguinte, demonstram que as atitudes e percepções nem sempre mudam tão rápido quanto sistemas organizacionais, e que a relação entre cultura e gestão de recursos humanos pode ser complexa; a formalização da GRH pode reforçar a mudança cultural em certos aspectos, ao mesmo tempo abrandá-lo em outros.

Antibiosis associated to Lactobacillus acidophilus growth .2. Optimization of some culture parameters in whey and soy milk medium

Whey supplemented with soy milk has been used as a low-cost alternative in the growth of Lactobacillus acidophilus for the production of antimicrobial compounds. Response Surface Metodology has been employed in order to study the effects of initial pH, incubation temperature and soy milk rate for supplementation in the production of antimicrobial substance. It has been observed that both tested microrganisms used (S. aureus and E. coli) were inhibited by antimicrobial substance produced by L. acidophilus. The results obtained with E. coli inhibition did not follow the employed statistical model. on the other hand, when the tested microorganism S. aureus was used, the best inhibition results have been obtained when L. acidophilus was incubated at 36.80 degrees C in whey with 5.6 initial pH and 31,90% (v/v) rate supplemented with soy milk. The analysed antimicrobial substances were nor acids neither hidrogen peroxid.

Synergistic action of both Aspergillus niger and Burkholderia cepacea in co-culture increases phosphate solubilization in growth medium

Co-inoculation of the fungus Aspergillus niger and the bacterium Burkholderia cepacia was undertaken to understand the interaction between different species of phosphate-solubilizing microorganisms (PSM). PSM were inoculated in a single or mixed (A. nigerB.similar to cepacia) culture. During 9 similar to days of incubation, microbial biomass was enhanced, accompanied with increases in the levels of soluble phosphate and titratable acidity, as well as increased acid phosphatase activity. Production of acids and levels of phosphate solubilization were greater in the co-culture of A.similar to nigerB.similar to cepacia than in the single culture. The quantity of phosphate solubilized by the co-culture ranged from 40.51 +/- 0.60 to 1103.64 +/- 1.21 similar to mu g similar to PO4 3-similar to mL-1 and was 922% higher than single cultures. pH of the medium dropped from 7.0 to 3.0 in the A.similar to niger culture, 3.1 in the co-culture, and 4.2 in the B.similar to cepacia culture. on the third day of postinoculation, acid production by the co-culture (mean 5.40 +/- 0.31 similar to mg NaOH mL-1) was 1990% greater than single cultures. Glucose concentration decreased almost completely (9799% of the starting concentration) by the ninth day of the incubation. These results show remarkable synergism by the co-culture in comparison with single cultures in the solubility of CaHPO4 under in vitro conditions. This synergy between microorganisms can be used in poor available phosphate soils to enhance phosphate solubilization.

Activation of intervertebral disc cells by co-culture with notochordal cells, conditioned medium and hypoxia

Notochordal cells (NC) remain in the focus of research for regenerative therapy for the degenerated intervertebral disc (IVD) due to their progenitor status. Recent findings suggested their regenerative action on more mature disc cells, presumably by the secretion of specific factors, which has been described as notochordal cell conditioned medium (NCCM). The aim of this study was to determine NC culture conditions (2D/3D, fetal calf serum, oxygen level) that lead to significant IVD cell activation in an indirect co-culture system under normoxia and hypoxia (2% oxygen).

Self-renewal of primitive human hematopoietic cells (long-term-culture-initiating cells) in vitro and their expansion in defined medium.

A major goal of experimental and clinical hematology is the identification of mechanisms and conditions that support the expansion of transplantable hematopoietic stem cells. In normal marrow, such cells appear to be identical to (or represent a subset of) a population referred to as long-term-culture-initiating cells (LTC-ICs) so-named because of their ability to produce colony-forming cell (CFC) progeny for > or = 5 weeks when cocultured with stromal fibroblasts. Some expansion of LTC-ICs in vitro has recently been described, but identification of the factors required and whether LTC-IC self-renewal divisions are involved have remained unresolved issues. To address these issues, we examined the maintenance and/or generation of LTC-ICs from single CD34+ CD38- cells cultured for variable periods under different culture conditions. Analysis of the progeny obtained from cultures containing a feeder layer of murine fibroblasts engineered to produce steel factor, interleukin (IL)-3, and granulocyte colony-stimulating factor showed that approximately 20% of the input LTC-ICs (representing approximately 2% of the original CD34+ CD38- cells) executed self-renewal divisions within a 6-week period. Incubation of the same CD34+ CD38- starting populations as single cells in a defined (serum free) liquid medium supplemented with Flt-3 ligand, steel factor, IL-3, IL-6, granulocyte colony-stimulating factor, and nerve growth factor resulted in the proliferation of initial cells to produce clones of from 4 to 1000 cells within 10 days, approximately 40% of which included > or = 1 LTC-IC. In contrast, in similar cultures containing methylcellulose, input LTC-ICs appeared to persist but not divide. Overall the LTC-IC expansion in the liquid cultures was 30-fold in the first 10 days and 50-fold by the end of another 1-3 weeks. Documentation of human LTC-IC self-renewal in vitro and identification of defined conditions that permit their extensive and rapid amplification should facilitate analysis of the molecular mechanisms underlying these processes and their exploitation for a variety of therapeutic applications.

The ecology of paper mill by-product and its evaluation as a casing medium in the culture of Agaricus bisporus (Lange) Pilat

Effluent from pulp and paper production at the Kemsley mill of Bowaters U.K. Paper Company Limited passes through two treatment stages before its discharge into the Swale estuary. Suspended material removed during treatment is deposited on wasteground as a thin sludge. The solids it contains are mainly wood components lost during pulp production, whilst it also has a high salt content, derived from chemicals used in pulping processes. After deposition the sludge undergoes an ageing process during which it dries out and its salt content is reduced. This ageing can be reproduced and accelerated by improved drainage under controlled conditions. The paper mill sludge was investigated as a casing medium in the culture of Agaricus bisporus (Lange) Pilat, the cultivated mushroom. It was unsuitable up to one year from deposition due largely to the inhibitory effect of its salt content on fruiting. Material eighteen months or more in age gave yields comparable to standard peat casing. Before use as a casing the material must be shredded to a satisfactory structure, neutralised with chalk, and pasteurised to eliminate organisms harmful to the crop. The prepared medium has a high water holding capacity and a structure resilient to management procedures, important requirements of a good casing. A passive movement of salts from the compost to the casing was shown to occur during culture, capable of enhancing the natural decline in cropping if sufficiently great. The ions chloride, potassium, sodium and sulphate were shown to be responsible, their damaging effects being due to high conductivity created in the casing. Studies of elements available during culture suggested phosphate availability in the compost could limit crop potential, whilst iron released by mycelium of A.bisporus in the casing may be utilised by associated micro-organisms.

On medium specificity and discipline crossovers in modern art : An interview with Jacques Ranciére on Medium-Specificity and Discipline Crossovers in Modern Art

Jacques Ranciere's work on aesthetics has received a great deal of attention recently. Given his work has enormous range – taking in art and literature, political theory, historiography, pedagogy and worker's history – Andrew McNamara and Toni Ross (UNSW) seek to explore his wider project in this interview, while showing how it leads to his alternative insights into aesthetics. Rancière sets aside the core suppositions linking the medium to aesthetic judgment, which has informed many definitions of modernism. Rancière is emphatic in freeing aesthetic judgment from issues of medium-specificity. He argues that the idea of autonomy associated with medium-specificity – or 'truth to the medium' – was 'a very late one' in modernism, and that post-medium trends were already evident in early modernism. While not stressing a simple continuity between early modernism and contemporary art, Ranciere nonetheless emphasizes the ethical and political ramifications of maintaining an a-disciplinary stance.

Comparison of human alveolar osteoblasts cultured on polymer-ceramic composite scaffolds and tissue culture plates

The effects of medical grade polycaprolactone–tricalcium phosphate (mPCL–TCP) (80:20) scaffolds on primary human alveolar osteoblasts (AOs) were compared with standard tissue-culture plates. Of the seeded AOs, 70% adhered to and proliferated on the scaffold surface and within open and interconnected pores; they formed multi-layered sheets and collagen fibers with uniform distribution within 28 days. Elevation of alkaline phosphatase activity occurred in scaffold–cell constructs independent of osteogenic induction. AO proliferation rate increased and significant decrease in calcium concentration of the medium for both scaffolds and plates under induction conditions were seen. mPCL–TCP scaffolds significantly influenced the AO expression pattern of osterix and osteocalcin (OCN). Osteogenic induction down-regulated OCN at both RNA and protein level on scaffolds (3D) by day 7, and up-regulated OCN in cell-culture plates (2D) by day 14, but OCN levels on scaffolds were higher than on cell-culture plates. Immunocytochemical signals for type I collagen, osteopontin and osteocalcin were detected at the outer parts of scaffold–cell constructs. More mineral nodules were found in induced than in non-induced constructs. Only induced 2D cultures showed nodule formation. mPCL–TCP scaffolds appear to stimulate osteogenesis in vitro by activating a cellular response in AO's to form mineralized tissue. There is a fundamental difference between culturing AOs on 2D and 3D environments that should be considered when studying osteogenesis in vitro.

Small and medium enterprises’ solution to improve on-site waste management in office building retrofit projects

Office building retrofit projects are increasingly more intensified as existing buildings are aging. At the same time, building owners and occupants are looking for environmentally sustainable products. These retrofit projects usually take place in center business district (CBDs) with on-site waste becoming one of the critical issues. Small and Medium Enterprises (SMEs) carry out most of the work in retrofit projects as subcontractors. Despite their large involvement, they often do not have adequate resources to deal with the specific technical challenges and project risks related to waste. Few research has been done on their performance of waste management operations. This paper identifies characteristics of on-site waste in office building retrofit projects. It examines the specific requirements for contractors to manage waste in the projects before exploring the existing performance of SMEs. By comparing requirements for SMEs and their potential areas for improvement, a framework is established for performance promotion of SMEs in on-site waste management of office building retrofit projects. The paper will raise the consciousness and commitment of SMEs as sub-contractors to waste management. It also explores ways of supporting SMEs for experience accumulation, performance promotion and project culture establishment towards effective and efficient on-site waste management in the growing sector of office building retrofit and upgrade.