Effect of various liquid culture media on morphology,growth, propagule production,and pathogenic activity to Bemisia argentifolii of the entomopathogenic Hyphomycete,Paecilomyces fumosoroseus

The entomopathogenic Hyphomycete Paecilomyces fumosoroseus was grown in five different liquid media, which have been developed for mass production of Beauveria spp. or P. fumosoroseus. Production was followed for 96 h by measuring both biomass and concentration of propagules. Maximal biomass was obtained with two media, Jackson and Catroux media (40–60 mg ml-1 suspension produced after 42 h incubation), where the exponential phase of growth began earlier than in the other media. While high concentrations of propagules (1.4–5.5 × 108 propagules ml-1) were produced in three media (Jackson, Paris, and Catroux media) after 48–72 h incubation, production of propagules was lower in the two other media, containing maltose as carbon source (Goral and Kondryatiev media) with 0.4–3.7 × 107 propagules ml-1 after 96 h incubation. P. fumosoroseus produced oblong blastospores in the three most productive media and conidiospore-like (ovoid to subspherical) propagules in the two other media. Infection potential of produced propagules was tested on the silverleaf whitefly ( Bemisia argentifolii). Whiteflies were sprayed as 2nd instars with P. fumosoroseus propagules produced in the five liquid media (1.9 × 103 and 1.9 × 104 propagules cm-2). All the media produced propagules that were infectious for larvae. With the lower dosage, mortality rates were significantly lower with propagules produced in one of the two least productive media (57%) (in the Kondryatiev medium) compared to those obtained with the three most productive media (>90%). However, when whiteflies were treated with the higher dosage, mortality rates (91–99%) between media were not significantly different. This revised version was published online in June 2006 with corrections to the Cover Date.     

Culture medium pH is influenced by basal medium,carbohydrate source,gelling agent,activated charcoal,and medium storage method

Summary When four carbohydrates were tested against six commonly cited inorganic basal media, post-autoclave pH was highest for carbohydrate-free and sucrose containing media, and progressively lower for maltoseglucose and fructose-containing media, respectively. Post-autoclave pH for these media without carbohydrates was related to medium buffering capacity. Addition of gelling agents (10 of 11 tested) increased the postautoclave pH of MS medium containing sucrose. Neutralized and acid-washed activated charcoal also increased the post-autoclave pH of liquid and agarsolidified MS medium, and the pH changed further during 8 weeks of storage. Changes in medium pH caused by gelling agents, but not charcoal, could be alleviated by adjusting the pH after their addition but prior to autoclaving.     

Effects of freeze-drying on cytology, ultrastructure, DNA fragmentation, and fertilizing ability of bovine sperm

Freeze-drying sperm is an alternative to cryopreservation. Although sperm from various species has been freeze-dried, there are few reports for bovine sperm. The primary objective of this study was to evaluate the protective effect of various freeze-drying media on the structural and functional components of bovine sperm. The media tested were composed of TCM 199 with Hanks salts supplemented with 10% fetal calf serum (FCS) and TCM 199 with Hanks salts supplemented with 10% FCS and 0.2 M trehalose and EGTA solution. The efficiency of each medium on the preservation of freeze-dried sperm structures was evaluated with conventional and electron microscopy, DNA integrity was analyzed by a TUNEL assay, and fertilizing ability of lyophilized sperm was determined with ICSI. Although the plasma membrane was damaged in all media tested, mitochondria were similarly preserved in all freeze-drying treatments. The acrosome was best preserved in the media that contained trehalose (other treatments also conserved this structure). In contrast, media containing EGTA or trehalose most effectively preserved the nuclei in freeze-dried sperm, with only 2 and 5%, respectively, of cells with fragmented DNA. Furthermore, sperm conserved with these media also had higher (P<0.05) rates of sperm head decondensation (32.5 and 27.5%), pronucleus formation (37.5 and 45.0%) and blastocyst formation (19.4 and 18.3%) than medium supplemented with FCS (15.0, 20.0 and 10.2%, respectively). In conclusion, media with EGTA and trehalose adequately protected bovine sperm during freeze-drying by preserving the viability of their nuclei.     

An Alternative Gelling Agent for Culture and Studies of Nematodes,Bacteria, Fungi,and Plant Tissues

Pluronic F127 polyol, a block copolymer of propylene oxide and ethylene oxide, was studied as an alternative to agar in culture media for nematodes, bacteria, fungi, actinomycetes, and plant tissues or seedlings, At a polyol concentration of 20% w/v, the culture media, semi-solid at room temperature (22 C) but liquid at lower temperatures, had minimal effects on the test organisms. Most of the fungi and bacteria grew as well in 20% polyol as in 1.5% agar media; however, various species of nematodes and plant seedlings or tissues exhibited differential sensitivities to different concentrations of the polyol. In cases where the organisms were unaffected, the polyol media had certain advantages over agar, including greater transparency and less contamination under nonaseptic conditions. Polyol media have potentially greater ease for recovery of embedded organisms or tissues inside the media by merely shifting to lower temperatures.     

Children's Television,Radio, Internet,and Computer Usage in a City and a Village of China

A first step in understanding media consumption is to understand the time people spend using media, and how usage varies across demographic groups and in response to other factors. While there is ample research from the West, research from China is less evident. Here I provide a case study of children's media usage in a rural and an urban area in China. The findings showed that a greater proportion of children in the urban sample used media such as television, Internet, and computer games, and that rural–urban residency had the most significant influence on television viewing. Further, more urban children reported their parents had concerns about media usage, whereas a greater proportion of children in the rural area had televisions in their bedrooms and ate meals while watching television. This difference was explained by differences in socio-economic levels, traditional values, and educational background. The findings show that the rural–urban difference, and other factors such as parental concern, should be considered when conducting and interpreting media consumption. There also are implications for health because a large proportion of children in the present study had televisions in their bedrooms and ate while watching television, and such behaviors in the West have been associated with unhealthy lifestyles.     

培养液及其浓度和pH值对草履虫种群增长的影响

采用稻草、小麦、奶粉、酵母、玉米粒、荷叶等6种培养液培养草履虫,结果表明,稻草、玉米粒和奶粉培养液为草履虫的理想培养液。另外,对上述3种理想培养液的不同浓度和稻草培养液的不同pH值影响草履虫的生长繁殖进行了实验研究,统计分析表明影响较为明显。稻草培养液的最适浓度为1%~2%;奶粉培养液的最适浓度为0.1%~0.2%;玉米粒培养液的最适浓度为1%~2%;稻草培养液最适pH值为7.0。     

Heavy metals (Cd, Pb, Zn, Ni, Cu and Cr(III)) removal from water in Malaysia: post treatment by high quality limestone

This paper presents the results of research on heavy metals removal from water by filtration using low cost coarse media which could be used as an alternative approach to remove heavy metals from water or selected wastewater. A series of batch studies were conducted using different particle media (particle size 2.36-4.75 mm) shaken with different heavy metal solutions at various pH values to see the removal behaviour for each metal. Each solution of cadmium (Cd), lead (Pb), zinc (Zn), nickel (Ni), copper (Cu) and chromium (Cr(III)) with a concentration of 2 mg/L was shaken with the media. At a final pH of 8.5, limestone has significantly removed more than 90% of most metals followed by 80% and 65% removals using crushed bricks and gravel, respectively. The removal by aeration and settlement methods without solid media was less than 30%. Results indicated that the removal of heavy metals was influenced by the media and not directly by the pH. Investigations on the removal behaviour of these metals indicated that rough solid media with the presence of carbonate were beneficial for the removal process. Adsorption and precipitation as metals oxide and probably as metals carbonate were among the two mechanisms that contributed to the removal of metals from solution.     

Effect of conditioned media on three genotypes of Drosophila melanogaster: Physical,chemical, and biological aspects

The uric acid contents in larvae, pupae, and culture media were studied during larval and pupal development in three genotypes of Drosophila melanogaster reared in both crowded and noncrowded conditions. The uric acid content and the response of genotypes in media supplemented with 10 and 15 mg/ml of uric acid were correlated with the outcome obtained in conditioned media. In addition, the behavior of genotypes in conditioned media is explained in terms of the physicochemical properties of the conditioned media, which include uric acid content, the amount of food ingested, the degree of free water, the physical disturbance within the cultures, and the particular response of each genotype to uric acid.     

Evaluation of Media for Selective Isolation of Yeasts from Oral, Rectal, and Burn Wound Specimens

Six media were evaluated to determine their ability to isolate yeasts and inhibit bacteria. The media included the following: Snyder, Snyder tellurite, Sabouraud tellurite, Littman-gentamicin, molybdate, and Mycosel (BBL). Doses of mixed intestinal gram-negative bacilli and enterococci were most effectively inhibited by Snyder tellurite agar. Klebsiella pneumoniae was the most common bacterial contaminant of the other media. All six media were comparable in isolating yeasts while preventing the growth of the oral bacterial flora. The selection of a basal fungal growth medium for tellurite incorporation to inhibit bacteria but permit growth of yeasts was affected by pH. The bacteriostatic effect of tellurite was decreased with increasing pH of media while fungistatic action was increased. The arbitrary selection of Snyder and Littman agars to isolate yeast from burn wound cultures demonstrated the need to include a selective medium for these specimens. Blood, phenylethyl alcohol blood agar, and Columbia CN blood agar were all inadequate for isolating yeasts from burns. Growth of a variety of filamentous saprophytic and pathogenic dimorphic fungi grew adequately on four of five selective media tested.     

Polygalacturonase,biomass, and ascospore production by byssochlamys fulva. I. Effects of acids found in fruits

Polygalacturonase, biomass, and ascospore production by four strains of Byssochlamys fulva cultured in laboratory media supplemented with citric, malic, or tartaric acids was determined over a 20-day incubation period at 30°C. Polygalacturonase activity was higher in tartaric acid media than in malic or citric acid media, with 1 % acid supporting the greatest activity in media initially at pH 4 or 5; at 0.1 % acid, highest activity was noted in media initially at pH 3. Most activity was produced between 4 and 8 days of incubation. Malic acid supported greater biomass production than did citric or tartaric acids. Media containing tartaric acid was the best for the production of ascospores whereas citric acid was the poorest. Higher numbers of ascospores generally were produced in media initially at pH 3 as compared to pH 4 or 5 after 10 days of incubation.     

Interactive effects of solutes, potassium sorbate and incubation temperature on growth, heat resistance and tolerance to freezing of Zygosaccharomyces rouxii.

The interactive effects of solutes, potassium sorbate and incubation temperature on growth, heat resistance and tolerance to freezing of Zygosaccharomyces rouxii were investigated. Growth rates in media supplemented with glucose, sucrose or NaCl to aw 0.93 were more rapid than in unsupplemented media (aw 0.99). Although growth in unsupplemented medium was lower at 35 degrees C, incubation at 21 degrees C or 35 degrees C had little effect on growth in media supplemented with glucose and sucrose. The addition of 300 micrograms potassium sorbate/ml to media resulted in reduced growth rates, particularly at 35 degrees C. Heat resistance of Z. rouxii was substantially greater in cultures previously incubated at 35 degrees C than in cultures incubated at 21 degrees C in media both with and without 300 micrograms potassium sorbate/ml. Zygosaccharomyces rouxii was tolerant to freezing at -18 degrees C for up to 120 d in all test media supplemented with glucose, sucrose or NaCl. The addition of 300 micrograms potassium sorbate/ml to sucrose-supplemented media resulted in increased resistance to freezing in cultures previously incubated at 21 degrees C. Sensitivity to freezing increased when cultures were incubated at 21 degrees C in media not supplemented with solutes. Glucose and sucrose provided the best protection against inactivation by heating and freezing, regardless of the presence of potassium sorbate in growth media.     

Colonization and turnover of Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis in otitis-prone children

Recurrent otitis media are frequently intractable during childhood. It is unclear whether recurrent otitis media is caused by etiological bacteria colonization or by new infections. Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis were isolated from the nasopharynx of 7 otitisprone and 2 non-prone children with recurrent otitis media. Plural bacterial species and strains were found in all children while affected by otitis media. The same strain was repeatedly isolated from all otitisprone children even after administration of antibiotics but was not from the non-prone children. Antibiotic susceptibility did not differ significantly among the same repeatedly isolated strains. This pilot study suggests that the etiological bacteria tend to colonize and is hard to eliminate in otitis-prone children.     

Effect of liquid culture media on morphology,growth, propagule production,and pathogenic activity of the Hyphomycete,Metarhizium flavoviride

Two isolates of Metarhizium spp. were studied for propagule production, because of their pathogenic activity towards locusts and grasshoppers (Mf189 = M. flavoviride (or M. anisopliae var. acridum) strain IMI 330189, and Mf324 = M. flavoviride strain ARSEF324). Both isolates were grown in seven different liquid media, which have been developed for mass production of various Hyphomycetes, considered as candidates for microbial control of noxious insects. Shake-flask experiments were carried out at 28 °C in the dark. Production was quantified for 72 h and the effects of the tested media were evaluated on propagule concentration, morphology and pathogenicity. Based on preliminary experiments, all tested media were supplemented with 0.4% Tween 80 to avoid the formation of pellets and to produce unicellular propagules. Submerged propagule yields were higher withMf189 than with Mf324 in all seven media. While high concentrations of propagules (1.4 to 2.4 × 10⁸ propagules ml^-1 for MF189 and1.4 to 8.3 × 10⁷ propagules ml^-1 for Mf324) were produced in four media (Adamek, Catroux, Jackson, and Jenkins–Prior media), production of propagules was lower in the three other media (Goral, Kondryatiev, and Paris media). Both isolates produced oblong blastospore-like propagules, except in Kondryatiev medium in which they provided ovoid propagules. In this case, Mf189 submerged propagules looked like aerial conidia, but scanning observations did not demonstrate a typical conidiogenesis via phialides. In Kondryatiev medium, Mf324 submerged propagules were significantly smaller than aerial conidia. Infection potential of submerged propagules was assayed on Schistocerca gregaria. Second-instar larvae fed for 48 h on fresh wheat previously contaminated by a spraying suspension of each inoculum titrated at 10⁷ propagules ml^-1. All seven media produced submerged propagules that were highly infectious for S. gregaria larvae. Shake flask culture assays permitted us to select three low-costmedia, Adamek, Jenkins–Prior, and Catroux for improving scale-up of liquid fermentation focused on mass-production of Metarhizium propagules for mycoinsecticides devoted to locust control. This revised version was published online in June 2006 with corrections to the Cover Date.     

Interactive effects of solutes, potassium sorbate and incubation temperature on growth, heat resistance and tolerance to freezing of Zygosaccharomyces rouxii

The interactive effects of solutes, potassium sorbate and incubation temperature on growth, heat resistance and tolerance to freezing of Zygosaccharomyces rouxii were investigated. Growth rates in media supplemented with glucose, sucrose or NaCl to a _w 0.93 were more rapid than in unsupplemented media ( a _w 0.99). Although growth in unsupplemented medium was lower at 35°C, incubation at 21°C or 35°C had little effect on growth in media supplemented with glucose and sucrose. The addition of 300 μg potassium sorbate/ml to media resulted in reduced growth rates, particularly at 35°C. Heat resistance of Z. rouxii was substantially greater in cultures previously incubated at 35°C than in cultures incubated at 21° in media both with and without 300 μg potassium sorbate/ml. Zygosaccharomyces rouxii was tolerant to freezing at - 18°C for up to 120 d in all test media supplemented with glucose, sucrose or NaCl. The addition of 300 μg potassium sorbate/ml to sucrose-supplemented media resulted in increased resistance to freezing in cultures previously incubated at 21°C. Sensitivity to freezing increased when cultures were incubated at 21°C in media not supplemented with solutes. Glucose and sucrose provided the best protection against inactivation by heating and freezing, regardless of the presence of potassium sorbate in growth media.     

Effect of arachidonic acid,fatty acids,prostaglandins, and leukotrienes on volume regulation in Ehrlich ascites tumor cells

Summary Arachidonic acid inhibits the cell shrinkage observed in Ehrlich ascites tumor cells during regulatory volume decrease (RVD) or after addition of the Ca ionophore A23187 plus Ca. In Na-containing media, arachidonic acid increases cellular Na uptake under isotonic as well as under hypotonic conditions. Arachidonic acid also inhibits KCl and water loss following swelling in Na-free, hypotonic media even when a high K conductance has been ensured by addition of gramicidin. In isotonic, Na-free medium arachidonic acid inhibits A23187 + Ca-induced cell shrinkage in the absence but not in the presence of gramicidin. It is proposed that inhibition of RVD in hypotonic media by arachidonic acid is caused by reduction in the volume-induced Cl and K permeabilities as well as by an increase in Na permeability and that reduction in A23187 + Ca-induced cell shrinkage is due to a reduction in K permeability and an increase in Na permeability. The A23187 + Ca-activated Cl permeability in unaffected by arachidonic acid. PGE₂ inhibits RVD in Na-containing, hypotonic media but not in Na-free, hypotonic media, indicating a PGE₂-induced Na uptake. PGE₂ has no effect on the volume-activated K and Cl permeabilities. LTB₄, LTC₄ and LTE₄ inhibit RVD insignificantly in hypotonically swollen cells. LTD₄, more-over, induces cell shrinkage in steady-state cells and accelerates the RVD following hypotonic exposure. The effect of LTD₄ even reflects a stimulating effect on K and Cl transport pathways. Thus none of the leukotrienes show the inhibitory effect found for arachidonic acid on the K and Cl permeabilities. The RVD response in hypotonic, Na-free media is, on the other hand, also inhibited by addition of the unsaturated oleic, linoleic, linolenic and palmitoleic acid, even in the presence of the cationophor gramicidin. The saturated arachidic and stearic acid had no effect on RVD. It is, therefore, suggested that a minor part of the inhibitory effect of arachidonic acid on RVD in Na-containing media is via an increased synthesis of prostaglandins and that the major part of the arachidonic acid effect on RVD in Na-free media, and most probably also in Na-containing media, is due to the inhibition of the volume-induced K and Cl transport pathways, caused by a nonspecific detergent effect of an unsaturated fatty acid.     

Introduction: gender,migration and the media

Abstract

Mediated representations of gender, ethnicity and migration play an increasingly important role in the way these categories are understood in the public sphere and the private realm. As media often intervene in processes of individual and institutional communication, they provide frameworks for the production and consumption of representations of these categories. Thus media – in their production, representations and consumption – need to be analysed, not only as reflections as pre-existing socio-political realities, but also as constitutive elements in the production of meanings of the self and the Other. This special issue includes a number of articles that examine the articulations of gendered ethnic identities and of gendered citizenship as these are shaped in media production, media representations and media consumption.     

Increased production of withanolide A, withanone, and withaferin A in hairy root cultures of Withania somnifera (L.) Dunal elicited with methyl jasmonate and salicylic acid

The utility of hairy root cultures to produce valuable phytochemicals could be improved by repartitioning more of the desired phytochemical into the spent culture media, thereby simplifying the bioprocess engineering associated with the purification of the desired phytochemical. The majority of nicotine produced by tobacco hairy root cultures is retained within roots, with lesser amounts exuded into the spent culture media. Reduced expression of the tobacco nicotine uptake permease (NUP1) results in significantly more nicotine accumulating in the media. Thus, NUP1-reduced expression lines provide a genetic means to repartition more nicotine into the culture media. The present study examined a wild type and a NUP1-reduced expression hairy root line during a variety of treatments to identify culture conditions that increased nicotine accumulation in the media. The NUP1-reduced expression line grew faster, used less oxygen, and exuded more nicotine into the media. Basification of the culture media associated with root growth resulted in a dramatic reduction in nicotine accumulation levels in the media, which was reversed by decreasing the pH of the media. Kinetic analysis of hairy root growth and nicotine accumulation in the media revealed a potential improvement in nicotine yields in the media by stimulating the branching of tobacco hairy roots.     

Migration,clogging, and carbon source release of nano emulsified vegetable oil in porous media,evaluated by column experiments

To effectively solve the problem of aquifer clogging in the process of in situ bioremediation of groundwater pollution by micron emulsified vegetable oil (Micron EVO), Nano emulsified vegetable oil (Nano EVO) was prepared to replace conventional micron EVO, and three one-dimensional laboratory columns packed with medium or fine sands were conducted to simulate migration, clogging, and carbon source release of EVO in porous media. Column experiment results show that micron and nano EVO resulted in a 20.40% and 3.20% reduction in permeability of medium sand, respectively. Correspondingly, the interception of micron and nano EVO in medium sand were 28.51% and 20.15%, respectively. Obviously, EVO interception is an important reason for permeability loss, and reducing EVO droplet size can effectively alleviate permeability loss in porous media. The COD ratios (dissolved COD/total COD) of micron and nano EVO in medium sand were 87.61% and 61.95%, respectively. The release effect of nano EVO was better than that of micron EVO. Effective longevity of micron and nano EVO were 243.17 d and 98.80 d, respectively. The effect of fine sand media on EVO indicated nano EVO can be used in a finer granular media, and its longevity can also be extended in this media.     

Needless Retesting of Quality-Assured, Commercially Prepared Culture Media

Current revival of interest in quality control of bacteriological culture media prompted this laboratory to develop and implement a system of quality control testing of media purchased from commercial manufacturers. During 8 months we tested more than 900 lots of 46 different media representing 350,000 units of culture media purchased from two major and one minor supplier(s). Only 17 lots were found to be unsatisfactory. This experience raised a question about the real necessity for extensive retesting by users of commercially prepared, quality-assured media. It is suggested that primary responsibility for quality control be placed on the relatively few manufacturer-vendors rather than on the multiple purchaser-users, who may not possess either the expertise or the resources for quality control programs.     

Listeria monocytogenes L Forms I. Induction, Maintenance, and Biological Characteristics

L forms were induced from 15 of 16 strains of Listeria monocytogenes on penicillin gradient plates incubated under aerobic conditions. The culture medium for maintenance of these L forms must contain an electrolyte in a concentration of 1% or sucrose in a concentration of 10%. The electrolytes NaCl, KCl, or MgSO(4) were used in both induction and maintenance media. Induction of L forms occurred more rapidly on media containing KCl. Listeria L forms had the same fermentation reactions as the parent bacterium. The L-form growth in liquid medium was slow, not extensive, and appeared as clumps on the bottom of culture tubes. The morphology of Listeria L forms was similar to that reported for other bacterial L forms. The L forms derived from strain 10403, serotype 1, were stable after two or more passages on penicillin media. They did not revert to the bacterial form after 40 subcultures on penicillin-free media. Some L-form colonies derived from strain 10403 did revert to the bacterial form when transferred directly from induction plates to penicillin-free media. Studies of the growth characteristics for L forms derived from strain 10403 gave the following results: an optimal temperature of 30 C, high electrolyte or sucrose concentration necessary for induction and maintenance, and no requirement for serum.