AN IMPROVED CULTURE-MEDIUM FOR DETECTING LIVE YEAST PHASE CELLS OF PARACOCCIDIOIDES-BRASILIENSIS

The plating efficiency of standard mycological media such as brain heart infusion (BHI) agar is poor for Paracoccidioides brasiliensis. We prepared a water-extract of yeast phase cells of P. brasiliensis and examined it for growth-enhancing activity for the fungus. The water-extract, when added to BHI agar to a concentration of 5%, improved the plating efficiency of the medium for the fungus to some extent, but the degree of improvement was considerably varied among P. brasiliensis isolates. By contrast, when the water-extract was added in combination with horse serum (4%), the plating efficiency was highly improved (to 94-99%) for all the P. brasiliensis isolates employed. The growth-enhancing factor(s) in the water-extract was heat-stable and heating at 120-degrees-C for 15 min had little, if any, effect on growth-enhancing activity.

Interaction in culture medium of acttnomycetes and native fungi wtth rhizobia that form nodules in Neonotonia wighth lackley (perennial soybean)

The relationship between soil fungi and actinomycetes, with rhizobia that produce nodulation in Neonotonia wightii (perennial soybean) was studied in culture medium in order to obtain material to be used in mixed inoculations of this legume. A field experiment was designed to provide soil samples and isolate microorganisms belonging to these groups that are capable of interfering in the development of two selected rhizobium strains. Results show that the Bradyrhizobium strains used in the experiment, which are efficient in nodulation of Neonotonia wightii, are highly sensitive to substances produced in the culture medium by actinomycetes and fungi.

Semi-selective culture medium for Xanthomonas axonopodis pv. malvacearum detection in cotton seeds (Gossypium hirsutum L.)

The cotton disease known as angular leaf spot, caused by Xanthomonas axonopodis pv. malvacearum (Xam) has been causing cotton losses in several producing regions around the world. Xam is transmitted by seeds, which may be infected both externally and internally. Infected seeds constitute the main long-distance dissemination mode of the pathogen. In view of this, the use of healthy seeds is a must. To accomplish that, detection methodologies for the bacteria must be developed be used in seed health analysis laboratories. This study aimed to develop a semi-selective medium for Xam detection in cotton seeds. The semi-selective culture medium was named MSSXAN and it was consisted of peptone (5.0 g), beef extract (3 g), sucrose (5 g), soluble starch (10 g), agar (15 g), CaCl 2 (0.25 g), Tween 80 (10 mL), distilled water (1,000 mL), crystal violet solution at 1% (150 μL), cephalexin (50 mg 1*), methyl thyophanate (10 mg*) and chlorothalonil (10 mg*) - *added after culture medium autoclaving. This MSSXAN medium shows low repressiveness to Xam and it be used for isolation of this bacteria in cotton seeds health analysis. © 2009 Academic Journals Inc.

Pulp fruit added to culture medium for in vitro orchid development

As an additive in in vitro culture media, fruits have a great potential for facilitating economical orchid production because of lower technology requirements and the ease of obtaining raw materials to formulate culture media. We studied the in vitro growth of Cattleya bicolor Lindl. grown in a simplified culture medium supplemented with different kinds of fruit pulp. The experimental design was completely randomised, with eight seedlings per replication and ten replications per treatment, for a total of 80 seedlings per treatment. The culture medium was made using 150 g L -1 of pulp (without peel or seed) from the following fruits: ripe Santa Cruz tomatoes (Solanum lycopersicum L.), dwarf bananas (Musa cavendishii L.) of intermediate ripeness, light green chayote (Sechium edule (Jacq.) Sw), ripe papaya (Carica papaya L.) or green coconut (Cocos nucifera L.).The treatment control was MS 50 %. The treatments and the control were kept in a growth chamber for seven months before evaluating seedling survival percentage, shoot height, number of leaves, rooting percentage, root number, root length and dry masses of shoot and roots. The highest percentages of seedling survival were obtained using MS 50 %, banana and coconut medium. The seedling survival and rooting percentages illustrate that it is possible to emphasise the culture medium MS 50% and the culture medium supplemented with coconut on the most traditional culture medium with banana or tomato pulp. For the in vitro development of Cattleya bicolor Lindl., a simplified culture medium supplemented with coconut pulp is the most suitable for use as an alternative to MS 50%. A simplified culture medium supplemented with papaya pulp is not recommended for the in vitro development of Cattleya bicolor Lindl.

Assessing melatonin and its oxidative metabolites amounts in biological fluid and culture medium by liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Inorganic elemental analysis and identification of residual monomers released from different glass ionomer cements in cell culture medium

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Micropropagation of gerbera using chlorine dioxide (ClO2) to sterilize the culture medium

One of the alternatives to autoclaving culture media is chemical sterilization, which may cause fewer changes to the chemical composition of the media. In this study, the effect of chemical sterilization by inclusion of chlorine dioxide (ClO2) in the culture medium on the in vitro development of gerbera (Gerbera jamesonii) cv. AL101, cultured at different stages of micropropagation, was evaluated. The following five concentrations of ClO2 were tested: 0%, 0.0025%, 0.0050%, 0.0075%, and 0.010%. Autoclaved medium was used as the control. ClO2 in the culture medium reduced contamination at rates comparable to autoclaving when tested at three stages of the culture process: in vitro establishment, multiplication, and rooting. Plantlets grown in culture media sterilized with ClO2 showed similar or better development than those grown in autoclaved culture medium. Use of 0.0025% ClO2 to sterilize the culture medium resulted in better plantlet development than autoclaved medium, regardless of the stage of micropropagation.

Culture medium of diluted skimmed milk for the production of nisin in batch cultivations

Nisin is a promising alternative to chemical preservatives for use as a natural biopreservative in foods. This bacteriocin has also potential biomedical applications. Lactic acid bacteria are commonly cultivated in expensive standard complex media. We have evaluated the cell growth and nisin production of Lactococcus lactis in a low-cost natural medium consisting of diluted skimmed milk in a 2-L bioreactor. The assays were performed at 30 degrees C for 56 h, at varying agitation speeds and airflow rates: (1) 200 rpm (no airflow, and airflow at 0.5, 1.0 and 2.0 L/min); (2) 100 rpm (no airflow, and airflow at 0.5 L/min). Nisin activity was evaluated using agar diffusion assays. The highest nisin concentration, 49.88 mg/L (3.3 log AU/mL or 1,995.29 AU/mL), was obtained at 16 h of culture, 200 rpm and no airflow (k(L)a = 5.29 x 10(-3)). These results show that a cultivation medium composed of diluted skimmed milk supports cell growth to facilitate nisin biosynthesis.

Chiral HPLC analysis of donepezil, 5-O-desmethyl donepezil and 6-O-desmethyl donepezil in culture medium: application to fungal biotransformation studies

An high performance liquid chromatography (HPLC) method for the enantioselective determination of donepezil (DPZ), 5-O-desmethyl donepezil (5-ODD), and 6-O-desmethyl donepezil (6-ODD) in Czapek culture medium to be applied to biotransformation studies with fungi is described for the first time. The HPLC analysis was carried out using a Chiralpak AD-H column with hexane/ethanol/methanol (75:20:5, v/v/v) plus 0.3 % triethylamine as mobile phase and UV detection at 270 nm. Sample preparation was carried out by liquid-liquid extraction using ethyl acetate as extractor solvent. The method was linear over the concentration range of 100-10,000 ng mL(-1) for each enantiomer of DPZ (r a parts per thousand yenaEuro parts per thousand 0.9985) and of 100-5,000 ng mL(-1) for each enantiomer of 5-ODD (r a parts per thousand yenaEuro parts per thousand 0.9977) and 6-ODD (r a parts per thousand yenaEuro parts per thousand 0.9951). Within-day and between-day precision and accuracy evaluated by relative standard deviations and relative errors, respectively, were lower than 15 % for all analytes. The validated method was used to assess DPZ biotransformation by the fungi Beauveria bassiana American Type Culture Collection (ATCC) 7159 and Cunninghamella elegans ATCC 10028B. Using the fungus B. bassiana ATCC 7159, a predominant formation of (R)-5-ODD was observed while for the fungus C. elegans ATCC 10028B, DPZ was biotransformed to (R)-6-ODD with an enantiomeric excess of 100 %.

Sample preparation of culture medium from Madin-Darby canine kidney cells

A reproducible, standardized and simple sample preparation methodology is the key to successful two-dimensional gel electrophoresis (2-DE). This chapter describes step-by-step the sample preparation of culture medium from Madin-Darby canine kidney (MDCK) cells. Tips and tricks are given to circumvent possible pitfalls.

Human bone chips release of sclerostin and FGF-23 into the culture medium: an in vitro pilot study

Abstract OBJECTIVE: Signaling molecules derived from osteocytes have been proposed as a mechanism by which autografts contribute to bone regeneration. However, there have been no studies that determined the role of osteocytes in bone grafts. MATERIAL AND METHOD: Herein, it was examined whether bone chips and demineralized bone matrix release sclerostin and FGF-23, both of which are highly expressed by osteocytes. RESULTS: Bone grafts from seven donors were placed in culture medium. Immunoassay showed that bone chips released sclerostin (median 1.0 ng/ml) and FGF-23 (median 9.8 relative units/ml) within the first day, with declining levels overtime. Demineralized bone matrix also released detectable amounts of sclerostin into culture medium, while FGF-23 remained close to the detection limit. In vitro expanded isolated bone cells failed to release detectable amounts of sclerostin and FGF-23. CONCLUSION: These results suggest that autografts but also demineralized bone matrix can release signaling molecules that are characteristically produced by osteocytes. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. KEYWORDS: FGF-23; autologous bone; bone grafts; demineralized bone matrix; osteocytes; sclerostin