scholarly journals Intersexual Partial Diploids of Phycomyces

Genetics ◽  
2001 ◽  
Vol 158 (2) ◽  
pp. 635-641
Author(s):  
Bina J Mehta ◽  
Enrique Cerdá-Olmedo
Keyword(s):  
Dry Mass ◽  
Sexual Cycle ◽  
Genetic Constitution ◽  
Phycomyces Blakesleeanus ◽  
Carotene Content ◽  
Sexual Interaction ◽  
Sexual Stimulation ◽  
Nuclear Composition ◽  
Opposite Sex ◽  
Β Carotene

Abstract Sexual interaction between strains of opposite sex in many fungi of the order Mucorales modifies hyphal morphology and increases the carotene content. The progeny of crosses of Phycomyces blakesleeanus usually include a small proportion of anomalous segregants that show these signs of sexual stimulation without a partner. We have analyzed the genetic constitution of such segregants from crosses that involved a carF mutation for overaccumulation of β-carotene and other markers. The new strains were diploids or partial diploids heterozygous for the sex markers. Diploidy was unknown in this fungus and in the Zygomycetes. Random chromosome losses during the vegetative growth of the diploid led to heterokaryosis in the coenocytic mycelia and eventually to sectors of various tints and mating behavior. The changes in the nuclear composition of the mycelia could be followed by selecting for individual nuclei. The results impose a reinterpretation of the sexual cycle of Phycomyces. Some of the intersexual strains that carried the carF mutation contained 25 mg β-carotene per gram of dry mass and were sufficiently stable for practical use in carotene production.

scholarly journals Mutants and Intersexual Heterokaryons of Blakeslea trispora for Production of β-Carotene and Lycopene

2003 ◽  
Vol 69 (7) ◽  
pp. 4043-4048 ◽  
Author(s):  
Bina J. Mehta ◽  
Irina N. Obraztsova ◽  
Enrique Cerdá-Olmedo
Keyword(s):  
Industrial Production ◽  
Main Product ◽  
Dry Mass ◽  
Blakeslea Trispora ◽  
Standard Laboratory ◽  
Carotene Content ◽  
Laboratory Conditions ◽  
Wild Strains ◽  
Opposite Sex ◽  
Β Carotene

ABSTRACT The industrial production of β-carotene with the zygomycete Blakeslea trispora involves the joint cultivation of mycelia of opposite sex in the presence of β-ionone and other chemical activators. We have obtained improved strains by mutation and heterokaryosis. We chose wild strains on the basis of their growth and carotene content in single and mated cultures. Following exposure of their spores to N-methyl-N′-nitro-N-nitrosoguanidine, we obtained high-carotene mutants, which were more productive than their parents but similar to them in having β-carotene as the main product. Further increases in carotene content were obtained after a new round of mutagenesis in one of the mutants. The production was shifted to lycopene in cultures incubated in the presence of nicotine and in lycopene-rich mutants derived from the wild strains. The highest production levels were achieved in intersexual heterokaryons, which contained mutant nuclei of opposite sex. These contained up to 39 mg of β-carotene or 15 mg of lycopene per g (dry mass) under standard laboratory conditions in which the original wild strains contained about 0.3 mg of β-carotene per g (dry mass). β-Ionone did not increase the carotene content of these strains. Not all wild strains lent themselves to these improvements, either because they produced few mutants or because they did not increase their carotene production in mated cultures.

scholarly journals Modification of Sexual Development and Carotene Production by Acetate and Other Small Carboxylic Acids in Blakeslea trispora and Phycomyces blakesleeanus

2006 ◽  
Vol 72 (7) ◽  
pp. 4917-4922 ◽  
Author(s):  
Vera Kuzina ◽  
Enrique Cerdá-Olmedo
Keyword(s):  
Carboxylic Acids ◽  
Sexual Development ◽  
Minimal Medium ◽  
Sexual Cycle ◽  
Blakeslea Trispora ◽  
Common Mechanism ◽  
Maximal Effect ◽  
Phycomyces Blakesleeanus ◽  
Sexual Interaction ◽  
Solid Substrates

ABSTRACT In Phycomyces blakesleeanus and Blakeslea trispora (order Mucorales, class Zygomycetes), sexual interaction on solid substrates leads to zygospore development and to increased carotene production (sexual carotenogenesis). Addition of small quantities of acetate, propionate, lactate, or leucine to mated cultures on minimal medium stimulated zygospore production and inhibited sexual carotenogenesis in both Phycomyces and Blakeslea. In Blakeslea, the threshold acetate concentration was <1 mmol/liter for both effects, and the concentrations that had one-half of the maximal effect were <2 mmol/liter for carotenogenesis and >7 mmol/liter for zygosporogenesis. The effects on Phycomyces were similar, but the concentrations of acetate had to be multiplied by ca. 3 to obtain the same results. Inhibition of sexual carotenogenesis by acetate occurred normally in Phycomyces mutants that cannot use acetate as a carbon source and in mutants whose dormant spores cannot be activated by acetate. Small carboxylic acids may be signals that, independent of their ability to trigger spore germination in Phycomyces, modify metabolism and development during the sexual cycle of Phycomyces and Blakeslea, uncoupling two processes that were thought to be linked and mediated by a common mechanism.

A study on the vitamin A activity of carotene in green fodder

1946 ◽  
Vol 36 (2) ◽  
pp. 95-99 ◽  
Author(s):  
B. C. Ray Sarkar ◽  
K. C. Sen
Keyword(s):  
Vitamin A ◽  
Relative Efficiency ◽  
Chemical Method ◽  
Plant Tissues ◽  
Carotene Content ◽  
A Value ◽  
Green Fodder ◽  
Biological Tests ◽  
Different Sources ◽  
Β Carotene

1. With the object of determining the vitamin A value of carotene in different green fodders, an investigation has been undertaken to study (i) the relation between the chemically determined carotene and its biological activity as compared with that of standard carotene, (ii) the purity of apparent carotene from different sources, (iii) absorption of carotene in rats, and (iv) the relative efficiency of the standard carotene and preformed vitamin A.2. Biological tests have shown that the chemical method of assay is a fair index of the true carotene content in green fodders, and carotene in the form of an extract is quite as effective in the system as that present in the plant tissues. β-Carotene appears to be predominant in these materials.

Lutein and β-carotene content of green leafy Brassica species grown under different conditions

LWT ◽  
2013 ◽  
Vol 53 (1) ◽  
pp. 378-381 ◽  
Author(s):  
Constance Reif ◽  
Eva Arrigoni ◽  
Florence Berger ◽  
Daniel Baumgartner ◽  
Laura Nyström
Keyword(s):  
Brassica Species ◽  
Carotene Content ◽  
Β Carotene

scholarly journals Climate Change Enhanced Carotenoid Pro-Vitamin A Levels of Selected Plantain Cultivars

Plants ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 541 ◽  
Author(s):  
Beloved Mensah Dzomeku ◽  
Julian P. Wald ◽  
Jens Norbert Wünsche ◽  
Donatus Nohr ◽  
Hans K. Biesalski
Keyword(s):  
Low Cost ◽  
Dry Season ◽  
Provitamin A ◽  
Poor People ◽  
Carotene Content ◽  
Uv Index ◽  
Provitamin A Carotenoids ◽  
Micronutrient Intake ◽  
Freeze Dried ◽  
Β Carotene

Diet diversification and the exploitation of traditional, micronutrient-rich germplasm of staple crops are generally regarded as sustainable and low-cost approaches to increase the micronutrient intake of resource-poor people. Sun’s UV index was collected daily throughout the year. The study assessed the seasonality of provitamin A carotenoids in three plantain cultivars in response to climatic condition. Fruits were harvested at three maturities and freeze-dried before analysis. The results showed that there were high levels of the sun’s UV-B radiations throughout the year with the highest occurring from November to May when the area experienced clear skies with minimal cloud cover. These high levels of the sun’s UV-B index occurred between 9.00 h GMT and 17.00 h GMT. The study also showed that α-carotene content increased with maturity in “Apantu” during the rainy seasons ranging from 95 to 172 μg/100 g of dry pulp. Similar trends were observed during the dry season with a range of 28 to 489 μg/100 g. The α-carotene contents were very high in the periods of high sun’s UV-B radiations compared to the periods of low sun’s UV-B radiations. The α-carotene levels in the giant French plantains showed similar trends. Intermediate French “Oniaba” and False Horn “Apantu” plantain cultivar showed the highest content of β-carotene during the dry season. The high provitamin A carotenoid levels in the cultivars coincided with the high levels of the sun’s UV index.

scholarly journals Characterization of crtRB1 Gene Polymorphism and β-Carotene Content in Maize Landraces Originated From North Eastern Himalayan Region (NEHR) of India

2020 ◽  
Vol 4 ◽  
Author(s):  
Senthil Natesan ◽  
Thangjam Surchandra Singh ◽  
Thirusenduraselvi Duraisamy ◽  
Neelima Chandrasekharan ◽  
Sarankumar Chandran ◽  
...  
Keyword(s):  
Gene Polymorphism ◽  
Himalayan Region ◽  
Carotene Content ◽  
North Eastern ◽  
Maize Landraces ◽  
Eastern Himalayan Region ◽  
Β Carotene

scholarly journals Yield and Quality Characteristics of Brassica Microgreens as Affected by the NH4:NO3 Molar Ratio and Strength of the Nutrient Solution

Foods ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 677 ◽  
Author(s):  
Onofrio Davide Palmitessa ◽  
Massimiliano Renna ◽  
Pasquale Crupi ◽  
Angelo Lovece ◽  
Filomena Corbo ◽  
...  
Keyword(s):  
Nutrient Solution ◽  
Inorganic Ions ◽  
Molar Ratio ◽  
High Yield ◽  
Nitrate Content ◽  
Carotene Content ◽  
Molar Ratios ◽  
Half Strength ◽  
Nutrient Solutions ◽  
Β Carotene

Microgreens are gaining more and more interest, but little information is available on the effects of the chemical composition of the nutrient solution on the microgreen yield. In this study, three Brassica genotypes (B. oleracea var. italica, B. oleracea var. botrytis, and Brassica rapa L. subsp. sylvestris L. Janch. var. esculenta Hort) were fertigated with three modified strength Hoagland nutrient solutions (1/2, 1/4, and 1/8 strength) or with three modified half-strength Hoagland nutrient solutions with three different NH4:NO3 molar ratios (5:95, 15:85, and 25:75). Microgreen yields and content of inorganic ions, dietary fiber, proteins, α-tocopherol, and β-carotene were evaluated. Micro cauliflower showed the highest yield, as well as a higher content of mineral elements and α-tocopherol (10.4 mg 100 g−1 fresh weight (FW)) than other genotypes. The use of nutrient solution at half strength gave both a high yield (0.23 g cm−2) and a desirable seedling height. By changing the NH4:NO3 molar ratio in the nutrient solution, no differences were found on yield and growing parameters, although the highest β-carotene content (6.3 mg 100 g−1 FW) was found by using a NH4:NO3 molar ratio of 25:75. The lowest nitrate content (on average 6.8 g 100 g−1 dry weight) was found in micro broccoli and micro broccoli raab by using a nutrient solution with NH4:NO3 molar ratios of 25:75 and 5:95, respectively. Micro cauliflower fertigated with a NH4:NO3 molar ratio of 25:75 showed the highest dry matter (9.8 g 100 g−1 FW) and protein content (4.2 g 100 g−1 FW).

A Method of Obtaining Pure Radioactive β-Carotene Using Phycomyces Blakesleeanus

Mycologia ◽  
1958 ◽  
Vol 50 (6) ◽  
pp. 862-873
Author(s):  
Virgil Greene Lilly ◽  
H. L. Barnett ◽  
R. F. Krause ◽  
F. J. Lotspeich
Keyword(s):  
Phycomyces Blakesleeanus ◽  
Β Carotene
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