Basidiocarps, annelloconidia, and sclerotia in agar cultures of Pistillaria (Clavariadelphaceae)

1971 ◽  
Vol 49 (5) ◽  
pp. 695-697 ◽  
Author(s):  
Richard E. Koske Jr. ◽  
Peter W. Perrin
Keyword(s):  
Fruit Body ◽  
Pigment Production ◽  
Taxonomic Significance ◽  
Agar Culture ◽  
Conidium Formation ◽  
Temperature Optima

Pistillaria micans Fr. and Pistillaria setipes Grev. produced fertile sporophores in agar culture. Light was necessary for production of fertile basidiocarps in both species and for pigment production and conidium formation in P. micans. Annelloconidia were produced by P. micans. Viable sclerotia were formed by P. setipes. The taxonomic significance of sclerotia in Pistillaria and Typhula is discussed. Neither species demonstrated geotropism, but the fruit body of P. setipes was positively phototropic. Temperature optima for growth and sporophore production were ca. 15 °C for P. setipes and ca. 20–22 °C for P. micans.

STUDIES OF CANADIAN THELEPHORACEAE: XI. CONIDIUM PRODUCTION IN THE THELEPHORACEAE

1954 ◽  
Vol 32 (1) ◽  
pp. 259-280 ◽  
Author(s):  
Mary Barbara Maxwell
Keyword(s):  
Fruit Body ◽  
Conidium Production ◽  
Conidium Formation ◽  
Bipolar Type

Four species of the Thelephoraceae, Stereum sulcatum Burt, Vararia granulosa (Pers. ex Fries) Laurila, Corticium furfuraceum Bres., and Trechispora raduloides (Karst.) Rog. have been found to produce conidia on both simple-septate, haploid mycelia and clamp-bearing dicaryotic mycelia. The conidia of the first three species are borne on oedocephaloid conidiophores while those of the fourth are formed sympodially. In all four species, the conidia, whether produced on haploid or dicaryotic mycelia, are uninucleate and each germinates to give a simple-septate, haploid mycelium. Interfertility tests were undertaken with monosporous cultures derived from the germination of single conidia or of single basidiospores. By pairing single basidiospore cultures from an individual fruit body of both Stereum sulcatum and Vararia granulosa, it was shown that these species exhibit a bipolar type of interfertility. For each of the species under investigation, complete interfertility was obtained in pairings between single conidium cultures from different isolates of the same species. A series of single conidium cultures for each species, derived from conidia borne on a dicaryotic mycelium, when paired in all possible combinations, fell into two groups on the basis of their ability to produce clamp connections. In S. sulcatum, members of each group of single conidium cultures were interfertile with one or other of the two types of single basidiospore cultures from the same isolate. Cytological studies show that there is no fusion of nuclei prior to conidium formation on the dicaryotic mycelium. Instead, the two nuclei of the dicaryon divide separately to produce approximately equal numbers of each type of nucleus, one of which enters each conidium. As indicated by the interfertility tests, the conidia therefore contain nuclei of two reaction types which are identical with those of the two nuclei of the dicaryon and also with those of the nuclei of the parent basidiospores.

THE INFLUENCE OF ETHANOL ON THE CONVERSION OF PREGNENOLONE TO PROGESTERONE BY HUMAN PLACENTAL MICROSOMES

1974 ◽  
Vol 76 (1) ◽  
pp. 178-188 ◽  
Author(s):  
H. Lübbert ◽  
K. Pollow ◽  
R. Wagner ◽  
J. Hammerstein
Keyword(s):  
Kinetic Parameters ◽  
Enzyme Preparation ◽  
Ethanol Concentration ◽  
Hydroxysteroid Dehydrogenase ◽  
Product Formation ◽  
Linear Increase ◽  
Maximal Velocity ◽  
Microsomal Enzyme ◽  
Temperature Optima ◽  
Substrate Concentrations

ABSTRACT The effects of ethanol on kinetic parameters of placental Δ5-3β-hydroxysteroid dehydrogenase were studied. In the presence of high pregnenolone concentrations (50 μm, [S] > Km) the microsomal enzyme preparation exhibited an almost linear increase in activity as the ethanol concentration in the medium was raised from 2.5 to 15 % (v/v). At lower substrate concentrations ([S] << Km) ethanol caused inhibition. Other effects of ethanol were: linearity of product formation with time was prolonged; the maximal velocity was markedly increased; the Km for pregnenolone slightly decreased with increasing ethanol concentrations (2.5 to 10 %, v/v) whereas the Km for NAD remained the same. The pH and temperature optima of the reaction were unaffected by ethanol. Other organic solvents caused similar effects.

Temperature Dependent Green Synthesis of 3-Carboxycoumarins and 3,4-unsubstituted Coumarins

2019 ◽  
Vol 16 (1) ◽  
pp. 130-135 ◽  
Author(s):  
Jack van Schijndel ◽  
Dennis Molendijk ◽  
Luiz Alberto Canalle ◽  
Erik Theodorus Rump ◽  
Jan Meuldijk
Keyword(s):  
Knoevenagel Condensation ◽  
Ammonium Bicarbonate ◽  
Solvent Free ◽  
Temperature Dependent ◽  
Step Procedure ◽  
Synthetic Routes ◽  
High Yields ◽  
Temperature Optima ◽  
Solvent Free Synthesis ◽  
Full Conversion

Aim and Objective: Because of the low abundance of 3,4-unsubstituted coumarins in plants combined with the complex purification process required, synthetic routes towards 3,4-unsubstituted coumarins are especially valuable. In the present work, we explore the possibilities of a solvent-free Green Knoevenagel condensation on various 2-hydroxybenzaldehyde derivatives and malonic acid without the use of toxic organocatalysts like pyridine and piperidine but only use ammonium bicarbonate as the catalyst. Materials and Methods: To investigate the scope of the Green Knoevenagel condensation for the synthesis of 3,4-unsubstituted coumarins, various 2-hydroxybenzaldehyde derivatives were screened as starting material in the optimized two-step procedure developed for 2-hydroxybenzaldehyde. </P><P> Results: This study shows that the intramolecular esterification and the decarboxylation are in competition, but show different temperature optima. In order to suppress premature decarboxylation and maximize the yield of coumarin, a two-step procedure was adopted. The reaction mixture containing ammonium bicarbonate is initially kept at 90ºC for 1 hour. After completion of the cyclization, the temperature of the reaction mixture is increased to 140ºC for 2 hours. Following this protocol, coumarin could be isolated with a yield of 95%. Conclusion: A two-step procedure for the solvent-free synthesis of several 3,4-unsubstituted coumarins was developed using ammonium bicarbonate, resulting in high yields of the desired products. Moreover, this procedure has a low E-factor and is, therefore an environmental friendly reaction in line with the principles of Green Chemistry. It was shown that by initially capping the temperature at 90ºC, premature decarboxylation can be suppressed. After full conversion to the intermediate 3-carboxycoumarin, the temperature can be increased to 140ºC finalizing the reaction. Ammonium bicarbonate was shown to catalyze both the Green Knoevenagel condensation and the decarboxylation step.

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