Biotechnology
M. Yahyazadeh; N. Hadi; Z. Shirazi; K. Jaimand; Kh. Karimzadeh Asl; M. Makizadeh Tafti; S. Fekri Qomi; M. Rahimifard; M. Gorji; F. Askari; Z. Behrad; D. Selmar
Abstract
Plants are the main sources of secondary metabolites with high medical value. The most important member of these valuable compounds are alkaloids with the different drug purposes. Concerning the limited production of some of these metabolites in the plants, these medicinal compounds can be produced naturally ...
Read More
Plants are the main sources of secondary metabolites with high medical value. The most important member of these valuable compounds are alkaloids with the different drug purposes. Concerning the limited production of some of these metabolites in the plants, these medicinal compounds can be produced naturally and commercially with the identification and transfer of alkaloids-producing enzymes corresponding plant genes to the microorganisms as an alternative method. In this way, the characterization of the corresponding genes is the first step. Among the different enzymes involved in the alkaloid biosynthesis, the cytochrome P450 enzymes play an important role. Due to the endoplasmic reticulum (ER) localization of these enzymes and their glycoprotein characters, they cannot be expressed functionally in the standard bacterial systems. Consequently, the heterologous expression aimed to verify the enzymatic activity can favorably be performed using the eukaryotic systems, like yeast or insect cells. Herein, in this study, with employing a phylogenic comparison of cheilanthifoline synthase sequence of Eschscholzia californica Cham. and comparing the sequence with the homolog amino acid sequences of Chelidonium majus L. achieved from bioinformatics databases, six cytochrome P450 enzymes responsible for cheilanthifoline synthase in Ch. majus were identified. To prove the efficacy of these enzymes practically, their genes were cloned into the pPIC3.5 vector. Then, these recombinant vectors were transferred to the yeast cell (Pichia pastoris) and the scoulerine alkaloid was given to its media. Finally, the cheilanthifoline alkaloid microbial production by P. pastoris containing the recombinant plasmids was evaluated by LC-MS. The results of the present study indicated that among the enzymes genes cloned and introduced to the yeast host, only the Contig8931 enzyme had the cheilanthifoline synthase activity.
M.H. Lebaschi; E. Sharifi Ashourabadi; M. Makizadeh Tafti; A.H. Talebpour; J. Hasani; Kh. Karimzadeh; S. Asadi sanam
Abstract
In order to study the effect of plant density on some quantitative and qualitative characteristics of Thymus pubescens Boiss. & Kotschy ex Celak under rainfed conditions, a field experiment was conducted in a randomized complete block design with three replications in three different dry farming ...
Read More
In order to study the effect of plant density on some quantitative and qualitative characteristics of Thymus pubescens Boiss. & Kotschy ex Celak under rainfed conditions, a field experiment was conducted in a randomized complete block design with three replications in three different dry farming regions of the country during two years. Experimental treatments consisted of plant density (25, 35 and 50 cm between plants on rows equal to 8, 6 and 4 plant/m2, respectively), time (first and second year after planting) and location (East Azarbayjan, Kordestan, and Tehran). The traits including plant height, canopy diameter, dry matter yield of aerial parts, essential oil yield and content were measured at full flowering stage. The results of ANOVA indicated the significant effect of density, location and time and their interaction on all traits studied. The highest dry matter yield (1147 kg ha-1) was obtained in both two years in Tehran at 8 plant/m2. Kordestan with 2.25% and East Azarbayjan with 0.43% had the highest and lowest essential oil percentage, respectively. In density × location interaction, the highest amount of essential oil yield was obtained in Kordestan (21.73 kg ha-1) and Tehran (17.88 kg ha-1) at a density of 8 plant/m2. Thymus pubescens showed higher dry matter and essential oil yield under high plant density, indicating the establishment and adaptation of the species to different rainfed regions of the country especially Damavand and Kordestan.
Kh. Karimzadeh; F. Sefidkon; N. Majnoon Hosseini; S.A. Peighambari
Abstract
To study the effect of different levels of soil moisture, zeolite and biofertilizers on physiological characteristics, yield and essential oil of medicinal plant Dracocephalum moldavica L., this research was performed in 2010 at Tehran university research greenhouse. For this purpose, a factorial split-plot ...
Read More
To study the effect of different levels of soil moisture, zeolite and biofertilizers on physiological characteristics, yield and essential oil of medicinal plant Dracocephalum moldavica L., this research was performed in 2010 at Tehran university research greenhouse. For this purpose, a factorial split-plot experiment in RCBD with 4 replications was used. In this study the main plots included different soil moisture levels (90%, 60% and 30 % FC) and subplots consisted of two levels of zeolite (zero, 8gr 4kg-1 soil) along with four levels of biofertilizers (without biofertilizer, nitroxin, biphosphorous, nitroxin+biphosphorous). Results showed that the highest amount of total, a and b chlorophylls, relative water content and yield of essential oil were obtained through %90 FC, but the highest amount of solution carbohydrates, proline and percentage of essential oil were obtained through %30 FC. The maximum amount of studied physiological traits as essential oil percentage and essential oil yield were obtained from application of nitroxin+biophosphorous. Interaction effects of soil moisture, zeolite and biofertilizers showed significant differences among different treatments on amount of a, b and total chlorophyll, relative water content, percentage and yield of essential oil. The maximum amount of oil yields were obtained from zeolite application and combination of nitroxin+biphosphorous and 60% FC and treatment of no consumption of zeolite and combination of nitroxin+biphosphorous with 90% FC. It could be concluded that moderate drought stress (60% FC) with application of zeolite and combination of nitroxin+biphosphorous is beneficial for Dragonhead essential oil yield.