Assessment of blackberry varieties suitable for growing in the Right-Bank Forest-Steppe part of Ukraine

2020 ◽  
pp. 201-206
Author(s):  
L. Shubenko ◽  
S. Shokh ◽  
Kumanska Yu.
Keyword(s):  
Crop Yields ◽  
Average Weight ◽  
Forest Steppe ◽  
Maximum Weight ◽  
Yield Level ◽  
High Yields ◽  
The Right ◽  
High Level ◽  
The University

The research aimed to study the productivity of blackberry foreign varieties (Rubus subgenus Rubus Watson) in the Right-Bank Forest-Steppe part of Ukraine as they are attractive for production due to their fruit taste and appearance. The task was to establish the beginning and duration of fruiting of blackberry varieties, to determine the yield level and the quality of the berries. A fi eld experiment was conducted on the experimental fi eld of the Scientific and Research Center of BNAU to assess the productivity of blackberry varieties. The studies were started in the spring of 2017 on blackberry seedlings with growing the culture in vitro in the biotechnological laboratory of the university. The tests included 5 varieties with climbing shoots: Smoothstem, Thornfree, Black Satin, Triple Crown, Arapaho. According to the results of observations, it was found that for two years of fruiting among the studied varieties, the earliest production was received in the Arapaho variety, in the first decade of July. Triple Crown, with the fi rst fruits ripened on August 2, was characterized by late fruiting. The Triple Crown variety diff ered by the longest period of berry coming – 35 days. The yield obtained in a year after planting is not an indicator of long-term crop yields. However, the Triple Crown variety diff ered by the highest yield in the fi rst year of fruiting, with an average of 3.7 kg of berries obtained from a bush. High yields were also observed in the Smoothstem variety. Black Satin variety was characterized by the high level of yield growth for over two years of fruiting, which amounted to 80 %. The largest in the fi rst years of fruiting were Triple Crown fruits with an average weight of 11.1 g. The maximum weight of individual berries of this variety reached 17.7 g. The Arapaho variety also stood out with its large fruits of 8.5 g on average. Some fruits reached a maximum weight of 12.1 g. Key words: blackberry, the beginning of fruiting, productivity, average weight of berries, duration of products supply.

scholarly journals Effectiveness of chemical protection of chickpea crops depending on the effect of different herbicides and seed rates

2020 ◽  
pp. 33-36
Author(s):  
Y. Makuch ◽  
S. Moshkivska ◽  
V. Smih
Keyword(s):  
Stocking Density ◽  
Application Rate ◽  
Cultivated Plants ◽  
Forest Steppe ◽  
Seeding Rate ◽  
Crop Development ◽  
High Yields ◽  
The Right ◽  
High Level ◽  
Favorable Conditions

Goal. Search and evaluate the effectiveness of herbicides and their compositions in chickpea crops. On the basis of research to prepare a comprehensive system of protection of chickpea crops from the presence of weeds, which ensures high yields and is economically and environmentally feasible in the conditions of the Right-bank Forest-Steppe of Ukraine. Methods. The experiments were based on the following scheme: Factor A (weed protection): 1. Net control; 2. Harsh control; 3. Fabian, D.Sc. 0.1 kg/ha; 4. Bazagran, bp — 2.5 l/ha; 5. Reiser, k.e. 2.0 l/ha. Factor B (seeding rate): Seeding rate, thousand pieces / ha —500; 600; 700. Results. One way to increase the competition of chickpea plants with weeds can be to increase the stocking density of cultivated plants. It is also known that the combination of several methods of crop care contributes to the overall increase of their effect. By identifying a critical period of competitive interaction between chickpeas and weeds, it is possible to take action on the latter before they cause significant damage to the crop. Competitive reciprocity and harmfulness of weeds in chickpea crops is observed throughout the entire period of crop development. A significant decrease in productivity is observed in the presence of 10 weed plants per square meter. Increased weed density of up to 25 pc/m2 showed a 23.7% decrease in crop yield. Conclusions. On the basis of the conducted researches it is possible to make a generalization that in the conditions of humus soils of the Right-Bank Forest-Steppe of Ukraine, when applying herbicides on chickpea crops, the best results in weed control were obtained with the introduction of Fabian, dr. application rate of 0.1 kg/ha and Bazagran, pp. 2.5 l/ha. The most favorable conditions of formation of biological productivity and realization of high level of productivity of chickpea plants are observed at the norms of sowing of seeds of 600 thousand pieces/ha.

scholarly journals Potato productivity depending on variety specialties under cultivating in the right-bank Forest-Steppe of Ukraine

2020 ◽  
pp. 120-127
Author(s):  
M. Ostrenko ◽  
L. Pravdyva ◽  
Yu. Fedoruk ◽  
M. Grabovskiy ◽  
S. Pravdyvyi
Keyword(s):  
Animal Feed ◽  
Climatic Conditions ◽  
Raw Material ◽  
Average Weight ◽  
Forest Steppe ◽  
Potato Varieties ◽  
Modern Agriculture ◽  
Abiotic And Biotic Factors ◽  
The Right ◽  
Mass Increase

In terms of geographical distribution and consumption, potatoes occupy one of the leading positions in the structure of food production in Ukraine. It is also used extensively as animal feed. The versatility of use in diff erent sectors of the economy with potatoes cannot be compared to any crop. Potato is of great importance as a raw material for the production of starch, sugar, molasses, alcohol, glucose and etc. A signifi cant reduction in the commodity production of food potatoe in farms is related to the solution a whole complex of important issues, in particular seed production, agro-technology of cultivation, application of highly eff ective pesticides, availability of agricultural machinery and material-technical support. The difficult ecological and energy situation in modern agriculture proves that it is possible to obtain high and stable yields of all crops only if there are varieties in production adapted to diff erent soil and climatic conditions. Variety is one of the important factors of yield stability and fi xed assets of agricultural production. A variety, as a genotype or a set of very close genotypes, exists in a specific environment and, moreover, interacts with it, encountering complex communication, intensity and time of manifestation, abiotic and biotic factors. At the same time, a connection is established between a variety and an environment that infl uences the formation and manifestation of morphological, economic and biological characters. The aim of the research was to study the growth, development and yield of early ripe potato varieties in the rightbank Forest-Steppe of Ukraine. The article presents the results of studies on the cultivation of early ripe varieties of potatoes. Namely, the germination and survival of potato plants was studied, which amounted to 89.5 and 87.3 % in the Skarbnytsa variety, 90.2 and 88.7 % in the Shchedryk variety, and 88.6 and 86.5 % in the Dnipryanka variety; the number of formed stems per plant is calculated, which is 3.3 in the Skarbnytsa variety, 3.6 in the Shchedryk variety and 2.7 in the Dniprianka variety. The dynamics of the mass increase and the fractional composition of potato tubers are shown. On average, during the research, the average weight of tubers from the bush was high for the Shchedryk variety and amounted to 616.2 g, somewhat less than those for the Skarbnytsa (484,5 g) and Dniprianka (397,8 g) varieties. It was established that the Shchedryk variety had the highest potato productivity in the experiment – 250.3 c/ha, in the Skarbnytsa and Dnipryanka varieties, the yield was 210.0 and 201.2 c/ha, respectively. Key words: potato, varieties, plant survival, tubers weight, productivity.

scholarly journals The Pawpaw Research Program at the Horticulture Department of the University of Florence

2003 ◽  
Vol 13 (3) ◽  
pp. 455-457 ◽  
Author(s):  
Elvio Bellini ◽  
Stefania Nin ◽  
Maurizio Cocchi
Keyword(s):  
Fruit Size ◽  
New Variety ◽  
Asimina Triloba ◽  
Postharvest Handling ◽  
Fruit Growing ◽  
New Varieties ◽  
High Yields ◽  
University Of Florence ◽  
The University

The Horticulture Department of the University of Florence has been studying the pawpaw (Asimina triloba) since 1990 through collaboration with Italian fruit grower Domenico Montanari, who currently hosts the largest pawpaw orchard and variety collection in Italy. Research efforts are focused mainly on the development of new varieties and selections with desirable ornamental characteristics. New variety selection is based on high tree productivity, large fruit size, good organoleptic quality and improved fruit postharvest handling. The breeding program has resulted in 3,000 seedlings that are currently being evaluated in Tuscany, Italy. In addition to breeding efforts, 15 commercially available varieties were evaluated in replicated trials in 2000 and 2001, with selections characterized for vegetative, reproductive and pomological traits. In 2000 and 2001, the varieties `Prima 1216' and `Prolific' had high yields and should be suitable for production in Italian fruit-growing areas. Experiments to establish explants of pawpaw in culture were also performed testing a range of genotypes, disinfestation procedures, and methods to induce callus culture. Protocols for the propagation of pawpaw in vitro would offer many advantages for mass multiplication of desirable plants; however, the propagation of pawpaw in vitro has so far been met with limited success.

scholarly journals Agrobiological parameters of various varieties and hybrids of sweet sorghum

2021 ◽  
Vol 17 (3) ◽  
pp. 193-198
Author(s):  
V. V. Liubych ◽  
L. I. Storozhyk ◽  
V. I. Voitovska ◽  
I. S. Tereshchenko ◽  
A. I. Losieva
Keyword(s):  
Sweet Sorghum ◽  
Sugar Content ◽  
Sugar Yield ◽  
Grain Weight ◽  
Forest Steppe ◽  
Sweet Sorghum Juice ◽  
Wide Range ◽  
Individual Productivity ◽  
High Yields ◽  
The Right

Purpose. To reveal the features of agrobiological parameters formation of sweet sorghum various varieties and hybrids in the conditions of the Right-Bank Forest-Steppe of Ukraine. Methods. During 2018–2020 twenty-one varieties and hybrids of sweet sorghum of various ecological and geographical origins (Ukraine, Russia, USA, France, Germany, Hungary, Brazil) were studied in the field. Parameters like plant height and indices of their individual productivity (grain weight per panicle, 1000 grain weight, etc.), yield of dry biomass and grain, content of sugar in juice and protein in grain, as well as estimated sugar and protein yield in a crop. The counts were carried out in the phase of physiological ripeness of the culture. Results. In the group of Ukrainian varieties and hybrids, the plants were from 272 to 306 cm high, in the foreign group – from 274 to 412 cm. Varieties ‘Red Amber’, ‘Sioux’, ‘Affas CJ 899’, ‘Freed’ and ‘Early Orange’ are of high value for breeding practice, their plants were the tallest – from 388 to 412 cm. The panicle length of sweet sorghum cultivars of Ukrainian breeding ranged from 16.0 to 17.3 cm, foreign – from 11.0 to 19.4 cm. Grain weight from one panicle varied from 32.8 to 41.6 g and from 29.2 to 43.5 g, respectively. In a wide range, depending on the varietal characteristics, the indicator of the number of grains per panicle also varied from 1338 to 1708 pcs. The mass of 1000 grains of sweet sorghum ranged from 28.0 to 31.0 g in varieties and hybrids of Ukrainian breeding, in foreign ones – from 19.3 to 31.0 g. The yield of dry vegetative mass of cultivars of Ukrainian breeding was at the level of 8.24–9.11 t/ha. The highest rates were shown in hybrid ‘Mamont’ and ‘Huliver’ variety – 9.05 and 9.11 t/ha, respectively. For cultivars and hybrids of foreign breeding, this indicator varied from 7.00 to 12.17 t/ha. Significantly higher biomass in comparison with the standard variety (‘Sylosne 42’) was produced by ‘Vorai Sumac’, ‘Sorgo Cucre’, ‘Sioux’, ‘Freed’, ‘Red Amber’, ‘Mohavk’, ‘Affas CJ 899’, ‘Early Orange’ – 9.03–12.17 t/ha. The sugar content in sweet sorghum juice varied from 15.2 to 17.2%. The estimated sugar yield in Ukrainian cultivars was at the level of 0.82–0.89 t/ha, in foreign ones – from 0.72 to 1.18 t/ha. In all studied varieties it was the highest in ‘Sorgo Cucre’, ‘Sioux’, ‘Freed’, ‘Red Amber’, ‘Mohavk’, ‘Affas CJ 899’, ‘Early Orange’ – 0.94–1.18 t/ha. Conclusions. The productivity of sweet sorghum varies greatly depending on the origin of the variety and hybrid. In the conditions of the Right-Bank Forest-Steppe, in order to obtain a high sugar yield, it is advisable to grow ‘Sylosne 42’, ‘Favoryt’, ‘Troistyi’, ‘Dovista’, ‘Huliver’ varieties and ‘Ananas’, ‘Medovyi’, ‘Mamont’ hybrids. Varieties ‘Vaconia Orange’, ‘Vorai Sumac’, ‘Sorgo Cucre’ and hybrids ‘Ald Sorghum’, ‘Sioux’, ‘Freed’, ‘Red Amber’, ‘Mohavk’, ‘Affas CJ 899’, ‘Early Orange’ provide high yields of vegetative masses. Hybrids ‘Freed’, ‘Affas CJ 899’ and ‘Early Orange’ produce a large vegetative mass (11.08–12.17 t/ha), grain yield (8.00–8.15 t/ha) and a high protein content (9.8–11.3%).

THE NUTRITION OF ST. VLADIMIR UNIVERSITY STUDENTS

2019 ◽  
pp. 19-28
Author(s):  
Taras Samchuk
Keyword(s):  
University Students ◽  
Student Behavior ◽  
Main Role ◽  
University Administration ◽  
Main Portion ◽  
Side Dishes ◽  
Quality Of Products ◽  
The Right ◽  
High Level ◽  
The University

The article depicts the peculiarities of St. Vladimir University students’ nutrition in the years 1834-1863. The main aim of the research to show how nutrition differentiated among students community and how different types of diet influenced everyday life of them. That’s why the types of nutrition of two main students’ groups (who were educated and maintained by the state and students who studied at their own expense) are analyzed in the article. Special attention is paid to the question of the diet, the peculiarities of the regime, organization, and nutrition value of products for students. For example, budget students had a fixed schedule of eating. Their breakfast started at 7 am. It was only a small loaf and a cup of tea. The students had completely the same dinner at 6 or 7 pm. The main portion of the food they received for a lunch. Typical lunch included primarily liquid food (soup with beetroots, beans, peas, meat or fish), then students received the main dish. Usually, it was roasted meat or fish with potatoes or other side dishes. The university administration hired special servants for questions connected with budget students’ nutrition. The main role of supplying food for students’ table played a provisor. He also hired all staff (cooks, bakers, lackeys), who cooked and served food for students. Presence of servants was a special reason to approach students to noble culture because it was thought that the main ideal for student behavior was connected with noble traditions. It was defined that budget students had well-organized nutrition system, nevertheless, the quality of products and quantity of food weren’t at a high level. That’s why students often complain about tasteless, little nutritious food. Calculation count of calories in budget students’ food showed that they hadn’t received the right amount of calories. From time to time the university administration tried to improve students’ nutrition, but it hadn’t worked because they couldn’t raise the level of funding. At the result, in 1858 the university administration stopped to supply students with food and started to pay scholarships. After this decision, the specificity of nutrition for all students became the same. The majority of students in 1863 had problems with nutrition this shows statistics from that year. The author points out that except typical diet students had a special hospital and disciplinary cell diets. If the hospital diet was pretty much the same as the normal meal, the disciplinary cell diet included only a piece of bread and water. It is also important to emphasize that students had to follow all religious rules. That’s why they kept all fasts. During that fasting time eating meat and fats were forbidden and students’ nutrition becomes worse. At the same time, a lot of students who studied at their own expense had another system of nutrition. For example, rich students had perfect food and they visited restaurants and had their own cooks and lackeys, next to them it was easy to find a student who didn’t eat for a few days. Very often the meal was included in a price of apartment rent or students cooked by themselves. Typical price for an apartment with nutrition started from 3-4 rubles per month, in comparing lunch in ordinary Kyiv hotel cost around 10 rubles per month. Sometimes parents of students sent them food because prices in Kyiv were higher than in the region. It was also common among students to feed on in special canteen organized by Kyivan hostess. Usually, it was an old lady who served a cheap meal and sometimes students could get some food in debt. Nevertheless, a lot of students who studies at their own expanse suffered from pure nutrition. Very often bad food was the reason for bad results in studying. However, the reason for bad nutrition helped students to unite to overcome life's difficulties. It was common among students to settle together and share all food. Sometimes students organized parties where they shared all meals, this activity contributed to the merger of the student corporation.

scholarly journals THE INFLUENCE OF TECHNOLOGICAL METHODS OF CULTIVATION ON THE FORMATION OF STRUCTURAL ELEMENTS OF THE CROP OF VEGETABLE PEAS IN THE CONDITIONS OF THE RIGHT-BANK FOREST-STEPPE

2019 ◽  
pp. 21-29
Author(s):  
Ihor Didur ◽  
Voldemar Mostovenko
Keyword(s):  
Soil Nitrogen ◽  
Seed Treatment ◽  
Maximum Yield ◽  
Mineral Fertilizers ◽  
Forest Steppe ◽  
Structural Elements ◽  
Yield Level ◽  
The Right ◽  
Technological Methods ◽  
Number Of Seeds

Seed treatment with boron and molybdenum and rhizotorphine helped to increase the length of the stem. It generally provided better aeration of crops due to better light, which amounted to 87.9 cm for boron treatment and 88.5 cm for molybdenum treatment, increasing the number of seeds in beans from 7 to 8 pcs. However, the weight of 1,000 seeds decreased slightly, both for boron treatments up to 156.5 and for molybdenum treatments up to 154.3 g. In addition, the use of foliar fertilizers Nanovit Mono Bohr in the budding phase contributed to increasing the length of the stem to 91.2 cm, the number of seeds in beans to 9 pcs, the weight of 1,000 seeds to 161.4 g, and the yield level to 7.5 t / ha. In order to obtain the maximum yield of peas vegetable varieties of Skinado and Sommerwood at the level of 7-8 t / ha in the conditions of Vinnytsia it is necessary to add mineral fertilizers N40K60R60, (phosphoric and potash - under the basic cultivation of soil, nitrogen - under pre- sowing cultivation). Before planting vegetable peas, seed treatment with risotrophin, boron, molybdenum and as extra-root nutrition is carried out by Nanovite Mono Bor - 1 l / ha and Molybdenum Nanovite - 0.5 l / ha in the budding phase. Treatment of seeds with boron and molybdenum contributes to increasing the length of the stem, which in general provides better aeration of crops due to better lighting. Further study of the factors of intensification of the technology of growing vegetable peas, in particular, on the implementation of foliar infusions in the phase of seeding began to be needed.

scholarly journals Perspective resources of resistance of spring oats to loose smut

2019 ◽  
pp. 20-23
Author(s):  
L. Necheporenko ◽  
S. Vorozhko
Keyword(s):  
Sugar Beet ◽  
Geographical Origin ◽  
Plant Genetic Resources ◽  
Forest Steppe ◽  
Loose Smut ◽  
Breeding Station ◽  
Crop Area ◽  
High Yields ◽  
The Right ◽  
Very High

Goal. Search for the most valuable sources of spring oats, resistant to the defeat of loose smut. Methods. Field, finely divided. The area of the crop area is 2 m2, the repetition is three times. The study was carried out in fields at Verhnyachka experimental breeding station of the Institute of biopower crops and sugar beet of NAAS of Ukraine. The materials for the research were 94 own selection created varieties with the involvement of varieties of different ecological and geographical origin, obtained from the National Center for Plant Genetic Resources of Ukraine. Results. The results of the study of newly created spring oats varieties in the conditions of the Right Bank Forest-steppe of Ukraine in the 2015—2018 validity for resistance to the pathogen of loose smut on an artificial infectious background are given. The total share of resistant forms of the disease was established: very high — resistant — 25.5%, high- resistant — 19.1%, resistant — 17.0%, vulnerable — 21.3%, susceptible — 16.0% and 1.1% — highly susceptible. Susceptible and highly susceptible specimen were discarded, while the vulnerable specimen were involved in the process of hybridization with resistant to sustainability. Conclusions. The differentiation of varieties of spring oats for resistance to loose smut was revealed. 58 varieties of spring oats with resistance to the pathogen of 9—6 points were detected. 22 varieties are selected, which combine resistance with high yields. 5 varieties have been created: Decameron, Darunok, Dietuchnui, Dioscurii and Denka, which are in the Register of plant varieties of Ukraine, and received the “The Certificate of registration of the sample of the gene pool of plants in Ukraine” on 5 lines of oat: 467-15, 445-1791, 399-38, 477-5 and 493-27, which can be used as donors of resistance to disease.

scholarly journals THE EFFECT OF SOWING DATES AND NITROGEN FOLIAR FERTILIZATION ON SPRING BARLEY PRODUCTIVITY UNDER CONDITIONS OF RIGHT-BANK FOREST-STEPPE

2020 ◽  
pp. 51-63
Author(s):  
Mihaylo Polishchuk
Keyword(s):  
Growth And Development ◽  
Crop Yields ◽  
Spring Barley ◽  
Barley Grain ◽  
Nitrogen Fertilizers ◽  
Forest Steppe ◽  
Foliar Fertilization ◽  
Yield Level ◽  
Sowing Dates ◽  
Control Variant

In order to maximize the potential of productivity of spring barley varieties, it is important to optimize the conditions for plant growth and development, which are, first of all, provided by the latest intensive agricultural technologies, which provide for the correct placement of crops in crop rotation after the respective precursors; optimal supply of plants with nutrients, taking into account their content in the soil; fractional application of nitrogen fertilizers during the growing season by phases of growth and stages of organogenesis; the use of retardants, integrated protection of plants against weeds, pests, diseases, timely and quality implementation of all agrotechnical measures. Research to study the effectiveness of different terms of spring barley sowing and doses of nitrogen fertilizers were conducted during 2018 - 2019 in the conditions of the research field of VSAU v. Agronomichne of Vinnytsia region on gray ashed soils. Weather conditions during the years of the research differed from the average long-term data with high temperature conditions and low rainfall, and accordingly the most favorable year for the growth and development of spring barley was 2018. It is shown the 2-years investigation results on study the effect of sowing dates and nitrogen fertilizations on productivity elements and quality indexes of spring barley grain under conditions of Right-Bank Forest-Steppe on gray forest soils. Accordingly, the highest levels of harvest of barley cultivars at different sowing dates were obtained under conditions of 2018. t should also be noted that the delay of sowing by 6 days in the years of research leads to a decrease in the yield level on average for all varieties by 0,42 – 0,64 t / ha, and a delay of 14 days leads to a decrease by 1,37 – 1,80 t / ha. The use of nitrogen fertilizers leads to an increase in the yield level of both cultivated varieties, and the highest crop yields of the Svarog variety were obtained in the experiment where the background + N60 was applied in the foliar fertilization (4,87 t / ha), and the lowest respectively in the control variant 3,16 t /ha, in the Armax variety a similar situation is observed, however, with lower indicators respectively 4,54 and 3,06 t / ha. The lowest values of protein content in the grain were obtained in the control variant where only N17 P17 K17 was applied to rows when sowing, and the use of nitrogen fertilization leads to an increase in this indicator and the highest values obtained in the variant of experiment 4, where Background (N17 P17 K17) + N60 in the foliar fertilization on the feeding phase of the tube exit. Key words: spring barley, nitrogen fertilizers, elements of the crop structure, yield, quality of production.

Use of contrast in ultrasound

2011 ◽  
Author(s):  
Tomas Jansson ◽  
Anders Nilsson
Keyword(s):  
New York ◽  
Left Atrium ◽  
In Vitro Study ◽  
Rapid Injection ◽  
Doppler Signals ◽  
The World ◽  
Vitro Model ◽  
The Right ◽  
The University

In 1968, Drs Pravin M. Shah and Raymond Gramiak at the University of Rochester, New York, were conducting a study with the ultimate goal to investigate whether heart stroke volume could be estimated from the extent and duration of cusp separation of the aortic valve, as measured with M-mode ultrasound. Simultaneously, as the reference, they also measured cardiac output with the indicator dilution technique. Here, a bolus of a dye (indocyanine green) is injected and blood is sampled downstream to determine the rate at which the indicator has been transported from the injection site. In Dr Shah’s own account of the experiments, he explains that the routine at his university then was to place a catheter in the left atrium with the trans-septal technique, i.e. inserting the catheter in a vein and penetrating into the left atrium via the right atrium. During the injections of the dye, somewhat to their surprise, they observed a striking echo enhancement across the aorta. The enhancement also appeared when saline and dextrose in water was flushed through the catheter. Dr Gramiak reminded himself of a comment from Dr Claude Joyner, that a temporary echo-enhancement could be observed during saline injections, and they speculated that miniature bubbles produced by gaseous cavitation upon rapid injection of the fluid gave rise to the enhancement, and raised the idea that this could be used as a contrast agent. An in vitro study by Frederick Kremkau provided strong evidence that gas bubbles were actually responsible for the echo enhancement. It is interesting to note how discoveries are made independently around the world, when the time is ripe. At the same time in Lund, Drs Inge Edler and Kjell Lindström performed studies to measure blood flow in the heart. At this point no ultrasound Doppler signals had been recorded from the inside of the heart, and they used a calf heart in an in vitro model to verify that signals could be obtained when water and blood was led through the model.

scholarly journals High-Level Production of Porphyrins in Metabolically Engineered Escherichia coli: Systematic Extension of a Pathway Assembled from Overexpressed Genes Involved in Heme Biosynthesis

2003 ◽  
Vol 69 (8) ◽  
pp. 4875-4883 ◽  
Author(s):  
Seok Joon Kwon ◽  
Arjo L. de Boer ◽  
Ralf Petri ◽  
Claudia Schmidt-Dannert
Keyword(s):  
Escherichia Coli ◽  
High Performance ◽  
Protoporphyrin Ix ◽  
Spectroscopic Properties ◽  
Heme Biosynthesis ◽  
Promising Alternative ◽  
High Yields ◽  
High Level

ABSTRACT Due to their spectroscopic properties porphyrins are of special interest for a variety of applications, ranging from drug development or targeting to material sciences and chemical and biological sensors. Since chemical syntheses are limited in terms of regio- and stereoselective functionalization of porphyrins, a biosynthetic approach with tailored enzyme catalysts offers a promising alternative. In this paper, we describe assembly of the entire heme biosynthetic pathway in a three-plasmid system and overexpression of the corresponding genes with Escherichia coli as a host. Without further optimization, this approach yielded remarkable porphyrin production levels, up to 90 μmol/liter, which is close to industrial vitamin B12 production levels. Different combinations of the genes were used to produce all major porphyrins that occur as intermediates in heme biosynthesis. All these porphyrin intermediates were obtained in high yields. The product spectrum was analyzed and quantified by using high-performance liquid chromatography. Intriguingly, although protoporphyrin IX could be produced at high levels, overexpressed Bacillus subtilis ferrochelatase could not convert this substrate appreciably into heme. However, further investigation clearly revealed a high level of expression of the ferrochelatase and a high level of activity in vitro. These results may indicate that heme has a regulatory impact on the iron uptake of E. coli or that the ferrochelatase is inactive in vivo due to an incompatible enzyme interaction.

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