Growth abnormalities in microorganisms exposed to tobacco leaf extracts

1974 ◽  
Vol 20 (11) ◽  
pp. 1619-1621 ◽  
Author(s):  
S. A. Ghabrial

Unusual cultural changes were observed when several bacterial and yeast strains were grown on a medium containing aqueous extracts of tobacco leaves. In 24–48 h incubation on such a medium, several dark-brown papilla-like structures developed on the surface of normally smooth colonies. Moreover, smaller dark-brown refractile globular bodies were observed in the medium in areas beneath and surrounding the microbial colonies with papilla-like structures. Attempts to demonstrate the viability of these globular bodies failed. The cultural abnormalities observed on tobacco extract medium were unique to this medium since they were not detected in a wide variety of culture media tested. The lowest concentration of tobacco extract (dry wt. basis), which is required for the development of this phenomenon, was determined to be 0.5 mg/ml of medium.


2021 ◽  
Vol 271 ◽  
pp. 04031
Author(s):  
Hui Li ◽  
Yang Qu ◽  
Kaiqin Cao ◽  
Jianhan Xiong ◽  
Keying Hua ◽  
...  

The selected Moutai aromatic microorganisms and their metabolites were applied into the fermentation of tobacco leaves in order to improve the tobacco quality. The results showed that a variety of aromatic substances in Moutai, as well as the typical flavor substances commonly used in cigarettes, were detected in the fermented tobacco leaf extract. In view of the GC-MS results as well as the sensory smoking evaluation of tobacco leaf extracts under designed experimental conditions, the optimal parameters of stable single-strain fermentation process was at 40 ℃ for 10-15 days. The results of specific effects of different fermentation conditions on the content of aroma substances in different parts of tobacco leaves after fermentation, as well as the subsequent sensory evaluation, provided basic data for the improvement of tobacco fermentation and aroma flavoring technology, which was conducive to the development of new cigarettes.



1974 ◽  
Vol 185 (1080) ◽  
pp. 343-356 ◽  

Calcium phosphate co-precipitates half its mass of ribonucleic acids made from yeast, tobacco leaf and tobacco mosaic virus when the precipitate is formed in their presence. It also precipitates deoxyribonucleic acid. Degraded nucleic acids are less completely precipitated. Less nucleic acid is adsorbed by preformed calcium phosphate. In suitable circumstances nucleic acid is fixed by leaf fibre. Autolytic changes in leaf fibre, and in calcium-chelators in leaf extracts, explain many differences in the amount of nucleic acid present in extracts made from tobacco leaves in different ways.



2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yan Li ◽  
Ke Ren ◽  
Mengyang Hu ◽  
Xian He ◽  
Kaiyuan Gu ◽  
...  

Abstract Background Weather change in high-altitude areas subjects mature tobacco (Nicotiana tabacum L.) to cold stress, which damages tobacco leaf yield and quality. A brupt diurnal temperature differences (the daily temperature dropping more than 20 °C) along with rainfall in tobacco-growing areas at an altitude above 2450 m, caused cold stress to field-grown tobacco. Results After the flue-cured tobacco suffered cold stress in the field, the surface color of tobacco leaves changed and obvious large browning areas were appeared, and the curing availability was extremely poor. Further research found the quality of fresh tobacco leaves, the content of key chemical components, and the production quality were greatly reduced by cold stress. We hypothesize that cold stress in high altitude environments destroyed the antioxidant enzyme system of mature flue-cured tobacco. Therefore, the quality of fresh tobacco leaves, the content of key chemical components, and the production quality were greatly reduced by cold stress. Conclusion This study confirmed that cold stress in high-altitude tobacco areas was the main reason for the browning of tobacco leaves during the tobacco curing process. This adverse environment seriously damaged the quality of tobacco leaves, but can be mitigated by pay attention to the weather forecast and pick tobacco leaves in advance.



2021 ◽  
Vol 50 (1) ◽  
pp. 61-68
Author(s):  
Tahseen Ghous ◽  
Kalsoom Akhtar ◽  
Saiqa Andleeb ◽  
Saira Khizar ◽  
Shaukat Ali ◽  
...  

The results of antioxidant assays with Gymnema sylvestre leaf extracts revealed that methanol, acetone, and aqueous extracts possessed maximum DPPH (83, 83, and 75%) and ABTS scavenging potential (85, 71, and 82%). Chloroform possessed maximum total flavonoid (24.6 mg/100 ml) and total iron contents (435.3 ± 0.0125 mg FeSO4 E/G). The extracts of n-hexane, ethyl acetate, and chloroform of Gymnema sylvestre leaves displayed an IC50 value of 170.2, 44.4, 131.6 μg/ml, respectively in α-glucosidase inhibition assay. Methanol and aqueous extracts showed maximum inhibition of E. ammni (17 ± 2.0 and 19.6 ± 0.57 mm), E. coli (15.3 ± 0.57 and 17.6 ± 0.57 mm), and S. aureus (16.6 ± 1.52 and 19.3 ± 1.15 mm). It may be concluded that all potential effects of G. sylvestre leaf extracts were due to the presence of phytochemical constituents such as flavonoids, steroids, quinones, phenols, triterpenoids, tannins, alkaloids, and saponins. Present findings suggest that these extracts present a satisfactory source for the preparation of antioxidant and antidiabetic medicines.



2021 ◽  
Vol 65 (1) ◽  
pp. 11-22
Author(s):  
Mengyao Lu ◽  
Shuwen Jiang ◽  
Cong Wang ◽  
Dong Chen ◽  
Tian’en Chen

HighlightsA classification model for the front and back sides of tobacco leaves was developed for application in industry.A tobacco leaf grading method that combines a CNN with double-branch integration was proposed.The A-ResNet network was proposed and compared with other classic CNN networks.The grading accuracy of eight different grades was 91.30% and the testing time was 82.180 ms, showing a relatively high classification accuracy and efficiency.Abstract. Flue-cured tobacco leaf grading is a key step in the production and processing of Chinese-style cigarette raw materials, directly affecting cigarette blend and quality stability. At present, manual grading of tobacco leaves is dominant in China, resulting in unsatisfactory grading quality and consuming considerable material and financial resources. In this study, for fast, accurate, and non-destructive tobacco leaf grading, 2,791 flue-cured tobacco leaves of eight different grades in south Anhui Province, China, were chosen as the study sample, and a tobacco leaf grading method that combines convolutional neural networks and double-branch integration was proposed. First, a classification model for the front and back sides of tobacco leaves was trained by transfer learning. Second, two processing methods (equal-scaled resizing and cropping) were used to obtain global images and local patches from the front sides of tobacco leaves. A global image-based tobacco leaf grading model was then developed using the proposed A-ResNet-65 network, and a local patch-based tobacco leaf grading model was developed using the ResNet-34 network. These two networks were compared with classic deep learning networks, such as VGGNet, GoogLeNet-V3, and ResNet. Finally, the grading results of the two grading models were integrated to realize tobacco leaf grading. The tobacco leaf classification accuracy of the final model, for eight different grades, was 91.30%, and grading of a single tobacco leaf required 82.180 ms. The proposed method achieved a relatively high grading accuracy and efficiency. It provides a method for industrial implementation of the tobacco leaf grading and offers a new approach for the quality grading of other agricultural products. Keywords: Convolutional neural network, Deep learning, Image classification, Transfer learning, Tobacco leaf grading



Author(s):  
Е.И. Виневский ◽  
А.В. Чернов

Исследовано влияние параметров градиентного воздействия постоянного магнитного поля (ПМП) на интенсификацию процесса томления табачных листьев. Выдвинута рабочая гипотеза о том, что для стимулирования процесса томления листьев табака необходимо градиентное воздействие на них ПМП, возникающее в результате перемещения листьев относительно системы постоянных магнитов. Введено понятие приведенного коэффициента убыли влаги, равное отношению влажности обработанных листьев к влажности контрольных образцов – необработанных листьев. Установлено, что при использовании точечного градиентного воздействия ПМП на среднюю жилку табачных листьев частотой 0,3 Гц и продолжительности обработки в течение 115–125 с при высоте расположения магнитов 25 мм процесс томления листьев ускоряется на 28,8% в сравнении с контролем. При линейном градиентном воздействии ПМП на табачный лист с частотой 0,3 Гц процесс томления ускоряется на 4,7–15,5% в зависимости от продолжительности обработки (10–40 с). При увеличении продолжительности обработки до 80 с процесс томления листьев табака замедлился. Установлено максимальное ускорение процесса томления листьев табака: при точечном градиентном воздействии ПМП на среднюю жилку табачного листа частотой 0,3 Гц и продолжительности обработки в течение 115–125 с; при линейном градиентном воздействии ПМП на табачный лист частотой 0,3 Гц и продолжительности обработки в течение 55–65 с. The influence of the parameters of the gradient effect of a constant magnetic field (CMF) on the intensification of the process of languishing tobacco leaves is studied. A working hypothesis is put forward that to stimulate the process of tobacco languor, it is necessary to have a gradient effect on them of CMF, which occurs as a result of the movement of leaves relative to the system of permanent magnets. The concept of the reduced coefficient of moisture loss is introduced, which is equal to the ratio of the humidity of treated leaves to the humidity of control samples-untreated leaves. It was found that when using a point gradient effect of CMF on the middle vein of tobacco leaves with a frequency of 0,3 Hz and a duration of processing for 115–125 s at the height of the magnets of 25 mm, the process of leaf languor is accelerated by 28,8% in comparison with the control. When the linear gradient effect of CMF on the tobacco leaf with a frequency of 0,3 Hz, the languor process is accelerated by 4,7–15,5%, depending on the duration of treatment (10–40 s). In the future, with an increase in the processing time to 80 s, the process of languishing tobacco leaves slowed down. The maximum acceleration of the process of languishing tobacco leaves is established: for spot gradient effect of CMF on the mid-veins of tobacco leaf frequency of 0,3 Hz and duration of treatment for 115–125 s; a linear gradient in the impact of CMF on the tobacco sheet with a treatment frequency of 0,3 Hz and duration of treatment for 55–65 s.



2022 ◽  
Vol 22 (1) ◽  
Author(s):  
Florence Nalimu ◽  
Joseph Oloro ◽  
Emanuel L. Peter ◽  
Patrick Engeu Ogwang

Abstract Background Several local communities in Central, Western, Eastern, and Northern regions of Uganda have been using the whole leaf extracts of Aloe vera (L.) Burm. f. (Asphodelaceae) in the treatment of various ailments. Also, several commercial companies sell A. vera as soft drinks in Uganda. However, there are inadequate reports on the toxicities of such preparations. This paper reports the acute and sub-acute oral toxicity of aqueous extracts of whole leaf and green rind of A. vera in Wistar rats. Methods Acute oral toxicity test was carried out in female Wistar rats at doses of 175, 550, 1750, and 5000 mg/kg, p.o. The animals were observed for signs of toxicity for 14 days. Similarly, a sub-acute oral toxicity test was performed in both sexes of rats at doses of 200, 400, and 800 mg/kg, p.o. daily for 28 days. All the groups of animals were monitored for behavioral, morphological, biochemical, and physiological changes, including mortality and compared with respective controls. Body weights were measured weekly while the animals’ relative organ weights, hematological, biochemical, gross, and microscopic pathology were examined on day 29. Results There was no mortality or apparent behavioral changes at the doses tested in acute and sub-acute oral toxicity tests. Thus, the Median Lethal Dose (LD50) of green rind and whole leaf aqueous extracts was above 5000 mg/kg. Gross anatomy revealed that the rats’ relative spleen weight in green rind extract at 200 mg/kg significantly decreased compared to the control group. The creatinine levels in female rats that received green rind extract and the chloride ion levels in male rats administered whole leaf extract were significantly elevated. Conversely, Mean Corpuscular Hemoglobin Concentration (MCHC) levels significantly decreased at lower doses of the green rind extract compared to the control. Histopathology of the kidney revealed the renal interstitium’s inflammation at doses of 200 and 800 mg/kg of the whole leaf extract. Conclusion The findings demonstrated that A. vera green rind and whole leaf extracts are non-toxic at relatively high doses when used for a short duration. Prolonged use of the aqueous whole leaf extract might be associated with kidney toxicity.



AGRICA ◽  
2019 ◽  
Vol 1 (2) ◽  
pp. 1-8
Author(s):  
Maria Goreti Firma

This study aims to determine the effect of tobacco plant extracts on mortality of armyworm pests (Spodoptera litura F.) and determine the optimum concentration of tobacco leaf extracts on mortality of armyworm caterpillars on mustard plants in the field. The design used in this study was a Randomized Block Design (RBD) consisting of 5 treatments and 4 replications namely T1: 175 ml/L concentration of tobacco leaf extract, T2: 350 ml/L concentration of tobacco leaf extract T3: Concentration of 525 ml/L tobacco leaf extract, T4: Concentration of 700 ml/L tobacco leaf extract, T5: Concentration of 875 ml/L of tobacco leaf extract. The observation variables in this study were pest mortality (%), damage intensity (%), plant fresh weight, and fresh weight per hectare (ton). The results showed that the concentration of tobacco leaf extracts significantly affected the mortality of Spodoptera litura F. At the concentration of T5 treatment (875 ml) were the lowest damage, pest mortality, fresh weight of the mustard plant, and fresh weight per hectare of was 9.75%, 88%, 109.25 gr, and27.31 tons respectively.



Author(s):  
Е.Е. УЛЬЯНЧЕНКО

При производстве табачного сырья важную роль играет сокращение продолжительности сушки табачных листьев. Одним из способов интенсификации сушки свежеубранных табачных листьев является прием прорезания средней жилки (ПСЖ) листьев вдоль волокон. По результатам исследований 2019–2020 гг. была создана база данных табачного сырья, полученного при естественном способе сушки с применением приема ПСЖ, которая может служить информационным материалом для производителей табака. Проведена оптимизация процесса сушки табачного листа ПСЖ по показателям качества табачного сырья для расширенного диапазона сортотипов табака. Объектом исследований были сорта отечественной селекции, включенные в Государственный реестр селекционных достижений, допущенные к использованию: Самсун 85, Вирджиния 202, Юбилейный новый 142, Трапезонд 92, Трапезонд 204, Дюбек 33, Американ 287 и Крупнолистный Ильский (находится в стадии государственных испытаний). Критерием оценки эффективности применения приема ПСЖ на исследованных сортах табака являлся совокупный сравнительный анализ следующих показателей контрольных (без ПСЖ листа) и опытных образцов: уровень интенсификации сушки, показатели товарного качества, технологических свойств и химического состава полученного сырья. Установлено, что ПСЖ позволяет интенсифицировать процесс сушки в 1,3–2,46 раза в зависимости от сорта табака и положительно влияет на технологические свойства сырья, у большинства сортов увеличивается выход волокна и сохраняются объемно-упругие свойства. Динамика сушки оказывает влияние на изменение химического состава сырья. В процессе сушки за счет гидролизации солей никотина и его освобождения путем окисления кислородом воздуха уровень никотина в ряде образцов снижается в пределах 10–30%. Чем выше содержание никотина, тем выше крепость табака, грубее его вкус. Изменения углеводно-белкового соотношения в сторону повышения углеводов улучшают вкусовые характеристики сырья. По каждому исследованному сорту не удалось выявить закономерной зависимости его структуры и характера процесса сушки при ПСЖ с преобразованиями химического состава сырья. На основе анализа технологических и качественных показателей табачного сырья, представленных в разработанной базе данных по интенсификации сушки различных сортов табака с применением приема ПСЖ табачных листьев, можно планировать выбор оптимального способа сушки для каждого сорта табака, позволяющего повысить эффективность использования сырья и улучшить его качественные характеристики. In the production of tobacco raw materials, reducing the drying time of tobacco leaves plays an important role. One of the ways to intensify the drying of freshly harvested tobacco leaves is the method of cutting the middle vein (CMV) of the leaves along the fibers. Based on the results of research in 2019–2020, a database of tobacco raw materials obtained by a natural drying method using CMV reception was created, which can serve as information material for tobacco producers. The optimization of the process of drying the CMV tobacco leaf according to the quality indicators of tobacco raw materials for an expanded range of tobacco variety types was carried out. The object of research was the varieties of domestic selection included in the State Register of Breeding Achievements, approved for use: Samsun 85, Virginia 202, Yubileyny novy 142, Trapezond 92, Trapezond 204, Dubek 33, American 287 and Krupnolistnyy Ilskiy (under state testing). The criterion for evaluating the effectiveness of the use of CMV intake on the studied tobacco varieties was a cumulative comparative analysis of the following indicators of control (without CMV sheet) and experimental samples: the level of drying intensification, indicators of commercial quality, technological properties and chemical composition of the obtained raw materials. It is established that CMV allows to intensify the drying process by 1,3–2,46 times, depending on the tobacco variety and has a positive effect on the technological properties of raw materials, most varieties increase the yield of fiber and retain volume-elastic properties. The dynamics of drying affects the change in the chemical composition of raw materials. During the drying process, due to the hydrolysis of nicotine salts and its release by oxidation with air oxygen, the nicotine level in a number of samples decreases within 10–30%. The higher the nicotine content, the higher the strength of tobacco, it is coarser in taste. Changes in the carbohydrate-protein ratio in the direction of increasing carbohydrates improve the taste characteristics of raw materials. For each studied variety, it was not possible to identify a regular dependence of its structure and the nature of the drying process at CMV with transformations of the chemical composition of raw materials. Based on the analysis of technological and qualitative indicators of tobacco raw materials presented in the developed database on the intensification of drying of various varieties of tobacco using the use of CMV of tobacco leaves, it is possible to plan the choice of the optimal drying method for each variety of tobacco, which allows to increase the efficiency of using raw materials and improve its quality characteristics.



Weed Science ◽  
1989 ◽  
Vol 37 (5) ◽  
pp. 665-669 ◽  
Author(s):  
Albert E. Smith

Research was conducted to determine the potential for allelopathy to occur in pastures infested with bitter sneezeweed. Aqueous extracts of bitter sneezeweed leaves reduced alfalfa and Italian ryegrass seedling growth as much as 50% at concentrations of 0.5% (w/v). Leaf extracts were more phytotoxic than either stem or root extracts and seedling growth was reduced more than seed germination. Bitter sneezeweed tissue mixed in potting soil at concentrations as low as 0.3% w/w reduced alfalfa seedling numbers by 43%, plant height by 26%, and foliage dry matter production by 54% compared to plants cultured in soil without bitter sneezeweed leaf tissue. The potential concentration of bitter sneezeweed leaf material in soil in the pasture ecosystem was determined to be 0.5% w/v in the liquid phase and 0.2% w/w in the solid phase. Alfalfa seedling growth was reduced by 70% when germinating seed were placed under a bell jar with a potted mature bitter sneezeweed plant compared to control seedlings. A potential exists for bitter sneezeweed interference with developing alfalfa and Italian ryegrass seedlings following fall interseeding into pastures infested with bitter sneezeweed.



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