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1.
The inhibitory effect of mimosine on polyphenoloxidase (PPO) from the cephalothorax of Pacific white shrimp (Litopenaeus vannamei) was studied. Mimosine showed inhibitory activity toward PPO from white shrimp with an apparent molecular weight of 210 kDa as evidenced by the decrease in the activity staining band, as compared to the control. An inhibition kinetic study revealed that mimosine exhibited the mixed type reversible inhibition on PPO from white shrimp with a Ki value of 3.7 mM. Mimosine showed copper (Cu2+) reduction and chelating capacity in a dose dependent manner. Mimosine could react with the intermediate browning product, thereby rendering lower red-brown color formation. Therefore, mimosine could inhibit PPO by different modes of inhibition and could be used to prevent melanosis formation in Pacific white shrimp.  相似文献   
2.
Medicinal plants are in huge demand since the consumption is widespread and ever-increasing globally. The conventional breeding programs are generally environmental dependent; prone to different biotic and abiotic stresses as well as the secondary metabolite content is too low to harvest. In this context, developing polyploid individuals artificially would be a remarkable approach to increase vigor and attain this objective. Polyploids often exhibit some morphological features that are different or greater in forms than their diploid progenies. Polyploidization can be induced by quite a few antimitotic agents. The most frequently used antimitotic chemicals are colchicine, trifluralin, and oryzalin. The whole method of induced chromosome doubling consists of a series of steps, including an induction phase, regrowth phase, and a confirmation technique to evaluate the rate of achievement. The induction phase depends on different factors, such as explant types, antimitotic agents, its different concentrations, and exposure durations. To evaluate the accomplishment of polyploidization, morphological or anatomical observations are recorded as a rapid method. However, chromosome count and flow cytometry are the most eminent method for absolute confirmation. Despite significant prospects of polyploidization, there has been very little research on medicinal plants. The current review gives an overview of the different parameters of in vitro chromosome doubling, the history of the technique, and progress made over the last two decades.  相似文献   
3.
Ganjare AB  Nirmal SA  Patil AN 《Fitoterapia》2011,82(7):1052-1056
Cordia dichotoma f. (Boraginaceae) is a small deciduous tree from India. The bark of was used in the treatment of ulcerative colitis (UC) and colic pain traditionally hence present work was undertaken to identify the phytoconstituent responsible for this activity. Apigenin is isolated by column chromatography from methanol fraction of crude methanol extract of C. dichotoma bark. Structure of apigenin is established by various spectroscopic studies. Apigenin (5 mg/kg, p.o.) showed significant healing and reduction in inflammatory enzymes when screened for UC. It can be concluded that apigenin from C. dichotoma bark may be responsible for the treatment of UC.  相似文献   
4.
Summary The haematological values of haemoglobin (Hb), packed cell volume (PCV) and vitamin levels of folacin (folic acid), cyanocobalamin (vitamin B12) of buffaloes, in a surra endemic area of Eastern Haryana, India, were determined. Surra-positive buffaloes had significantly low levels of Hb, PCV, folic acid and vitamin B12. These low levels of folic acid and vitamin B12 may have enhanced the clinical signs of chronic trypanosomosis, caused byTrypanosoma evansi.
Folacina Y Cianocobalamina En Relacion Con La Infeccion Natural De Bufalos ConTrypanosoma Evansi
Resumen Se determinaron los valores hematológicos de hemoglobina (Hb), volumen corpuscular celular (PCV) y los niveles vitamínicos de ácido fólico y cianocobalamina (vitamina B12) de búfalos, en un área endémica de surra en Haryana Oriental, India. Los búfalos positivos a surra tuvieron niveles bajos de Hb, PCV, ácido fólico y vitamina B12. Los niveles bajos de ácido fólico y cianocobalamina, pudieron haber exacerbado los sintomas clinicos de tripanosomiasis crónica, causada porTrypanosoma evansi.

Folacine Et Cyanocobalamine En Relation Avec La Trypanosomose ATrypanosoma Evansi Chez Des Buffles
Résumé Les valeurs hématologiques de l'hémoglobine (Hb), l'hématocrite (PCV) et les taux de la folacine (acide folique) et de la cyanocobalamine (vitamine B12) chez des buffles ont été déterminés dans une région de l'Est Haryana, Inde, où sévit le surra à l'état endémique. Les buffles positifs vis-à-vis du surra présentaient des taux significativement faibles de Hb, PCV, d'acide folique et de vitamine B12. Les taux peu élevés de ces deux derniers éléments peuvent renforcer les siqnes cliniques de la trypanosomose chronique, due àT. evansi.
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5.
We previously reported that the majority of in vitro monocyte/macrophage activation exhibited by extracts of Echinacea and other botanicals depends upon bacterial lipopolysaccharides and Braun-type bacterial lipoproteins. We determined the contribution made by these bacterial components to the overall immune-enhancing activity detected in E. purpurea and E. angustifolia bulk root and aerial material obtained from six major growers/suppliers in North America. Substantial variation in activity (up to 200-fold) was observed in extracts of these materials when tested in two monocyte/macrophage cell lines. The majority of activity was negated by treatment with agents that target bacterial lipoproteins (lipoprotein lipase) and lipopolysaccharides (polymyxin B). Experiments comparing the activity of freeze-dried, freshly harvested Echinacea plants to those harvested and dried using various commercially relevant conditions suggest that postharvesting procedures do not substantially contribute to the variation observed in the commercial material.  相似文献   
6.
Vanilla is naturally distributed in Mexico and parts of Central America and the history of origin of cultivated vanilla suggests that the entire stock outside Mexico may be from a single genetic source. In the present study, RAPD polymorphism was used to estimate the level of genetic diversity and interrelationships among different collections of Vanilla planifolia Andr., and few related species, including both leafy and leafless types such as V. tahitensis J.W.Moore, V. andamanica, Rolfe, V. pilifera Holtt., and V. aphylla Blume. Studies revealed that there are very limited variation within collections of V. planifolia, indicative of its narrow genetic base, and of the related species we tested, V. tahitensis is nearest to V. planifolia. The species studied are diverse and have a similarity ranging from 1.2 to 57.3 %. Of the sampled taxa, V. andamanica is the most divergent and there is also reasonable variability within its collections, indicating the possibility of natural seed set. A total of 82 polymorphic bands expressed in the RAPD profiles were used to generate a genetic distance matrix, which was then used in cluster analysis. Specific groupings were revealed by the cluster analysis whereby the leafless forms (V. aphylla, V. pilifera and the new species) and V. andamanica formed separate clusters. This is the first report of species interrelationship studies, including both cultivated and wild vanilla species.  相似文献   
7.
Modern agricultural practices have posed a detrimental impact on the environment due to their intensive use to meet the food demands of an ever-increasing population. In this context, microalgal bioinoculants, specifically cyanobacteria and green microalgae, have emerged as sustainable options for agricultural practices to improve soil organic carbon, nutrient availability, microbial quality, and plant productivity. An overview of current and future perspectives on the use of microalgal bioinoculants in agriculture practices is presented in this review, along with a discussion of their interactions with soil biotic and abiotic factors that affect soil fertility, plant health, and crop productivity. The benefits of microalgal bioinoculants include releasing agronomically important metabolites (exopolymers and phytohormones) as well as solubilizing soil nutrients. Furthermore, they function as biocontrol agents against soil-borne pathogens and facilitate the establishment of rhizosphere communities of agricultural importance. So far, very few studies have explored the basic mechanisms by which microalgal bioinoculants interact with soil biotic and abiotic factors. In recent years, advanced molecular techniques have contributed to a better understanding of these interactions.  相似文献   
8.
9.
Investigation of expression pattern of molecular markers in oral epithelial tissues would help to assess the cell differentiation and proliferation as well as early diagnosis of precancerous and cancerous lesions of the oral cavity. Aim of the present study was to investigate the protective effect of berberine on expression pattern of apoptotic, cell proliferative, inflammatory and angiogenic markers during 7,12-dimethylbenz(a)anthracene (DMBA) induced hamster buccal pouch carcinogenesis. Immunohistochemical staining [p53, Bcl-2, Bax, Proliferating Cell Nuclear Antigen (PCNA) and Vascular Endothelial Growth Factor (VEGF)], Enzyme Linked Immuno Sorbent Assay (ELISA) [c-fos, COX-2, caspase-3 and -9] and Real-Time PCR [Cyclin D1 and NFkappaB] were utilized to assess the expression pattern of molecular markers in DMBA induced hamster buccal pouch carcinogenesis. Over expression of mutant p53, PCNA, Bcl-2 and VEGF were noticed in hamsters treated with DMBA alone. Decreased expression of Bax protein was noticed in hamsters treated with DMBA alone. Increased expression of C-fos, COX-2, NFkappaB and Cyclin D1 and decreased activities of caspase-3 and -9 were also noticed in hamsters treated with DMBA alone. Oral administration ofberberine at a dose of 75 mg kg(-1) b.w. brought back the expression of above mentioned molecular markers to near normal pattern in hamsters treated with DMBA. The present results thus suggest that berberine has potent anti-inflammatory, anti-angiogenic, anti-cell proliferative and apoptosis inducing properties in DMBA induced oral carcinogenesis.  相似文献   
10.
Individual-tree distance independent diameter growth models were developed for black spruce and jack pine plantations. Data used in this study came via stem analysis on 1170 black spruce (Picea mariana [Mill.] B.S.P.) and 800 jack pine (Pinus banksiana Lamb.) trees sampled from 75 stands of 25 even-aged monospecific plantations for each species in the Canadian boreal forest region of northern Ontario. Of the 75 stands, 50 were randomly selected for each species and all trees from these stands were used for model development. Trees from the remaining stands were used for model evaluation.A nonlinear mixed-effects approach was applied in fitting the diameter growth models. The predictive accuracy of the models was improved by including random effects coefficients. Four selection criteria - random, dominant or codominant, tree size close to quadratic mean diameter, and small sized - were evaluated for accuracy in predicting random effects for a new stand using the developed models. Random effects predicted based on trees selected using the random selection criterion provided more accurate diameter predictions than those using trees obtained via other selection criteria for both species. The models developed here are very important to forest managers as the diameters predicted by these models or, their stand-level summaries (i.e., basal area, average diameter), are used as inputs in any forest growth and yield models. In addition, individual-tree diameter growth models can be used to directly forecast changes in diameter distribution of stands.  相似文献   
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