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51.
Precedence of microbial colorants can be seen in almost all the industrial sectors viz. food, textile, paper, agriculture, pharmaceutical, and cosmetics. These colorants are gaining popularity due to their salient advantages over synthetic and natural dyes. This study deals with the optimization and extraction of such colorants from Penicillium minioluteum for the purpose of dyeing different protein fibers. Penicillium minioluteum was cultured under different growth conditions to optimize the extracellular color production. The extracellular colorant grown under optimized fermentation conditions (medium-sabouraud; pH-5.6; temperature-15 °C; time-20 days; incubation-static) in 3000 ml haffkine flask showed maximum color or highest optical density of 1.014 at λ max=490 nm. Later on, this colorant was extracted using nbutanol. The remaining mycelial mat obtained after filtration was extracted using different chemical and mechanical procedures to get the intracellular colorant. Highest O.D of 0.897 was recorded at λ max=490 nm when desiccated powdered mycelial mat was extracted with methanol. Dyed silk and leather with the extracellular colorant showed color strength (K/S) as 3.88 and 3.81, respectively, whereas silk and leather dyed with the intracellular colorant showed K/S as 0.56 and 0.55, respectively. The color strength of extracellular dyed samples was found to be three times higher as compared to the samples dyed with the intracellular aqueous colorant of the same optical density. After dyeing, two different shades were obtained viz. deep red with the extracellular colorant and beige with the intracellular colorant on mulberry silk and wet blue goat nappa skin leather. Fastness towards rubbing was found to be good for both the samples. Wash fastness was excellent on silk. Fastness towards light was poor for both silk and leather. Furthermore, the color yield of the extracellular colorant (0.62 %) was found to be approximately five times more than the color yield of the intracellular colorant (0.14 %).  相似文献   
52.
A bio-inoculation experiment was performed on Ruta graveolens L., known as “Garden Rue” seedlings for the biomass production. Seedlings were inoculated with single and in combined mycorrhizal treatments. All inoculated seedlings showed significant biomass production than control seedlings. The phosphorus (P) content was more in seedlings inoculated with consortium of three native VAM fungi followed by Glomus mosseae, Acaulospora laevis and Gigaspora gigantea alone treatments. The control seedlings had the least P content but root P content was more than shoot P content in all treatments. The biomass of shoot and root was also significantly more in seedlings inoculated with consortium followed by G. mosseae, A. laevis and G. gigantea alone treatment. The control seedlings again had low shoot and root biomass. The Biovolume index (Bi) was also high in all inoculated treatments than non-inoculated control but consortium treatment (7.98) had at par Bi than rest of inoculation treatments. The quality index (Qi) value was also high in mixed consortium (1.42) and A. laevis treatment (1.42) each respectively than G. mosseae (1.38) and G. gigantea (1.29) treatments. Control seedlings had low value of Qi (1.27). The present study indicates that G. mosseae, A. laevis, G. gigantea are the best strains of VAM symbionts when mixed together for inoculating the R. graveolens to get higher yield of biomass. A. laevis is also good strain of VAM fungi for the same purpose. The G. gigantea alone proved least effective strain for inoculation purpose in R. graveolens but when mixed together in consortium of native VAM fungi as described above executed good results for enhancing the biomass production.  相似文献   
53.
Analysis of husked barleys for proanthocyanidins and malt qualityattributes has shown that not a single variety is free ofproanthocyanidins. The proanthocyanidins in barley grains variedfrom 3.85 to 4.94 mg/g as catechin equivalent. The concentrationof proanthocyanidins decreased, while total soluble sugars, reducingsugars, diastatic power and -amylase activity increasedduring maltings as well as with exogenous gibberellic acid (GA3)application. Alfa 93 (two-row) and RD2560 (six-row) varietiesappeared to be superior for malting and brewing purposes on thebasis of proanthocyanidins, total phenols, diastatic power and-amylase activity. It is suggested that exogenous applicationof GA3 at 15 ppm may be useful for producing good quality maltfrom barley grains.  相似文献   
54.
BACKGROUND: Serotonin is believed as an important factor in brain function. The role of serotonin in cerebral psycho-patho-physiology has already been well established. However, the function of serotonin antagonist in anesthetized subjects under hyperthermia has not been studied properly. METHODS: Experiments were performed in three groups of urethane-anesthetized rats, such as: (i) control group, (ii) whole body hyperthermia group and (iii) p-CPA (para-Chlorophenylalanine) pretreated hyperthermia group. Hyperthermia was produced by subjecting the rats to high ambient temperature of 38 +/- 1 degrees C (relative humidity 45-50%). Each group was divided for EEG (electroencephalogram) study and for determination of edematous swelling in the brain. RESULTS: Urethane anesthetized rats under hyperthermia show highly significant reduction in their survival time. The body temperature recorded during the hyperthermia was observed with significant and linear rise with marked increase in brain water content, which was analyzed just after the death of the subjects. The results of the electroencephalographic study in urethane-anesthetized rats recorded before death indicate that brain function varies in systematic manner during hyperthermia as sequential changes in EEG patterns were observed. However, a serotonin antagonist, p-CPA pretreatment increases the survival time with significant reduction in edematous swelling in brain but it does not affect the relationship between the core body temperature and the brain cortical potentials as observed in urethane anesthetized subjects exposed to whole body hyperthermia. The core body temperature in p-CPA pretreated rats show non-linear relationship with respect to the exposure time as it was observed in drug untreated subjects. CONCLUSION: The findings of the present study indicate that although pretreatment of p-CPA in rats has a marked correlation between the extravasations of the blood-brain barrier under hyperthermia but shows minimum effect on the EEG in a model of hyperthermia under irreversible anesthesia.  相似文献   
55.
Whole-genome sequencing of the protozoan pathogen Trypanosoma cruzi revealed that the diploid genome contains a predicted 22,570 proteins encoded by genes, of which 12,570 represent allelic pairs. Over 50% of the genome consists of repeated sequences, such as retrotransposons and genes for large families of surface molecules, which include trans-sialidases, mucins, gp63s, and a large novel family (>1300 copies) of mucin-associated surface protein (MASP) genes. Analyses of the T. cruzi, T. brucei, and Leishmania major (Tritryp) genomes imply differences from other eukaryotes in DNA repair and initiation of replication and reflect their unusual mitochondrial DNA. Although the Tritryp lack several classes of signaling molecules, their kinomes contain a large and diverse set of protein kinases and phosphatases; their size and diversity imply previously unknown interactions and regulatory processes, which may be targets for intervention.  相似文献   
56.
Common beans (Phaseolus vulgaris) are separated into two distinct groups: Andean and Middle American. We identified CAL 143 as the first Andean bean with resistance to angular leaf spot disease caused by Phaeoisariopsis griseola. Angular leaf spot is the most widespread and economically important bean disease in southern and eastern Africa, and it is especially severe on the extensively grown Andean beans. Cal 143 was resistant in Malawi, South Africa, Tanzania, and Zambia, but it was susceptible in Uganda. This was attributed to the presence of races of P. griseola in Uganda not present in the other countries. We identified two additional Andean bean lines, AND 277 and AND 279, with resistance to angular leaf spot in Malawi. We also characterized the virulence diversity of 15 isolates of P. griseola from southern and eastern Africa into nine different races. Five of six isolates from Malawi and two of seven from Uganda, obtained from large-seeded Andean beans, were characterized into four different races considered Andean. These were compatible only or mostly with large-seeded Andean cultivars. The other eight isolates from Uganda, Malawi, and the Democratic Republic of Congo, obtained from a small- or medium-seeded Middle American beans, were characterized into five different Middle American races. These were compatible with Middle American and Andean cultivars. CAL 143 was resistant or intermediate under greenhouse conditions to all but one of the same 15 isolates from southern and eastern Africa, but it was susceptible to an isolate from Uganda obtained from a medium-seeded Middle American bean. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
57.
Paddy and Water Environment - The present study utilizes soil water balance and HYDRUS-1D for estimating and predicting potential recharge in groundwater declining region of central Punjab,...  相似文献   
58.
Summary This paper reports adaptations of a generic crop model IN FOCROP for potato and its application in increasing the efficiency of agronomic experiments in tropical environments. A dataset of 13 experiments consisting of 153 treatments was assembled from an extensive literature search. These experiments were conducted over the period 1976-1999 in diverse Indian locations from 31 °N 75 ° E to 25 ° N 85 ° E. The treatments varied in locations, seasons, planting dates, water and N management and varieties. The duration to tuber initiation in the dataset varied between 25–63 days after planting and tuber yield between 11.0-45.3 t ha-1. Simulated trends of phenological development, growth and tuber yield were in close agreement with the measured with acceptable error. It was concluded that the model was adequate to simulate the effect of various crop management factors to obtain quick results and increase the efficiency of agronomic experiments.  相似文献   
59.
The contact and feeding toxicity of NeemAzal T/S (EID Parry, Chennai, India) to the parasitoid Encarsia sophia (Girault & Dodd) was compared with three synthetic insecticides (chlorpyriphos, endosulfan and triazophos) against immatures and adult emergence. NeemAzal T/S (1.0%) at lower dose (200 mg/l) did not cause any effect on the emergence of E. sophia adults, but there was a significant reduction in emergence at higher doses (800 mg/l). Also, it did not show contact toxicity to adults of E. sophia, but there was a significantly high feeding mortality in a dosage dependant manner, whereas chlorpyriphos, endosulfan and triazophos showed high toxicity both by contact and feeding method. Three neem preparations registered in India, NeemAzal T/S, Nimbecidine (T. Stains, Coimbatore) and Godrej Achook (Godrej Agrovet, Mumbai) were tested against egg and larval stages of Chrysoperla carnea (Stephens) at three dosages, using a synthetic insecticide, triazophos 40 EC (200 mg/l), for comparison under laboratory conditions. The three biorationals did not induce any adverse effect on the hatchability of C. carnea eggs. The mortality of the first instars of C. carnea was not affected by any of the azadirachtin enriched formulations; however, at higher dosage of 800 mg/l these neem based products resulted in increased mortality of the first and second instar larvae of C. carnea relative to the untreated controls. Whereas, triazophos induced very high mortality rates (85.0, 89.0 and 81.5%) of all the three larval instars. The neem based insecticides showed a dosage-dependant effect on the larval instars of C. carnea. Thus, these biorationals show that there is a potential to use them in an IPM system, being safe for natural enemies of B. tabaci in cotton.  相似文献   
60.
Coarse-textured soils are puddled to reduce high percolation losses of irrigation water under rice (Oryza sativa L.). This practice, however, reduces yield of succeeding wheat (Triticum aestivum L.) owing to deterioration in soil physical conditions. The 6 year field study reported in this paper evaluated the effects of puddling level and integrated N management on the development of subsurface compaction and growth and yield of rice and the following spring wheat grown in 1 year sequence on a sandy loam soil. Treatments were combinations of three puddling levels: low (one discing and one planking), medium (two discings and one planking), and high (four discings and one planking), and three nitrogen sources: (1) 120 kg N ha−1 from urea, (2) 60 kg N ha−1 from urea plus sesbania (Sesbania aculeata Pers.) green manure, and (3) 60 kg N ha−1 from urea plus 20 Mg ha−1 farmyard manure. Percolation rate decreased from 14 mm day−1 with low puddling to 10 mm day−1 with high puddling, with a corresponding reduction in irrigation water requirement of rice of about 20%. Bulk density profiles in the 0–30 cm soil layer showed the formation of a compact layer at 15–20 cm depth, and bulk density increased with puddling level and cropping season. The impact of organic amendments in reducing bulk density was immediate, but the rate of increase in bulk density with time was the same in all the nitrogen sources. Organic amendments did not affect percolation rate and irrigation requirement of rice. Rice yields were not significantly affected by puddling and N source treatments throughout the study period. Residual effects of treatments on wheat yield were observed from the second season onwards. Interactive effects of puddling and N source on yields of rice and succeeding wheat were not significant. Yield differences in wheat between high and low puddling were 8% and 11% during the second and the fifth cropping season, respectively. This study indicates that medium puddling was optimum, as it reduced percolation without decreasing yield of succeeding wheat.  相似文献   
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