Effect of Temperature, NaCl and Ferulic Acid Concentration on Bioconversion of Ferulic Acid to 4-Vinylguaiacol and 4-Ethylguaiacol by Halotolerant Yeasts Candida versatilis

2017 ◽  
pp. 289-297 ◽  
Author(s):  
Wei Qi ◽  
Wen-Tao Zhang ◽  
Fu-Ping Lu
Keyword(s):  
Ferulic Acid ◽  
Acid Concentration ◽  
Effect Of Temperature ◽  
Candida Versatilis

Observations on the Anodic Behavior off Nickel and Chromium: Surface Topography and Temperature Effect

CORROSION ◽  
1966 ◽  
Vol 22 (2) ◽  
pp. 32-38 ◽  
Author(s):  
J. R. MYERS ◽  
W. B. CROW ◽  
F. H. BECK ◽  
R. K. SAXER
Keyword(s):  
Activation Energy ◽  
Surface Topography ◽  
Passive Film ◽  
Acid Concentration ◽  
Passive State ◽  
Effect Of Temperature ◽  
Nickel Surface ◽  
Passive Region ◽  
Potential Region ◽  
Metallographic Examination

Abstract Metallographic examination of anodically polarized nickel and chromium after long-time exposure at selected active, passive and transpassive potentials in H2-saturated, IN H2SO4 at 25 C (77 F) revealed significant differences in surface topography. Etch figures, present only in the trans-passive state, supported the belief that “active patches” are generated in passive films of these metals at potentials more noble than the passive region. The difference in nature of nickel surface in the early trans-passive region and visible oxygen evolution region is discussed. Effect of temperature on passive nickel (i.e., nickel in passive potential region) over the range 25 to 95 C (77 to 203 F) was determined for H2-saturated 0.5, 1, 5 and ION H2SO4 (pH = 0.85 to −1.05). Apparent activation energies for dissolution of passive nickel were determined. Inflection temperature (Ti) above which “active patches” apparently are formed in passive film was dependent on acid concentration according to the expression 1/Ti × 103 = −0.11 pH+ 3.04 over the pH range investigated and was independent of the direction from which the temperature was approached. The change in apparent activation energy (ΔQ) was a function of direction from which the temperature was approached. Measurements in which temperature was increased stepwise showed that ΔQ is related to pH by the expression ΔQ (kg - cal/mole) = 15,4 pH - 4.7 for acid concentrations studied. Because Ti and ΔQ are dependent on acid concentration, Seeger's activation energy for crystallization of a very thin pseudomorphic film and Kramer's exo-electron emission temperature which are independent of concentration cannot be used to explain fully generation of “active patches” in a passive film as proposed by previous investigators.

scholarly journals Mechanism of Excessive Nitrogen Fertilization Aggravates the Damage of Cacopsylla Chinensis to Pear

2021 ◽  
Author(s):  
Zifang Qin ◽  
Yang Ge ◽  
Wantong Jia ◽  
Liu Zhang ◽  
Mingyue Feng ◽  
...  
Keyword(s):  
Amino Acid ◽  
Ferulic Acid ◽  
Acid Concentration ◽  
Nitrogen Fertilization ◽  
Molecular Mechanisms ◽  
Amino Acid Content ◽  
Nitrogen Fertilizers ◽  
High Nitrogen ◽  
Amino Acid Synthesis ◽  
Pear Trees

Abstract Cacopsylla chinensis (Hemiptera: Psyllidae) is one of the most important pests on pear trees. Although nitrogen fertilization is known to often benefit the performance of many herbivores including psyllids, physiochemical and molecular mechanisms of how psyllids respond to excessive nitrogen application remain unclear. Study showed that nitrogen fertilizer concentrations significantly impacted phenolic acids compositions in pear leaves, there was an upward trend in ferulic acid concentration when increasing nitrogen fertilizers. The increased ferulic acid concentration accelerated the C. chinensis development. Moreover, high nitrogen fertilization also caused a significant increase in psyllid honeydew secretion and several amino acids concentrations in honeydew. The increased amino-acid content in pear leaves under high nitrogen fertilization improved the feed intakes of psyllid, however decreased more significantly the expression levels of several C. chinensis genes in amino-acid synthesis pathways. The mechanism of excessive nitrogen fertilization aggravating the damage of C. chinensis to pear trees was defined preliminarily.

scholarly journals A study on the effect of parameters on lactic acid production from whey

2016 ◽  
Vol 18 (1) ◽  
pp. 58-63 ◽  
Author(s):  
Hamidreza Ghafouri Taleghani ◽  
Ghasem D. Najafpour ◽  
Ali Asghar Ghoreyshi
Keyword(s):  
Lactic Acid ◽  
Acid Concentration ◽  
Acid Production ◽  
Lactic Acid Production ◽  
Dry Weight ◽  
Optimal Growth ◽  
Inoculum Size ◽  
Effect Of Temperature ◽  
Lactic Acid Concentration ◽  
Initial Substrate

Abstract In batch fermentation of whey, selection of suitable species at desired conditions such as substrate, product concentrations, temperature and inoculum size were investigated. Four Lactobacillus species and one Lactococcus species were screened for lactic acid production. Among them L. bulgaricus ATCC 11842 were selected for further studies. The optimal growth of the selected organism for variable size of inocula was examined. The results indicated that inoculum size had insignificant effect on the cell and lactic acid concentration. The effect of temperature was also studied at 32, 37, 42 and 47°C. Results showed that the concentration of cell dry weight increased with increment of temperature from 32 to 42°C. The maximum cell and lactic acid concentration was obtained at 42°C. The effect of initial substrate concentration on lactic acid production was also examined. The optimum initial lactose concentration was found to be 90 g/l.

scholarly journals Effect of temperature and acid concentration on lanthanum extraction from spent catalyst using organic acid

2019 ◽  
Vol 478 ◽  
pp. 012017
Author(s):  
H T B M Petrus ◽  
A Wijaya ◽  
A D P Putra ◽  
Y Iskandar ◽  
D Bratakusuma ◽  
...  
Keyword(s):  
Organic Acid ◽  
Acid Concentration ◽  
Effect Of Temperature ◽  
Spent Catalyst

Variation in Ferulic Acid Concentration among Diverse Barley Cultivars Measured by HPLC and Microspectrophotometry

1998 ◽  
Vol 46 (4) ◽  
pp. 1350-1354 ◽  
Author(s):  
J. M. Zupfer ◽  
K. E. Churchill ◽  
D. C. Rasmusson ◽  
R. G. Fulcher
Keyword(s):  
Ferulic Acid ◽  
Acid Concentration ◽  
Barley Cultivars

scholarly journals THE EFFECT OF TEMPERATURE AND NITRATE COMPOUND ON GROWTH, BIOMASS AND FREE FATTY ACID CONTENT ON MICROALGAE CULTURE OF Spirulina sp. and Skeletonema sp.

2018 ◽  
Vol 7 (1) ◽  
pp. 01-11
Author(s):  
Nita Rukminasari ◽  
Muhammad Lukman ◽  
Rahmadi Tambaru ◽  
Dwi Fajriyati Inaku ◽  
Suharto Suharto
Keyword(s):  
Growth Rate ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Acid Concentration ◽  
Fatty Acid Content ◽  
Lipid Production ◽  
Fatty Acid Concentration ◽  
Effect Of Temperature ◽  
Free Fatty Acid Concentration ◽  
Increasing Temperature

Temperature and availability nutrients played an important role on growth and lipid production of microalgae. In this study, we examined the effect of increasing suhu and excessed and depleted NO3 on growth rate, biomass and free fatty acid concentration in the Spirulina sp and Skeletonema sp. Two microalgae were culture on Conway and Milne media for 21 days using continuous culture technique. There were four temperature treatments, such as 28oC, 30oC, 32oC and 34oC and three nutrient treatments, which were control nutrient treatment, without NO3 and two times NO3 concentrations from control treatments with three replicates for each treatments. Results found that increasing temperature significantly affected on biomass and concentration free fatty acid, meanwhile nutrient treatments affected on growth rate, biomass and concentration of organic Carbon. In general, increasing temperature was more affected on Spirulina sp in terms of increasing growth rate, biomass and free fatty acid concentration. However, Skeletonema sp was more responsive to availability of NO3 in the media culture for increasing free fatty acid, and percentage of free fatty acid per dry weight.

scholarly journals Xylose production from sugarcane bagasse by surface response methodology

2009 ◽  
Vol 13 (1) ◽  
pp. 75-80 ◽  
Author(s):  
José E. de Paiva ◽  
Iriani R. Maldonade ◽  
Adilma R. P. Scamparini
Keyword(s):  
Sulphuric Acid ◽  
Acid Concentration ◽  
Sugarcane Bagasse ◽  
Effect Of Temperature ◽  
Central Composite Rotatable Design ◽  
Surface Response Methodology ◽  
Hydrolysis Process ◽  
Xylose Production ◽  
Central Composite ◽  
Sulphuric Acid Concentration

The aim of this study was to optimize the production of xylose from sugarcane bagasse. The hydrolysis process was carried out to evaluate the effect of temperature and sulphuric acid concentration on the xylose production at 18, 30, and 50 min of hydrolysis. A Central Composite Rotatable Design (CCRD) was used to study two process variables, temperature (111.5; 114.0; 120.0; 126.0 and 128.5 ºC) and sulphuric acid concentration (0.20; 0.70; 1.90; 3.10 and 3.60% v v-1). Sulphuric acid had a greater influence on the hydrolysis process than temperature. At concentrations of sulphuric acid higher than 3.10% (v v-1), raising temperature had little influence on the yield of xylose production. The best condition to obtain xylose (266.73 mg g-1 of dry bagasse) was at 18 min of reaction, at 126 ºC and 3.10% (v v-1) of sulphuric acid, representing 96.0% of the theoretical maximum.

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