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101.
Impact of Crude Oil Quality on the Refining Conditions and Composition of Nutraceuticals in Refined Palm Oil
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Klicia A. Sampaio Jose Vila Ayala Vera Van Hoed Simone Monteiro Roberta Ceriani Roland Verhé Antonio J. A. Meirelles 《Journal of food science》2017,82(8):1842-1850
Palm oil is the major vegetable oil used worldwide due to its unique properties. The effect of crude palm oil acidity on the final free fatty acids (FFA) content, neutral oil loss (NOL), and nutraceutical compounds, such as carotenes, total tocols (tocopherols and tocotrienols), squalene, and phytosterols was investigated. A central composite design was employed to study the influence of the refining conditions: temperature (200 to 260 °C), steam percentage (0.5% to 3.5%), and initial FFA content (2.2% to 6.0%) on the quality of the refined product. The results revealed that initial palm oil acidity is a statistically important parameter to obtain commercially acceptable values for final FFA content. The increase of temperature presented the most important effect on the reduction of all nutraceutical compounds. The highest tocopherols (88%), phytosterols (98%), and squalene retention (84%) was obtained when applying the mildest temperature (200 °C). From the experimental results, 3 equations were generated enabling the prediction of the free fatty acids content, the tocols content, and the losses of neutral oil. Therefore, this work contributes to the understanding and optimization of the process for the production of palm oil with high nutraceutical quality and low free fatty acid contents. 相似文献
102.
Aline da Graa Sampaio William Chiappim Noala Vicensoto Moreira Milhan Benedito Botan Neto Rodrigo Pessoa Cristiane Yumi Koga-Ito 《International journal of molecular sciences》2022,23(22)
In this study, different plasma-activated liquids were evaluated for their antimicrobial effects against Escherichia coli, as well as for their cytotoxicity on mammalian cells. The PALs were prepared from distilled (DIS), deionized (DI), filtered (FIL), and tap (TAP) water. Additionally, 0.9% NaCl saline solution (SAL) was plasma-activated. These PALs were prepared using 5 L/min air gliding arc plasma jet for up to 60.0 min of exposure. Subsequently, the physicochemical properties, such as, the oxidation-reduction potential (ORP), the pH, the conductivity, and the total dissolved solids (TDS) were characterized by a water multiparameter. The PALs obtained showed a drastic decrease in the pH with increasing plasma exposure time, in contrast, the conductivity and TDS increased. In a general trend, the UV-vis analyses identified a higher production of the following reactive species of nitrogen and oxygen (RONS), HNO2, H2O2, NO3−, and NO2−. Except for the plasma-activated filtered water (PAW-FIL), where there was a change in the position of NO2− and NO3− at some pHs, The higher production of HNO2 and H2O2-reactive species was observed at a low pH. Finally, the standardized suspensions of Escherichia coli were exposed to PAL for up to 60.0 min. The plasma-activated deionized water (PAW-DI pH 2.5), plasma-activated distilled water (PAW-DIS pH 2.5 and 3), and plasma-activated tap water (PAW-TAP 3.5) showed the best antimicrobial effects at exposure times of 3.0, 10.0, and 30.0 min, respectively. The MTT analysis demonstrated low toxicity of all of the PAL samples. Our results indicate that the plasma activation of different liquids using the gliding arc system can generate specific physicochemical conditions that produce excellent antibacterial effects for E. coli with a safe application, thus bringing future contributions to creating new antimicrobial protocols. 相似文献
103.
Theoretical calculations of radiationless transition probabilities and energies for M-subshell vacancies in Zn, Cd, and Hg are tabulated using the Dirac–Fock method. Transition probabilities between an initial vacancy state and a final two-vacancies state are presented for each initial and final atomic angular momentum quantum number. Calculations were performed in the single configuration approach with the Breit interaction, self-energy and (Uehling) vacuum polarization corrections included in the self-consistent method. Higher-order retardation corrections and QED effects were also included as perturbations. 相似文献
104.
Emilio Insfran Gary Chastek Patrick Donohoe Julio César Sampaio do Prado Leite 《Requirements Engineering》2014,19(4):331-332
Many attempts have been made to increase the productivity and quality of software products based on software reuse. Software product line practice is one such approach, one that focuses on developing a family of products which have a majority of features in common. Hence, there are numerous requirements that are common across the family, but others are unique to individual products. Traditional requirements engineering methods were conceived to deal with single product requirements and are usually not flexible enough to address the needs arising from reusing requirements for a family of products. There is also the additional burden of correctly identifying and engineering both product-line-wide requirements and product-specific requirements as well as evolving them. Therefore, in this special issue, we want to highlight the importance and the role of requirements engineering for product line development as well as to provide insights into the state of the art in the field. 相似文献
105.
106.
Yara S. de Queiroz Patrícia B. Antunes Silvio J. V. Vicente Geni R. Sampaio Julianna Shibao Deborah H. M. Bastos Elizabeth A. F. da S. Torres 《International Journal of Food Science & Technology》2014,49(5):1308-1314
Garlic is used in many dishes but some of its bioactive compounds are lost when exposed to heat. This study evaluated bioactive compounds, antioxidant activity and Maillard reaction products of raw (RG), boiled (BG) and fried garlic (FG). Total phenolic compounds, flavonoids, allicin and phytosterol were quantified as well as dietary fibres and mineral content. Antioxidant activities of RG, BG and FG were evaluated by oxygen radical absorbance capacity (ORAC), oxidation of β‐carotene/linoleic acid and Rancimat methods. The main results were the following: thermal processing of RG decreased both bioactive compounds and antioxidant capacity, boiling was found to be less aggressive than frying, and strong correlations were obtained between total phenolic compounds and the antioxidant assays. However, phytosterol content was higher in FG than in RG and BG and higher temperatures increased the formation of Maillard reaction products. It was concluded that RG and BG should be preferred for human consumption as they present higher antioxidant capacity. 相似文献
107.
Patrícia Sampaio Tavares Veras Juliana Perrone Bezerra de Menezes 《International journal of molecular sciences》2016,17(8)
Leishmania is a protozoan parasite that causes a wide range of different clinical manifestations in mammalian hosts. It is a major public health risk on different continents and represents one of the most important neglected diseases. Due to the high toxicity of the drugs currently used, and in the light of increasing drug resistance, there is a critical need to develop new drugs and vaccines to control Leishmania infection. Over the past few years, proteomics has become an important tool to understand the underlying biology of Leishmania parasites and host interaction. The large-scale study of proteins, both in parasites and within the host in response to infection, can accelerate the discovery of new therapeutic targets. By studying the proteomes of host cells and tissues infected with Leishmania, as well as changes in protein profiles among promastigotes and amastigotes, scientists hope to better understand the biology involved in the parasite survival and the host-parasite interaction. This review demonstrates the feasibility of proteomics as an approach to identify new proteins involved in Leishmania differentiation and intracellular survival. 相似文献
108.
109.
SM Serrano Y Hagiwara N Murayama S Higuchi R Mentele CA Sampaio AC Camargo E Fink 《Canadian Metallurgical Quarterly》1998,251(3):845-853
Two forms of a proteinase, KN-BJ 1 and 2, were purified to homogeneity from the venom of Bothrops jararaca. In SDS/PAGE reduced KN-BJ 1 and 2 migrated as single bands with molecular masses of 38 kDa and 39 kDa. The two enzymes have similar N-terminal amino acid sequences and specific activities on synthetic chromogenic substrates, and both release bradykinin from bovine low-molecular-mass kininogen. KN-BJ 1 and KN-BJ 2 clot fibrinogen with specific activities of 245 NIH U/mg and 219 NIH U/mg, releasing only fibrinopeptide A. The amidolytic, kinin-releasing and coagulant activities are inhibited by phenylmethylsulfonyl fluoride, demonstrating that KN-BJ is a serine proteinase. Benzamidine derivatives, which are competitive inhibitors of trypsin-like proteinases, also inhibited the amidolytic activity of KN-BJ. A cDNA clone (HS104, 2.2 kb) has been isolated from a cDNA library of B. jararaca venom glands with an ORF of 771 bp. The deduced amino acid sequence contains segments that are identical to the sequences of the N-terminus and three tryptic peptides of KN-BJ 2. Therefore, the cDNA is believed to represent the gene of KN-BJ 2. The deduced amino acid sequence indicates that KN-BJ 2 is synthesized as a prezymogen of 257 amino acids with a putative signal peptide of 18 amino acids and an activating peptide of six amino acid residues. The sequence of 233 amino acids representing the mature enzyme exhibits high similarity to sequences of serine proteinases isolated from crotalid venoms. 相似文献
110.
In this paper we describe an algebraic approach to construct provably correct compilers for object-oriented languages; this
is illustrated for programs written in a language similar to a sequential subset of Java. It includes recursive classes, inheritance,
dynamic binding, recursion, type casts and test, assignment, and class-based visibility, but a copy semantics. In our approach,
we tackle the problem of compiler correctness by reducing the task of compilation to that of program refinement. Compilation
is identified with the reduction of a source program to a normal form that models the execution of object code. The normal
form is generated by a series of correctness-preserving transformations that are proved sound from the basic laws of the language;
therefore it is correct by construction. The main advantages of our approach are the characterisation of compilation within
a uniform framework, where comparisons and translations between semantics are avoided, and the modularity and extensibility
of the resulting compiler. 相似文献