A Taguchi design approach for the enhancement of a detergent-biocompatible alkaline thermostable protease production by Streptomyces mutabilis strain TN-X30

The ability of microorganisms to grow at high temperature, alkaline pH, and high salinity makes them an attractive target for enzyme-production with several industrial applications. One strain TN-X30 has been selected as protease producer and identified as Streptomyces mutabilis after a phenotypic and molecular study. Its production of protease was improved using Taguchi L27 design. The strategy was carried out to identify the optimum levels and the interaction of the screened factors. Following this step, maximum protease activity (10,895 U/ml) was achieved after 6-days of incubation. The TN-X30 protease activity had an optimum of pH and temperature of 10 and 65°C, respectively. Thermodynamic parameters at 60°C were enthalpy 14.26 kJ/mol, entropy −220 J/mol/K, and Gibbs free energy 90.53 kJ/mol. TN-X30 protease production displayed a 16-fold increase reaching 175,000 U/ml in a 100-L fermentor. Furthermore, the lyophilization in presence of sorbitol enhanced the stability of the TN-X30 protease which remained active at 75% after 24-months of storage. The lyophilized TN-X30 protease exhibited exceptional stability indexes in presence of some known commercialized detergent components as NEODOL® 25-7, Dehydol® LT 7, Na₂ CMC, Galaxy LAS, Galaxy LES 70, Galaxy 110, Galaxy CAPB Plus, and Sulfacid K. The lyophilized enzyme also displayed high stability with respect to both solid and liquid detergents. Finally, TN-X30 protease exhibited remarkable destaining of blood, egg, and chocolate stained cloth pieces. These findings may promote TN-X30 protease for use as bioadditive in detergent formulation, thereby reducing environmental chemical threat.     

Study of Heat Effect on the Composition of Dunes Sand of Ouargla (Algeria) Using XRD and FTIR

The spectra of x-ray diffraction (XRD) and infrared spectroscopy (FTIR) shows that the dunes sand of Ouargla’s region consists naturally of crystalline structures of α-quartz and gypsum, as well as other uncrystallized compounds with low concentrations like kaolinite and hematite, in addition to some organic compounds. The sand heating process at temperatures between 200 and 1200 °C affects its composition. By heating at 200 °C crystalline phases of anhydrite and bassanite appear due to the continuing loss of water from the gypsum. All the gypsum transforms into anhydrite, and the kaolinite transforms into metakaolin because of the breaking of the OH bond, producing water vapor by heating in the range of 400–800 °C. The heating at 1000 °C disassembles the kaolinite into aluminium-silicon and cristobalite, and leads to the emergence of a new crystalline phase related to wollastonite resulting from the start of a reaction between the anhydride and the quartz. Heating at 1200 °C leads to the disappearance of all the anhydrite because of its interaction with the quartz, producing the wollastonite and the release of sulfur dioxide SO₂ and oxygen O₂, in addition to the increase of the cristobalite proportion because of the disintegration of all the kaolinite into mullite and cristobalite, or the transformation of quartz phase into cristobalite. Also occuring is an interaction between the hematite and the quartz producing the ferrosilite characterized by its green color.     

Fatty acid profiles, antioxidant compounds and antiradical properties of Pinus halepensis Mill. cones and seeds

BACKGROUND: Pinus halepensis (Aleppo pine) is a widespread tree that can be found in both natural and urban environments. A discrimination study based on the antioxidant compounds, antioxidant capacity and fatty acid (FA) profile of P. halepensis cones (PHC) and seeds (PHS) was performed. RESULTS: The total amount of phenols was about 72‐fold higher in PHC extract than in PHS extract (P < 0.001). Anthocyanin and carotenoid contents were 10‐ and 12‐fold higher respectively in PHC extract. PHC and PHS extracts at a concentration of 1 mg mL^?1 differed significantly in free radical‐scavenging activity on 2,2‐diphenyl‐1‐picrylhydrazyl radical (DPPH^?) (86.65 vs 16.97%). PHC had higher antioxidant ability on 2,2′‐azino‐bis(3‐ethylbenzothialozine‐6‐sulfonic acid) radical cation (ABTS^?+) than PHS (EC₅₀ 0.368 vs 2.345 mg mL^?1). The FA profile of PHC oil revealed its richness in saturated FAs (41.5%) and high levels of trans FA isomers, with a predominance of trans,trans ‐linoleic acid (4.74%). However, polyunsaturated FAs in PHS oil represented more than 64% of total FAs. CONCLUSION: PHC showed important antioxidant activities as well as high levels of bioactive compounds. Thus PHC is a potential source of natural antioxidants that may afford several health benefits. However, the lipid extract of PHS seems to have more nutritional value as a polyunsaturated oil than that of PHC, which is high in saturated and trans FAs. Copyright © 2011 Society of Chemical Industry     

Enhancement of Antioxidants in Olive Oil by Foliar Fertilization of Olive Trees

Oxidative stability (OS) of virgin olive oil is affected by different antioxidants whose levels may be influenced by nutrients availability. Changes in OS of virgin olive oil and antioxidants levels were evaluated according to foliar application of six nutrient-based treatments: T1 (rich in nitrogen), T2 (rich in boron, magnesium, sulfur and manganese), T3 (rich in phosphorus and potassium), T4 (rich in phosphorus and calcium), T5 (application of T1 and T2) and T6 (application of T1, T2, T3 and T4). The foliar applications were carried out during two successive growing seasons and oils were extracted and analyzed at the end of the experiment (after 2 years). T3 and T6 treatments improved oil stability by increasing the content of antioxidants, while T2 and T4 affected negatively the antioxidant profile of oils. Measured correlations between OS and compositional variables showed that total phenols had the highest value (R = 0.937, p < 0.001), followed by α-tocopherol (R = 0.775, p < 0.001) and oleic/linoleic ratio (R = 0.625, p < 0.05). These findings suggest that the changing levels of antioxidant compounds, due to fertilization, may be used to obtain oils with the highest quality.     

Chromatic Classification of Ouargla (Algeria) Dunes Sand: Determination of Main Compositions and Color Causes,by Using XRD,FTIR and XRF

In the present work, a manually chromatic classification of Ouargla dunes sand has been carried out. According to its visual color, eight chromatic types of sand have been obtained: transparent (yellow, orange and red), and opaque (white, milky, gray, black and red). According to the main chemical compositions of sand, both XRD and FTIR have divided the chromatically sorted sand into three groups: quartzite (transparent samples), calcareous (milky, gray and black opaque samples) and calcareous quartzite (white and red opaque samples), without possibility of distinguishing between the sorted samples. FTIR spectroscopy has shown all functional groups and vibration modes in these samples. XRF spectroscopy has shown that sand grain colors are closely related to the main compositions as well as the impurities. It has also been shown that transparent samples contain more than 92 % of quartz (SiO ₂). The redness of transparent samples is proportional to iron (Fe) impurities. It has also been shown that milky, gray and black opaque samples contain more than 55 % of calcium oxide (CaO). The milky color is due to magnesium (Mg) and sulfur (S), whereas the blackness is due to iron (Fe) and manganese (Mn). Both white and red opaque samples contain approximately equal concentrations of quartz and calcite, whilst the redness refers to the high concentration of iron (Fe), whereas the whiteness is due to the presence of magnesium (Mg).     

Qualitative and Quantitative Evaluation of Quartz in Different Granular Types of Ouargla Region Sand Dunes – Algeria

In this paper, it is shown that Ouargla region (Algeria) sand dunes are very rich in quartz. This study aims to assess the quartz in the different granular sand types, using XRD spectroscopy. Granulometric classification and the size distribution curve were carried out. The X’Pert HighScore program based on the Rietveld refinement was used in analyzing the XRD data. Qualitative and quantitative quartz evaluations were carried out. It was deduced that the quartz was of the α phase. The concentrations of quartz have been calculated as: the very fine sand (0.063-0.100 mm) possessing the highest value of 82.05 %, followed by the coarse sand (0.500-1.000 mm) with 78 %, while in both the medium (0.250-0.500 mm) and the fine (0.100-0.250 mm) the concentration was about 67 %, whereas, the lowest one was 18.2 % in the very coarse sand (1-2 mm). These results were confirmed by FTIR spectroscopy. Crystallite sizes of quartz have been estimated, and their distribution curve versus grain sizes has been illustrated. It was found that the crystallite sizes in the fine sand are less than 100 nm, and thus may be considered as nanometric particles.     

Fatty acid profile,sugar composition,and antioxidant compounds of table olives as affected by different treatments

The influence of cultivar and processing on olive antioxidants, fatty acids, and sugars profiles were studied for the autochthonous Meski and two introduced table olives (Picholine and Manzanella). Olive fruits were treated with two traditional Tunisian processes. Fatty acid analysis by capillary gas chromatography, total phenols and o-diphenols, and sugars profiles by GC and GC–MS, together with oxidative capacity, were evaluated. Independently of the processing method, the olive fruit showed significant cultivar dependant differences. Concerning the effect of processing, ANOVA tests showed no significant difference in the fatty acid profiles, whereas sugars and phenols underwent a sharp decrease during the fruit storage.