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The purpose of this study is to extract psyllium mucilage and evaluate its antioxidant compounds (in the best extraction condition) and its application in a chocolate drink.

First, the extraction by ultrasonic bath was evaluated, followed by water bath extraction, and as there was no difference between the methods, a water bath experimental design was carried out to evaluate the best extraction conditions for psyllium mucilage, having response variables, yield and emulsion stability. A chocolate drink with psyllium mucilage was produced and evaluated in the best extraction condition to compare with xanthan gum.

The best extraction conditions for psyllium mucilage were 60°C for 2 h and 1:80 ratio (seed:water). It can be verified that psyllium is rich in antioxidant compounds (0.71 mg GAE/g and 6.67 Mmol ET/g by 2,2′-azinobis (3-ethylbenzthiazoline sulfonic acid-6), and 9.65 Mmol ET/g for ferric reducing antioxidant power), which can greatly contribute to its application in food products. The use of mucilage in chocolate drink is feasible, as among its several attributes there was no significant difference between samples, highlighting texture attributes in which mucilage samples did not differ from the control containing xanthan gum (being the grades approximated 6.84).

Psyllium presented several antioxidant compounds that are very desirable in food products. In the chocolate drink, psyllium mucilage showed potential use as a thickener, so it is important for further studies to improve the product’s development, but it is currently feasible to be produced in an industrial scale.

The mucilage of the Linum usitatissimum L. seed (Linseed) is one of the natural mucilages that presents a great potential to provide a food hydrocolloid with potential applications in both food and pharmaceutical industries. To increase the yield and quality of linseed oil during its production process, it is necessary to previously extract its polysaccharides. Because of this, flax mucilage production can be made viable as a byproduct of oil extraction process, which is already a product of high commercial value consolidated in the market. Thus, the purpose of this work is to optimize the mucilage extraction process of L. usitatissimum L. using the normal-boundary intersection (NBI) multiobjective optimization method.

Currently, the variables of the process of polysaccharide extraction from different sources are optimized using the response surface methodology. However, when the optimal points of the responses are conflicting it is necessary to study the best conditions to achieve a balance between these conflicting objectives (trade-offs) and to explore the available options it is necessary to formulate an optimization problem with multiple objectives. The multiobjective optimization method used in this work was the NBI developed to find uniformly distributed and continuous Pareto optimal solutions for a nonlinear multiobjective problem.

The optimum extraction point to obtain the maximum fiber concentration in the extracted material was pH 3.81, temperature of 46°C, time of 13.46 h. The maximum extraction yield of flaxseed was pH 6.45, temperature of 65°C, time of 14.41 h. This result confirms the trade-off relationship between the objectives. NBI approach was able to find uniformly distributed Pareto optimal solutions, which allows to analyze the behavior of the trade-off relationship. Thus, the decision-maker can set extraction conditions to achieve desired characteristics in mucilage.

The novelty of this paper is to confirm the existence of a trade-off relationship between the productivity parameter (yield) and the quality parameter (fiber concentration in the extracted material) during the flaxseed mucilage extraction process. The NBI approach was able to find uniformly distributed Pareto optimal solutions, which allows us to analyze the behavior of the trade-off relationship. This allows the decision-making to the extraction conditions according to the desired characteristics of the final product, thus being able to direct the extraction for the best applicability of the mucilage.

This paper aims to present experimental results related to the performance of cactus mucilage (CM) and brown seaweed extracts (SEs) to inhibit reinforcing steel bar (rebar) corrosion in saturated calcium hydroxide alkaline solutions (pH = 12.5).

Electrochemical cells were prepared using CM solutions at 0.5, 1 and 1.38 per cent concentration (w/v), SE solutions at 0.5, 1, 1.38, 2 and 3 per cent concentration (w/v), sodium alginate at 1 per cent concentration (w/v) and calcium nitrite at 11.3 per cent (v/v). Each cell contained six deformed reinforcing steel bars of 9.5 mm nominal diameter. The experiments were performed at 23 ± 2°C in two stages. The first stage was aimed at stabilizing the rebar until passivation was reached. The second stage included adding NaCl in six steps from 0.5 to 16 g/L. Half-cell potential, linear polarization resistance and electrochemical impedance spectroscopy measurements were monitored during both stages.

The electrochemical test results indicated that both additions reduce the corrosion rate of rebars and pitting in an alkaline media with chloride ions (16 g/L NaCl). Electrochemical impedance spectroscopy results for rebars in natural-added solutions showed higher charge transfer resistance and double layer capacitance values, indicative of the formation of a second interface between the rebar and the electrolyte.

The information obtained was for alkaline solutions only. Further investigation is performed using concrete as the alkaline electrolyte.

CM and SE may be suitable low-cost corrosion inhibitors for steel in concrete.

The use of botanical or algae products for this application will encourage people to consider its production for this particular application. Also, the possible harvest in an environmental friendly way will diminish in the future the use of biohazards and toxic inhibitors.

This investigation is a continuation of a one presented in 2007, which uses only nopal mucilage. This new investigation corroborates what was concluded in the early investigation and incorporates a new natural by product, algae, as a possible corrosion inhibitor product.

The purpose of this paper is to determine if a type of cactus mucilage, Opuntia ficus-indica (OFI), may act as a corrosion inhibitor for carbon steel in cement-based materials (mortar) exposed to chloride-laden environment.

Mortar prisms, reinforced with carbon steel rods, were immersed in sodium chloride (NaCl) solution for five wet – dry cycles. The experimentation included electrochemical monitoring (corrosion potential, Ecorr, and polarization resistance, Rp) of carbon steel during the time of exposure until corrosion-induced cracking appeared at the mortar surface. Crack survey on the mortar prisms was performed. Carbon steel rods were retrieved from the mortar after crack survey and steel mass loss at the end of the experimental period was estimated. A comparison between the different mixtures was also performed.

OFI mucilage did perform as a corrosion inhibitor of steel in chloride contaminated mortar.

The experimental program needs to be corroborated in concrete specimens with typical dimensions. The surface oxide/hydroxide formation of the carbon steel in contact with the OFI mucilage is still unknown; thus, electrochemical impedance spectroscopy (EIS) and X-ray diffraction (XRD) analyses are needed.

OFI mucilage is a suitable natural product that can be used to increase durability of concrete structures not only in countries where OFI cactus is produced, but also in many other countries where this plant is considered a plague.

The new information obtained from this paper is the innovative use of a by-product of this cactus plant for construction industry applications.

Production of oil from Camelina sativa seed (CS) by pressing yields a by‐product in the form of press cakes (PC). The PC were traditionally used as ingredient in fodder for animals. This paper aims to estimate the nutritional value of CS and PC with regard to exploitation in human nutrition.

Seed samples for analyses were collected from remote locations in Europe and in Scandinavia. The analyses of CS for the content of carbohydrates, vitamins and minerals were carried out using advanced analytical technology. With few exceptions, standard analytical methods were used.

The analyses quantified the content of carbohydrates, vitamins and minerals of CS. The mean content of glucose was 0.42 per cent, fructose 0.04 per cent, sucrose 5.5 per cent, raffinose 0.64 per cent, stachyose 0.36 per cent, starch 1.21 per cent, pectin 0.96 per cent, mucilage 6.7 per cent, crude fibre 12.8 per cent and lignin was 7.4 per cent. The analyses for vitamins were restricted to water soluble vitamins of B series. The content of thiamin (B1) was 18.8  μg/g, riboflavin (B2) 4.4  μg/g, niacin (B3) 194  μg/g, pantothenic acid (B5) 11.3  μg/g, pyridoxine (B6) 1.9  μg/g, biotin (B7) 1.0  μg/g and folate (B9) 3.2  μg/g. Analyses for selected minerals disclosed the content of calcium (Ca) 1.0 per cent, magnesium (Mg) 0.51 per cent, sodium (Na) 0.06 per cent, potassium (K) 1.6 per cent, chlorine (Cl) 0.04 per cent, phosphorus (P) 1.4 per cent, sulphur (S) 0.24 per cent, iron (Fe) 329  μg/g, copper (Cu) 9.9  μg/g, manganese (Mn) 40  μg/g, nickel (Ni) 1.9  μg/g and zinc (Zn) 69  μg/g.

The available scientific documentation does not provide information concerning analyses of CS for the content of carbohydrates, vitamins and minerals. The present investigation reveals the quantitative contribution of these substances to the total nutritional value of CS. Chemical characteristics and the role of the respective substances in metabolism are briefly reviewed.

The importance of nutraceuticals and functional foods has been a topic of interest in nutrition research for many years. This review aims to summarize the findings on the nutritive value and health benefits of chia, as well as its use as a food fortificant.

Published literature on the nutritive value and therapeutic properties of chia has been reviewed.

Chia, an ancient grain, belongs to the mint family (Lamiaceae) and was cultivated in Mexico and Guatemala by the Mayas and Aztecs of a pre-Columbian era. In addition to being gluten-free, chia seeds are concentrated source of omega-3 fatty acids (mainly α-linolenic acid), fiber (insoluble) and polyphenolic compounds (myricetin, quercetin, kaempferol, chlorogenic and caffeic acids), which were found to be comparatively higher than many other grains, cereals and oily seeds. Chia supplementation has potential to lower incidence of cardiovascular disease, obesity, hypertension, cancer, diabetes, pruritus and celiac disease. Because of its nutraceutical and physiochemical properties, chia has been widely used as a whole seed, flour, seed mucilage, gel and oil for developing various enriched food products, such as bread, pasta, cakes, cookies, chips, cheese, yoghurt, meat, fish and poultry.

With advancement in nutrition research, chia would have a great future perspective as feed, food and medicine. However, further research is needed to validate the potential therapeutic effect of chia supplementation on human health.

The purpose of this paper is to discuss the design and fabrication of magnetic couplings to use for vacuum robots. The permanent magnetic coupling (PMC) is appropriate for torque transmission in ultrahigh vacuum and highly clean environments. However, conventional structures of PMC are always unsuitable to use for vacuum robots.

Two types of design scheme for radial magnetic couplings are introduced and compared. The major characteristic of the novel design scheme is that the inner part uses a nonmagnetic mantle to enclose the magnets and yoke, and the outer part uses two end closures to position magnets. The locating groove on the end closure may be manufactured as T‐shape or dovetail shape.

The 3D finite element analysis simulation results and experimental studies have demonstrated that the proposed Design B had a lower contamination rate and a higher transmission efficiency than the Design A.

The limitation of the research to date is that issues of control, path‐planning, and communication have not yet been addressed.

The proposed PMC is successfully applied in vacuum robots which uses combined direct drive techniques and magnetic transmit techniques.

These results suggest that the proposed PMC is suitable for using in vacuum robots.

The purpose of this paper is to evaluate the physico‐chemical properties of African star apple (Chrysophylum albidum) components. African star apples are among the under‐utilized fruits in Nigeria therefore, the four succulent components (peel, pulp, juice and pericarp) of the fruit were analyzed and compared with other known fruits.

African star apples were purchased and divided into two portions. The first portion was washed and the juice was expressed manually into a bottle and covered, while in the second portion, the peel, pulp and the pericarp (mucilage on the seeds) were separated. The physico‐chemical analyses (moisture, total solid, pH, titratable acidity, total sugar, carotenoids, ascorbic acid and total soluble solids) were carried out on the four components.

Moisture content ranged from 53.5 per cent in peel to 86.3 per cent in juice, while the peel had higher total solid and the least was in the juice. The pH of peel was lower than that of other components. The peel had lower titratable acidity (1.2 per cent) and sugar (0.9 Brix) while the juice had higher value (5.4 Brix) in sugar and 15.0 mg/100 g carotenoid. The juice was rich in ascorbic acid (28.5 mg/100 g) followed by the pulp (25.0 mg/100 g). The pulp had higher total soluble solids (24.8 per cent) and the least was in the pericarp (9.8 per cent).

The physico‐chemical properties of the African star apple fruit gave an indication of the usefulness of this fruit in brewing industry especially for wine making and jelly or jam manufacture. Processing of this fruit will curb wastage during its season and make it available in different form.

This paper aims to evaluate the antimicrobial and antioxidant activity of ethanol, methanol and aqueous extracts of the jujube fruit.

The fruit samples were harvested from Ziziphus lotus L. in three regions of Morocco: Aïn Chifae (Immouzer), Saiss (Fez) and Guercif. The fruit extracts were obtained by Soxhlet method using ethanol, methanol and water, and then a phytochemical screening was done for each extract. Total phenolic and total flavonoids contents were also determined. Afterward, the antimicrobial activity of the studied extracts was evaluated using the broth microdilution method. To estimate the total antioxidant effect of these extracts, the DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging and phosphomolybdate tests were performed.

Results showed that the highest content of polyphenols and flavonoids was found for ethanol and methanol extracts, while the lowest content was found in the aqueous extracts for all populations studied. Thus, results showed that the highest content of phenolic compounds was recorded in the population of Fez. Methanol extract of this population was the richest in polyphenols (30.36 mg/g) and in flavonoids (13.03 mg/g). The antimicrobial tests showed that Enterococcus faecalis and Pseudomonas aeruginosa were the most sensitive (6.25 mg/ml), compared to the other tested strains. Based on the minimal bactericidal concentrations/minimal fungicidal concentration or MFC/MIC ratio, it seems that ethanol extracts showed a bactericidal effect against Escherichia coli, Staphylococcus aureus and Bacillus subtillis, and a bacteriostatic effect against Enterococcus faecalis. On the other hand, the methanol extract showed bacteriostatic effect against Enterococcus faecalis and Pseudomonas aeruginosa. In addition, methanol extracts of Ziziphus lotus have significant antioxidant potent.

Methanol and ethanol extracts of Ziziphus lotus fruit have demonstrated strong antimicrobial effect. Moreover, the authors were able to show that the extract of Ziziphus lotus fruit has a very important antioxidant power.

In recent years, the use of earth as a material applied to construction has been adapted as an attractive alternative to modern concepts. The earth construction technique takes advantage of regional natural resources, among which are earth bricks. The purpose of this paper is to analyze the effect of the addition of coconut fibers and aloe vera on the mechanical properties of compressed earth blocks (CEB).

CEBs were manufactured from silty and clay soil (Altamira, Tamaulipas, Mexico) with biodegradable stabilizers of aloe vera and short coconut mesocarp fibers, which were compared with the conventional mixture with lime as stabilizer. The samples were subjected to compression tests (Mexican Standard NMX-C-404-ONNCC3-205), flexion (NMX-C083-ONNCCE.), abrasion (NTC-5324 3.4.3), water absorption (NMX-C-37-ONNCE-205), surface morphology and thermal properties (ASTM D5334-14).

It was found that the addition of coconut fibers has a 12% difference in flexural strength. The addition of 0.5% of coconut fibers decreases swelling by 2% with water and reduces the thermal conductivity of the material by 12%. Likewise, this mixture increases the abrasion resistance of CEB by 30%. When there is a pressure greater than 1,700 psi in the CEB, the addition of coconut fibers does increase the compressive strength of the material, showing a 34% improvement over the CEB without adding coconut fibers.

The authors show a new sustainable CEB production with aloe vera and coconut fiber that is possible for self-production with better mechanical properties than others, commonly produced in Mexico.