physicochemical characteristic
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Cereus jamacaru DC. is an endemic cactus of the Brazilian semiarid region empirically used by humans for forage, food and medicinal purposes. In this paper, we characterize the physicochemical and phytochemical profile of the C. jamacaru cladode and fruits, outlining their nutritional implications. We evaluate the basic physicochemical characteristic of the fruits and the main classes of chemical compounds present in aqueous and ethanolic extracts from cladode, peel, and pulp of ripe and semi-ripe fruits through qualitatively and quantitatively methods. We analyze the data through descriptive statistics and variance analysis. The fruits have appropriate pH, acidity, and total soluble solid levels for the fruit processing industry and fresh consumption. We identified the presence of saponins, tannins, flavones, flavonols, and xanthones in all samples, but alkaloids and steroids were both detected in cladodes exclusively. The phenolic compound and flavonoid contents vary according to the extraction method and sample class. The cladodes and pulp of ripe fruits have the highest flavonoid levels, while the content of phenolic compounds had a high level in peels of ripe and semi-ripe fruits. The presence of these bioactive compounds implies that C. jamacaru products have relevant pharmacological interest and functionality for human (fruits) and domestic ruminant (cladodes) food. These applications can boost the agricultural-economic exploration of C. jamacaru and contribute to income generation, and improve human and animal nutrition.

Objectives : Plastic pollution is a very important environmental issue in Korea as well as abroad. The objective of this study is to evaluate the internal and external factors that cause pollution of the coastal environment of Jeju Island using styrene oligomers (SOs) originated from polystyrene (PS) plastic.Methods : In order to achieve the above objective, this study is conducted to quantitatively measure the concentration of 12 individual SOs chemicals, through gas chromatography/mass spectroscopy (GC/MS) analyzing seawater and beach sand samples around sandy beaches in Jeju Island. This study evaluates the degree of environmental pollution according to internal or external factors of the sandy beach by using the physicochemical characteristic that SOs species are adsorbed on the surface of sand particles.Results and Discussion : The average concentration of SOs in the beach sand of Jeju Island ranges from a minimum of 9.80 ng/g to a maximum of 13.62 ng/g, and the average concentration of SOs in seawater is relatively low with a constant 0.05 to 0.11 µg/L. Although the concentration distribution of SOs species differs considerably depending on the sample collected, the concentration of SOs decreases in the order of styrene trimers (7 isomers) > styrene dimers (4 isomers) > styrene monomer. As a result of monitoring, the concentration of SOs at the sandy beaches of Jeju Island is much higher in the beach sand than in the seawater. This result means that the major beaches of Jeju Island can be polluted mainly by internal factors (e.g. population density, number of travelers according to population movement, and so on), because SOs species are adsorbed on the surface of the sand particles and their mobility is limited.Conclusions : This study shows that the sandy beaches of Jeju Island are mainly polluted by internal factors. It is thought that the pollution degree of the sandy beaches is the highest in the order of Gwakji Beach < Samyang Beach, Hamdeok Beach, Pyoseon Beach < Ihoteho Beach, Sagye Beach < Seopjikoji Beach, Gimnyeong Beach, and Hyeopjae Beach. This study is expected to contribute to the evaluation of the causes of plastic pollution in the coastal environment of Jeju Island.

Watermelon rind is a food product that utilize wasted albedo waste. Generally, jam is gel or semi-dense so it has short shelf life. To make the jam more imperishable in storage, preservatives can be added in manufactured progress, one of the preservatives that can be used is sodium benzoate. This research aims to determine the effects of the addition of sodium benzoate on the physicochemical characteristics of watermelon rind jam. The results reveals that the formula of watermelon rind jam with the addition of sodium benzoate has physicochemical content that not much different apart from the one that isn’t added by sodium benzoate. The characteristics that were significantly different were only in viscosity, the jam with the addition of sodium benzoate (6400 cP) was greater than the jam without the addition of sodium benzoate (2900 cP). The selected formula will be tested by organoleptic (hedonic quality) with texture, taste, and aroma attributes with the results that the jam formula was well received by 30 panelists. The quality of watermelon rind jam is identified by color aspect with average score of 5.10 with good category that has brownish yellow color, by texture with average score of 5.10 with good category that has soft and fibrous textured, and by the taste with average score of 5,20 with good category that has sweet acidity taste. Keywords: Watermelon rinds, sensorics analysis

To understand the features and best preparation of sludge activated carbon (SAC), and the pore structure, component, adsorption characteristics, and the yield rate of SAC, many tests have been carried out. The study illustrated that the pore structure was mostly mesopore and amorphous pore such as the ink bottle hole. In terms of different preparations to obtain SAC, the yield of SAC in sample No.1 achieved 88.09%. Using the preparation of ZnCl2 as an activator, the iodine adsorption value was significantly higher than other preparations. However, the content of quartz in sample No.1 achieved a maximum of 52.51%. Charcoal was detected in all samples except sample nos 9-12. The adsorption capacity of Cu(II) and Cd(II) reached a maximum of 600.02 mg.kg-1 and 383.2 mg.kg-1. The results showed an optimum preparation condition, which was by using the ZnCl2 as an activator, 2:1 as the impregnated ratio, 40% concentration in activator and at 400ºC reaction temperature could create rich pore structure and charcoal inside.

Mangrove forests are highly productive ecosystems that sustain marine life, including fish communities. This study aimed to analyse mangrove characteristics, physicochemical parameters, nutrient and primary production derived from mangrove litter and estimate the fish production. The study was conducted at five mangrove sites in North Sumatra and the Aceh Provinces, Indonesia. Two sites represented natural forest at North Sumatra and Aceh (Jaring Halus and Langsa). In comparison, two sites were mangroves converted into oil palm plantations (Pulau Sembilan and Pulau Kampai, North Sumatra). The fifth site was a mangrove forest converted into aquacultural ponds (Percut Sei Tuan, North Sumatra). The study displays the dissemination of mangrove species in five different mangrove sites showing diversity. Avicennia spp found in estuarine near a coastal area, Rhizophora spp spread across the sites, and Sonneratia spp were more likely to occur in the mouth of the upstream river. Litter production at the present study site was dominated by Rhizophora spp., followed by Avicennia spp. This finding was very closely related to the nutrients resulting from litter decomposition in the mangrove ecosystem. The primary production value of 870-1,747 g C m-2 year had a significant role as the beginning of the estuary food chain. Our results show a close association between fish productivity and mangrove management, and conservation status. The highest fish production was found in the well-preserved forests (Jaring Halus and Langsa), followed by the sites converted to palm oil plantations (Pulau Sembilan and Pulau Kampai). At the same time, the least fishing productivity was identified at the fishing ponds (Percut Sei Tuan). The present study provides further evidence of the significant role of mangrove ecosystems for fisheries and calls for effective restoration programs to support local food security along the coast of Indonesia.

The paper considers the issues of studying the structure formation of binders during hardening to determine the optimal moments of mechanical action on gypsum concrete specimens, which makes it possible to optimize the technology of their impregnation with sulfur melt. The time dependence of the elastic modulus of a hardening, binder is its important physicochemical characteristic, since it is used to objectively identify the stages of structure formation, to simulate the processes occurring at each of the stages. It is noted that the method of acoustic resonance of bending vibrations, in the case of hardening binders, needs correction with respect to the measurement technique and interpretation of the results obtained. The kinetics of the resonance frequency of a sample consisting of a rigid cell and a dispersion poured into it is a function of the elastic properties of the cell, the dispersion itself, the contact zone of the dispersion with cell and therefore cannot be used for either qualitative or quantitative analysis of the kinetics of hardening. Taking into account the elasticity of cuvette is necessary to obtain reliable information. It has been established that in the presence of shrinkage or significant expansion of the binder, the study of structure formation by the resonance method should be carried out in plastic cuvettes. Regardless of shrinkage, the use of a cuvette requires compulsory consideration of its elastic properties. It is advisable to objectively distinguish the stages of structure formation on the basis of the kinetics of not the dynamic modulus of elasticity itself, but the rate of its change. The time dependence of the logarithmic damping decrement is also an important characteristic of the concrete structure. The studies carried out make it possible to obtain serogypsum composites with the necessary performance characteristics and to manufacture elements of architectural décor, wall fencing products of increased aesthetics, durability and reliability from them.

The object of research is aqueous dispersions of polysaccharides. One of the most problematic factors is the insufficient study and study of the physicochemical properties of polysaccharides, in particular starch. Among natural polysaccharides, starch occupies a unique position. It has a wide range of applications across many industries and technologies. This is what determines a large number of studies of the state of starch of various botanical origin under the action of various factors that have appeared in the literature recently. Natural polysaccharides, in contrast to synthetic ones, are characterized by a partial ordered structure, formed in the process of synthesis and growth. In the course of the study, a new method of relaxation in starch mixtures was proposed. It was found that structural relaxation in time is slow and long. It was also found that the physicochemical characteristic of polysaccharides, relaxation, is explained by a partially ordered structure with the mutual arrangement of individual chains in a spatial network. It was shown that, under the action of shear stresses, the retest destroys the pseudoplastic liquid structures of aqueous dispersions of starch, followed by restoration to an equilibrium state within 17 hours. The process of recovery or structural relaxation of the spatial structures of aqueous dispersions of polysaccharides occurs due to the rearrangement of the spatial network of the polymer and is formed due to the existence of cross-linked chemical bonds. Thanks to this method of using polysaccharides, it is possible to obtain improved organoleptic, structural, mechanical and physicochemical characteristics of food products. Compared to similar thickeners (pectin, flour), native potato and corn starches provide and provide structural form to products such as sauces, puddings, pastries, minced meat, fish products, and low fat dairy products. In the food system, the role of polysaccharides is to stabilize structure and interact with other components to deliver or maintain nutrients and taste.

Research relevance. Phosphate mining activities are one of the main sources of contamination by heavy metals since they harmfully affect the soil and lead to the degradation of the ecosphere. Research aim. This study aims at characterizing and evaluating the metallic contamination of soils in the vicinity of the Djebel Onk mine in the town of Bir El Ater (Wilaya of Tébessa) in eastern Algeria, and particularly focusing on estimating the spatial variability of this contamination and the extent of the contaminated area. Methodology. The physicochemical characteristic (pH) was determined by pH-meter, whereas AAS was used for the determination of heavy metals (Pb, Cu, Zn, Cd) in the examined soil Research results. The results reveal that soils that are close to the mine site studied and even those that are far away are heavily contaminated with heavy metals — lead (Pb), zinc (Zn), copper (Cu) and cadmium (Cd); the results also point out to a high variability of concentrations not only between sampling sites but also within the same mine site. The analysed soil pollution index is generally high even for soils sampled downstream more than 30 km from the mine site, whereas it is extremely high on the surface of the tailings slopes, underlining the fact that tailings are considered perennial sources of heavy metal contamination in their current state. Conclusion. The unhealthy area affected by metal pollution from mining sites in the Djebel Onk is very large as a result of the dispersion, by wind and water transport, of residual pollutants from the mine wastes abandoned on site. Remediation measures must be put into place to immobilize the pollutants and limit their spread to the environment Keywords: Soil contamination, Algeria, heavy metals, phosphate mine, pollution index.