Physical-chemical Analysis Research Articles

Investigation of Physicochemical Properties and Characterization of Leaf Stalk Fibres Extracted from the Caribbean Royal Palm Tree

Synthetic fibres (SF) are replaced by natural fibres (NF) and are utilized as polymer reinforcement owing to their eco-friendliness. The composite has been introduced in the current development by employing NF as reinforcement and stuffing in the polymer matrix (PM). The advantages of using natural resources are being eco-friendly, having plentiful natural availability, higher strength, lower cost, and a simple extrication process. When heated to a specific temperature, certain synthetic products create noxious materials. Therefore, replacing these synthetic substances with natural substances has greater advantages for the environment. In this study, a novel NF extricated from the Caribbean royal palm (CRP) along with its features is determined to replace the harmful SF effectively. The CRP’s leaf stalks, termed CRP leaf stalk fibres (CRPLSFs), are extricated and categorized by (i) thermogravimetric analysis (TGA), (ii) scanning electron microscopy (SEM), (iii) Fourier-transform infrared (FT-IR) spectroscopy, (iv) physical-chemical analysis, (v) X-ray diffraction (XRD), and (vi) tensile test (TT). The physical-chemical characteristics of CRPLSFs, cellulose content (CC), tensile strength (TS), density, and hemicelluloses correlate with other NF characteristics. The CRPLSFs’ chemical components include hemicelluloses (14.52%), lignin (9.15%), and cellulose (61.67%). The TGA shows that the CRPLSFs are thermally stabilized up to 326°C. The XRD proved that the CRPLSFs are enriched with a cellulose fraction comprising a crystallinity index (CI) of 30.27%. The outcomes recommended that the biodegradable coconut peduncle leaf stalk fibres (CPLSF) could be exploited as possible reinforcement in the PM composite structure and can be engaged in making composites.

Fluoride-Doped TiO2 Photocatalyst with Enhanced Activity for Stable Pollutant Degradation

Fluoride-doped TiO2 (F-TiO2) was synthesized by an efficient and simple one-step synthesis and successfully used for the UV-photo-degradation of the toxic and stable pollutants methylene blue (MB) and bisphenol A (BPA). Initially, the synthesized catalyst was characterized and compared to untreated TiO2 (P25 Degussa) by different physical–chemical analyses such as XRD, band gap calculation, SEM, EDS, FITR, ECSA, or EIS. F-TiO2 defeated commercial TiO2, and almost complete pollutant removal was achieved within 30 min. The energy consumption was reduced as a result of the suitable reactor set-up, which reduced light scattering, and by the application of a long-pulse radiation procedure, where the lamp was switched off during periods where the radical degradation continued. This enhanced the overall photocatalysis process performance. Under these conditions, 80% of MB removal was attained within 15 min radiation with an energy consumption of only 0.070 Wh min−1, demonstrating a much better efficiency when compared to previously reported data. The catalyst was reusable, and its performance can be improved by the addition of H2O2. The results were validated by BPA degradation and the treatment of real wastewaters with both pollutants. The results were so encouraging that a scale-up reactor has been proposed for future studies.

Anticoagulant Activity of Heparins from Different Animal Sources are Driven by a Synergistic Combination of Physical-chemical Factors.

Heparin has already been found in a variety of animal tissues but only few of them became effective sources for production of pharmaceutical preparations. Here, we correlate physical-chemical features and anticoagulant activities of structurally similar heparins employed in the past (from bovine lung, HBL), in the present (from porcine intestine, HPI) and in development for future use (from ovine intestine, HOI). Although they indeed have similar composition, our physical-chemical analyses with different chromatography and spectrometric techniques show that both HOI and HBL have molecular size notably lower than HPI and that the proportions of some of their minor saccharide components can vary substantially. Measurements of anticoagulant activities with anti-FIIa and anti-FXa assays confirmed that HPI and HOI have potency similar each other but significantly higher than HBL. Such a lower activity of HBL has been attributed to its reduced molecular size. Considering that HOI also has reduced molecular size, we find that its increased anticoagulant potency might result from an improved affinity to antithrombin (three times higher than HBL) promoted by the high content of N ,3,6-trisulfated glucosamine units, which in turn are directly involved in the heparin-antithrombin binding. Therefore, the anticoagulant activity of different heparins is driven by a balance between different physical-chemical components, especially molecular size and fine-tuning composition. Although such minor but relevant chemical differences reinforce the concept that heparins from different animal sources should indeed be considered as distinct drugs, HOI could be approved for interchangeable use with the gold standard HPI and as a suitable start material for producing new LMWHs.

Physical-chemical analysis of UHT milk samples commercialized in the municipality of Ubá – MG.

Physical-chemical analysis of UHT milk samples commercialized in the municipality of Ubá – MG.

Superior EVOO Quality Production: An RGB Sorting Machine for Olive Classification.

Extra virgin olive oil (EVOO) is a commercial product of high quality, thanks to its nutritional and organoleptic characteristics. The olives ripeness and the choice of harvest time according to their color and size, strongly influences the quality of the EVOO. The physical sorting of olives with machines performing rapid and objective optical selection, impossible by hand, can improve the quality of the final product. The aim of this study concerns the classification of olives into two qualitative classes, based on the maturity stage and the presence of external defects, through an industrial RGB optical sorting prototype, evaluating its performance and comparing the results with those obtained visually by trained operators. EVOOs obtained from classified olives were characterized through chemical, physical-chemical analysis and sensory profile. For the first time, the optoelectronic technologies in an industrial system was tested on olives to produce superior quality EVOO. The selection allows late harvest, obtaining oils with good characteristics from fully ripe and unripe fruits together, separating defective olives with appropriate calibration and training. Optoelectronic selection creates the opportunity to blend the obtained oils destined to different applications according to the needs of the consumer or producer, using a vanguard technology at low cost.

Obtaining brandy from the alcoholic fermented cashew tree, Goiano, Brazil

The process of obtaining the brandy consists of adding yeast to the must to transform the sugar into alcohol, the same microorganism as the fermentation agent. This work aimed to produce brandy from fermented cashew juice and perform physical-chemical analyses. The following analyses of alcohol at 20 °C, pH, total acidity, fixed and volatile were performed, as well as the color parameters in the CIEL system, (L*) luminosity (black/white); (a*) coloring in the red/green region and; (b*) coloring in the yellow/blue range; (c*) Chromaticity is the ratio of a*/b*; (h*) saturation and color angle and; (G*) brightness of the measured color. According to the literature, the results obtained were for alcohol 38.2ºGL and pH 4.53, with an alcoholic degree of 38 to 54% in volume at 20 °C, and its optimum pH for brandy, which is between pH 4.0 and 5.0 at higher levels. The total (38.99) and fixed (3.19) acidity found in this study corroborate the literature regarding volatile acidity, 97.37 mg/100ml of anhydrous alcohol expressed as acetic acid. The L* value (52.59) in the brandy sample presented lighter colors because it was closer to white, as well as the low values of a*(-1.18) and b*(2.47) values evaluated. Chromaticity presented 2.14; chroma defines color intensity, assuming values close to zero for neutral colors (gray) and around 60 for vivid colors. The values obtained for H* were high, whose value obtained 115.51, which characterizes the color of yellow, where hue-angle indicates the saturation of the object's color, is the angle formed between a* and b*. Therefore, they follow the literature and Brazilian legislation based on the results obtained.

Assessment of the influence of a net cage fish culture on the water quality in Furnas reservoir, Brazil

Aquaculture is growing rapidly around the world. In Brazil, fish farming in net tanks has high potential due its large number of reservoirs. However, cultivable areas of tanks with a high fish density may be more susceptible to eutrophication compared to other production systems, and may impair the ecosystem where they are installed. Therefore, attention is needed to this type of system to avoid environmental impacts. The objective of this study was to evaluate the influence of a fish farming in net tanks on the water quality of the Furnas reservoir, Brazil. For physical-chemical analysis, water samples were collected monthly during two production cycles. The results were compared to the limits proposed by the environmental legislation for water bodies in Brazil. It was noted that nitrite and phosphate presented mean values higher than those allowed; however, these results were not associated with fish farming, and there is no influence on the water quality of the Furnas reservoir during the study period. Water quality in the reservoir may be influenced by other activities developed in its basin, such as livestock and intensive agriculture that use many fertilizers, released into the reservoir through runoff.

The study of the optical activity of some S-derivatives 4-R-5-((((3-(pyridin-4-yl)-1H-1,2,4-triazole-5-yl)thio)methyl)-4H-1, 2,4-triazole-3-thiols

About half of the drugs currently produced are chiral compounds, and about 90 % of these compounds are sold as racemates, consisting of an equimolar mixture of two enantiomers. Although they have the same chemical structure, most of the optical isomers of chiral substances show marked differences in biological activity. It is known that the presence of a single asymmetric atom has become almost an integral part of advanced drug design. The aim of this work was to determine the angle of rotation of the polarization plane of solutions of some S-derivatives of 4-R-5-((((3-(pyridin-4-yl)-1H-1,2,4-triazole-5-yl)thio)methyl))-4H-1,2,4-triazole-3-thiols and the establishment of regularities between the structure of the studied molecules and their optical activity. Materials and methods. The subject of the study was 2-[5-R1-4R2-1,2,4-triazole-3-ylthio]-1-aryletanols. The study of the angle of rotation of the plane of polarization of solutions of newly synthesized compounds was carried out using an Atago AP-300 polarimeter and the DFU 2.2.7 physical-chemical analysis method “Optical rotation”. Results. The results of the physical-chemical analysis were carried out that the studied compounds exhibit optical activity. The compound 1-((4-methyl-5-(((3-(pyridin-4-yl)-1H-1,2,4-triazole-5-yl)thio)methyl)-4H-1,2,4-triazole-3-yl)thio)-2-phenylethan-1-ol (+43° [deg∙g/cm3∙dm]). The only levorotatory substance was 1-(4-fluorophenyl)-2-((4-methyl-5-(((3-(pyridin-4-yl)-1H-1,2,4-triazole-5-yl)thio))methyl)-4H-1,2,4-triazole-3-yl)thio)ethan-1-ol with specific rotation [α]D20 = -43° [deg∙g/cm3∙dm]. Conclusions. Studies had shown that 1-(4-fluorophenyl)-2-((4-methyl-5-(((3-(pyridin-4-yl)-1H-1,2,4-triazole-5-yl))thio)methyl)-4H-1,2,4-triazole-3-yl)thio)ethan-1-ol was able to rotate the light polarization plane to the left, which was evidence of the advantage of the S-enantiomer in the racemic mixture, and therefore this compound was considerable interest for further preclinical research. Also, all other analyzed compounds behave as optical isomers.

Modern Sophisticated Instrumental Techniques Used in the Characterization of Bhasma

A nano-metallic drug called Bhasma is created from metal and minerals. It has long been regarded in Ayurveda as a trustworthy and quick-acting dose type. The following procedures—Shodhana, Bhavana, Mardana, and Marana—are used to prepare Bhasma. These processes assist in breaking down particles into their smallest components, get rid of undesirable traits, and give the substance new properties that make them more palatable to the body's tissues and organs. In the classic, various Bhasma Parikshas, such as Varitaratwa, Unnama, Rekha purnatwa, Nirutha, and Apunarbhava, are mentioned. However, these tests are insufficient to determine the safety and efficacy of Bhasma. For the examination of Bhasma, various contemporary factors are used to ensure its acceptance on a global scale like physical evaluation, chemical analysis, and instrumental analysis. Bhasma efficiency is reliant on its homogenous chemical composition, nanocrystalline structure, and biological activity. These highly sophisticated analytical tools, including XRD, SEM, TEM, NTA, ICP-MS, XRF, AAS, and FTIR, are required for the detection of crystal size, particle size, shape, surface area, dispersion state, and morphological features, in addition to chemical and physical properties like reactivity, optical behaviour, magnetism, zeta potential, and others. To understand the toxicity, pharmacokinetics, and pharmacodynamics of Bhasma, all of these methods are employed. As a result, the current paper's main focus is on characterizing Bhasma using modern sophisticated instrumental techniques.

Vicariance Between Cercis siliquastrum L. and Ceratonia siliqua L. Unveiled by the Physical-Chemical Properties of the Leaves' Epicuticular Waxes.

Classically, vicariant phenomena have been essentially identified on the basis of biogeographical and ecological data. Here, we report unequivocal evidences that demonstrate that a physical–chemical characterization of the epicuticular waxes of the surface of plant leaves represents a very powerful strategy to get rich insight into vicariant events. We found vicariant similarity between Cercis siliquastrum L. (family Fabaceae, subfamily Cercidoideae) and Ceratonia siliqua L. (family Fabaceae, subfamily Caesalpinoideae). Both taxa converge in the Mediterranean basin (C. siliquastrum on the north and C. siliqua across the south), in similar habitats (sclerophyll communities of maquis) and climatic profiles. These species are the current representation of their subfamilies in the Mediterranean basin, where they overlap. Because of this biogeographic and ecological similarity, the environmental pattern of both taxa was found to be very significant. The physical–chemical analysis performed on the epicuticular waxes of C. siliquastrum and C. siliqua leaves provided relevant data that confirm the functional proximity between them. A striking resemblance was found in the epicuticular waxes of the abaxial surfaces of C. siliquastrum and C. siliqua leaves in terms of the dominant chemical compounds (1-triacontanol (C30) and 1-octacosanol (C28), respectively), morphology (intricate network of randomly organized nanometer-thick and micrometer-long plates), wettability (superhydrophobic character, with water contact angle values of 167.5 ± 0.5° and 162 ± 3°, respectively), and optical properties (in both species the light reflectance/absorptance of the abaxial surface is significantly higher/lower than that of the adaxial surface, but the overall trend in reflectance is qualitatively similar). These results enable us to include for the first time C. siliqua in the vicariant process exhibited by C. canadensis L., C. griffithii L., and C. siliquastrum.

PHYSICAL-CHEMICAL AND MICROBIAL QUALITY OF THE “CERVEJA CASEIRA” (HOMEBREWED BEER) OF GUARAPUAVA/STATE OF PARANÁ – BRAZIL

“Cerveja caseira” is a homebrewed beer sold in the Guarapuava municipality (State of Paraná, Southern Brazil). It was introduced by Slavic immigrants and adapted to Brazilian ingredients, being much appreciated in the region and disseminated by popular knowledge. The objective of this research is a physical-chemical and microbial analysis of cerveja caseira produced and sold in Guarapuava. Fifty-six samples divided in 14 lots were acquired in October and November 2020 in streets, houses, commerce, and markets of Guarapuava. The physical-chemical analyses included the determination of the following parameters: color, pH, original extract, apparent extract, alcohol, density, bitterness, SO2, and calories. The microbial quality was assessed via counts of total aerobic mesophiles, total and thermotolerant coliforms, positive-coagulase Staphylococcus, Pseudomonas spp, Bacillus spp, molds, and yeasts. The physical-chemical results indicate the lack of standards for the cerveja caseira production, with ample variations regarding color, original and apparent extract, alcohol percentage, and bitterness. Regarding microbial quality, all cerveja caseira lots contained pathogens, mainly mesophiles, yeasts, and Staphylococcus aureus, but no total and thermotolerant coliforms, important contamination indicators. According to Brazilian beer-related regulations, only lot 4 could be commercialized, despite its high percentage of alcohol (2.5% v/v), which characterizes it as an alcoholic beverage, not suitable for consumption by children and adolescents. Cerveja caseira recipes have been passed on from generation to generation, adapted to the climate and to the products available in Brazil, being part of the cultural heritage of the western region of Paraná that should be preserved.

EVALUACIÓN FÍSICO QUÍMICA Y PROTEICA DEL POLEN ALMACENADO EN COLMENAS DE Melipona seminigra, AMAZONAS, BRASIL.

Bee’s pollen comes from the flowers of several species of plants. The grains are transported by worker bees to their nests (honeycombs) to be used as a source of nutrients. The objective of this study was to evaluate the microbiological control, the physical chemical composition and to analyze macro and micro minerals, as well as amino acids in dehydrated pollen hives of Melipona seminigra, in rainy periods (PLL) and dry periods (PS) in Amazonas, Brazil.The physical-chemical composition (proteins, lipids, carbohydrates, fibers and ashes) was performed by the AOAC methodology. In meliponícola pollen it was detected the presence of proteins (35,97 - 36,37 g/100g), lipids (22,37 - 29,66 g/100g), ashes (4,46 - 2,83 g/100g) and ratio carbon/nitrogen (8,94 - 8,28 g/100), also minerals like copper, iron, manganese, calcium, potassium, magnesium and phosphorus were present. In the pollen of the indigenous bees, both non-essential and essential amino acids were found. The results showedthat the meliponícola pollen did not present any contamination for bacteria and fungi that comply with the Brazilian legislation. The physical-chemical analysis confirmed that pollen has nutritional amounts that can be added to other ingredients, providing enrichment of fibers, minerals and proteins to foods at different ages of the population

Physical mechanical and acoustic properties for composite materials made from construction and demolition waste

Environmental protection is an essential human problem and that is why most countries in the world are taking measures to limit it. As we know, pollution is contamination with materials that damage health, quality of life, or the natural functioning of ecosystems. Although some environmental pollution is a result of the action of nature, most are caused by human activity. The disposal of waste from various industrial processes affects the quality of the environment. A particular current problem with environmental pollution is waste as a whole, including construction and demolition waste. Another current problem is noise pollution with negative effects on humans. In this paper, these two problems are addressed through the valorization of these types of waste and the production of composite materials with sound-absorbing properties. Six types of construction and demolition wastes are used and subjected to physical-chemical analysis to determine their moisture content, particle size, and chemical composition. Through an optimized technological process, composite materials were obtained and their sound absorption capacity was determined.

PRODUCTION OF BIODIESEL FROM MARULA SEED OIL USING EGG SHELL AS HETEROGENEOUS CATALYST

Diminishing fossil fuel resources, coupled with the steady increase in energy consumption, and have spurred research interest in alternative and renewable energy sources. In this research work, oil was extracted from marula seeds using soxhlet extractor and n-hexane as solvent. The extracted oil was characterized via physicochemical analysis then in-situ transesterification of oil with methanol was carried out using eggshell as catalyst. The physic-chemical analysis showed the state of the oil at room temperature to be liquid, the odour was mild, the colour was brown, specific density was 3.46, saponification value was 193.6 ± 0.25, acid value was 8.2 ± 0.4, and iodine value was 100.68 ± 1.0. Biodiesel characterization showed that kinematic viscosity at 40oC was 4.98, cetane number was 64.5, flash point was 159, pour point was - 13, cloud point was 5, and density was 0.85. The prepared eggshell catalyst was characterized using X-ray Fluorescence and was found to be composed of CaO (73.2), MgO (0.2), SiO2 (0.4), SO3 (0.3), P2O5 (0.7), Na2O (0.5), Al2O3 (0.07), K2O (0.03), and Fe2O3 (0.08). This study suggests that marula seed oil can be used as a source of triglycerides in the manufacture of biodiesel by transesterification. The properties of the biodiesel produced showed theoretical compatibility with diesel engines in accordance with the ASTM standard.

Multiscale physical–chemical analysis of the impact of fracture networks on weathering: Application to nickel redistribution in the formation of Ni-laterite ores, New Caledonia

Supergene processes related to downward water migration and dissolution of primary minerals in the New Caledonian peridotites result in Ni enrichment at the bottom of the lateritic profile near bedrock. However, the combined effects of relief, lateral fluid flow, and complex inherited discontinuity networks filled by serpentine generate a more complex Ni distribution than a simple flat horizon. In surficial environments, fluid flow and mass transfer are not limited to the vertical scale; they can also be related to lateral fluid circulation and local drainage along damage zones in the vicinity of faults. In this study, we present new structural, petrophysical and geochemical data for core samples to shed light on the impact of a fracture network on the alteration and progression of the Ni-enrichment front during weathering. The analysis of element redistribution by XRF mapping coupled with fracture extraction from computed tomography (CT) establishes that the serpentine fracture network comprises sets of sub-orthogonal fractures whose orientations are potentially determined by pre-existing magmatic foliation. The progression of the olivine dissolution front leads to the redistribution and concentration of Ni into the serpentine fracture network as secondary Mg-Ni talc-like phases. The increase in porosity from < 1 % in the bedrock to > 10 % in the saprock is mainly driven by the formation of nanopores. Nanoporosity may control the development of the weathering front and the redistribution of Ni by small-scale diffusion. Structural and geochemical characteristics identified at the sample scale are analogous to those observed on the larger scale of the outcrop and deposit. Scale invariance in the structural organization and geochemical evolution indicates the potential upscaling of the processes involved in the redistribution of Ni.

Squeezing mind out of metal: combining textual evidence with scientific data for metallurgy in early dynastic China

Since one of the aims of modern archaeometallurgy is to understand the processes carried out by ancient metalworkers, then ideally, we need to go beyond the traditional sources of evidence for such processes — physical investigation and chemical analysis of the objects themselves, and associated manufacturing debris. In order to understand the intentionality behind the decisions taken by these metalworkers (the ‘why’, in addition to the ‘how’), then we need to ‘see the world’ as the metalworkers themselves did. The key issue is how to traverse the gulf between ancient and modern perceptions of the natural world. Using ancient Chinese bronze metalwork as an example, we argue that many interesting glimpses of this world can be drawn from the contemporary and later literary sources. But it is crucial to note that these insights have to be supported by independent evidence, such as scientific data or archaeological information. Once verified, these findings can significantly improve our knowledge of the metaphysical perception of metal in the past and offer a heuristic and powerful tool to interpret the relationship between metallurgy and society. For the Chinese Bronze Age, metallurgy performed a crucial part in the political and ritual world. In particular, the different colours of metal objects provide important indicators of the social hierarchy as evidenced by burial practice.

Sanitary quality of reused water for irrigation in agriculture in Brazil

Reused water is produced from treated effluents, and can be an alternative source of water for agriculture. However, its quality must be assessed to avoid causing damage to human and environmental health. This study evaluated the sanitary quality (bacteriological and physicochemical) of reused water samples for agricultural irrigation, compared with those described in Brazilian and international regulations. Bacteriological analyses were performed, and the results were compared with the norm of the Brazilian Association of Technical Norms (ABNT) NBR nº 13.969/1997. Physical and chemical analyses of the reused water samples were carried out, and the results were compared with the standards described by regulations: Resolution of the State Council for the Environment of Ceará No. 2 of 2017; Resolution of the Bahia State Water Resources Council No. 75 of 2010; and “Guidelines for Water Reuse” from the U.S. Environmental Protection Agency - EPA. According to Brazilian regulations, bacteriological analyses showed that the "chlorinated" and "polished" samples were suitable for agriculture. However, the “biological" sample was unsuitable for use, and showed a high level of thermotolerant coliforms (25.800 CFU / mL). According to bacteriological and physical-chemical analyses, the “polished” sample was only proper for agriculture irrigation. Therefore, the work suggests the creation of federal law regarding agricultural reuse to control the sanitary quality of water for human and environmental health.&#x0D; Keywords: agricultural reuse, agriculture, bacteriological and physicochemical evaluation, norms for reuse in agriculture.

Ocorrência de leite instável não ácido (LINA) em propriedades leiteiras no norte do Tocantins

The diagnosis of unstable non-acid milk (UNAM) in Brazil is overlooked due to the lack of information about this problem available to dairy farmers, mainly in the North region of the country. This report describes the occurrence of UNAM in three dairy farms of family farmers in northern Tocantins state, Brazil, who use animal feed based on Urochloa brizantha without mineral supplementation. The animals had been subjected to a poor feeding practice, with low quantity and quality, due to the dry period in the region and inappropriate nutritional management. Fourteen animals that presented alterations in milk characteristics were subjected to 72% alizarol test, California mastitis test, strip cup test, somatic cell count (SCC), boil test, physical-chemical and microbiological analyses, and search for undesirable substances. The time of lactation, udder health, and serum glucose level of animals, and soil and forage quality were also evaluated. The results showed 42% animals diagnosed with mastitis, 21% of them with clinical and 21% with subclinical mastitis; and 78% of animals with samples positive for the alizarol and boil tests, and Dornic acidity between 14° and 18°, characterizing positive cases for UNAM. Only one animal presented SCC above the limit established by the Brazilian legislation. The animals presented undamaged teats and no alteration in glycemia. Changes in nutritional management were recommended and done and the alizarol tests were redone after 14 days, showing all negative results for UNAM. The conclusion is that incorrect nutritional management is the main cause of UNAN in the studied cases.

Initial Usage of Fish Community to Assess Water Quality in Van Long Wetland Nature Reserve, Ninh Binh Province

Van Long Wetland Nature Reserve is the 9th Ramsar of Vietnam, which has high biodiversity. To assess water quality in this area, the present study initially used the Shannon-Wiener Diversity Index (H') and IBI (Index of Biotic Integrity) of fish community collected in two field surveys in September 2019 and May 2020. A total of 33 fish species belonging to 18 families, 8 orders were determined. The H' index was 1.983 and IBI as 32 indicated that the water quality in the Van Long Wetland Nature Reserve was poor, probably influencing on aquatic organisms. In general, physical-chemical analysis methods revealed that most of the water parameters in the surface layer are good, but many parameters ranged from B1 to A2 levels, especially for TP (Phosphate calculated as P) being at poor level of pollution (B1-B2). Thus, results obtained from both bio-indices and physical-chemical analysis seem similar and indicate that the water in Van Long Wetland Nature Reserve was not completely clean. This finding will contribute to providing data for the conservation of biodiversity and ecotourism development in the reserved area.

Yellow Mombin Nectar Enriched with Encapsulated Green Tea (Camellia Sinensis Var Assamica): Physical-chemical, Rheological and Sensory Aspects

ABSTRACT This research aimed to evaluate the feasibility of applying green tea extract encapsulated in yellow mombin (Spondias mombin L.) nectar. Two formulations were developed: with microencapsulated green tea extract (NM) and control (NC). NM was the variant concentration of green tea microencapsulated (4.6 g of green tea microcapsules for each 240 mL of beverage). The samples were subjected to physical-chemical and bioactive compounds analysis, such as the study of rheological behavior and sensory analysis. The addition of microcapsules resulted in changes in all of the parameters evaluated, highlighting the contribution in antioxidant activity and total phenolic compounds. The inclusion of microcapsules did not influence the rheological behavior. For the sensory analysis, it was found that NC presented better sensory acceptance. The inclusion of microcapsules of green tea extract in yellow mombin nectar presents itself as a viable alternative for the development of a new product.