In either unicellular or multi-cellular form, microalgae are photosynthetic microorganisms, mainly known for being part of the human diet in several world regions. More recently, they have been in ...the spotlight of researchers, not only because of their nutritional value, but also due to their high value-added components. This work reviews five microalgae genera: Dunaliella, Botryococcus, Chlamydomonas, Chlorella and Arthrospira, considered among the most promising for commercial biotechnological applications. The analysis shows that, although the research paradigms are generally shared among species, parameterization changes of culture environment and stress conditions, several applications can be envisaged for the cultivated species, which is discussed in this work. Besides, several applications in which these microalgae are being widely used, or are intended to be used, are analyzed and discussed. The potential applications depend on the type of metabolites found in each microalgae species, which is discussed in this work, giving examples of application and describing methods for their cultivation, harvesting and biomass processing. Thus, in addition to being used in human diet supplementation, microalgae can be used as ingredients for animal feed, medicines, cosmetics pigments, biofuels, bioplastics and biostimulants.
•Five microalgae genera considered most promising for commercial applications.•Type of metabolites found in each microalgae species.•Different methods for cultivation, harvesting and biomass processing.•Microalgae promising commercial applications.
Zein is a biodegradable and biocompatible material extracted from renewable resources; it comprises almost 80% of the whole protein content in corn. This review highlights and describes some zein and ...zein-based materials, focusing on biomedical applications. It was demonstrated in this review that the biodegradation and biocompatibility of zein are key parameters for its uses in the food-packing, biomedical and pharmaceutical fields. Furthermore, it was pointed out that the presence of hydrophilic-hydrophobic groups in zein chains is a very important aspect for obtaining material with different hydrophobicities by mixing with other moieties (polymeric or not), but also for obtaining derivatives with different properties. The physical and chemical characteristics and special structure (at the molecular, nano and micro scales) make zein molecules inherently superior to many other polymers from natural sources and synthetic ones. The film-forming property of zein and zein-based materials is important for several applications. The good electrospinnability of zein is important for producing zein and zein-based nanofibers for applications in tissue engineering and drug delivery. The use of zein's hydrolysate peptides for reducing blood pressure is another important issue related to the application of derivatives of zein in the biomedical field. It is pointed out that the biodegradability and biocompatibility of zein and other inherent properties associated with zein's structure allow a myriad of applications of such materials with great potential in the near future.
The supramolecular organization of organic salts has been widely researched, revealing recurring patterns in crystalline lattices that describe their supramolecular properties. In recent years, our ...research group has underscored the importance of considering the crystalline structures as a whole, incorporating all the necessary energetic and topological information for a comprehensive understanding of the crystalline system. Given this context, we investigated a series of ammonium mono- and dicarboxylate salts (
1-12
) to determine whether subtle structural modifications in the anionic organic component lead to relevant energy and topology changes in the crystalline lattice. To achieve this, we selected structures whose carboxylate anion only possesses an alkyl chain and is devoid of other functional groups. The ammonium cation (NH
4
+
) was fixed to determine the effect of variations in the alkyl chains of the selected mono- and dicarboxylates, such as length and degree of unsaturation. Additionally, probable crystallization mechanisms were proposed to elucidate some of the topological and energetic aspects involved in the crystallization of these compounds. Destabilizing interactions were observed in 10 crystalline structures, and the MEP data showed that the most destabilizing interactions occur by the proximity of portions with the same type of charge. Some dimers have unexpectedly low intermolecular interaction energies despite having large contact areas. Based on these data we demonstrate the additivity of intermolecular interactions, that is, the low intermolecular interaction energy in these dimers is the result of the sum of destabilizing energies and stabilizing energies. The cluster energy efficiency data revealed that most crystal lattices display typical characteristics of uncharged organic compounds. The proposed crystallization mechanisms showed a gradual increase in nucleus complexity in the initial stages and the total number of nucleation stages, resulting in five main patterns: monomer → 1D → 3D (
1-2
), monomer → dimer → 2D → 3D (
3
), monomer → 1D → 2D → 3D (
4-5
), monomer → dimer → 3D (
6
), and monomer → 2D → 3D (
7-12
).
The supramolecular organization of organic salts has been widely researched, revealing recurring patterns in crystalline lattices that describe their supramolecular properties.
The quest for understanding crystal structures using supramolecular cluster demarcation has been applied to various uncharged compounds, and, more recently, it has also been applied to charged ...compounds in ammonium salts. Given this context, this study sought to expand this approach for intermediate compounds, between compounds with and without localized charges. The selected structures were mesoionic compounds, which have delocalized charges. This study raises some questions: do mesoionic compounds have intermediate characteristics between salts and uncharged molecules? Or are they similar to one of these models? A molecular and supramolecular investigation of mesoionic models was carried out to answer these questions. The study was based on demarcating the supramolecular cluster, enabling us to propose the crystallization mechanisms of twenty-three mesoionic compounds, in which stabilizing and destabilizing energies were observed. In addition, the Cluster Energy Efficiency (CEE) parameter was applied, allowing us to quantitatively evaluate the similarity between compounds containing both stabilizing and destabilizing energies in the crystalline lattice. The CEE data revealed that most mesoionic compounds have CCE = 1000, a characteristic comportment of uncharged compounds. In addition, the compound 2,3-diphenyl-1,3,4-thiadiazolium-5-thiolate (
18
) was synthesized and characterized to better understand the molecular and supramolecular behavior. Concentration-dependent NMR and LC-MS/MS experiments reveal the first aggregates in solution in the crystallization process of compound
18
. The crystallization mechanisms evidenced six different crystallization patterns, and molecular electrostatic potential (MEP) allowed us to evaluate the different patterns of electrostatic potential dispersion of all compounds.
The quest for understanding crystal structures using supramolecular cluster demarcation has been applied to various uncharged compounds, and, more recently, to charged compounds. So, what would be the supramolecular behavior of mesoionic compounds?
Background
In recent years, aesthetic procedures aiming at body remodeling and have grown exponentially. Cryolipolysis (CLL) has stood out as a noninvasive resource that acts directly on the ...subcutaneous adipose tissue promoting a significant reduction of adipose tissue through of cooling that could lead to the crystallization cytoplasmic lipids, loss of cellular integrity, apoptosis/necrosis of adipocytes, and local inflammation, producing selective loss of adipose tissue. Thus, the objective of the present study was to evaluate the effects of a specific technique of CLL application on the inflammatory reactions of the target tissue in different post‐application times.
Methods
This is a randomized, blind clinical study that evaluated the tissue sample of six patients after 45, 60, and 90 days of an innovative protocol for the application of CLL, with samples collected through abdominoplasty surgeries. The samples were evaluated by immunohistochemical analyses of several markers.
Results
A significantly greater increase in fibroblasts was observed at 45 days and greater phagocytic action at 60 days.
Regarding the apoptosis process, the expression of caspase 3 and cleaved caspase 3 markers varied at different times, with cleaved caspase 3 being higher at 45 and 90 days after CLL application.
Conclusion
The protocol of the CLL presented in this study was able to induce inflammatory responses in addition to confirming the selective apoptotic action at the different times studied.
Several microalgae species have been exploited due to their great biotechnological potential for the production of a range of biomolecules that can be applied in a large variety of industrial ...sectors. However, the major challenge of biotechnological processes is to make them economically viable, through the production of commercially valuable compounds. Most of these compounds are accumulated inside the cells, requiring efficient technologies for their extraction, recovery and purification. Recent improvements approaching physicochemical treatments (e.g., supercritical fluid extraction, ultrasound-assisted extraction, pulsed electric fields, among others) and processes without solvents are seeking to establish sustainable and scalable technologies to obtain target products from microalgae with high efficiency and purity. This article reviews the currently available approaches reported in literature, highlighting some examples covering recent granted patents for the microalgae’s components extraction, recovery and purification, at small and large scales, in accordance with the worldwide trend of transition to bio-based products.
Bryophytes play an important role in the process of ecological succession: conditioning the environment favourably for the emergence of subsequent groups. The objective of this study was to ...investigate the distribution of bryophyte communities in a cronossequence in the Caxiuanã National Forest, Pará, Brazil. To this end, biological material was collected in forest remnants with different successional stages based on regeneration age: Stage I (0 - 10 years), Stage II (10 - 25), Stage III (> 25) and Stage IV (primary forests). Density, richness and composition of species were compared between successional stages and the occurrence of possible indicator-species was investigated. The identified taxa were also classified by guilds of tolerance to solar radiation and colonized substrate. Composition of species was the variable that most contributed to understanding the distribution of bryophyte communities throughout successional stages, with eight species identified as potential indicators of some successional stages. Generalist species predominated in all stages. The richness of sun tolerants, in turn, decreased with the progress of succession, while shade tolerants increased. The land use history and land cover can influence the availability and quality of substrates and consequently their colonization by bryophytes in the different stages.
Abstract Aiming to enrich the knowledge about the flora of savannas, this paper studied the composition and structure of the bryophyte community of Park Savanna areas in Marajó Island - PA. ...Biological material was collected within 60 100-m2 plots equally distributed in the dry season of 2016 and the rainy season of 2017 in five Park Savanna areas (SP-I to SP-V). The composition, density, richness and diversity of species and presence of indicator species were compared between the sampled areas and seasons. The species were classified according to the substrates colonized and ecological groups of light tolerance. Significant differences in SP-V indicated that the area was the main factor influencing the composition of bryophytes (p: 0.0001), with five indicator species. There were also significant differences in density (p = 0.0001168) and richness (p = 0.0001317) of bryophytes between seasons (p-value = 0.3393; p-value = 0.04065; p: 0.1081). There was a predominance of generalist (25 spp.) and corticolous (728 individuals) species, which were widely distributed in the sampled areas. Therefore, the structure of the bryophyte communities was not influenced by seasonality, and this indicates that these plants are adapted to the environmental conditions.
High concentrations of hydrogen peroxide can cause adverse effects on composition and structure of teeth. However, the addition of calcium and fluoride in bleaching agents may reduce enamel ...demineralization. To evaluate chemical changes of sound and demineralized enamels submitted to high concentrations of hydrogen peroxide containing fluoride (F) or calcium (Ca).
Enamel blocks of bovine incisors with standard dimensions were obtained and half of them were submitted to pH-cycling to promote initial enamel caries lesions. Sound and demineralized enamel samples were divided into (n=10): (C) Control (no whitening treatment); (HP) 35% hydrogen peroxide; and two experimental groups: (HPF) 35% HP+0.2% F and (HPC) 35% HP+0.2% Ca. Experimental groups were submitted to two in-office bleaching sessions and agents were applied 3 times for 15 min to each session. The control group was kept in remineralizing solution at 37°C during the bleaching treatment. The surface mineral content of sound and demineralized enamels was determined through Fourier Transform Raman spectroscopy (FT-Raman), Energy dispersive Micro X-ray fluorescence spectroscopy (μ-EDXRF); and the subsurface, through cross-sectional microhardness (CSMH). In addition, polarized light microscopy (PLM) images of enamel subsurface were observed.
According to three-way (FT-Raman and μ-EDXRF analyses) or two-way analysis of variance (ANOVA) (CSMH) and Tukey test (α=5%), the calcium or fluoride added to high-concentrated bleaching agents increased phosphate and carbonate concentrations on sound and demineralized enamels (p<0.05). However, HPC and HPF were unable to completely reverse the subsurface mineral loss promoted by bleaching on sound and demineralized enamels. The calcium/ phosphate (Ca/P) ratio of sound enamel decreased after HP treatment (p<0.001).
Even though experimental bleaching agents with Ca or F reduced mineral loss for both sound and demineralized enamel surfaces, these agents were unable to reverse the enamel subsurface demineralization.
The supramolecular architectures of amide-containing compounds are highly dependent on the side-chain substituents, although the potential impact of isoxazole substituents on polymorph formation has ...not been thoroughly explored. Hence, three distinct forms of N 1 , N 3 -bis(5-methylisoxazol-3-yl)malonamide (1) were obtained and characterized: two polymorphic forms and one solvate. An in-depth analysis of the interactions and energy content of the crystals based on supramolecular clusters allowed us to propose crystallization mechanisms (crystal retrosynthesis). Specifically, the energy similarities between the interaction of the first sites NH amide ⋯OC amide (form 1I) and the symmetric sites NH amide ⋯N isox (form 1II) were found to contribute to their formation. Nonetheless, the presence of DMSO resulted in the formation of form 1III, where the solvent molecule disrupted amide-amide interactions. The first nuclei are more stable than forms 1I and 1II. The compound of N 1 , N 2 -bis(5-methylisoxazol-3-yl)oxalamide (2) was used as a comparison, and through the absence of polymorphs, revealed that the central carbon in molecule 1 allows a flexible adaptation that leads to the three forms. These findings suggest that variations in solvents, flexibility, and the presence/absence of amide–amide interactions can modulate the competition between amide-containing isoxazole compounds.
PDF
