Gutierrez Rodrigues de Morais

Liquid nitrogen pretreatment of eucalyptus sawdust and rice hull for enhanced enzymatic saccharification.

In this work, liquid nitrogen was used for the first time in the pretreatment of plant biomasses for purposes of enzymatic saccharification. After treatment (cryocrushing), the initial rates of the enzymatic hydrolysis of eucalyptus sawdust and rice hull were increased more than ten-fold. Cryocrushing did not modify significantly the contents of cellulose, hemicellulose and lignin in both eucalyptus sawdust and rice hulls. However, substantial disorganization of the lignocellulosic materials in consequence of the pretreatment could be observed by electron microscopy. Cryocrushing was highly efficient in improving the saccharification of the holocellulose component of the plant biomasses (from 4.3% to 54.1% for eucalyptus sawdust and from 3.9% to 40.6% for rice hull). It is important to emphasize that it consists in a simple operation with low requirements of water and chemicals, no corrosion, no release of products such as soluble phenolics, furfural and hydroxymethylfurfural and no waste generation.

Stryphnodendron adstringens: Clarifying Wound Healing in Streptozotocin-Induced Diabetic Rats.

Diabetes mellitus is a serious public health problem in which a major complication is impaired wound healing. Among the strategies developed to foster tissue repair is the use of medicinal plants. The bark of Stryphnodendron adstringens, which is popularly used as an aid in wound healing, has a documented effect on wound repair in normal rats. This study evaluated the healing action of the crude extract of S. adstringens in diabetic rats, and its chemical content. Compounds present in the crude extract were characterized by mass spectrometry. In diabetic rats (streptozotocin 35 mg/kg), two wounds made in the skin were treated daily for 4, 7, 10, and 14 days with gel containing 1 % crude extract or with base gel. Histological analyses involved the measurement of the length and thickness of the re-epithelialized surface, quantification of the number of cells in mitosis, and types I and III collagen fibers. Also, cutaneous permeation by photoacoustic spectroscopy, and the expression of cyclooxygenase-2 and vascular endothelial growth factor by Western blot were assessed. The crude extract fingerprint showed masses indicating proanthocyanidins. The crude extract mainly stimulated cell migration and proliferation of keratinocytes at the beginning of the treatment in addition to stimulating the replacement of type III collagen fibers by type I collagen fibers at 10 and 14 days. The photoacoustic spectroscopy technique showed that the gel containing 1 % of crude extract permeated through the skin to the dermis, where the crude extract was found. Vascular endothelial growth factor was stimulated after 7 days of treatment with the crude extract and cyclooxygenase-2 at 4, 7, and 10 days. The crude extract of S. adstringens acted in tissue repair in wounds in diabetic rats by stimulating the production of collagen fibers at the wound site. The crude extract favored the formation of a more organized extracellular matrix and filled the entire extent of the wound, and also fostered the upregulation of cyclooxygenase-2 and vascular endothelial growth factor, which are essential to this process. These crude extract actions in diabetic wounds are probably due to the presence of proanthocyanidins.

Morphological and Structural Changes in Lung Tissue Infected by Paracoccidioides brasiliensis: FTIR Photoacoustic Spectroscopy and Histological Analysis

This study evaluated physical, chemical and morphological changes in lungs of mice infected with Paracoccidioides brasiliensis. The animals were inoculated with 0.1 mL of fungal suspension of the P. brasiliensis 18 isolate and were euthanized 1, 2, 4 and 8 weeks after inoculation. The upper left lobe of the lung was isolated, fixed and processed for paraffin embedding. The sections were stained with H&E for histopathological study, with Gomori‐Grocott to locate and identify the fungus, and with TUNEL immunostaining to detect the occurrence of programmed cell death. The lower and middle right lobes were analyzed by Fourier Transform Infrared Photoacoustic Spectrocopy (FTIR‐PAS) to investigate physical and chemical features of the infected lungs. The results showed that lungs infected by P. brasiliensis underwent structural changes that varied according to the time period analyzed, and that changes in the absorption bands of different chemical groups resulted from these morphological changes. The results suggest that the combination of FTIR‐PAS spectroscopy with morphological evaluation is an effective procedure for the study of paracoccidioidomycosis, one of the most important systemic mycoses that can damage the lung architecture and consequently impair the respiratory function.

Enhanced Cutaneous Wound Healing In Vivo by Standardized Crude Extract of Poincianella pluviosa.

Wound healing is a complex process that involves several biological events, and a delay in this process may cause economic and social problems for the patient. The search continues for new alternative treatments to aid healing, including the use of herbal medicines. Members of the genus Caesalpinia are used in traditional medicine to treat wounds. The related species Poincianella pluviosa (DC.) L.P. Queiroz increases the cell viability of keratinocytes and fibroblasts and stimulates the proliferation of keratinocytes in vitro. The crude extract (CE) from bark of P. pluviosa was evaluated in the wound-healing process in vivo, to validate the traditional use and the in vitro activity. Standardized CE was incorporated into a gel and applied on cutaneous wounds (TCEG) and compared with the formulation without CE (Control) for 4, 7, 10, or 14 days of treatment. The effects of the CE on wound re-epithelialization; cell proliferation; permeation, using photoacoustic spectroscopy (PAS); and proteins, including vascular endothelial growth factor (VEGF), superoxide dismutase 2 (SOD-2) and cyclooxygenase 2 (COX-2) were evaluated. The TCEG stimulated the migration of keratinocytes at day 4 and proliferation on the following days, with a high concentration of cells in metaphase at 7 days. Type I collagen formed more rapidly in the TCEG. PAS showed that the CE had permeated through the skin. TCEG stimulated VEGF at day 4 and SOD-2 and COX-2 at day 7. The results suggest that the CE promoted the regulation of proteins and helped to accelerate the processes involved in healing, promoting early angiogenesis. This led to an increase in the re-epithelialized surface, with significant mitotic activity. Maturation of collagen fibers was also enhanced, which may affect the resistance of the extracellular matrix. PAS indicated a correlation between the rate of diffusion and biological events during the healing process. The CE from P. pluviosa appears promising as an aid in healing.

Characterization of curdlan produced by Agrobacterium sp. IFO 13140 cells immobilized in a loofa sponge matrix, and application of this biopolymer in the development of functional yogurt

BACKGROUND Agrobacterium sp. IFO 13140 cells were immobilized on a loofa sponge and used to produce curdlan over five successive cycles. The interaction between microbial cells and the loofa sponge as well as the produced curdlan were characterized by Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectrometry. The purity of the curdlan was also evaluated. The storage stability of the immobilized cells was assessed and the produced curdlan was used in a functional yogurt formulation. RESULTS The average curdlan production by immobilized cells was 17.84 g L(-1) . The presence of the microorganism in the sponge was confirmed and did not cause alterations in the matrix, and the chemical structure of the curdlan was the same as that of commercial curdlan. The purity of both was similar. The immobilized cells remained active after 300 days of storage at -18 °C. The use of the produced curdlan in a functional yogurt resulted in a product with lower syneresis. CONCLUSION A large number of cells physically adhered to the surface of loofa sponge fibers, and its use as an immobilization matrix to produce curdlan was effective. The use of the produced curdlan in yogurt allowed the development of a more stable product.

Correlation between Histopathological and FT-Raman Spectroscopy Analysis of the Liver of Swiss Mice Infected with Paracoccidioides brasiliensis

Paracoccidioidomycosis is the most important systemic mycosis in Latin America. The main entrance of the fungus is the airway. It primarily occurs in the lung, but in its disseminated form may affect any organ. The liver is one of the organs afflicted by this disease and its homeostasis may be impaired. The aim of the present study was to evaluate the evolution of paracoccidioidomycosis in the liver of Swiss mice and correlate morphological factors with the expression of gp43 and with physicochemical analysis via FT-Raman of the infected organ. According to colony forming unit (CFU) and granuloma counting, the first and second weeks were the periods when infection was most severe. Tissue response was characterized by the development of organized granulomas and widespread infection, with yeasts located within the macrophages and isolated hepatocytes. The gp43 molecule was distributed throughout the hepatic parenchyma, and immunostaining was constant in all observed periods. The main physicochemical changes of the infected liver were observed in the spectral ranges between 1700–1530 cm−1 and 1370 – 1290 cm−1, a peak shifting center attributed to phenylalanine and area variation of -CH2 and -CH3 compounds associated to collagen, respectively. Over time, there was a direct proportional relationship between the number of CFUs, the number of granulomas and the physicochemical changes in the liver of mice infected with Paracoccidioides brasiliensis. The expression of gp43 was similar in all observed periods.

Combination of Histopathology and FT-Raman Spectroscopy for the Study of Experimental Paracoccidioidomycosis in the Spleen

Paracoccidioides brasiliensis (Pb) can disseminate through the lymphatic and hematogenic pathways. As a result the spleen and other lymphoid organs are targets of paracoccidioidomycosis. There are few studies describing this disease in the spleen and more detailed descriptions are required. This study combines Histopathology and Fourier Transform Raman Spectroscopy (FT‐Raman) methods to study spleen infected by Pb. The Swiss mice were euthanized after 1, 2, 4 and 8 weeks of infection with Pb, and their spleens were removed for ex vivo analyzes. Histopathological evaluation revealed that the red pulp was the area most affected, presenting the highest concentration of yeasts, inflammatory cells and cells in apoptosis, with no observation of typical granuloma formation. The main physical–chemical changes were detected in the spectral ranges between 1730–1590 cm−1 and 1390–1280 cm−1 attributed to amide I and vibrational deformation mode of CH3 and CH2 molecules, respectively. The amide I was correlated to total protein content and CH3 and CH2 molecules to collagen of the spleen. The association between histological and physical–chemical methods enabled detection of several alterations in the spleen, including apoptosis, contributing to a better understanding of paracoccidioidomycosis, a tropical neglected disease.