Faveleira (Cnidoscolus quercifolius Pohl) seed press cake flour: production, characterization and application for use in cookies.

BACKGROUND: Food processing produces large volumes of waste that can be transformed into useful and relevant ingredients. The by-product of oil extraction from faveleira seeds is a potentially low-cost raw material that can be used for obtaining functional foods. This study aimed to analyze the physicochemical properties, chemical composition, and antioxidant activity of faveleira (Cnidoscolus quercifolius Pohl) seed press cake flour (FSPCF). Additionally, the chemical composition, antioxidant activity, and physical, microbiological, and sensory aspects of cookies with 0, 25%, or 50% substitution of refined wheat flour (RWF) with FSPCF (0-FSPCF, 25-FSPCF, and 50-FSPCF cookies, respectively) were evaluated. RESULTS: FSPCF exhibited good physicochemical properties, high antioxidant activity (0.45 ± 0.00 and 42.83 ± 1.30 g TE g-1 for the DPPH and ABTS methods, respectively), and high polyphenol content (particularly gallic acid at 21015.85 ± 4981.76 g kg-1 ) and is also rich in minerals and fiber (359.40 ± 1.10 g kg-1 ). Replacement of RWF with FSPCF increased the activity of antioxidants and the levels of polyphenols, ash, lipids, proteins, and fibers. The 50-FSPCF cookie possessed the highest linoleic acid content (97.50 ± 8.47 g kg-1 ). Flour replacement influenced the weight of the cookies without affecting the other physical characteristics. The cookies yielded good sensory acceptance and purchase intentions. Contamination was not detected. CONCLUSION: Faveleira flour possesses high nutritional and bioactive value and can be used as a functional ingredient in cookies and possibly in other bakery products such as bread, cakes, and pastas. © 2022 Society of Chemical Industry.

Ultrasound pretreatment application in dehydration: its influence on the microstructure, antioxidant activity and carotenoid retention of biofortified Beauregard sweet potato (Ipomoea batatas Lam).

This work aimed to evaluate the effects of ultrasound pretreatment on the microstructure, antioxidant activity, and carotenoid retention of biofortified Beauregard sweet potato (BBSP). The pretreatment was carried out in an ultrasonic bath at 30 °C for 10 min, and it was evaluated in terms of water loss and solid gain. The drying process was performed at two different temperatures (50 and 70 °C). Six different semi-theoretical mathematical models were examined to characterize the drying curves, and quality analyses were executed. The two-terms exponential model provided the best simulation of the drying curves. Drying time was reduced by performing ultrasound pretreatment and by increasing drying temperature. The ultrasound treatment caused greater agglomeration, breakage, or strangulation of the BBSP structure, increasing porosity, and thus increasing drying rates. Drying caused a diminution of total carotenoids content and influenced antioxidant activity. However, the samples pretreated with ultrasound and dried produced lower total carotenoids loss.

Reutilization of residual glycerin for the produce ß-carotene by Rhodotorula minuta.

This study aimed to evaluate the production of carotenoid pigments by Rhodotorula spp. in submerged fermentation, using residual glycerin from biodiesel production as a carbon source. Chromatographic analysis by HPLC showed that the residual glycerin used as substrate was 57.88% composed of glycerol. The best growth conditions were found in the fermentation medium composed of residual glycerin at a concentration of 30 g/L and pH 9. From all the Rhodotorula strains tested, R. minuta URM6693 was selected because of their performance and adaptation in all culture media assayed. The maximum volumetric production of carotenoids was found at 48 h (equivalent to 17.20 mg/L, for the R. minuta). The production of ß-carotene since the first 24 h of fermentation reach a final concentration of 1.021 mg/L. The yeast Rhodotorula minuta proved its capability to efficiently convert the substrate (mainly at the concentration of 50 g/L), obtaining products of biotechnological interest.

Effects of Dietary Brazilian Palm Oil (Mauritia flexuosa L.) on Cholesterol Profile and Vitamin A and E Status of Rats.

In vitro studies have been carried out to establish the nutritional differences between crude and refined vegetable oils; however, the impact of the consumption of these foods on metabolism, in particular the effect of buriti oil, needs to be further evaluated. The aim of this study was to evaluate the biochemical and murine parameters and the vitamin A and E status in young rats fed with diets supplemented with crude or refined buriti oil. The animals (n = 30) were randomized into three groups receiving diet added of soybean oil (control), crude buriti oil (CBO) and refined buriti oil (RBO) for 28 days. Rats fed with diet added of refined buriti oil (RBO) showed reduced total cholesterol (up to 60.27%), LDL (64.75%), triglycerides (55.47%) and enzyme aspartate transaminase (21.57%) compared to those fed with diet added of crude oil. Serum and hepatic retinol and tocopherol were higher by two to three times in CBO and RBO groups compared to the control group, but no differences were observed for murine parameters. The results indicate that buriti oil is an important source of the antioxidant vitamins A and E, and refined buriti oil is suggested as alternative to improve the lipid profile of healthy rats.

Effects of post-harvest treatment using chitosan from Mucor circinelloides on fungal pathogenicity and quality of table grapes during storage.

The aim of this study was to extract chitosan (CHI) from Mucor circinelloides UCP 050 grown in a corn steep liquor (CSL)-based medium under optimized conditions and to assess the efficacy of the obtained CHI to inhibit the post-harvest pathogenic fungi Aspergillus niger URM 5162 and Rhizopus stolonifer URM 3482 in laboratory media and as a coating on table grapes (Vitis labrusca L.). The effect of CHI coating on some physical, physicochemical and sensory characteristics of the fruits during storage was assessed. The greatest amount of CHI was extracted from M. circinelloides UCP 050 grown in medium containing 7 g of CSL per 100 mL at pH 5.5 with rotation at 180 rpm. CHI from M. circinelloides UCP 050 caused morphological changes in the spores of the fungal strains tested and inhibited mycelial growth and spore germination. CHI coating delayed the growth of the assayed fungal strains in artificially infected grapes, as well as autochthonous mycoflora during storage. CHI coating preserved the quality of grapes during storage, as measured by their physical, physicochemical and sensory attributes. These results demonstrate that edible coatings derived from M. circinelloides CHI could be a useful alternative for controlling pathogenic fungi and maintaining the post-harvest quality of table grapes.

Green conversion of agroindustrial wastes into chitin and chitosan by Rhizopus arrhizus and Cunninghamella elegans strains.

This article sets out a method for producing chitin and chitosan by Cunninghamella elegans and Rhizopus arrhizus strains using a green metabolic conversion of agroindustrial wastes (corn steep liquor and molasses). The physicochemical characteristics of the biopolymers and antimicrobial activity are described. Chitin and chitosan were extracted by alkali-acid treatment, and characterized by infrared spectroscopy, viscosity and X-ray diffraction. The effectiveness of chitosan from C. elegans and R. arrhizus in inhibiting the growth of Listeria monocytogenes, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella enterica, Escherichia coli and Yersinia enterocolitica were evaluated by determining the minimum inhibitory concentrations (MIC) and the minimum bactericidal concentrations (MBC). The highest production of biomass (24.60 g/L), chitin (83.20 mg/g) and chitosan (49.31 mg/g) was obtained by R. arrhizus. Chitin and chitosan from both fungi showed a similar degree of deacetylation, respectively of 25% and 82%, crystallinity indices of 33.80% and 32.80% for chitin, and 20.30% and 17.80% for chitosan. Both chitin and chitosan presented similar viscosimetry of 3.79-3.40 cP and low molecular weight of 5.08×10³ and 4.68×10³ g/mol. They both showed identical MIC and MBC for all bacteria assayed. These results suggest that: agricultural wastes can be produced in an environmentally friendly way; chitin and chitosan can be produced economically; and that chitosan has antimicrobial potential against pathogenic bacteria.

Effect of corn steep liquor (CSL) and cassava wastewater (CW) on chitin and chitosan production by Cunninghamella elegans and their physicochemical characteristics and cytotoxicity.

Microbiological processes were used for chitin and chitosan production with Cunninghamella elegans UCP/WFCC 0542 grown in different concentrations of two agro-industrial wastes, corn steep liquor (CSL) and cassava wastewater (CW) established using a 2² full factorial design. The polysaccharides were extracted by alkali-acid treatment and characterized by infrared spectroscopy, viscosity, thermal analysis, elemental analysis, scanning electron microscopy and X-ray diffraction. The cytotoxicity of chitosan was evaluated for signs of vascular change on the chorioallantoic membrane of chicken eggs. The highest biomass (9.93 g/L) was obtained in trial 3 (5% CW, 8% CSL), the greatest chitin and chitosan yields were 89.39 mg/g and 57.82 mg/g, respectively, and both were obtained in trial 2 (10% CW, 4% CSL). Chitin and chitosan showed a degree of deacetylation of 40.98% and 88.24%, and a crystalline index of 35.80% and 23.82%, respectively, and chitosan showed low molecular weight (LMW 5.2 × 10³ Da). Chitin and chitosan can be considered non-irritating, due to the fact they do not promote vascular change. It was demonstrated that CSL and CW are effective renewable agroindustrial alternative substrates for the production of chitin and chitosan.

Development and Evaluation of Nutritional and Quality Standard of Beef Burger Supplemented with Pumpkin (Cucurbita moschata) Seed Flour.

The composition of pumpkin seeds includes bioactive compounds, proteins, polyunsaturated fatty acids, and dietary fibers. Thus, the objective of this research was to develop and evaluate the nutritional and quality standard of beef burgers supplemented with pumpkin seeds (Cucurbita moschata) added in different proportions. To process the pumpkin seed flour (PSF), the seeds were sanitized, dried in an oven, crushed, and sieved. Through such means, three formulations of beef burgers were prepared, named S (without the addition of PSF), F5 (with the addition of 5% (w/w) of PSF), and F10 (with the addition of 10% (w/w) of PSF). The respective results for burgers P, F5, and F10 were as follows (w/w): proteins 17.61%, 18.04%, 19.86%; lipids 12.19%, 12.42%, 14.55%; ash 1.77%, 1.86%, 1.94%; fibers 0%, 0.88%, 1.76%; phenolic compounds 39.55, 82.93, 90.30 (mg/g); and total antioxidant capacity 11.09%, 18.48%, 24.45%. Regarding the sensory analysis attributes, tasters gave sample F10 scores lower than 7. However, the standard and F5 samples showed results higher than 7 for all parameters. For the determination of shelf life, an expiration date of 30 days was established. It was observed that adding PSF to industrialized products adds nutritional value with the inclusion of polyunsaturated fats, phenolic compounds, and dietary fibers.

Development of Edible Coatings Based on Pineapple Peel (Ananas Comosus L.) and Yam Starch (Dioscorea alata) for Application in Acerola (Malpighia emarginata DC).

Acerola fruit has great nutritional and economic relevance; however, its rapid degradation hinders commercialization. The use of coatings reduces post-harvest biochemical modifications and provides physical and biological protection for vegetables such as acerola. This study developed and characterized an edible coating made from pearl pineapple peel flour (PPPF) and yam starch (YS) to preserve the quality standards of acerola fruits during storage at room temperature and under refrigeration. The edible coating, composed of 4 g of PPPF, 3 g of starch, and 10% glycerol, presented excellent moisture content (11%), light tone (L* 83.68), and opacity (45%), resistance to traction of 27.77 Mpa, elastic modulus of 1.38 Mpa, and elongation percentage of 20%. The total phenolic content of the coating was 278.68 ± 0.45 mg GAE/g and the antioxidant activity by DPPH was 28.85 ± 0.27%. The quality parameters of acerolas were evaluated with three treatments: T1-uncoated fruits; T2-fruits coated with 1% glycerol; and T3-fruits coated with PPPF-YS. The T3 treatment reduced the weight loss of stored acerolas, maintaining the light and bright color of the fruits, and delayed the decrease in soluble solids, especially in refrigerated fruits. Therefore, edible coatings based on pineapple flour and yam starch are effective technologies for controlling the physical and physicochemical parameters of acerolas during storage, benefiting the post-harvest quality of this fruit.

Physiological and Technological Properties of Probiotic Lacticaseibacillus rhamnosus GG Encapsulated with Alginate-Chitosan Mixture and Its Incorporation in Whole Milk.

This study developed and evaluated chitosan-sodium alginate capsules containing the probiotic Lacticaseibacillus rhamnosus GG using extrusion and emulsification techniques. The encapsulated L. rhamnosus GG cells were also evaluated for technological and probiotic-related physiological functionalities, as well as when incorporated in UHT and powdered milk. Extrusion (86.01 ± 1.26%) and emulsification (74.43 ± 1.41%) encapsulation techniques showed high encapsulation efficiency and high survival rates of L. rhamnosus GG during 28 days of refrigeration and room temperature storage, especially emulsification capsules (> 81%). The encapsulated L. rhamnosus GG cells showed high survival rates during exposure to simulated gastrointestinal conditions (72.65 ± 1.09-114.15 ± 0.44%). L. rhamnosus GG encapsulated by extrusion and emulsification performed satisfactorily in probiotic-related physiological (pH and bile salts tolerance) and technological properties (positive proteolytic activity, diacetyl and exopolysaccharides production, high NaCl tolerance (> 91%), besides having high heat tolerance (> 76%)). L. rhamnosus GG in extrusion and emulsification capsules had high survival rates (> 89%) and did not significantly affect physicochemical parameters in Ultra-High Temperature (UHT) and powdered milk during storage. The results demonstrate that L. rhamnosus GG can be successfully encapsulated with alginate-chitosan as a protective material through extrusion and emulsification techniques. UHT and powdered milk could serve as appropriate delivery systems to increase the intake of this encapsulated probiotic by consumers.

Efficacy of the application of a coating composed of chitosan and Origanum vulgare L. essential oil to control Rhizopus stolonifer and Aspergillus niger in grapes (Vitis labrusca L.).

This study evaluated the efficacy of the combined application of chitosan (CHI) and Origanum vulgare L. essential oil (OV) in the inhibition of Rhizopus stolonifer URM 3728 and Aspergillus niger URM 5842 on laboratory media and on grapes (Vitis labrusca L.) and its influence on the physical, physicochemical and sensory characteristics of the fruits during storage (25 °C, 12 days and 12 °C, 24 days). The application of mixtures of different CHI and OV concentrations (Minimum Inhibitory Concentration - MIC, 1/2 MIC and 1/4 MIC) inhibited the mycelial growth of the test fungi. The application of CHI and OV at sub-inhibitory concentrations (CHI 1/2 MIC + OV 1/4 MIC; CHI 1/2 MIC + OV 1/2 MIC) inhibited spore germination and caused morphological changes in fungal spores and mycelia, in addition to inhibiting the growth of the assayed fungi strains in artificially infected grapes as well as the autochthonous mycoflora of grapes stored at both room and cold temperature. In general, the application of a coating composed of CHI and OV at sub-inhibitory concentrations preserved the quality of grapes as measured by their physical and physicochemical attributes, while some of their sensory attributes improved throughout the assessed storage time. These results demonstrate the potential of the combination of CHI and OV at sub-inhibitory concentrations to control post-harvest pathogenic fungi in fruits, in particular, R. stolonifer and A. niger in grapes.

Spreadable goat Ricotta cheese added with Lactobacillus acidophilus La-05: Can microencapsulation improve the probiotic survival and the quality parameters?

The impact of the addition of L. acidophilus La-05 (free cells, microencapsulated with alginate [30 g/L] or microencapsulated with alginate coated with chitosan [5 g/L]) on the quality parameters of spreadable goat Ricotta cheese during storage (7 °C/7 days) was evaluated. The addition of probiotic culture resulted in products with lower hardness, gumminess, and springiness, as well as higher cohesiveness and adhesiveness. Furthermore, it increased the yield, and altered the color (higher L*, a* and b* values). The microencapsulation of the probiotic cultures resulted in higher probiotic survival (>6 log CFU/mL in product and simulated gastrointestinal conditions), and improved technological (no moisture loss, lower proteolysis and organic acid content), texture (lower gumminess and adhesiveness), and volatile (compounds with floral and fruity notes and lower "goat" aroma) properties. Chitosan coating did not improve the effects. In conclusion, microencapsulation improved the probiotic survival and the quality parameters of spreadable goat Ricotta cheese.

Chemical and biological activities of faveleira (Cnidoscolus quercifolius Pohl) seed oil for potential health applications.

Faveleira (Cnidoscolus quercifolius) is an emerging Brazilian plant, with seeds rich in edible oil. This study investigates physicochemical properties, chemical composition, thermal and oxidative stability, in vitro and in vivo toxicity, antioxidant, antinociceptive and anti-inflammatory activities of faveleira seed oil. It was observed that the oil has low acidity, value of peroxide, chlorophyll, carotenoids, ß-carotene and high concentrations of unsaturated fatty acids. In addition to presenting thermal and oxidative stability and high total phenolic content, with vanillin, eugenol and quercetin were predominating. The oil showed no toxicity in vitro and in vivo, and presented antioxidant, anti-inflammatory and antinociceptive activities. These findings provide relevant and appropriate conditions for processing of faveleira seed oil as functional food.

Chitosan-citric acid edible coating to control Colletotrichum gloeosporioides and maintain quality parameters of fresh-cut guava.

This study aimed to verify the action of edible chitosan-citric acid (CHI-CA) coating to control Colletotrichum gloeosporioides and maintain quality parameters of fresh-cut guava. Chitosan was obtained from Litopenaeus vannamei shells using high temperature and short exposure times. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of CHI-CA against C. gloeosporioides were determined by macrodilutions at 28 °C/120 h in the absence/presence of CHI-CA (0-10 mg/mL). Scanning electron microscopy was used to evaluate morphological changes in the fungus. Guava slices were coated with CHI-CA (MIC) or 5 mg/mL glycerol (control). Rot incidence and physicochemical, physical, and microbiological factors were determined at 0, 3, 7, and 14 days at 24 °C and 4 °C. Chitosan presented typical structural characterization, 64% deacetylation, and a molecular weight of 1.6 × 104 g/mol. CHI-CA exhibited MIC and MFC values of 5 mg/mL and 10 mg/mL, respectively, and promoted changes in the morphology and cell surface of fungal spores. The fresh-cut guava coated with CHI-CA maintained quality parameters during storage and preserved their sensorial characteristics. Therefore, the use of CHI-CA as a coating is a promising strategy for improving postharvest quality of fresh-cut fruits.

Effects of a New Nano-Silver Fluoride-Containing Dentifrice on Demineralization of Enamel and Streptococcus mutans Adhesion and Acidogenicity.

An experimental dentifrice containing nano-silver fluoride (NSF) and a sodium fluoride (NaF) toothpaste were tested in vitro, against S. mutans, to evaluate the minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC), antiadherence, antiacid, enamel microhardness, and OCT. The microdilution technique was used to determine the MIC and MBC. Fragments of deciduous enamel were treated with dentifrice slurries, containing bacterial suspension and PBS-treated saliva. The quantification of the microorganisms that adhered to the enamel was determined after 24 hours of incubation, and media pH readings were performed after 2 hours and 24 hours. Deciduous teeth were evaluated for microhardness and OCT during 14 days of pH cycling. Data were statistically analyzed using Student's t-test, Mann-Whitney U test, ANOVA, and Tukey tests at 5% of significance. Dentifrices containing NSF presented a lower MIC and higher statistically significant results compared to NaF dentifrices with respect to preventing bacterial adhesion and pH decreases. NSF and NaF dentifrices showed the same ability to avoid enamel demineralization corroborated by the OCT images. The NSF formulation had a better antibacterial effect compared to NaF dentifrices and similar action on the demineralization of enamel indicating their potential effectiveness to prevent caries.

Antimicrobial and cytotoxicity evaluation of colloidal chitosan - silver nanoparticles - fluoride nanocomposites.

The present study aimed to evaluate the antimicrobial activity and cytotoxicity of colloidal chitosan - silver nanoparticle - fluoride nanocomposites (CChAgNpFNc), with different silver nanoparticle shapes and sizes. The syntheses of CChAgNpFNc were performed with silver nitrate added to a chitosan solution, addition of a sodium borohydride solution and solid sodium fluoride. Solution of ascorbic acid was added to synthesize larger silver nanoparticles. CChAgNpFNc obtained: S1- 100% spherical, 8.7±3.1nm; S2- 97% spherical, 15.0±7.9nm and 2.5% triangular, 22.2±9.5nm; S3- 77.3% spherical, 31.8±10.4nm, 15.9% triangular, 27.1±10.1nm and 6.8% elliptical, 33.2±7.8nm; and S4- 75.2% spherical, 43.2±14.3nm; 23.3% triangular 38.2±14.8nm, and 1.5% elliptical 38.4±11.6nm. The CChAgNpFNc showed antimicrobial activity against Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa and Candida albicans, by microdilution technique. The influence on the growth of microorganisms was evaluated using a fluorescence assay, and showed an increasing lag phase and a decreasing log phase. Cytotoxicity was investigated using Artemia salina and MTT assays. The S3 and S4 samples exhibited low cytotoxicity. The S1 and S2 samples inhibited murine macrophages and revealed lethal dose concentrations above 1000mg/mL that were classified as moderately toxic. Thus, CChAgNpFNc are potential options for the control of multiple-drug-resistant microorganisms and do not represent substantial risks to human health.

Effects of chitosan from Cunninghamella elegans on virulence of post-harvest pathogenic fungi in table grapes (Vitis labrusca L.).

This study aimed to obtain chitosan (CHI) from Cunninghamella elegans cultivated in corn step liquid (CSL)-based medium under optimized conditions and to assess the efficacy of the obtained CHI in inhibiting Botrytis cinerea and Penicillium expansum in laboratory media and when applied as a coating on table grapes (Vitis labrusca L.). Moreover, the influence of CHI-based coatings on several physical, physicochemical and sensory characteristics of the fruits during storage was assessed. According to the surface response methodology, the best conditions for isolating CHI from C. elegans cultivated in CSL-medium yielded 8.8 g/100mL at pHs between 5.0 and 5.5 and at 180 rpm. CHI from C. elegans inhibited mycelial growth and spore germination and caused morphological changes in the spores of the tested fungal strains. The CHI coatings delayed the growth of the assayed fungal strains in artificially infected grapes. Applying a CHI coating preserved the quality of grapes, as measured by some physical, physicochemical and sensory attributes, throughout the assessed storage time. These results demonstrate the potential of CHI from C. elegans to control post-harvest pathogenic fungi in fruits, in particular, B. cinerea and P. expansum in table grapes.

Interspecies variation of Kitasatospora recifensis endophytic from yam bean producing thermostable amylases in alternative media.

An endophytic actinomycete isolated from tubers of yam beam (Pachyrhizus erosus L. Urban) was classified as a novel species nominated Kitasatospora recifensis based in phenotypic and genotypic analysis (16S rDNA gene sequence). Monosporic culture using specific ISP2 media revealed three interspecies, which were identified by DNA southern hybridization (Wild strain 13817 W, Aerial Mycelium strain 13817 AM and Vegetative Mycelium strain 13817 VM). The strains were tested for the production of amylolitic enzymes in alternative media. Maximum yields for both enzymes were observed in starch-casein. Higher α-amylase was obtained with strain 13817 W in starch-urea, and amyloglucosidase with strain 13817 AM in starch-ammonium that are economic sources and may be important for industrial purposes. Type strain (DAUFPE 13817(T) = KCTC 9972(T )= DSM 44943(T)).

Estudo Experimental da Ação doFlúor na Prevalência de Cárie / Experimental Study of the Action of Fluoride in Carie Prevention

O presente trabalho teve por objetivo avaliar aprevalência da cárie quando utilizadas dietas hipo ehiperglicídicas. Material e Métodos: Realizou-se umexperimento utilizando-se 36 ratos (Rattus norvegicus albinuswistar), de ambos os sexos, distribuídos em 3 grupos: a)dieta hipoglicídica com água fluoretada (1 ppm); b) dietahiperglicídica mais água fluoretada (1 ppm) e c) dietabalanceada mais água fluoretada. Resultados: Em dentesmolares dos animais analisou-se o grau de prevalência e aprofundidade de penetração das lesões de cárie, em funçãodas dietas. Houve efeito diferenciado das dietas, apresentandomaior grau de prevalência de cárie na seguinteordem: hiperglicídica > balanceada > hipoglicídica. Conclusão:Os resultados sugerem que, a diminuição de sacarose nadieta foi importante para reduzir a prevalência da doença cárie...

The present research had the objective ofevaluating the prevalence of caries in hypoglycemic andhyperglycemic. Materials and Methods: An experiment wascarried out with 36 rats (Rattus norvegicus, albinus Wistar),of both sexes, distributed in three groups: a) hypoglycemicdiet with fluoridate water (1ppm); b) hyperglycemic diet plusfluoridate water (1ppm) and c) balanced diet plus fluoridatewater (1ppm). Results: In the animal’s molar teeth was foundthe prevalence level and penetration depth of caries lesions,caused by the diets. Different effects were experience onthe diets, which showed greater level of prevalence of cariesin the following sequence: hyperglycemic > balanced >hypoglycemic. Conclusion: The results indicate that sucrosedecrease on the diet was important to reduce the cariesdisease...

Growth of Cunninghamella elegans UCP 542 and production of chitin and chitosan using yam bean medium

Microbiological processes were used for chitin and chitosan productions by Cunninghamella elegans (UCP 542) grown in a new economic culture medium. The assay was carried out to evaluate the growth of C. elegans using yam bean (Pachyrhizus erosus L. Urban) medium, in different times of growth (24, 48, 72 and 96 hrs), incubated at 28°C in an orbital shaker at 150 rpm. The lyophilized biomass was determined by gravimetry. The polysaccharides were extracted by alkali-acid treatment, and characterized by infrared spectroscopy, titration and viscosity. C. elegans grown in the yam bean medium and produced higher yields of biomass (24.3 g/ mL) in 96 hrs. The high level was chitosan (66 mg/g), and chitin (440 mg/g) were produced at 48 and 72 hrs of growth, respectively. The polysaccharides showed degree of deacetilation and viscosimetric molecular weight as: 6.2 percent and 3.25 x10(4) g/mol for chitin, and 85 percent and 2.72 x 10(4) g/mol for chitosan, respectively. The results obtained suggest high biotechnological potential of yam bean as an economic source to produce chitin and chitosan by C. elegans. In addition, the new medium using yam bean for production of the chitin and chitosan may be used for many purposes to reduce the cost price of fermentation processes.