Immobilization and application of the recombinant xylanase GH10 of Malbranchea pulchella in the production of xylooligosaccharides from hydrothermal liquor of the eucalyptus (Eucalyptus grandis) wood chips

Xylooligosaccharides (XOS) are widely used in the food industry as prebiotic components. XOS with high purity are required for practical prebiotic function and other biological benefits, such as antioxidant and inflammatory properties. In this work, we immobilized the recombinant endo-1,4-β-xylanase of Malbranchea pulchella (MpXyn10) in various chemical supports and evaluated its potential to produce xylooligosaccharides (XOS) from hydrothermal liquor of eucalyptus wood chips. Values >90% of immobilization yields were achieved from amino-activated supports for 120 min. The highest recovery values were found on Purolite (142%) and MANAE-MpXyn10 (137%) derivatives, which maintained more than 90% residual activity for 24 h at 70 °C, while the free-MpXyn10 maintained only 11%. In addition, active MpXyn10 derivatives were stable in the range of pH 4.0–6.0 and the presence of the furfural and HMF compounds. MpXyn10 derivatives were tested to produce XOS from xylan of various sources. Maximum values were observed for birchwood xylan at 8.6 mg mL−1 and wheat arabinoxylan at 8.9 mg mL−1, using Purolite-MpXyn10. Its derivative was also successfully applied in the hydrolysis of soluble xylan present in hydrothermal liquor, with 0.9 mg mL−1 of XOS after 3 h at 50 °C. This derivative maintained more than 80% XOS yield after six cycles of the assay. The results obtained provide a basis for the application of immobilized MpXyn10 to produce XOS with high purity and other high-value-added products in the lignocellulosic biorefinery field.The authors gratefully acknowledge FAPESP (São Paulo Research Foundation, grants No: 2018/07522-6) and FCT (POCI-01-0145-FEDER-032206)—transnational cooperation project EcoTech, and National Institute of Science and Technology of Bioethanol, INCT, CNPq 465319/2014-9/FAPESP n ◦ 2014/50884- 5) for financial support. Research scholarships were granted to RCA, DA, and JCSS by FAPESP (Grant No: 2020/00081-4, 2020/15510-8, and 2019/21989-7, respectively), to CCVD and VEP by CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Finance Code 001).info:eu-repo/semantics/publishedVersio

Histoquímica e morfometria da placenta de ratas tratadas com dexametasona

A dexametasona, um glicocorticóide sintético, tem a capacidade de atravessar a placenta aumentando o nível de circulação de corticosteróides da mãe para o feto durante a prenhez. Quando administrada nas fases finais da prenhez pode produzir efeitos indesejáveis na formação da placenta e em vários órgãos da prole. Assim, o presente estudo objetivou investigar o efeito da administração da dexametasona (0,8mg/dia/animal) nos cinco primeiros dias da prenhez, sobre o desenvolvimento placentário de ratas. Utilizou-se 30 ratas albinas, divididas em dois grupos: Grupo I -ratas prenhes sem aplicação de dexametasona, sacrificadas ao 7º e 14º dia; Grupo II -ratas submetidas à aplicação de dexametasona nos cinco primeiros dias de prenhez, sacrificadas ao 7º e 14º dia. Os resultados mostraram que a dexametasona não afetou o número e a histologia dos sítios de implantação, porém, promoveu alteração no disco placentário ocasionando hipertrofia na camada de células trofoblásticas gigantes. Não foram evidenciadas alterações no teor de colágeno, porém houve interferência no metabolismo do glicogênio no espongiotrofoblasto trofospongio. Na morfometria de linhas houve diferença entre os grupos na região de labirinto e células trofoblásticas gigantes, porém a morfometria de pontos só ratificou as alterações percebidas na região do labirinto

Effect of irradiation (γ-rays) on the physical, sensory and nutritive properties of bean seeds

Grãos de feijão (Phaseolus vulgaris, L. cv. Carioca 80) com um ano de estocagem em câmara seca (12°C, 50% UR) foram submetidos a irradiação gama (500 e 1.000 krad). Comparado com o feijão não-irradiado, a irradiação com 500 krad aumentou a veloci­dade e a capacidade de hidratação dos grãos, reduziu o tempo de cocção a 1/3, havendo, en­tretanto, uma diminuição da qualidade sensorial em relação ao aparecimento de odor estranho e diminuição do odor típico de feijão cozido. A dureza dos grãos irradiados foi menor aos 10 e 20 min. de cocção em panela de pressão, não diferindo da dos não-irradiados aos 30 min. de cocção. Não foram detectadas diferenças entre os dois níveis de irradiação. A irradiação com 1.000 krad não afetou o quociente de eficiência protéica, porém diminuiu a digestibilidade, o valor biológico e a utilização líquida da proteína. Quando a metionina foi adicionada à dieta (2% da proteína), o efeito negativo da irradiação foi eliminado. A ingestão de dieta e o ganho de peso foram maiores para os ratos que receberam feijão irradiado suplementado com me­tionina, comparado com o não-irradiado também suplementado.Dry beans (Phaseolus vulgaris L. cv. Carioca 80) which had been stored for one year at 12°C one year at 12°C and 50% RH were submitted to gamma irradiation (500 and 1000 krad). Compared to nonirradiated bean, irradiation with 500 krad increased hydration capacity and velocity and reduced the cooking time to 1/3. A decrease in natural cooked bean odor and appearence of off-odor, was noticed. The hardness of irradiated beans was significantly lower than nonirradiated at 10 and 20 min of cooking in pressure cooker. There was no difference between the two after 30 min cooking. No differences were detected between the two levels of irradiation. Irradiation with 1000 krad did not affect the protein efficiency ratio but it did affect negatively the digestibility, the biological value and the net protein utilization. When methionine was added (2% of the protein) to the diet, the negative effects of irradiation were eliminated. Diet consumption and body weight gain improved for the rats fed on diet containing irradiated beans supplemented with methionine, when compared with rats fed the diet containing nonirradiated beans equally supplemented with methionine

Neonatal treatment with naloxone increases the population of Sertoli cells and sperm production in adult rats

Endogenous opioid peptides play an important role in the ontogenesis of the functional and morphological parameters of the seminiferous epithelium. The aim of this study was to evaluate the effects of neonatal manipulations with naloxone, an opioid antagonist, on the population of Sertoli cells and on sperm production in adult rats. Rats were assigned to receive 8 $\mu$g per gram of body weight twice a day with interval of 8 h of naloxone and they were compared to a control group receiving saline. Naloxone groups presented the following findings when compared to the control group: increased body weight from the 2nd to the 27th day; a smaller seminiferous epithelium height, smaller seminiferous tubule diameter, increased number of Sertoli cells and daily sperm production per testis, increased daily sperm production per gram per testis and increased total length of the seminiferous tubule of the treated groups. According to our study, the neonatal treatment with naloxone during the critical period of testis development was able to change the proliferative dynamics of Sertoli cells by an intra and/or extra testicular blockage of opioid receptors, confirming the direct relation between the number of Sertoli cells and the number of spermatozoids

Ectopic testis in coati (Nasua nasua Linnaeus, 1766)

ABSTRACT: This paper reports a case of unilateral extracorporeal ectopic testes in a captive coati (Nasua nasua) in the State Park of Dois Irmãos Zoo, Recife/PE, Brazil. The testicle was located in the subcutaneous tissue of the inguinal region not adhered to the surrounding tissues. After bilateral orchiectomy, both testes were measured, fixed with 10% formalin buffered and embedded in paraffin for histopathological evaluation. The left testis measured 1.2 cm width by 1.7cm length, and the right one measured 1.5 cm width by 2.0 cm length. The ectopic testes had seminiferous epithelium without post-meiotic germ cell lines. The non-ectopic testis had several changes in the seminiferous epithelium that indicated degeneration. In both epididymis, the lumen did not contain sperm and the major epithelial structural alterations were more distinct in the epididymis associated to the ectopic testicle. In conclusion, the ectopic testis and epididymis had lesions compatible with testicular exposition to body temperature. Non-ectopic epididymis and testis had minor lesions but could be related to the infertility of the coati