One new phenylpropanoid from Hainan Ceriops tagal / 中草药

Objective: To study the chemical constituents from the ethyl acetate fraction of Ceriops tagal. Methods: Compounds were isolated and purified by various column chromatography, recrystallization, and HPLC. And their structures were elucidated by physicochemical property and spectral analysis. Results: Eight compounds were isolated from the ethyl acetate fraction of Ceriops tagal and identified as (E)-methyl-3-(5-hydroxy-2,3,4-trimethoxyphenyl)acrylate (1), tagalphenylpropinoidin A (2), coniferyl aldehyde (3), 2,3-dimethoxy-5-(1-propenyl)phenol (4), methyl syringate (5), syringaldehyde (6), pinosylvin monomethyl ether (7), and n-hexadecane acid (8), respectively. Conclusion: Compound 1 is a new phenylpropanoid, named as tagalphenylpropanoidin C, and compounds 4-8 are obtained from C. tagal for the first time.

Transcriptional profiling of genes involved in n-hexadecane compounds assimilation in the hydrocarbon degrading Dietzia cinnamea P4 strain

The petroleum-derived degrading Dietzia cinnamea strain P4 recently had its genome sequenced and annotated. This allowed employing the data on genes that are involved in the degradation of n-alkanes. To examine the physiological behavior of strain P4 in the presence of n-alkanes, the strain was grown under varying conditions of pH and temperature. D. cinnamea P4 was able to grow at pH 7.0-9.0 and at temperatures ranging from 35 ºC to 45 ºC. Experiments of gene expression by real-time quantitative RT-PCR throughout the complete growth cycle clearly indicated the induction of the regulatory gene alkU (TetR family) during early growth. During the logarithmic phase, a large increase in transcriptional levels of a lipid transporter gene was noted. Also, the expression of a gene that encodes the protein fused rubredoxin-alkane monooxygenase was enhanced. Both genes are probably under the influence of the AlkU regulator.

Hydrophobicity test in mutans Streptococci

Kinetic hydrophobic measurements were performed by confronting 40 mutans streptococci from thirty 10- to 20-year-old patients with 200 ml hexadecane (Sigma). Fourteen patients had high dental caries risk (Group A), dmft + DMFT >5 with 3 or more active caries, and 16 had low dental caries risk (Group B), dmft + DMFT <3 without active caries. Twenty bacteria from Group A and 20 bacteria from Group B were typed using De La Higuera's procedure and confirmed by API strip (bio- Merieux). From the 14 patients in Group A we obtained 12 S. mutans (8 hydrophobic/ 4 non-hydrophobic), 5 S. sobrinus (4 hydrophobic/ 1 non-hydrophobic) and 3 S. rattus (hydrophobic). From the 16 patients in Group B we obtained 11 Streptococcus mutans (10 non-hydrophobic/ 1 hydrophobic), 7 Streptococcus sobrinus (6 non-hydrophobic/ 1 hydrophobic) and 2 Streptococcus rattus (hydrophobic). Patients with high dental caries risk have a higher prevalence of hydrophobic bacteria than patients with low dental caries risk (p=0.0003). All typed S. rattus were hydrophobic.

Con el objeto de evaluar una posible relacion entre hidrofobicidad y caries dental, se estudiaron 40 cepas de Streptococcus grupo mutans provenientes de 30 pacientes de entre 10 y 20 anos, 14 pacientes con tres o mas caries activas e indice ceod mas CPOD > 5 (Grupo A) y 16 pacientes sin caries activas, con ceod mas CPOD < 3 (Grupo B). Las cepas fueron aisladas a partir de muestras de saliva en AMS-BT y tipificadas por pruebas bioquimicas y API-strep realizandose la medicion cinetica de hidrofobicidad, enfrentandolas con 200 ml de hexadecano (Sigma). En el grupo A se caracterizaron 12 cepas Streptococcus mutans: 8 hidrofobicas y 4 no hidrofobicas, 5 cepas de Streptococcus sobrinus: 4 hidrofobicas y 1 no hidrofobica y 3 cepas Streptococcus rattus hidrofobicas. En el grupo B, se caracterizaron 11 cepas de S. mutans, 10 no hidrofobicas y 1 hidrofobica, 7 cepas de S. sobrinus: 6 no hidrofobicas y 1 hidrofobica y 2 cepas de S. rattus hidrofobicas. Todos los pacientes del grupo A presentaron al menos 1 cepa hidrofobica. En las cepas aisladas de estos pacientes se demostro la existencia de una alta prevalencia de Streptococcus grupo mutans con caracteristicas hidrofobicas p=0,0003. Estos resultados indicarian la relacion entre la capacidad de adherencia a hexadecano y caries activa. Todas las cepas tipificadas como S. rattus fueron hidrofobicas independientemente del grupo de origen.