Abstract The environmental and health risks associated with the application of synthetic chemical inputs in agriculture increased the demand for technologies that allow higher performance and quality of vegetable crops by implementing synergistic materials with the principles of sustainability. In this work, the seed coating with the biomass of Dunaliella salina incorporated in a bioplastic film of Manihot esculenta (cassava) was evaluated as an initial growth and secondary compounds stimulator of Coriandrum sativum (coriander) plants. The obtained results demonstrated that the coating stimulated an increase in the germination percentage (28.75%) and also in concentration of bioactive compounds, such as the six-fold increment of caffeic acid (13.33 mg 100 g-1). The carbohydrates, lipids, and proteins present in the microalgae biomass seem to be responsible for these increments once they are known for providing energy to the seedling development and coordinating the secondary metabolites synthesis. As conclusion, we consider the coating with biomass of D. salina an alternative for crop improvement that contributes to the development of sustainable agricultural practices.

To research the potential ability of whole marine sponges to act as biocatalysts, this paper describes for the first time the employment of whole Cliona varians sponge in the stereoselective reduction of prochiral a-keto esters and isatin to the corresponding chiral alcohols. The addition of D-fructose, D-glucose or sucrose remarkably increased the conversion ratios and stereoselectivities by this marine sponge. Furthermore, in the presence of D-glucose and D-maltose, the reduction of isatin by C. varians afforded the corresponding 3-hydroxyindolin-2-one with high conversions (85-90%) and good enantioselectivities (60-74%). These results showed that the marine sponge presents great potential to be used as biocatalyst for stereoselective reduction of carbonyl compounds.

Spondias mombin L. is a Brazilian tree belonging to the family Anacardiaceae and popularly known as “cajá”, the genus is well known by the various exotic fruit species such as “siriguela” (S. purpurea), “umbu” (S. tuberosa) and “umbu-cajá” (S. bahiensis). It presents commercial importance to the locals especially due the small juice fruit industries and the seeds are often discarded as waste after pulping. Despite the regional importance, even today there is little information on the chemical composition of these fruits. Thus, the dichloromethane extract of the waste seeds of S. mombin was subjected to different chromatographic fractionation allowing the isolation of a main triglyceride identified as 1,3-dioleoyl-2-linoleoyl glycerol, two new alkyl phenols named 1-hydroxyl-3-[(Z)-10’-octadecenyl]-benzene and 1-hydroxyl-3-[(Z)-10’-docosenyl] benzene, and a mixture of phytosteroids. The seed’s fatty acid profile and the cytotoxicity of the oils and isolated compounds were also determinated employing BST. The alkenylphenol mixture present some toxicity (CL50 215,4 µg mL-1) in this test.

<p>In this work, an undergraduate organic chemistry experiment based on thermal cracking of glycerin is proposed. The reagent is obtained as a by-product from the practice of biodiesel synthesis, and allows reduction of waste produced in the lab. The main product obtained from thermal cracking was characterized by GC analysis as acrolein. This substance was also identified by chemical derivatization as 2,4-dinitrophenylhydrazone, allowing a combined experiment of identification by synthesis of the derivative.</p>

A redução seletiva do 3-oxoglutarato de dimetila foi realizada em vários níveis. A redução quimiosseletiva da carbonila cetônica com boridreto de sódio é descrita em alto rendimento, fornecendo o 3-hidroxiglutarato de dimetila. Quando o complexo borana-dimetil sulfeto (BMS) foi empregado como agente redutor, um diol ou um triol puderam ser obtidos, respectivamente, a partir do 3-hidróxi- ou do 3-oxoglutarato, permitindo a síntese de compostos 1,3,5-oxigenados prática e eficientemente.

The selective reduction of dimethyl 3-oxoglutarate was accomplished in different levels. A high yielding sodium borohydride reduction of the keto group is fully described leading to dimethyl 3-hydroxyglutarate. When borane-dimethyl sulfide (BMS) complex was used, a diol or a triol compound can be obtained by selective or total reduction of 3-hydroxy- or 3-oxoglutarate, respectively, allowing an efficient and practical route to 1,3,5-oxygenated compounds.

O curso estereoquímico da adição de enolatos de titânio quirais a gama-lactóis derivados do ácido (S)-glutâmico foi investigado. Quando gama-lactóis 5-substituídos foram tratados com enolatos de titânio quirais derivados de N-acetil-, N-propionil-, N-bromoacetil- e N-fenilacetil oxazolidin-2-onas somente dois diastereoisômeros foram obtidos, revelando um completo controle facial pelo enolato de titânio, enquanto que a discriminação facial do íon oxocarbênio mostrou-se dependente da natureza do grupo R³ do enolato. Dessililação com HF/CH3CN aquoso, seguida de redução com LiBH4, forneceu eficientemente dióis tetraidrofurânicos trans-2,5-dissubstituídos e recuperação do auxiliar quiral.

The sterochemical outcome of the addition of chiral titanium enolates to gamma-lactols derived from (S)-glutamic acid were examined. When 5-substituted gamma-lactols were treated with chiral titanium enolates of N-acetyl-, N-propionyl-, N-bromoacetyl- and N-phenylacetyl oxazolidin-2-ones, only two diastereoisomers were obtained, revealing complete facial control by the chiral titanium enolate while the oxocarbenium ion facial discrimination was dependent on the nature of the enolate R³ substituent. After desilylation with aqueous HF/CH3CN, LiBH4 reduction allowed the efficient preparation of the corresponding trans-2,5-disubstituted tetrahydrofuran diols and recovery of the chiral auxiliary.

A forma natural do (+)-sitofilure, feromônio de agregação de Sitophilus oryzae L. e Sitophilus zeamais M., foi preparada em 12 etapas, 18% de rendimento total e 82% de excesso enantiomérico a partir da redução microbiológica de 3-oxopentanoato de metila com S. cerevisiae na presença de cloroacetato de etila.

The asymmetric synthesis of (+)-sitophilure, the aggregation pheromone of Sitophilus oryzae L. and Sitophilus zeamais M., was carried out in 12 steps, 18% overall yield and 82% enantiomeric excess from the enzymatic reduction of methyl 3-oxopentanoate with S. cerevisiae in the presence of ethyl chloroacetate.

A síntese quimioenzimática da forma enantiomericamente enriquecida (80% ee) da (-)-serricornina (1), feromônio sexual da praga do fumo Lasioderma serricorne F., foi alcançada em 8 etapas e 13% de rendimento total a partir de (R)-3-hidroxipentanoato de metila, obtido da redução de 3-oxopentanoato de metila com fermento de padaria (S. cerevisiae) na presença de álcool alílico como inibidor enzimático.

A short and efficient preparation of enantiomerically enriched (80% ee) (-)-serricornine (1), the sex pheromone of the cigarette beetle Lasioderma serricorne F., was developed in 8 steps and 13% overall yield from methyl (R)-3-hydroxypentanoate readily prepared by baker's yeast reduction of methyl 3-oxopentanoate in the presence of allyl alcohol as enzyme inhibitor.