Effects of glycosidases and GSH pretreatments, fermentation temperatures, and aging time on the physicochemical, organic acids, and aroma profiles of perry.

The lack of sufficient flavour in perry represents a barrier to its further industrialization. This study aimed to investigate the effects of glutathione (GSH), β-glucosidase (Glu), and α-L-rhamnosidase (Rha) pretreatments, the fermentation temperature from 16 °C to 28 °C, and the aging time of 1, 2, and 3 years (PA1, PA2, and PA3) on the physicochemical properties, organic acids, and aroma profiles were investigated. The results demonstrated that the synergistic effect of Glu, Rha, and GSH was more effective than their individual or paired applications in enhancing the varietal aromas.

Enantioselective Synthesis of 3-Hydroxy-2-Oxindoles via Ni-Catalyzed Asymmetric Addition of Aromatic Bromides to α-Ketoamides.

Nickel-catalyzed asymmetric intramolecular addition of aryl halides to α-ketoamides has been achieved to afford chiral 3-substituted-3-hydroxy-2-oxindoles in excellent yields and high enantioselectivities (up to 99 % yield and 98 % ee), which provides efficient access to valuable molecules containing 3-hydroxy-2-oxindole core. The gram-scale reaction proved the potential utility of the methodology.

Applications of Ene-Reductases in the Synthesis of Flavors and Fragrances.

Flavors and fragrances (F&F) are interesting organic compounds in chemistry. These compounds are widely used in the food, cosmetic, and medical industries. Enzymatic synthesis exhibits several advantages over natural extraction and chemical preparation, including a high yield, stable quality, mildness, and environmental friendliness.

Theoretical Analysis of Selectivity Differences in Ketoreductases toward Aldehyde and Ketone Carbonyl Groups.

alcohol dehydrogenase (ADH) and ketoreductase from . CA49 (KRED12) exhibit different chemoselectivity and stereoselectivity toward a substrate with both keto and aldehyde carbonyl groups. ADH selectively reduces the keto carbonyl group while retaining the aldehyde carbonyl group, producing optically pure -alcohols.

Chitosan derived efficient and stable Pd nano-catalyst for high efficiency hydrogenation.

The design and development of green and efficient supported catalysts is the frontier direction in the field of green synthesis, which conforms to the strategic concept of green sustainable chemistry and "carbon neutrality". Herein, we used a renewable resource chitosan (CS) derived from seafood wastes of chitin as carriers to design two different chitosan-supported palladium (Pd) nano-catalysts through different activation methods. The Pd particles were firmly and uniformly dispersed on the chitosan microspheres due to the interconnected nanoporous structure and functional groups of chitosan, proved by diverse characterizations.

Iridium-catalyzed chemoselective asymmetric hydrogenation of conjugated enones with ferrocene-based multidentate phosphine ligands.

A series of novel and readily prepared ferrocene-based multidentate phosphine ligands (f-PNNO) have been developed and successfully used in iridium-catalyzed enantioselective 1,2-reduction of α,β-unsaturated ketones, delivering chiral allylic alcohols in high yields and high enantioselectivities (up to 99% yield and up to 99% ee). Furthermore, the gram scale reaction proceeded very smoothly with 0.001 mol% catalyst loading, which indicated that the newly developed Ir/f-PNNO catalytic system has excellent activity in asymmetric hydrogenation of conjugated enones.

Ir/f-Ampha complex catalyzed asymmetric sequential hydrogenation of enones: a general access to chiral alcohols with two contiguous chiral centers.

A general and highly efficient method for asymmetric sequential hydrogenation of α,β-unsaturated ketones has been developed by using an iridium/f-Ampha complex as the catalyst, furnishing corresponding chiral alcohols with two contiguous stereocenters in high yields with excellent diastereo- and enantioselectivities (up to 99% yield, >20 : 1 dr and >99% ee). Control experiments indicated that the C[double bond, length as m-dash]C and C[double bond, length as m-dash]O bonds of the enones were hydrogenated sequentially, and the final stereoselectivities were determined by the dynamic kinetic resolution of ketones. Moreover, DFT calculations revealed that an outer sphere pathway was involved in both reduction of C[double bond, length as m-dash]C and C[double bond, length as m-dash]O bonds of enones.

Chitin microsphere supported Pd nanoparticles as an efficient and recoverable catalyst for CO oxidation and Heck coupling reaction.

Chitin derived from seafood wastes is a sustainable biopolymer, which can be used to constructe new materials to reduce the environmental pollution caused by non-biodegradable plastics. Herein, nanofibrous microspheres fabricated from chitin solution were used as carriers to construct three different chitin-supported Pd catalysts through diverse activation methods, subsequently revealed their differences in structure and performance. The palladium nanoparticles were firmly and highly dispersed on the microspheres due to the interconnected nanofibrous networks and functional groups of chitin, confirmed by various physicochemical characterizations.

Nickel-Catalyzed Asymmetric Addition of Aromatic Halides to Ketones: Highly Enantioselective Synthesis of Chiral 2,3-Dihydrobenzofurans Containing a Tertiary Alcohol.

A highly enantioselective and straightforward synthetic procedure to chiral 3-hydroxy-2,3-dihydrobenzofurans has been developed by nickel/bisoxazoline-catalyzed intramolecular asymmetric addition of aryl halides to unactivated ketones, giving 2,3-dihydrobenzofurans with a chiral tertiary alcohol at the C-3 position in good yields and excellent enantioselectivities (up to 92% yield and 98% ee). The gram-scale reaction also proceeded smoothly without a loss of yield and enantioselectivity.

[Studies of relationship between infection of HPV, synergistic factors and cervical carcinoma].

The carcinogenesis of the human cervical precancerous lesion,cervical carcinoma is known closely associated with human papillomavirus (HPV). The purpose of this article is to identify whether HSV and CMV play as co-factor role in the carcinogenesis. Eighty-one cases of various cervical lesions were analyzed by HPV6/11, HPV16/18 in situ hybridization.

[Rapid detection of three common deletional alpha thalassemias in Chinese by single-tube multiplex PCR].

Objective: To develop a simple, rapid, accurate, and cost-effective single-0tube multiplex polymerase chain reaction (PCR) assay, which could be used for molecular screening and prenatal diagnosis, for detection of three commonest deletional alpha-thalassemias (-- (SEA), -alpha (3.7) and -alpha (4.2)) in Chinese population.

[Clinical phenotype genotype correlation in children with hemoglobin H disease in Zhuhai area of China].

Objective: Alpha-thalassemia is one of the most common monogene disorders in the world. Most frequently, it is caused by deletions of alpha-globin gene (-alpha or --), and less commonly resulted from the non-deletional mutation (alpha(T)alpha). Hemoglobin H (HbH) disease is the most severe type among survivors of alpha-thalassemia.

Evaluation of clinical application of gap-PCR as a routine method for alpha-thalassemia carrier detection.

Objective: To evaluate the feasibility of using gap-PCR for routine screening of alpha-thalassemia in clinical laboratory.

Methods: A total of 382 clinical blood samples randomly collected from the population of Zhuhai city were screened for alpha-thalassemia determinants with hematological and gap-PCR method respectively in a double-blind manner. Parallel analysis with Southern blotting was performed to verify the genotyping results by PCR.