Akira Yasunishi

Effects of water and alcohol on the formation of inclusion complexes of d-limonene and cyclodextrins

Abstract Systematic studies have been carried out on the role of water and alcohol in the formation of inclusion complexes between d-limonene and α-, β- and γ-cyclodextrin (CD) by a micro-aqueous method. The inclusion complex was barely formed at zero water content for all CDs. Above the specific water content for each CD, formation of the inclusion complex correlated well with an equation which was derived on the autocatalytic assumption for the inclusion phenomenon. The inclusion complex correlated well with an equation which was derived on the autocatalytic assumption for the inclusion phrnomenon. The minimum water content, which was defined as 1% of the maximum concentration of the inclusion complex formed, coincided with the number of water molecules inside the cavity of the CD. In the presence of ethanol, a significant amount of the inclusion complex was formed for β- and γ-CD/limonene systems, particularly at lower moisture content. However, for α-CD the inclusion fraction decreased significantly i...

Oxidation stability of eicosapentaenoic and docosahexaenoic acid included in cyclodextrins

We have proposed a novel method for complexing of the ω-3 polyunsaturated fatty acids (PUFA), such as eicosapentaenoic and docosahexaenoic acids, with cyclodextrin as dry powders by a twin-screw kneader. The effect of various oxidation conditions on powdery PUFA were investigated. Further, the powdery PUFA developed was employed in the preparation of fish meal as a functional sea food paste.

A Short-Cut Method for Estimating l -Menthol Retention Included in Cyclodextrin During Drying a Single Drop

Good taste and flavor of the spray-dried powder products are the most important quality factors. In the present study, molecular encapsulation in cyclodextrin has been applied to prevent the loss of hydrophobic flavor compounds during drying. We have also proposed a new short-cut method for estimating flavor retention. We have applied this method to calculate the final retention of l-menthol encapsulated in a blend of β-cyclodextrin and maltodextrin during drying of a single droplet.

Improvement of l-Menthol Retention by Cyclodextrin During Drying

Various kinds of liquid foods have been dried in powder form by spray drying. The key technique in drying is to prevent the loss of volatile components in the food liquid. In this study, a molecular encapsulation method using cyclodextrins was used to improve the retention of hydrophobic flavor components during drying of a single droplet. Significant improvement of the 1-menthol retention was observed under various drying conditions. Numerical calculations based on the selective diffusion hypothesis could estimate well the final retention of l-menthol under various concentrations of cyclodextrin and maltodextrin.

Effect of Water and Alcohol on the Formation of Inclusion Complex between Cyclodextrins and d-Limonene by Twin Screw Kneader

To enhance the storage stability of essential oils such as d-limonene, the molecular inclusion complex powder of d-limonene in α- or β-cyclodextrin was made by using a twin screw kneader. The influence of water and alcohol content on the formation of the inclusion complex was studied in comparison with the inclusion complex by the micro-aqueous method. There were many differences in the quantity of the inclusion complex between the two methods, particularly at a low water content. For α-cyclodextrin, the addition of alcohol inhibited the formation of the inclusion complexes.

Removal and recovery of CO2 from fossil fuel power plant flue gas by gas absorption technique: Operation characteristics of physical absorption and reduced stripping combined process

Test study on the operation characteristics of physical absorption and reduced stripping combined process for the removal and recovery of CO 2 from fossil fuel power plant flue gas were carried out. It was found that this process had a possibility of practical application. This study was supported by a Grant-in-Aid for Scientific Research (No. 04203104) from the Ministry of Education, Science, and Culture of Japan.

Experimental analysis of aerobic wastewater treatment using a draft tube airlift reactor suspended with biologically active carbon particles.

二重管式エアリフト反応器に生物膜付着活性炭粒子を懸濁させて用いる水処理操作の実験的解析を行なった。まず二重管式エアリフト反応器の液循環速度および気液間物質移動容量係数を測定した。ついで液回分操作実験によって基質除去速度に対する初基質濃度, 溶存酸素濃度および温度の影響を検討した。その結果, 基質除去速度は基質濃度が150mg・l-1以上の領域では0次反応速度式に従い, 基質濃度が150mg・l-1以下の領域ではmonod型速度式に従うことが見出された。また0次反応の領域において反応速度は溶存酸素濃度の0.20乗に比例して増大し, みかけの活性化エネルギーは33.5kJ・mol-1の値を示した。液相連続操作のもとで空間時間を変化させて基質の反応率を測定した。反応率の実測値は二重管式エアリフト反応器内の液流れを完全混合とみなす解析によってうまく予測することができた。