早稲田大学 武岡先生、垣内先生との共同研究成果

小塚君おめでとう!!

Do Ultrafine Bubbles Work as Oxygen Carriers?

Kenta Kakiuchi, Tomoki Kozuka, Nobuyuki Mase, Takehiro Miyasaka, Norikazu Harii, and Shinji Takeoka

 

Abstract
Fine bubbles (FBs) are bubbles with sizes less than 100 μm and are divided into ultrafine bubbles (UFBs, < 1 μm) and microbubbles (MBs, 1–100 μm) depending on their size. Although FB aeration is known as a more efficient way than macrobubble aeration to increase the oxygen level in unoxygenated water, few reports have demonstrated whether dispersed UFBs work as oxygen carriers or not. Furthermore, oxygen supersaturation is one of the attractive characteristics of FB dispersion, but the reason is yet to be revealed. In this study, we evaluated the relationship between the FBs, especially UFB concentration, and oxygen content in several situations to reveal the two questions. The FB concentration and oxygen content were examined using particle analyzers and our developed oxygen measurement method, which can measure the oxygen content in FB dispersion, respectively. First, in the evaluations of the oxygen dispersion from UFBs with respect to the surrounding oxygen level, UFBs did become neither small nor diminish even in degassed water. Second, the changes in UFBs and oxygen content upon storage temperature and the existence of a lid during storage were evaluated, and there was no correlation between them. It means UFBs contribute little to the oxygen content in UFB dispersion. Furthermore, the oxygen content in the UFB dispersion decreased over time identically as that of the oxygen-supersaturated water with little UFBs. Third, we evaluated the relationship between FB concentration and oxygen content during FB generation by measuring them simultaneously. The results showed that dispersed MB and UFB concentrations did not account for the supersaturation of the FB dispersion. From the result, it was revealed that 100–200 nm of UFBs themselves did not work as oxygen carriers, and the oxygen supersaturation in FB dispersions was due to the supersaturated state of dissolved oxygen that was prepared during the FB generation process.

Do Ultrafine Bubbles Work as Oxygen Carriers? | Langmuir (acs.org)

Taylor’s大学 S. H. Mah先生との共同研究成果

Synthesis of benzylated amine‐substituted xanthone derivatives and their antioxidant and anti‐inflammatory activities – Wong – Archiv der Pharmazie – Wiley Online Library

Ka Woong Wong, Soek Sin Teh, Kung Pui Law, Intan Safinar Ismail, Kohei Sato, Nobuyuki Mase, Siau Hui Mah

Abstract

Oxidative stress and its constant companion, inflammation, play a critical part in the pathogenesis of many acute and chronic illnesses. The discovery of new multi-targeted drug candidates with antioxidant and anti-inflammatory properties is deemed necessary. Thus, a series of novel xanthone derivatives with halogenated benzyl (4b–4d, 4f–4h) and methoxylated benzyl groups (4e) attached to the butoxy amine substituent were synthesized in this study. The synthesized xanthone derivatives exhibited stronger antioxidant activity against H2O2 scavenging than the standard drug, α-tocopherol, but weaker towards DPPH scavenging and ferrous ion chelation. Besides that, 4b–4d, 4f–4h demonstrated good anti-inflammatory activities through NO production inhibition towards lipopolysaccharide (LPS)-induced RAW 264.7 cells and showed 2–4 times stronger effects than the standard drug, diclofenac sodium. Moreover, compound 4b with two brominated benzyl groups attached to the butoxy amine substituent suppressed the production of pro-inflammatory cytokines, TNF-α and IL-1β, significantly. Structure–activity relationship elucidated that the halogenated benzylamine substituent plays an important role in contributing the antioxidant and anti-inflammatory activities of xanthones. In summary, xanthone 4b was identified as a potential lead compound to be further developed into antioxidant and anti-inflammatory drugs. Thus, further studies on the related mechanisms of action of 4b are recommended.

スズキ歴史館訪問

IITH(インド工科大学ハイデラバード校)のCh.Subrahmanyam教授と博士課程のMadhu Kumar君、そして、IITH出身で間瀬研の博士課程のM. Arun Kumar君と、スズキ財団の計らいでスズキ歴史館を訪問しました。日本におけるものづくりの真髄を堪能し、どうやって車が出来上がるかを歴史と共に学んできました。

研究室見学

最近、ぽつぽつと問い合わせが来ておりますので、研究室見学に関する申込先をご紹介します。研究室選び、共同研究などにご活用ください。

研究室見学申込_間瀬 (office.com)

Prof. Ch.Subrahmanyam先生_来日

インド工科大学ハイデラバード校(Indian Institute of Technology Hyderabad)化学科のProf. Ch.Subrahmanyam先生が、コロナで大変の中、スズキ財団のサポートで静岡大学に研究にきてくれました。本当は、4月から9月までの予定でしたが、紆余曲折があって、本日の来日となりました。2か月の短い間ですが、研究するぞ~~~。

速報 小塚君 第11回JACI/GSCシンポジウム GSCポスター賞受賞

おめでとう!!

○小塚智貴・櫻井大斗・濱添光一・佐藤浩平・鳴海哲夫・間瀬暢之
「ファインバブル有機化学:環境調和型条件下での高効率気相―液相反応の実現」
第11回JACI/GSCシンポジウム、A-19、オンライン、2022/6/16

ポスター発表:226件
審査対象:200件
受賞:23件

第11回 JACI/GSCシンポジウム (jaci-gsc.com)

受賞者の声
この度、第11回JACI/GSCシンポジウムにてポスター賞を受賞いたしました。発表題目は「ファインバブル有機化学:環境調和型条件下での高効率気相-液相反応の実現」です。今回の学会では、ファインバブルによる気相ー液相反応の反応効率向上や、社会実装を志向したkgスケールの合成、定量分析に基づいたファインバブルの反応メカニズムについて発表させていただきました。質疑応答の場面では、まだまだ至らぬ点が多いことを痛感しましたが、このような賞を頂くことができ、今後の励みとなりました。最後に、私の研究をご指導してくださいました間瀬暢之先生、鳴海哲夫先生、佐藤浩平先生、研究室の皆さまに厚く御礼申し上げます。