{"title":"The generation of hydrogen peroxide and antibacterial effectiveness by copper oxide surface layers.","authors":"Yurika Taniguchi, Hiroshi Kawakami, Sadao Komemushi, Ken Hirota, Takashi Ozawa, Kazunori Miyamoto, Hiroaki Nakayama, Masahiko Wada","doi":"10.4265/jmc.30.1_19","DOIUrl":"10.4265/jmc.30.1_19","url":null,"abstract":"<p><p>Copper is known as an antibacterial material. Reactive oxygen species (ROS) with antibacterial effectiveness are generated on copper surfaces mainly by the Fenton-type reaction. The antibacterial effectiveness is higher in Cu<sub>2</sub>O than in CuO. In this study we discussed the effects of the difference in the amount of generated ROS on the difference in the antibacterial effectiveness between Cu<sub>2</sub>O and CuO. Both Cu<sub>2</sub>O and CuO produced hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>), hydroxyl radical(・OH), and singlet oxygen (<sup>1</sup>O<sub>2</sub>), but not superoxide radical (・O<sub>2</sub><sup>-</sup>). The concentration of H<sub>2</sub>O<sub>2</sub> produced was higher in Cu<sub>2</sub>O than in CuO. When catalase, a scavenger of H<sub>2</sub>O<sub>2</sub>, was added, the antibacterial activities of both Cu<sub>2</sub>O and CuO reduced to almost the same value. These experimental results indicate that Cu<sub>2</sub>O is higher in antibacterial effectiveness than CuO because Cu<sub>2</sub>O produced more H<sub>2</sub>O<sub>2</sub> than CuO. As ・OH was detected even when H<sub>2</sub>O<sub>2</sub> was scavenged by catalase before it reacted with Cu ion, a part of ・OH was generated by chemical reactions different from the Fenton-type reaction when copper oxides were in contact with water.</p>","PeriodicalId":73831,"journal":{"name":"Journal of microorganism control","volume":"30 1","pages":"19-26"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143732589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Synthesis of the sophoroselipid-copper complex and its bactericidal properties.","authors":"Yuichi Kumashita, Hiroki Masuda, Taichi Kamo, Reiko Matsumura, Miho Sasaki, Yoshihiko Hirata, Yoshinobu Matsumura","doi":"10.4265/jmc.30.2_41","DOIUrl":"https://doi.org/10.4265/jmc.30.2_41","url":null,"abstract":"<p><p>The copper (II) ion is valuable as an antimicrobial reagent and is highly safe for humans, animals, plants, and the environment. In this study, the effect of sodium sophoroselipid (SL-Na) on the bactericidal activity of CuSO<sub>4</sub> was investigated. SL-Na enhanced the bactericidal activity of CuSO<sub>4</sub> when incubated with it for 10 min or more at 20℃. Its bactericidal activity is significant against gram-negative bacterial cells. CuSO<sub>4</sub> at a concertation of 100 µM, when mixed with 100 µM SL-Na, effectively killed Escherichia coli cells at a rate of more than one order of magnitude higher than that observed without SL-Na after 30 minutes at 20℃. The structural differences between SL-Na, CuSO<sub>4</sub> and their mixture were confirmed by ultraviolet visible absorption spectrum analyses, resulting in the absorption of ca. 800 nm derived from copper (II) ions shifting to ca. 680 nm in the mixture. This shift suggests that the acid-form sophoroselipids and copper (II) ions bind weakly to form a complex (SL-Cu complex). The purified SL-Cu complex also revealed a unique absorption at approximately 1,600 cm<sup>-1</sup> using a Fourier transform infrared analysis and demonstrated a higher bactericidal activity than CuSO<sub>4</sub>. Our results indicate that SL-Cu complex formation enhanced the bactericidal activity of copper (II) ions.</p>","PeriodicalId":73831,"journal":{"name":"Journal of microorganism control","volume":"30 2","pages":"41-48"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144509846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Oral local factors affecting candida colonization in patients undergoing perioperative oral care.","authors":"Kei Fujishima, Tetsuya Sakuta, Naofumi Tamaki","doi":"10.4265/jmc.30.1_27","DOIUrl":"10.4265/jmc.30.1_27","url":null,"abstract":"<p><p>Recently, perioperative oral function management, focusing on oral care, has been considered important from the perspective of preventing infections caused by oral microorganisms. One of the infectious diseases that should be prevented is oral candidiasis. The purpose of this study was to clarify the oral local factors related to Candida colonization in perioperative patients. The analyses of the relationship between oral local factors and Candida colonization revealed that three factors - a reduction in the number of remaining teeth, wearing dentures, and increased dry mouth - were related to Candida colonization. The oral local factors related to Candida colonization identified in this study may be useful indicators for easily and quickly determining whether or not Candida colonization is present. It is difficult to perform bacteriological tests on all perioperative patients, who are subject to various constraints, including physical, mental, and time constraints, so we hope that oral examinations focusing on these oral local factors would provide a foothold in preventing the onset of oral candidiasis in perioperative patients.</p>","PeriodicalId":73831,"journal":{"name":"Journal of microorganism control","volume":"30 1","pages":"27-31"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143732588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of peracetic acid cleaning agents on biofilms by Methylobacterium spp. derived from hemodialysis equipment.","authors":"Eiichi Osono, Kazumi Honda, Yuki Inoue, Kyoko Ichimura, Hideki Negishi, Takuya Kumagai, Takeo Shimizu, Naoya Miyazawa, Mizuki Tomita, Akane Kobayashi, Ryoichi Akiyama, Chisako Kamano, Shun Takaku, Toshio Akimoto, Yoshihiko Norose, Rimpei Morita","doi":"10.4265/jmc.30.2_49","DOIUrl":"https://doi.org/10.4265/jmc.30.2_49","url":null,"abstract":"<p><p>We evaluated the efficacy of peracetic acid (PAA) products in disinfecting Methylobacterium radiotolerans biofilms within hemodialysis systems, using a Centers for Disease Control and Prevention (CDC) biofilm reactor. Twelve PAA products were tested with an appropriate neutralization. All products completely eradicated planktonic bacteria within 10 minutes. In contrast, the effectiveness against biofilms varied, with log reduction values (LRVs) ranging from 2.47 to 9.40, depending on PAA concentration. Products with higher hydrogen peroxide concentrations achieved greater LRVs at the same PAA concentrations, although its effect was secondary. Similar to sodium hypochlorite, extended reaction times further improved LRVs, even at higher dilutions. These findings suggest that PAA products are promising alternatives for the routine biofilm control in dialysis systems.</p>","PeriodicalId":73831,"journal":{"name":"Journal of microorganism control","volume":"30 2","pages":"49-53"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144509844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Volatilization and disinfection efficacy of gaseous hypochlorous acid from an air washer-type humidifier in a large space.","authors":"Shun Nojima, Soshi Omura, Satoshi Fukuzaki","doi":"10.4265/jmc.29.3_105","DOIUrl":"https://doi.org/10.4265/jmc.29.3_105","url":null,"abstract":"<p><p>An air washer-type humidifier has two useful functions: humidification, and air purification, and it applies to large indoor spaces. In this study, the efficacy of an air washer-type humidifier fed with 24 L of weakly acidic electrolyzed water(WAEW) at pH 5.0 and 30 mg/L in disinfecting attached bacteria and airborne microorganisms was studied in a 480 <sup>m3</sup> indoor space. The humidifier was operated at a shower volume of 9.0 L/min of WAEW and at an air flow rate of 29 <sup>m3</sup>/min. Volatilization of gaseous hypochlorous acid(HOCl<sub>(g)</sub>) proceeded according to first-order kinetics during the 60 min of operation. Fresh WAEW was supplied to the humidifier every 60 min, and the HOCl<sub>(g)</sub> concentration in the indoor space was maintained within the range of 25-52 ppb for at least 180 min of operation. The number of viable bacterial cells on wet agar plates placed on the floor at a distance of 5-20 m away from the humidifier decreased by 2.0-3.0 log after 30 min of operation, and no viable cells were detected after 60 min of operation. A logarithmic reduction of more than 2.7 was achieved within 15 min against bacteria-attached plates placed at a 1.5 m-height position where the outlet airflow from the humidifier was directly exposed. This indicates that the disinfection efficacy of HOCl<sub>(g)</sub> volatilized from the humidifier depends on the rate of outlet airflow reaching the bacteria-attached plates. The number of viable airborne microorganisms decreased by approximately 54% after 180 min of operation. This study demonstrated that an air-washer-type humidifier can spread HOCl<sub>(g)</sub> evenly throughout a large indoor space and is effective in disinfecting attached bacteria and airborne microorganisms.</p>","PeriodicalId":73831,"journal":{"name":"Journal of microorganism control","volume":"29 3","pages":"105-111"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142333903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Ethambutol inhibited the growth of acid-fast bacteria and enhanced the detection of Legionella in environmental water samples.","authors":"Hiroaki Inoue, Marin Taguchi, Manami Kitazume, Yukie Saito, Tomoyuki Iwasawa","doi":"10.4265/jmc.29.1_1","DOIUrl":"10.4265/jmc.29.1_1","url":null,"abstract":"<p><p>The growth of acid-fast bacteria often hinders the detection of Legionella in water samples on agar plates by the plate culture method. We studied whether anti-tubercular agents inhibit acid-fast bacteria growth on agar plates. First, the antimicrobial activities of isoniazid, ethionamide, and ethambutol were evaluated against Mycobacterium and Legionella. We found that ethambutol at ≥ 100 μg/mL completely inhibited Mycobacterium growth, but ethambutol at 1,000 μg/mL did not inhibit Legionella growth. Next, the effect of ethambutol dissolved in acid buffer was examined. Cell suspensions of L. pneumophila and Mycobacterium spp. were mixed, and ethambutol-acid buffer was added. After 5 min, mixtures were inoculated on GVPC agar plates and incubated at 36℃ for 6 d. We found that ethambutol inhibited Mycobacterium growth on agar plates, but the Legionella colonies recovered. The effect of ethambutol was also significant in the evaluation using bathwaters. Comparing 1,302 bathwaters, the addition of ethambutol reduced the detection rate of acid-fast bacteria from 30.6% to 0% and increased the detection rate of Legionella from 7.1% to 7.5%. Ethambutol, which selectively inhibited acid-fast bacteria growth, enhanced the detection of Legionella on agar plates and will contribute to improving the accuracy of Legionella testing by the plate culture method.</p>","PeriodicalId":73831,"journal":{"name":"Journal of microorganism control","volume":"29 1","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140178061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"External quality control survey on identification of microorganisms using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.","authors":"Kazuyuki Sogawa, Azumi Fujinaga, Hajime Okumura, Makiko Kiyosuke, Syota Murata, Koji Kusaba, Kohei Uechi, Kazuki Horiuchi, Kazunari Yasuda, Masami Murakami, Tomohiro Nakayama","doi":"10.4265/jmc.29.1_49","DOIUrl":"10.4265/jmc.29.1_49","url":null,"abstract":"<p><p>Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry( MALDI-TOF MS) is a bacterial typing tool that was approved as a medical device in 2011. However, external accuracy control examination of bacterial typing using mass spectrometry is still only performed on a small scale. In this study, E. faecium and S. maltophilia were selected and tested according to established procedures using Score Values at 228 institutions. The Score Values for MALDI Biotyper were 2.43±0.08 for E. faecium and 2.38±0.08 for S. maltophilia; and those for VITEK MS/PRIME were 99.9±0.0 for E. faecium and S. maltophilia. These results suggest that it is useful to evaluate external accuracy control with Score Values using the procedures we have developed.</p>","PeriodicalId":73831,"journal":{"name":"Journal of microorganism control","volume":"29 1","pages":"49-53"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140178062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Heparinoid enhances the efficacy of a bactericidal agent by preventing Cutibacterium acnes biofilm formation via quorum sensing inhibition.","authors":"Shoko Hamada, Sayaka Minami, Mitsuhiro Gomi","doi":"10.4265/jmc.29.1_27","DOIUrl":"10.4265/jmc.29.1_27","url":null,"abstract":"<p><p>Cutibacterium acnes is an opportunistic pathogen in acne vulgaris. C. acnes produces autoinducer-2 (AI-2), a signaling molecule used for communication known as quorum sensing (QS). In C. acnes, QS reportedly upregulates biofilm formation leading to resistance against bactericidal agents. In this study, we analyzed how heparinoid affected QS and biofilm formation of the opportunistic pathogen C. acnes. We also verified whether heparinoid would suppress biofilm formation and enhance the efficacy of the bactericidal agent 4-isopropyl-3-methylphenol (IPMP) against C. acnes biofilms. We ran an AI-2 bioassay using Vibrio harveyi ATCC BBA-1121. Heparinoid exhibited inhibitory activity against AI-2 at concentrations of 0.003-0.005%, suggesting an AI-2 analog-derived or C. acnes culture supernatant-derived inhibition of the AI-2 activity. To evaluate how heparinoid suppresses biofilm formation in C. acnes, we completed a biofilm assay in 96-well plates. We also evaluated the bactericidal activity of IPMP against the C. acnes biofilm prepared with or without heparinoid. Heparinoid inhibited C. acnes biofilm formation and IPMP bactericidal efficacy increased upon heparinoid-mediated suppression of biofilm formation. In this study, we clarified that heparinoid inhibits the AI-2-mediated QS of C. acnes, thereby suppressing biofilm formation and increasing IPMP bactericidal efficacy, potentially suppressing acne vulgaris.</p>","PeriodicalId":73831,"journal":{"name":"Journal of microorganism control","volume":"29 1","pages":"27-31"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140178063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mohammad Tamrin Mohamad Lal, Leong Seng Lim, Lik-Ming Lau, Elden Sai Long Chang, Asyraf Abdul Momin, Muhd Sharil Izzan Hamid
{"title":"Fungal infections and control strategies in cultured marine finfish: a minireview.","authors":"Mohammad Tamrin Mohamad Lal, Leong Seng Lim, Lik-Ming Lau, Elden Sai Long Chang, Asyraf Abdul Momin, Muhd Sharil Izzan Hamid","doi":"10.4265/jmc.29.4_127","DOIUrl":"https://doi.org/10.4265/jmc.29.4_127","url":null,"abstract":"<p><p>Marine fish farming served as a sustainable alternative to capture fisheries. However, it faced challenges such as disease management, water quality maintenance, and minimizing environmental impacts. Among these challenges, fungal infections are particularly concerning. Traditionally, chemical treatments raise concerns about potential toxicity to fish and humans, environmental impact, and resistance development. In response to these issues, there is growing interest in sustainable biocontrol strategies, including the use of probiotics, phytobiotics, postbiotics, microalgae, and fungal parasites as antifungal agents. This mini-review provides a brief overview of fungal infections in marine fish and discusses current fungal biocontrol strategies in aquaculture. By adopting these sustainable control methods, the aquaculture industry can improve fish health and productivity while reducing its reliance on harmful chemicals.</p>","PeriodicalId":73831,"journal":{"name":"Journal of microorganism control","volume":"29 4","pages":"127-132"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142980923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hyojin Gim, Sangah Hong, Hyungyung Park, Sunghyun Im, Jong Il Kim
{"title":"Synergistic/antagonistic antimicrobial effects of cosmetic ingredients in combination with 1,2-hexanediol.","authors":"Hyojin Gim, Sangah Hong, Hyungyung Park, Sunghyun Im, Jong Il Kim","doi":"10.4265/jmc.29.4_133","DOIUrl":"10.4265/jmc.29.4_133","url":null,"abstract":"<p><p>With the rise of the clean beauty trend in the cosmetics and personal care industry, consumers' interest in cosmetic ingredients, especially preservatives, continues to grow. Paraben, previously the most used preservative in cosmetics, has been excluded from many products owing to its potential risks. Therefore, a movement to lower the content of various preservatives is ongoing. One approach to achieve a suitable level of preservation is to use multifunctional ingredients as preservative boosters. In this study, we aimed to confirm the synergistic antimicrobial interactions between various cosmetic ingredients and 1,2-hexanediol, a preservative introduced as a substitute for paraben, using the checkerboard assay. We also measured the antagonistic effect by measuring the fold changes in the minimum inhibitory concentration of 1,2-hexanediol. Niacinamide, a form of vitamin B3, showed synergistic antifungal activity with 1,2-hexanediol, which lowered the content of 1,2-hexanediol in the oil-solubilized toner formulation. Among the substances, 50000 ppm of methyl methacrylate crosspolymer elevated the minimum inhibitory concentration of 1,2-hexanediol against bacteria and fungi by 2‒8 times. Through this study, we suggest applying the synergistic effects of various cosmetic ingredients in the formulation as a method to effectively reduce the content of preservatives.</p>","PeriodicalId":73831,"journal":{"name":"Journal of microorganism control","volume":"29 4","pages":"133-142"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142980926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}