Design and Synthesis of Highly Active Antimycobacterial Mutual Esters of 2-(2-Isonicotinoylhydrazineylidene)propanoic Acid

The combination of two active scaffolds into one molecule represents a proven approach in drug design to overcome microbial drug resistance. We designed and synthesized more lipophilic esters of 2-(2-isonicotinoylhydrazineylidene)propanoic acid, obtained from antitubercular drug isoniazid, with various alcohols, phenols and thiols, including several drugs, using carbodiimide-mediated coupling. Nineteen new esters were evaluated as potential antimycobacterial agents against drug-sensitive Mycobacterium tuberculosis (Mtb.) H37Rv, Mycobacterium avium and Mycobacterium kansasii. Selected derivatives were also tested for inhibition of multidrug-resistant (MDR) Mtb., and their mechanism of action was investigated. The esters exhibited high activity against Mtb. (minimum inhibitory concentrations, MIC, from ≤0.125 μM), M. kansasii, M. avium as well as MDR strains (MIC from 0.25, 32 and 8 µM, respectively). The most active mutual derivatives were derived from 4-chloro/phenoxy-phenols, triclosan, quinolin-8-ol, naphthols and terpene alcohols. The experiments identified enoyl-acyl carrier protein reductase (InhA), and thus mycobacterial cell wall biosynthesis, as the main target of the molecules that are activated by KatG, but for some compounds can also be expected adjunctive mechanism(s). Generally, the mutual esters have also avoided cytotoxicity and are promising hits for the discovery of antimycobacterial drugs with improved properties compared to parent isoniazid.

Lipid Nanoparticles Loaded with Farnesol or Geraniol to Enhance the Susceptibility of E. coli MCR-1 to Colistin

Resistance to colistin, one of the antibiotics of last resort against multidrug-resistant Gram-negative bacteria, is increasingly reported. Notably, MCR plasmids discovered in 2015 have now been reported worldwide in humans. To keep this antibiotic of last resort efficient, a way to tackle this mechanism seems essential. Terpene alcohols such as farnesol have been shown to improve the efficacy of some antibiotics. However, their high lipophilicity makes them difficult to use. This problem can be solved by encapsulating them in water-dispersible lipid nanoparticles (LNPs). The aim of this study was to discover, using checkerboard tests and time-kill curve experiments, an association between colistin and farnesol or geraniol loaded in LNPs, which would improve the efficacy of colistin against E. coli and, in particular, MCR-1 transconjugants. Then, the effect of the combination on E. coli inner membrane permeabilisation was evaluated using propidium iodide (PI) uptake and compared to human red blood cells plasma membrane permeabilisation. Both terpene alcohols were able to restore the susceptibility of E. coli J53 MCR-1 to colistin with the same efficacy (Emax = 16, i.e., colistin MIC was decreased from 8 to 0.5 mg/L). However, with an EC50 of 2.69 mg/L, farnesol was more potent than geraniol (EC50 = 39.49 mg/L). Time-kill studies showed a bactericidal effect on MCR-1 transconjugant 6 h after incubation, with no regrowth up to 30 h in the presence of 1 mg/L colistin (1/8 MIC) and 60 mg/L or 200 mg/L farnesol or geraniol, respectively. Colistin alone was more potent in increasing PI uptake rate in the susceptible strain (EC50 = 0.86 ± 0.08 mg/L) than in the MCR-1 one (EC50 = 7.38 ± 0.85 mg/L). Against the MCR-1 strain, farnesol-loaded LNP at 60 mg/L enhanced the colistin-induced inner membrane permeabilization effect up to 5-fold and also increased its potency as shown by the decrease in its EC50 from 7.38 ± 0.85 mg/L to 2.69 ± 0.25 mg/L. Importantly, no hemolysis was observed for LNPs loaded with farnesol or geraniol, alone or in combination with colistin, at the concentrations showing the maximum decrease in colistin MICs. The results presented here indicate that farnesol-loaded LNPs should be studied as combination therapy with colistin to prevent the development of resistance to this antibiotic of last resort.

The effectiveness analysis of technological and biotechnological methods for production of dry wines from ‘Muscat Blanc’ grape variety

В статье рассматривается эффективность технологических и биотехнологических приемов при производстве сухих вин из винограда сорта Мускат белый. Показано, что предбродильная аэрация дрожжевой культуры приводит к формированию более окисленного фенольного комплекса виноматериалов. Значимым фактором формирования фенольного комплекса является режим сульфитации сусла: введение 75 мг/дм SO способствует увеличению содержания фенольных компонентов в виноматериалах в 1,5 раза по сравнению с несульфитированным суслом. Установлено, что штаммы дрожжей Ленинградская и Севастопольская 23 в процессе брожения синтезируют ацетальдегид в малых количествах; сульфитация сусла увеличивает содержание ацетальдегида в виноматериалах, полученных на культуре Севастопольская 23, в 1,6 раза. Показано, что в условиях длительного брожения сусла без доступа воздуха возрастает роль дрожжей в формировании терпеновых спиртов виноматериалов; обработка сусла оклеивающими препаратами способствует образованию терпенов дрожжами. По результатам органолептического тестирования виноматериалов определена совокупность приемов, позволяющих получать сухие виноматериалы из винограда Мускат белый с выраженным сортовым ароматом и вкусом. Эти приемы включают длительное брожение без доступа воздуха при температуре 16-18С с использованием расы дрожжей Севастопольская 23, сусла, сульфитированного до 75 мг/дм SO и обработанного оклеивающими препаратами - в случае традиционного виноделия; самоосветленного сусла без введения диоксида серы - в случае органического виноделия. The article considers the effectiveness of technological and biotechnological methods for production of dry wines from grapes of ‘Muscat Blanc’ variety. It is shown that pre-fermentation aeration of yeast culture leads to the formation of a more oxidized phenolic complex of base wines. A significant factor of phenolic complex formation is the process of must sulfiting: the introduction of 75 mg/dm of SO promotes to increasing the content of phenolic components in base wines by 1.5 times in comparison with unsulfited must. It is established that yeast strains ‘Leningradskaya’ and ‘Sevastopolskaya 23’ synthesize acetaldehyde in small quantities in the process of fermentation; must sulfiting increases the content of acetaldehyde in base wines obtained using culture ‘Sevastopolskaya 23’ by 1.6 times. It is shown that role of the yeast in the formation of base wine terpene alcohols increases under conditions of long anaerobic must fermentation; must processing with fining agents promotes to the terpene formation by the yeast. Based on the results of organoleptic base wine testing, a set of methods for obtaining dry base wines from grapes of ‘Muscat Blanc’ variety with a pronounced varietal aroma and flavor was determined. These methods include long anaerobic fermentation at a temperature of 16-18°C using the yeast race ‘Sevastopolskaya 23’, must sulfited to 75 mg/dm of SO and treated with fining agents - in case of traditional winemaking; self-clarified must without sulfur dioxide introduction - in case of organic winemaking.

Application of Hanseniaspora vineae Yeast in the Production of Rosé Wines from a Blend of Tempranillo and Albillo Grapes

Hanseniaspora vineae is an apiculate yeast that can be used for the production of interesting commercial wines, due to its contribution of fermentative volatiles. This paper presents a detailed comparative study of the use of H. vineae, compared to pure fermentations of S. cerevisiae in Tempranillo and Albillo rosé wines. Fermentations were carried out in oak barrels and stainless steel barrels. The results indicated that fermentation with H. vineae resulted in wines with residual sugars below 3.4 g/L and similar general characteristics, compared to S. cerevisiae. However, H. vineae wines contain up to 44% more total anthocyanins, resulting in an appreciable improvement in colour. In addition, H. vineae produced up to 65% more 2-phenylethyl acetate in stainless steel barrels and 2.5 times more terpene alcohols in oak barrels. Therefore, the use of H. vineae results in a more attractive colour, as well as fruity and floral organoleptic characteristics of rosé wines.

Biocatalytic synthesis of terpene esters and their biological activity in human glioma cells

Background: Gliomas are highly malignant brain tumors with high resistance to chemotherapy. Therefore, investigations of new therapeutic molecules with high anti-glioma activity are of great importance. Objective: In this work, biocatalytic esterification of terpene alcohols with proven anti-cancer activity was performed to enhance their potency to induce cell death in human glioblastoma multiforme T98G and anaplastic astrocytoma MOGGCCM cell lines in vitro. Method and Results: We used primary terpene alcohols and carboxylic acids with a length of two to nine carbon atoms. The structure of the drinks influenced the esterification efficiency, which decreased in the following order: monocyclic > linear > bicyclic. Terpene alcohols and their esters only induced apoptotic cell death, which is highly desirable from a therapeutic point of view but did not induce autophagy and necrosis. The esterification of perillyl alcohol with butyric acid caused a 4-fold increase in cell death induction in the T98G line. Citronellol valerate, caprylate, and pelargonate and myrtenol butyrate, caprylate, and pelargonate also showed higher activity than their alcohol precursors. Conclusion: We have herein shown that esterification of natural alcohols by biocatalysis can improve the activity for other compounds investigated for their anti-glioma activity.

Perspective Yeast Races for Young Sparkling Wines with a Muscat Aroma

Introduction. In order to solve the growing demand for Muscat sparkling wines, some of the Muscat grapes used for the production of liqueur wines should be used as a raw material for sparkling wines. The technology of preparing young sparkling wines has a shorter production cycle. Science-based selection of the yeast race makes it possible to obtain young sparkling wines with a clear and bright Muscat aroma. Study objects and method. The research featured young sparkling wines from White Muscat grapes, produced using different yeasts races. The research involved both standard and modified methods of enochemical analysis. Results and discussion. The LALVIN QA-23 and Odesskiy Cherniy-SD-13 yeast races demonstrated a more active fermentation of Muscat white wort. The Sevastopolskaya 23 sample had in a slower fermentation, which promoted a greater accumulation of bound forms of carbon dioxide (16%). It contained the smallest amount of residual sugars (2 g/dm3) and thriable acids (6 g/dm3) and the largest amount of polyphenols (103 mg/dm3) and amine nitrogen (91 mg/dm3). Two samples accumulated a sufficient amount of free terpenes: 1.16 mg/dm3 for LALVIN QA-23 and 1.13 mg/dm3 for Sevastopolskaya 23. The degustation scores were quite high: LALVIN QA-23 received 9.03 points and Odesskiy Cherniy-SD-13 – 9.02 points, while Sevastopolskaya 23 scored 9.00 points. The LALVIN QA-23 sample proved to have the most pronounced varietal aroma, whereas the Odesskiy Cherniy-SD-13 sample possessed a more complex aromatic complex. Conclusion. The LALVIN QA-23 and Sevastopolskaya 23 yeast races were found suitable for bottle champagnization of young Muscat sparkling wines. They accumulated a sufficient amount of terpene alcohols. The samples had a clear Muscat aroma, harmonious taste, and good typical properties. The new method makes it possible to produce high quality sparkling wines in the harvest year.

The effect of yeast strains on the formation of aroma complex of base wines from 'Tsitronnyi Magaracha' grape variety

Одним из важных современных направлений виноделия является получение высококачественных вин с узнаваемой сортовой индивидуальностью. В данном аспекте наиболее привлекательными для потребителя являются вина из мускатных сортов винограда. Pабота посвящена изучению влияния штаммов дрожжей рода Saccharomyces на формирование сортового аромата виноматериалов из винограда сорта Цитронный Магарача и отбору перспективных штаммов для их производства. Объектами исследования являлись виноматериалы, приготовленные с использованием 20 штаммов дрожжей вида S. cerevisiae. В результате хроматографического анализа было идентифицировано 17 компонентов, относящихся к различным группам химических соединений: высшим спиртам, сложным эфирам, терпеновым спиртам. Исследуемые штаммы способствовали накоплению в виноматериалах терпеновых спиртов в концентрации от 0,46 до 1,51 мг/л, высших спиртов - от 153,86 до 263,89 мг/л, сложных эфиров - от 3,96 до 19,09 мг/л. По результатам органолептической оценки опытных образцов для производства вин из винограда сорта Цитронный Магарача рекомендованы два коллекционных штамма Алиготе М (I-76) и Мускат 4 (Р) (I-637) из КМВ «Магарач». Использование данных штаммов позволило получить виноматериалы с ярким развитым ароматом цветочно-фруктового направления с проявлением тонов цитрусовых и розы. Отмечено, что штамм Алиготе М (I-76) способствовал обогащению виноматериалов терпеновыми спиртами и сложными эфирами, штамм Мускат 4 (Р) (I-637) - сложными эфирами. One of the important modern trends in winemaking is the production of high quality wines with recognizable varietal identity. In this aspect, the most attractive for consumers are the wines from muscat grape varieties. The work is devoted to the study of the effect of yeast strains of the Saccharomyces genus on the formation of varietal aroma of base wines from grapes of 'Tsitronnyi Magaracha' variety and selection of promising strains for their production. The objects of the study were base wines prepared using 20 strains of S. cerevisiae yeast species. As a result of chromatographic analysis, 17 components of various groups of chemical compounds were identified: higher alcohols, esters, terpene alcohols. The studied strains contributed to the accumulation of terpene alcohols in concentration from 0.46 to 1.51 mg/l, higher alcohols - from 153.86 to 263.89 mg/l, esters - from 3.96 to 19.09 mg/l. According to the results of organoleptic evaluation of experimental samples for wine production from grapes of 'Tsitronnyi Magaracha' variety, two strains 'Aligote M' (I-76) and 'Muscat 4' (P) (I-637) from the Magarach Collection of Microorganisms of Winemaking are recommended. The use of these strains have made it possible to obtain base wines with advanced rich aroma of a floral-fruity direction with demonstration of citrus and rose hues. It was noted that the strain 'Aligote M' (I-76) contributed to the enrichment of base wines with terpene alcohols and esters, the strain 'Muscat 4' (P) (I-637) - with esters.