Physical properties and antifungal activity of bioactive films containing Wickerhamomyces anomalus killer yeast and their application for preservation of oranges and control of postharvest green mold caused by Penicillium digitatum

Abstract Candidiasis is a group of opportunistic infections caused by yeast of the genus Candida. The appearance of drug resistance and the adverse effects of current antifungal therapies require the search for new, more efficient therapeutic alternatives. Killer yeasts have aroused as suitable candidates for mining new antifungal compounds. Killer strains secrete antimicrobial proteins named killer toxins, with promissory antifungal activity. Here we found that the killer yeast Wickerhamomyces anomalus Cf20 and its cell-free supernatant (CFS) inhibited six pathogenic strains and one collection strain of Candida spp. The inhibition is mainly mediated by secreted killer toxins and, to a lesser extent, by volatile compounds such as acetic acid and ethyl acetate. A new large killer toxin (>180 kDa) was purified, which exerted 70–74% of the total CFS anti-Candida activity, and the previously described glucanase KTCf20 was inhibitory in a lesser extent as well. In addition, we demonstrated that Cf20 possesses the genes encoding for the β-1,3-glucanases WaExg1 and WaExg2, proteins with extensively studied antifungal activity, particularly WaExg2. Finally, the 10-fold concentrated CFS exerted a high candidacidal effect at 37°C, completely inhibiting the fungal growth, although the nonconcentrated CFS (RCF 1) had very limited fungistatic activity at this temperature. In conclusion, W. anomalus Cf20 produces different low and high molecular weight compounds with anti-Candida activity that could be used to design new therapies for candidiasis and as a source for novel antimicrobial compounds as well.

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Citronellal Exerts Its Antifungal Activity by Targeting Ergosterol Biosynthesis in Penicillium digitatum

Journal of Fungi ◽

10.3390/jof7060432 ◽

2021 ◽

Vol 7 (6) ◽

pp. 432

Author(s):

Qiuli OuYang ◽

Yangmei Liu ◽

Okwong Reymick Oketch ◽

Miaoling Zhang ◽

Xingfeng Shao ◽

...

Keyword(s):

Antifungal Activity ◽

Antifungal Agents ◽

Inhibitory Concentration ◽

Membrane Integrity ◽

Penicillium Digitatum ◽

Ergosterol Biosynthesis ◽

Cell Membrane Integrity ◽

Minimum Fungicidal Concentration ◽

Green Mold ◽

Erg Genes

Ergosterol (ERG) is a potential target for the development of antifungal agents against Penicillium digitatum, the pathogen of green mold in citrus fruits. This study examined the mechanism by which citronellal, a typical terpenoid of Cymbopogon nardus essential oil, acts on ergosterol to exhibit its antifungal activity against P. digitatum. We previously reported that citronellal inhibited the growth of P. digitatum with minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of 1.36 and 2.72 mg/mL, respectively. In citronellal-treated cells, the membrane integrity and ergosterol contents significantly decreased, whereas lanosterol, which serves as a precursor for ergosterol biosynthesis, massively accumulated. Addition of 150 mg/L of exogenous ergosterol decreased the inhibitory rate of citronellal, restoring the ergosterol content and hence the membrane structure to normal levels, and triggered expression of nearly all ERG genes. Based on our findings, we deduce that citronellal damages the cell membrane integrity of P. digitatum by down-regulating the ERG genes responsible for conversion of lanosterol to ergosterol, the key downregulated gene being ERG3, due to the observed accumulation of ergosta-7,22-dienol.

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Kimberlite Volcanology: Transport, Ascent, and Eruption

Elements ◽

10.2138/gselements.15.6.405 ◽

2019 ◽

Vol 15 (6) ◽

pp. 405-410 ◽

Cited By ~ 3

Author(s):

J. Kelly Russell ◽

R. Stephen J. Sparks ◽

Janine L. Kavanagh

Keyword(s):

Physical Properties ◽

Small Degree ◽

Magma Ascent ◽

Volcanic Deposits ◽

And Control

Kimberlite rocks and deposits are the eruption products of volatile-rich, silica-poor ultrabasic magmas that originate as small-degree mantle melts at depths in excess of 200 km. Many kimberlites are emplaced as subsurface cylindrical-to-conical pipes and associated sills and dykes. Surficial volcanic deposits of kimberlite are rare. Although kimberlite magmas have distinctive chemical and physical properties, their eruption styles, intensities and durations are similar to conventional volcanoes. Rates of magma ascent and transport through the cratonic lithosphere are informed by mantle cargo entrained by kimberlite, by the geometries of kimberlite dykes exposed in diamond mines, and by laboratory-based studies of dyke mechanics. Outstanding questions concern the mechanisms that trigger and control the rates of kimberlite magmatism.

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Antifungal activity of components used for decontamination of dental prostheses on the growth of Candida albicans

Revista de Odontologia da UNESP ◽

10.1590/rou.2014.018 ◽

2014 ◽

Vol 43 (2) ◽

pp. 137-142 ◽

Cited By ~ 2

Author(s):

Cíntia Lima Gouveia ◽

Isabelle Cristine Melo Freire ◽

Maria Luísa de Alencar e Silva Leite ◽

Rebeca Dantas Alves Figueiredo ◽

Leopoldina de Fátima Dantas de Almeida ◽

...

Keyword(s):

Candida Albicans ◽

Antifungal Activity ◽

Sodium Bicarbonate ◽

Fungal Growth ◽

Antifungal Effect ◽

Dental Prostheses ◽

Diffusion Technique ◽

Zones Of Inhibition ◽

And Control

Introduction: The effectiveness of antimicrobial solutions employed in dental prosthesis decontamination is still uncertain. Aim: To evaluate the antifungal activity of cleaners used in the decontamination of dental prostheses on the growth of Candida albicans. Material and method: The evaluated products were: Corega Tabs(r) (S1), Sodium Hypochlorite 1% (S2), Sodium Bicarbonate 1% (S3), Hydrogen Peroxide 1% (S4), Chlorhexidine Digluconate 0.12% - Periogard (r) (S5), Mouthrinse based on essential oils - Listerine(r) (S6), essential oil from Rosmarinus officinalis (rosemary) at concentrations of 1% (S7) and 2% (S8). The antifungal activity of the products was evaluated by agar diffusion technique and the determination of microbial death curve of samples of C. albicans (ATCC 90028) in concentration 1.5 × 106 CFU/mL. The tests were performed in triplicate and statistical analysis was made by ANOVA Two-Way and Tukey tests, with the confidence level of 95%. Result: The average of the zones of inhibition growth, in millimeters, obtained for the products were: 0.0 (S1), 44.7 (S2), 0.0 (S3), 21.6 (S4), 10.0 (S5), 6.1 (S6), 0.0 (S7) and 2.4 (S8). Considering the determination of microbial death curve, all products showed a statistical difference (p<0.01) from control (0.85% sodium chloride) and S3 groups. Fungal growth less than 2×104 CFU/mL and an accentuation of the microbial death curve were observed after 30 minutes, with exception for S3 and control groups. Conclusion: The studied compounds, with the exception of Sodium Bicarbonate, have antifungal effect against C. albicans, which contribute for dental prostheses hygiene.

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Pengaruh Substitusi Tepung Terigu dengan Tepung Umbi Dahlia dan Konsentrasi Baking Powder terhadap Karakteristik Fisik Cookies Kaya Serat

Jurnal Aplikasi Teknologi Pangan ◽

10.17728/jatp.5864 ◽

2020 ◽

Vol 9 (4) ◽

pp. 175-180

Author(s):

Ahmad Zaki Mubarok ◽

Ardelia Winata

Keyword(s):

Physical Properties ◽

Wheat Flour ◽

Desirability Function ◽

High Fiber ◽

Powder Concentration ◽

Wide Range ◽

Powder Addition ◽

Derringer’S Desirability Function ◽

Optimum Formula ◽

And Control

Cookies merupakan salah satu makanan ringan yang disukai disemua kalangan umur. Umumnya cookies terbuat dari tepung terigu, memiliki kandungan karbohidrat dan lemak yang tinggi namun mengandung kadar serat yang rendah. Pada penelitian ini tepung umbi dahlia digunakan sebagai substitusi tepung terigu untuk pembuatan cookies kaya serat. Tujuan dari penelitian ini adalah untuk mengkaji penggunaan tepung umbi dahlia sebagai substitusi tepung terigu dan konsentrasi baking powder dalam formulasi pembuatan cookies. Rasio tepung umbi dahlia dan tepung terigu pada penelitian ini yaitu 15:85, 30:70, dan 45:55; dan konsentrasi baking powder yang digunakan yaitu 1–3% dari berat tepung. Metode Derringer’s Desirability Function digunakan untuk mendapatkan formula terbaik, dengan membandingkan kedekatan nilai karakteristik fisik cookies yang diberi perlakuan dengan karakteristik fisik cookies kontrol sebagai target. Hasil penelitian ini didapatkan formula terbaik untuk pembuatan cookies kaya serat adalah penggunaan rasio tepung umbi dahlia dan tepung terigu sebesar 30:70 dan penggunaan baking powder konsentrasi 3% dengan nilai total desirability (D) sebesar 0,87. Kesimpulan dari penelitian ini adalah cookies kaya serat berhasil dapat diproduksi dengan menggunakan tepung umbi dahlia dan jumlah penambahannya yang terbaik, dapat ditentukan.Effect of Substitution of Wheat Flour with Dahlia Tuber Flour and Concentration of Baking Powder on Physical Properties of Fiber Rich CookiesAbstractCookies are one of the snacks favored by wide range of consumers’s age. Usually, cookies made from wheat flour, which have high content of carbohydrate and fat but low content of fiber. In the present study, dahlia tuber flour was used to substitute wheat flour to produce fiber rich cookies. The effect of dahlia tuber flour was analyzed in the a varied baking powder addition. Dahlia tuber flour and wheat flour at ratio of 15:85, 30:70, and 45:55 (w/w); and baking powder concentration of 1–3% from total weight of the flour was usedas formula. Optimum formulation was obtained by Derringer’s Desirability Function, which compares the relation value of the physical properties of cookies made with dahlia tuber flour and control cookies which was made of wheat flour. The result showed that optimum formula to produce fiber rich cookies was obtained on the ratio of 30:70 and baking powder at concentration of 3%, with total desirability (D) value of 0.87. As conslusion, high fiber content cookies was succsessfully produced and the best dahlia tuber flour addition was determined optimally.

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Pseudomonas Isolates as Potential Biofungicides of Green Mold (Penicillium Digitatum) on Orange Fruit

International Journal of Fruit Science ◽

10.1080/15538362.2021.2018671 ◽

2022 ◽

Vol 22 (1) ◽

pp. 142-150

Author(s):

Redouan Qessaoui ◽

Mariem Zanzan ◽

Abdelhadi Ajerrar ◽

Hind Lahmyed ◽

Ahmed Boumair ◽

...

Keyword(s):

Penicillium Digitatum ◽

Green Mold ◽

Orange Fruit

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Objective: Antifungal activity of total ethanolic extract and fractions of Usnea varieties were proved against Aspergillus niger, Penicillium digitatum, and Rhizopus nigricans fungi. Methods: To perform the study of relative antifungal activity (AFR), flu

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2020.v13i10.38962 ◽

2020 ◽

pp. 171-174

Author(s):

DAYANNA CABRA GACHA ◽

LUIS POMBO OSPINA ◽

JANETH ARIAS PALACIOS ◽

OSCAR RODRÍGUEZ AGUIRRE

Keyword(s):

Antifungal Activity ◽

Aspergillus Niger ◽

Ethanolic Extract ◽

Penicillium Digitatum ◽

Total Extract ◽

Rhizopus Nigricans ◽

A Value

Objective: Antifungal activity of total ethanolic extract and fractions of Usnea varieties were proved against Aspergillus niger, Penicillium digitatum, and Rhizopus nigricans fungi. Methods: To perform the study of relative antifungal activity (AFR), fluconazole and ketoconazole were used as standards. The inhibition coefficient 50 (IC50) for each extract and the fractions was determined. Results: It was established that the highest activity was presented by the acetone fraction with a value of 58.53. In the study of antifungal activity, the fraction that presented the best activity against P. digitatum was ethanolic with a value of 44.33, while for R. nigricans was petrol extract, with a value of 75.35 and finally for A. niger was the total extract with a value of 35.48. Conclusions: Comparing the values obtained from the extract and the different fractions resulted in the dichloromethane fraction showing the best values.

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