Kinds Of Yeasts Research Articles

Study on Fermentation Technology and Flavor Substances of Strong Ale Beer

In this study, we selected three kinds of strong ale beer yeast, which were SafAle HA-18, Lallemand Saison and SafAle BE-134, for comparative brewing experiments. The comprehensive sensory evaluations were made by testing the physical and chemical indicators, flavor substances and antioxidant capacities, according to which a yeast suitable for the brewing of ale beer with high alcohol content was selected. We showed that there were some differences between the three kinds of yeast on fermentation performance. HA-18 performed the best on sugar lowering speed, yeast sedimentation, tolerance to alcohol and production of alcohol. Saison was outstanding on reproductive capacity and reduction speed of diacetyl. Although the fermentation speed was relatively close to HA-18, the sedimentation of Saison was poor. BE-134 had better yeast sedimentation, but the overall fermentation performance was average and the sensory quality of the finished beer was poor.

Effect of Different Levels of Cider, Baker Yeast and Hamei on Pineapple Cider

Cider is an alcoholic beverage that is produced when fruit juices are fermented; it is made using the same techniques as wine. Cider occupies a special place among its more well-known alcoholic siblings since it is brewed like wine but mostly served as beer. Eight treatments were reproduced three times in the CRD (Complete Randomized Design) format of the experiment. The pineapples were fermented by using two different kinds of yeast, baker yeast (Saccharomyces cerevisiae) and Hamei (Bacteria (Bacillus sp.), fungi (Aspergillus niger van Tiegh.) and the yeast (Saccharomyces cerevisiae) for 30 days. Longer fermentation times resulted in higher levels of alcohol, acidity, and sensory characteristics, but lower levels of total soluble solids, pH, and specific gravity were observed. Cider is a fermented product, produced from fruit juices, which increases juice’s shelf life. In this experiment, Hamei and baker yeast were used to make pineapple cider. Treatment T5 (Pineapple pieces (700 g) + Sugar (300g) + Hamei (0.5g) + Water (1L) produced the best cider among all the treatments in terms of alcohol content (7.00), pH (3.90) and total soluble solids (4.90 Brix).

Overview to Candidiasis

Candida is a kind of yeast, is a fungus that infects the body.Candidiasis is known as yeast contagion because the infecting agent is a yeast, Candida albicans. Candida albicans are the pathogens that are of much significance which are present everywhere and mostly reside along side plentiful bacteria near mouth, gastrointestinal tract and vagina. Hippocrates was the first person to describe candidiasis in 1849. Candidiasis of the mouth is termed as Thrush. Cutaneous candidiasis is a skin infection that occurs in parts of the skin that have very little ventilation and are rarely moist. Deep Candidiasis occurs when fungi infiltrate the body, enter the bloodstream, and spread throughout the body.Treatment methodology are different for each case. Natural prevention is mandatory to safe yourself from being a victim to disease

Effects of dietary Metschnikowia sp. GXUS03 on growth, immunity, gut microbiota and Streptococcus agalactiae resistance of Nile tilapia ( Oreochromis niloticus )

Probiotic feeding is a new strategy of healthy fish farming. To examine the effects of adding Torulaspora sp. GXUS02 and Metschnikowia sp. GXUS03 on the growth and immune parameters of Nile tilapia, a feeding trial was conducted in this study using a feed dose of 108 CFU/g to cultivate tilapia (100 ±15 g) for 8 weeks. The growth performance, serum parameters, intestinal microbiota and the anti-Streptococcus agalactiae ability of tilapia were used to evaluate the effects of the yeast supplemented group. The results reveal that both yeast diets could significantly improve the growth performance of tilapia by significantly increased the activities of protease and xylanase. Amongst the serum parameters, the lysozyme activity and the amount of complement C3 and C4 of tilapia fed with GXUS03 were significantly increased, and the ability to fight Streptococcus agalactiae was significantly increased (p < 0.05). Both yeast diets could change the intestinal microflora structure of tilapia. GXUS02 could significantly increase the amount of Sarcina and significantly decrease the amount of Microdiscus. In the intestinal microbiota of tilapia fed with GXUS03, Golenkinia-longispicula and LD29 were significantly increased, whilst the amount of Microdiscus was significantly decreased. In the analysis of intestinal microbiota diversity of tilapia fed with two yeast diets for 30 and 60 days, the stability of the intestinal microbiota of tilapia was better. In conclusion, the addition of two kinds of yeast had a good probiotic effect on tilapia culture, and GXUS03 exhibited the best probiotic effect in promoting the growth and immunity of tilapia.

IN VITRO EVALUATION OF ANTIFUNGAL ACTIVITY OF METHANOLIC ROOT EXTRACT OF SOLANUM SURATTENS AGAINST CANDIDA SPECIES

Candida is a kind of yeast that exists in the human body also and can cause infections if it grows in high amount. Solanum surattens also known as Solanum xanthocarpum is distributed to plains/lower hill region of India. The study was to assess invitro antifungal activity of methanolic root extract of Solanum surattens against Candida albicans, Candida glabrata, Candida krusei and Candida tropicali. Candidiasis is the most common infections. Based on the results, methanolic root extract of Solanum surattens might be a promising antifungal agent.

Construction of “fungi house”: an architectural approach for fabrication of carbon microspheres with superior capacitive and salt removal performance

Microsized carbon spheres with the refined interior structure are highly desired, while it is challenging to achieve controllability limited to synthetic strategy. Herein, a novel architectural approach is proposed for developing interior multi-chamber carbon microspheres (MCMs) with the help of a liquid template. We focus on building “rooms” in fruit wine yeast and yielding “fungi house,” which apply to other kinds of yeast. The size and number of the “room” can be controlled. To the best of our knowledge, such biomass-derived carbon spheres with defined interior structures have never been reported yet. When used as electrodes for supercapacitors and capacitive deionization, the exemplified MCM exhibits specific capacitance 339.31 F g−1 at 0.5 A g−1 and a salt adsorption capacity of 21.61 mg g−1 at 1.2 V, as well as excellent rate performance and cycle stability. Given the structure-dependent property, the architectural approach broadens the avenue to develop advanced materials.

Effect of Different Yeasts on the Quality of Navel Orange Wine

In order to select the best yeast for navel orange wine processing,six kinds of yeast,BV818,DV10,RV002,RV171,K1 and L2323 were used in Langfeng navel orange fermentation,separately. The physicochemical properties and flavor compounds were analyzed by UPLC and HS-SPME-GC-MS. Odor activity value(OAV)and principal component analysis were used for analysis and comprehensive evaluation. The results showed that the content of total flavonoids of K1,L2323,DV10 and RV002 fermented navel orange wine were higher than CK,and the post bitterness of limonoids of RV171,RV002,DV10 and K1 decreased significantly. A total of 86 aroma components were detected in 6 samples. The aroma components of each sample were 24~39,with the highest alcohol content,accounting for 49.44%~78.58% of the total aroma,and the most esters were OAV>1,which contributed the most to the aroma of the wine. Isoamyl alcohol,ethyl octanoate,phenylethyl acetate,ethyl decanoate were the main aroma substances of navel orange fruit wine,which make the characteristics of flower and fruit flavor outstanding. Five principal components were extracted by principal component analysis,the cumulative variance contribution rate was 93.99%,which could better reflect the comprehensive quality of navel orange wine. The ranking from high to low was DV10,RV171,RV002,L2323,BV818,K1. Combined with sensory evaluation,DV10 was the suitable yeast for navel orange wine brewing.

Investigation of the process of fermentation of recovered whey-malt mixtures

We report a study into the fermentation of the recovered whey-malt mixtures using the lactose-fermenting yeast and saccharomyces. The use of such mixtures for production of fermentation beverages using the appropriate kinds of yeast makes it possible to improve the biological value, compared to traditional (water-based) ones, through the nutrient components of milk whey and fermentation products. The result of the experiments is the selected optimum ratio of dry rye malt to milk whey for the preparation of mixtures. During our study, we took into consideration the chemical composition, solubility, and possible utilization of carbohydrates by different strains of yeast. It was revealed that the rational ratio of dry malt to whey is 1:2. During fermentation of wort, we observed the greatest increase in the yeast cells Kluyveromyces lactis 469, from 73 to 75.2 thousand/cm 3 , with the active phase of the process occurring from hour 4 to hour 16 of fermentation. Such indicators testify to the high fermentative activity to the carbohydrates of milk whey. Based on the amount of the accumulated ethyl alcohol and the content of reducing substances, we investigated the fermenting activity of other yeast strains. For fermentation, we used wort from the recovered dry mixture with the optimal ratio of components. It was revealed that the most active alcoholic fermentation took place in the wort fermented with the yeast Saccharomyces lactis 95. Less effective was the yeast Saccharomyces cerevisiae Р-87 in the above-specified environment. At a joint cultivation of lactose-fermenting yeast and saccharomyces the fermentation process is greatly enhanced. No synergism of microorganisms was observed. Based on the results from a gas chromatographic analysis, we identified the by-products of fermentation from the fermented whey-malt wort. It has been established that the concentrations of methyl acetate, (11.72±0.59) mg/dm 3 , and ethyl acetate, (92.17±4.61) mg/dm 3 , in the wort, fermented by the yeast Saccharomyces cerevisiae Р-87, are sufficient for creating a harmonious taste and aroma of the fermented beverage

Antimicrobial activity of yeasts against some pathogenic bacteria.

Aim:This study was designed to isolate and identify yeast species from milk and meat products, and to test their antimicrobial activity against some bacterial species.Materials and Methods:A total of 160 milk and meat products samples were collected from random sellers and super markets in New Damietta city, Damietta, Egypt. Samples were subjected to yeast isolation procedures and tested for its antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. In addition, all yeast species isolates were subjected to polymerase chain reaction (PCR) for detection of khs (kievitone hydratase) and pelA (pectate degrading enzyme)genes.Results:The recovery rate of yeasts from sausage was 20% (2/10) followed by kareish cheese, processed cheese, and butter 10% (1/10) each as well as raw milk 9% (9/100), and fruit yoghurt 30% (6/20). Different yeast species were recovered, namely, Candida kefyr (5 isolates), Saccharomyces cerevisiae (4 isolates), Candida intermedia (3 isolates), Candida tropicalis (2 isolates), Candida lusitaniae (2 isolates), and Candida krusei (1 isolate). khs gene was detected in all S. cerevisiae isolates, however, pelA gene was not detected in all identified yeast species. Antimicrobial activity of recovered yeasts against the selected bacterial species showed high activity with C. intermedia against S. aureus and E. coli, C. kefyr against E. coli, and C. lusitaniae against S. aureus. Moderate activities were obtained with C. tropicalis, C. lusitaniae, and S. cerevisiae against E. coli; meanwhile, all the tested yeasts revealed a very low antimicrobial activity against P. aeruginosa.Conclusion:The obtained results confirmed that some kinds of yeasts have the ability to produce antimicrobial compounds that could inhibit some pathogenic and spoilage bacteria and these antimicrobial activity of yeasts enables them to be one of the novel agents in controlling spoilage of food.

Cascade bioethanol productions from glucose and mannitol in saccharified kombu Laminariaceae by anaerobic and aerobic fermentations with two kinds of yeast

Cascade bioethanol productions from glucose and mannitol in saccharified kombu Laminariaceae by anaerobic and aerobic fermentations with two kinds of yeast

Kefir induces apoptosis and inhibits cell proliferation in human acute erythroleukemia.

Acute erythroleukemia is an uncommon subtype of acute myeloid leukemia which has been considered to be a subtype of AML with a worse prognosis. Intensive chemotherapy is the first line of treatment. In recent years, the effect of kefir on some malignancies has been experimented. Kefir is a kind of beverage, which obtained by incubation of kefir grains with raw milk. Kefir grains are a symbiotic complex of different kinds of yeasts and bacteria, especially lactic acid bacteria which gather in a mostly carbohydrate matrix, named kefiran. We investigated the effect of kefir on acute erythroleukemia cell line (KG-1) and peripheral blood mononuclear cells (PBMCs). The cell line and PBMCs were treated with different doses of kefir and milk and incubated for three different times. We used Polymixin B to block the lipopolysaccharide and NaOH (1mol/l) to neutralize the acidic media. Viability was detected by MTT assay. Apoptosis and necrosis were assessed by annexin-propidium iodide staining. Our results showed that kefir induced apoptosis and necrosis in KG-1 cell line. It was revealed that kefir decreased proliferation in erythroleukemia cell line. We did not observe a remarkable effect of kefir on PBMCs. Our study suggested that kefir may have potential to be an effective treatment for erythroleukemia.

A rapid microplate method for the proliferation assay of fungi and the antifungal susceptibility testing using the colorimetric microbial viability assay

A rapid microplate method for the proliferation assay of fungi and the antifungal susceptibility testing using the colorimetric microbial viability assay based on the reduction in a tetrazolium salt 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, monosodium salt (WST-8) with 2-methyl-1,4-napthoquinone as the electron mediator was developed. The proposed method was useful to measure the proliferation of 18 kinds of moulds and seven kinds of yeasts, including representative pathogens such as Aspergillus spp., Candida spp. and Cryptococcus spp. Linear relationships between the absorbance and viable fungal cell density were obtained for all fungi, suggesting that the absorbance change reflected the fungal proliferation. In addition, the minimum inhibitory concentrations (MICs) against a variety of different pathogenic moulds and yeasts for amphotericin B, itraconazole and 5-flucytosine were determined by susceptibility testing using the proposed method and compared with those obtained using the conventional broth microdilution method. There was an excellent agreement between the results obtained using the WST-8 colorimetric method and those obtained using the conventional Clinical and Laboratory Standard Institute method. The WST-8 colorimetric assay is a useful method for rapid determination of accurate MICs for a variety of different fungi. A rapid microplate method for the proliferation assay of fungi and the antifungal susceptibility testing using the colorimetric microbial viability assay based on reduction in a tetrazolium salt (WST-8) was developed. The WST-8 colorimetric method was useful to measure the proliferation of a variety of different fungi. In the antifungal susceptibility testing, there was a good agreement between the MICs determined after 24h using the WST-8 colorimetric method and those obtained after 48-96h using the broth microdilution method. The proposed method was superior to conventional methods in terms of its rapidity towards a variety of different fungi.

충남 예산군 신암면 일대 과수원의 과일과 꽃들로부터 효모의 분리 및 분포 특성

충청남도 예산군 신암면 일대 과수원들의 과일과 꽃에서 효모들을 분리한 후 이들의 26S rDNA의 D1/D2 부위의 염기서열을 결정한 다음 NCBI의 BLAST 데이터베이스에 등록되어 있는 효모들과의 분자생물학적 유연관계를 비교, 분석하여 동정하였다. 2013년 4월부터 10월 사이의 과일 19점으로부터 모두 25종의 효모들을 48균주 분리하였고 Pichia kluyveri, Hanseniaspora uvarum, Rhodotorula mucilaginosa, Torulaspora delbrueckii 등 4종의 효모 등이 많이 분포하고 있었다. 과수원 주위의 꽃 39점에서 48종의 효모 등을 108균주 분리하였고 이 중 Microstroma juglandis와 Pseudozyma aphidis가 가장 많이 분리되었다. Several kinds of yeasts from fruits and flowers of orchard in Yesan-gun of Chungcheongnam-do, Korea were isolated and identified by comparison of nucleotide sequences for PCR-amplified D1/D2 region of 26S rDNA using BLAST. Fourty eight yeast strains of twenty five species and one hundred eight yeast strains of fourty eight species were isolated from fruits and flowers of orchard in Sinam-myeon of Yesan-gun, Chungcheongnam-do, respectively. Among total one hundred fifty-six yeast strains, only sixteen species were overlapped from fruits and flowers.

A milliliter-scale yeast-based fuel cell with high performance

Microbial fuel cells are attracting attention as one of the systems for producing electrical energy from organic compounds. We used commercial baker's yeast (Saccharomyces cerevisiae) for a glucose fuel cell because the yeast is a safe organism and relatively high power can be generated in the system. In the present study, a milliliter (mL)-scale dual-chamber fuel cell was constructed for evaluating the power generated by a variety of yeasts and their mutants, and the optimum conditions for high performance were investigated. When carbon fiber bundles were used as an electrode in the fuel cell, high volumetric power density was obtained. The maximum power produced per volume of anode solution was 850W/m3 under optimum conditions. Furthermore, the power was examined using seven kinds of yeast. In Kluyveromyces marxianus, not only the power but also the power per consumed glucose was high. Moreover, it was suggested that xylose is available as fuel for the fuel cell. The fuel cell powered by K. marxianus may prove to be helpful for the effective utilization of woody biomass.

Preparation and Characteristics of Sugarcane Low Alcoholic Drink by Submerged Alcoholic Fermentation

A new low alcoholic drinks, was brewed from fresh sugarcane juice using different kinds of yeast, viz., wine yeast, Fali yeast and thermo-tolerant yeast by submerged alcoholic fermentation. The main characteristic parameters of fermented cane juice such as alcohol content, total sugars, total acids and reducing sugar were investigated during the process of alcoholic fermentation in order to evaluate the effect of yeasts on the quality of alcoholic drinks. The results showed that alcoholic fermentation period and the alcohol content of fermented cane juice ranged from 9 to 20 days and 2.8–4.8 %, respectively. With respect to sensory evaluation, the alcoholic drink obtained by using wine yeast was found suitable with yellow-brown colour, clear and brighter appearance, full wine and cane aromas and flavor. Its soft, mild, mellow and slightly sweet taste made it possible to be used as a beverage in dines. The results of this study concerning the use of sugarcane juice as one of raw materials could be promising for industrial fermentations of low alcoholic drinks production, and also provides a new approach to process sugarcane by-products.

Conserved and divergent features of kinetochores and spindle microtubule ends from five species

Interfaces between spindle microtubules and kinetochores were examined in diverse species by electron tomography and image analysis. Overall structures were conserved in a mammal, an alga, a nematode, and two kinds of yeasts; all lacked dense outer plates, and most kinetochore microtubule ends flared into curved protofilaments that were connected to chromatin by slender fibrils. Analyses of curvature on >8,500 protofilaments showed that all classes of spindle microtubules displayed some flaring protofilaments, including those growing in the anaphase interzone. Curved protofilaments on anaphase kinetochore microtubules were no more flared than their metaphase counterparts, but they were longer. Flaring protofilaments in budding yeasts were linked by fibrils to densities that resembled nucleosomes; these are probably the yeast kinetochores. Analogous densities in fission yeast were larger and less well-defined, but both yeasts showed ring- or partial ring-shaped structures girding their kinetochore microtubules. Flaring protofilaments linked to chromatin are well placed to exert force on chromosomes, assuring stable attachment and reliable anaphase segregation.

대전지역 야생화에서 분리한 미기록 효모 균주들의 보고

본 연구에서는 아직까지 한국 진균 학술지에 보고되어 있지 않은 6종의 새로운 효모들의 형태학적, 생리학적 특성에 대하여 보고한다. 이들 효모들은 한국의 대전시에 서식하고 있는 야생화들로부터 분리해서 ITS-2 또는 18S rDNA 염기서열의 분자생물학적 분석 방법을 이용 동정하였다. 이들 6종의 새로운 국내 미기록 효모들은 Kuraishia capsulate, Lodderomyces elongisporus, Pseudozyma antarctica, Starmerella bombicola으로 분리되었다. We report morphological and physiological characteristics of newly isolated six kinds of yeasts which are new in Korean mycoflora. The yeasts were isolated from wild flowers in Daejeon city, Korea and identified by molecular analysis of the amplified internal transcribed space rDNA sequence or partial 18S rDNA sequence. Species of isolates were identified as Kuraishia capsulate, Lodderomyces elongisporus, Pseudozyma antarctica, Starmerella bombicola.

Phenolic compounds and antioxidant activity in fermented rice (Oryza sativa) bran

Microbial pectinolytic enzymes are known to play a commercially important role in a number of industrial processes. Two kinds of yeast can be discerned regarding the production of enzymes. One group includes those which can produce enzymes in the absence of an inducer, and the other group comprises the yeasts that produce enzymes in the presence of an inducer. The objective of this study was to investigate the influence of pectic substances, glucose, pH, and temperature on the polygalacturonase activity by Kluyveromyces marxianus CCMB 322. The yeast was grown in a fermentation broth containing different concentrations of glucose and pectic substances. The polygalacturonase activity was determined by the DNS method, and the pH and temperature were optimized using a central composite experimental design. The polygalacturonase secreted by K. marxianus CCMB 322 was partially constitutive showing optimum pH and temperature of 7.36 and 70 °C, respectively, and maintained approximately 93% of its original activity for 50 minutes at 50 °C. Thermal stability of the polygalacturonase enzyme was studied at different temperatures (50, 60, 70, and 80 °C) and different incubation times (0, 10, 20, 30, 40, and 50 minutes). This study showed that glucose can influence the regulation of the synthesis of polygalacturonase.

Influence of carbon source, pH, and temperature on the polygalacturonase activity of Kluyveromyces marxianus CCMB 322

Microbial pectinolytic enzymes are known to play a commercially important role in a number of industrial processes. Two kinds of yeast can be discerned regarding the production of enzymes. One group includes those which can produce enzymes in the absence of an inducer, and the other group comprises the yeasts that produce enzymes in the presence of an inducer. The objective of this study was to investigate the influence of pectic substances, glucose, pH, and temperature on the polygalacturonase activity by Kluyveromyces marxianus CCMB 322. The yeast was grown in a fermentation broth containing different concentrations of glucose and pectic substances. The polygalacturonase activity was determined by the DNS method, and the pH and temperature were optimized using a central composite experimental design. The polygalacturonase secreted by K. marxianus CCMB 322 was partially constitutive showing optimum pH and temperature of 7.36 and 70 °C, respectively, and maintained approximately 93% of its original activity for 50 minutes at 50 °C. Thermal stability of the polygalacturonase enzyme was studied at different temperatures (50, 60, 70, and 80 °C) and different incubation times (0, 10, 20, 30, 40, and 50 minutes). This study showed that glucose can influence the regulation of the synthesis of polygalacturonase.

White Wine Making using Campbell Early Grapes with different Kinds of Yeasts

White Wine Making using Campbell Early Grapes with different Kinds of Yeasts