• Title/Summary/Keyword: alcohol-tolerance

Search Result 72, Processing Time 0.027 seconds

Screening Wild Yeast Strains for Alcohol Fermentation from Various Fruits

  • Lee, Yeon-Ju;Choi, Yu-Ri;Lee, So-Young;Park, Jong-Tae;Shim, Jae-Hoon;Park, Kwan-Hwa;Kim, Jung-Wan
    • Mycobiology
    • /
    • v.39 no.1
    • /
    • pp.33-39
    • /
    • 2011
  • Wild yeasts on the surface of various fruits including grapes were surveyed to obtain yeast strains suitable for fermenting a novel wine with higher alcohol content and supplemented with rice starch. We considered selected characteristics, such as tolerance to alcohol and osmotic pressure, capability of utilizing maltose, and starch hydrolysis. Among 637 putative yeast isolates, 115 strains exhibiting better growth in yeast-peptone-dextrose broth containing 30% dextrose, 7% alcohol, or 2% maltose were selected, as well as five ${\alpha}$-amylase producers. Nucleotide sequence analysis of the 26S rDNA gene classified the strains into 13 species belonging to five genera; Pichia anomala was the most prevalent (41.7%), followed by Wickerhamomyces anomalus (19.2%), P. guilliermondii (15%), Candida spp. (5.8%), Kodamaea ohmeri (2.5%), and Metschnikowia spp. (2.5%). All of the ${\alpha}$-amylase producers were Aureobasidium pullulans. Only one isolate (NK28) was identified as Saccharomyces cerevisiae. NK28 had all of the desired properties for the purpose of this study, except ${\alpha}$-amylase production, and fermented alcohol better than commercial wine yeasts.

Screening and Characterization of the High-Alcohol Producing Saccharornyces cerevisiae Dl (고농도 알콜발효효모 Saccharomyces cerevisiae D1의 분리 및 특성)

  • 양지영;박경호;백운화;유주현
    • Microbiology and Biotechnology Letters
    • /
    • v.18 no.5
    • /
    • pp.511-516
    • /
    • 1990
  • A high-alcohol producing yeast strain had sugar and alcohol tolerance was isolated from soil and identified as Saccharomyces cerevisiae Dl according to the Lodder's yeast taxonomic studies. On investigation of the characteristics of the strain, it could grow in 60% glucose, within 15% ethanol and in the YPD medium containing 2.0 mM copper. It had 39.1% the inhibition rate of fermentation efficiency and 8% viability after 2 days in the YPD medium containing 15% ethanol. Its optimum initial pH, growth temperature, initial glucose concentration for the production of alcohol showed pH 4.5, $30^{\circ}C$, and 30%, respectively. Saa:hwomyce8 mvisiae Dl produced 14.0% (wlv) alcohol when incubated at $30^{\circ}C$, with orbital shaking 150 rpm for 72 h in a medium (pH 4.5) containing 30% (wfv) glucose.

  • PDF

Characteristics of wild yeast isolated from non-sterilized Makgeolli in Korea (국내 생막걸리에서 분리한 야생 효모의 특성)

  • Jung, Su Ji;Yeo, Soo-Hwan;Mun, Ji-Young;Choi, Han-Seok;Baek, Seong Yeol
    • Food Science and Preservation
    • /
    • v.24 no.7
    • /
    • pp.1043-1051
    • /
    • 2017
  • Wild yeasts were isolated from domestic non-sterilized Makgeolli and their fermentation characteristics were analyzed to select the best fermentation seed culture. A total of 65 yeast strains isolated yeasts from non-sterilized Makgeolli and Nuruk. In order to select fermentable strains, hydrogen sulfide, $CO_2$ production ability, alcohol tolerance and aroma component production ability were analyzed. To screen the aromatic strains of isolates, media containing cerulenin, 5,5,5-trifluor-DL-leucine (TFL) and API ZYM kit were used. There were 36 strains resistance to cerulenin and all strains produced esterase and demonstrated tolerance against TFL. Hydrogen sulfide, which could degrade the quality of the fermented beverage, was not produced in 34 yeast. The correlation between alcohol tolerance of yeast and carbon dioxide production was analyzed by principal component analysis. YM22, YM31, YM32 and YM37 produced a total of 0.14-0.18 g/72 h of $CO_2$ indicating high fermentability. Alcohol tolerance was measured by alcohol concentration. YM32, YM37 yeast had 20% alcohol tolerance. As a result, alcohol and flavor characteristics of wild yeast isolated from non-sterilized Makgeolli were analyzed and it was confirmed that yeast was suitable for the production of alcohol.

Comparison of Cleansing Regimes for Efficacy and Comfort of Iontophoretic Transdermal Lidocaine Delivery (세정방법에 따른 국소마취제 이온도입의 효율과 편안감 비교)

  • Jeong, Myung-A;Song, In-Yong;Lee, Jae-Hyoung
    • The Journal of Korean Physical Therapy
    • /
    • v.18 no.4
    • /
    • pp.41-50
    • /
    • 2006
  • Purpose: The purpose of this study was to determined that the efficacy and comfort of iontophoretic transdermal delivery of lidocaine by comparison of local anesthetic duration, sensory threshold, pain threshold and pain tolerance levels according to four different cleansing regimes. Methods: Forty healthy volunteers were randomly assigned to four groups; oil cleansing group, lotion cleansing group, solution cleansing group and alcohol cleansing group. All subjects were received lidocaine iontophoresis on the forearm using direct current with 4 mA for 10 minutes. All subjects were measured the duration of local anesthesia after lidocaine iontophoresis, also evaluated the sensory threshold, pain threshold and pain tolerance level during iontophoresis. For comparisons of the efficacy and the sensory characteristics of iontophoresis within the groups, an one-way ANOVA was used. Results: The duration of local anesthesia were found significant difference between groups (p<0.001). The anesthetic duration in solution and alcohol cleansing groups were significantly longer than oil and lotion cleansing group by post hoc (p<0.05). Statistically significant difference were noted in respect to all sensory characteristics such as sensory threshold, pain threshold and pain tolerance between groups (p<0.001). The sensory threshold in solution and alcohol cleansing group were significantly lower than oil and lotion cleansing group by post hoc using Duncan multiple range test (p<0.05). The pain threshold and pain tolerance in solution and alcohol cleansing group were significantly higher than oil and lotion cleansing group by post hoc (p<0.05). Conclusion: These results demonstrated that cleansing regimes have affected the efficacy and discomfort of iontophoretic transdermal delivery of lidocaine. These findings indicate that cleansing agents without oil ingredient contributed to more comfort, and more successful achievement of the iontophoretic transdermal delivery.

  • PDF

The Conditions Affecting Ethanol Tolerance of Yeast strains in Alcohol Fermantation - Study on the Fermantation Temperature and Substrate Type (알콜발효에서 효모의 에탄올 내성 조건-발효온도와 기질종류에 대한 연구)

  • 김형진;유연우
    • KSBB Journal
    • /
    • v.4 no.2
    • /
    • pp.167-171
    • /
    • 1989
  • The alcohol fermentation using glucose and lactose was carried out to study the effect of fermentation temperature on the ethanol tolerance of Saccharomyces cerevisiae STV89 and Kluyveromyces fragilis CBS397. The maximum specific growth rate and ethanol production rate were increased up to 35$^{\circ}C$ with the fermentation temperature, although maximum ethanol and cell concentration were decreased by increasing the fermentation temperature. The cell viability was also improved by lowering the fermentation temperature. Under the experimental conditions, the best ethanol tolerance of yeast strains was obtain at $25^{\circ}C$. The ethanol tolerance of S. cerevisiae is better than that of K. fragilis at the same fermentation condition. With respect to the carbon source, glucose is found to be more favorable for ethanol tolerance of K. fragilis than lactos.

  • PDF

Isolation and characterization of Bradh1 gene encoding alcohol dehydrogenase from Chinese cabbage (Brassica rapa)

  • Abdula, Sailila E.;Lee, Hye-Jung;Melgar, Reneeliza J.;Sun, Mingmao;Kang, Kwon-Kyoo;Cho, Yong-Gu
    • Journal of Plant Biotechnology
    • /
    • v.38 no.1
    • /
    • pp.77-86
    • /
    • 2011
  • Alcohol dehydrogenase (E.C.1.1.1.1) is an enzyme present in higher plants involved in the anaerobic fermentation pathway that catalyzes the reduction of pyruvate to ethanol, resulting in continuous $NAD^+$ regeneration. It also plays an important role in many plant developments including tolerance to anoxia condition. Here, a cDNA clone encoding alcohol dehydrogenase (ADH) was isolated from Chinese cabbage (Brassica rapa) seedlings. The gene named Bradh1 had a total length of 1,326 bp that contains a single open reading frame of 1,140 bp. The predicted protein consists of 379 amino acid residues with a calculated molecular mass of 41.17 kDa. Expression pattern analysis revealed a tissue-specific expressing gene in different tissues and strongly expressed in the shoot, roots and seeds of Chinese cabbage. Agrobacterium transformation of full-length cDNA Bradh1 into rice Gopumbyeo showed high efficiency. Furthermore, induction of ADH in transgenic rice enhanced tolerance to anaerobiosis stresses and elevated mRNA transcripts. The overexpression of Bradh1 in rice increases germination under anaerobiosis stresses, implying the possibility of developing new varieties suited for direct seeding or flood-prone rice field.

The Nutritional Status of Middle Aged Korean Men Exhibiting Impaired Glucose Tolerance and Their Blood Lipid Profile (내당능장애 가능성이 있는 중년 남성의 신체적 특성, 영양소 섭취상태 및 혈중 지질농도 양상)

  • 양윤정;김진옥
    • Journal of Nutrition and Health
    • /
    • v.33 no.1
    • /
    • pp.59-67
    • /
    • 2000
  • The objective of this study was to investigate nutritional status of middle aged Korean men exhibiting impaired glucose tolerance (IGT) and identify the risk factors related to IGT Data were collected from 163 men with a fasting blood glucose level from 115 to 139mg/dl(high blood glucose group: HBG) and 170 men with a normal fasting blood glucose level(control) aged from 40 to 59 years in both groups. Weight, body mass index(BMI) and percent body fat were significantly higher in high blood glucose(HBG) group than those of control group. Age, weight, BMI, percent body fat were positively related to blood glucose. There were no differences in exercise, smoking and family history of diabetes between two groups. Frequency of fat eating and overeating of HBG were higher than those of control group but frequency of sweet snacks intake of HBG was lower than that of control group. There was no difference in daily total energy intake in two groups. Total and supper energy intakes were positively associated with blood glucose. Percent energy intake of alcohol was significantly higher in HBG group and positively related to blood glucose, however there were no difference in daily intake of nutrients in two groups. Alcohol intake was positively related to BMI, but after adjusting BMI, there was no correlation between alcohol intake and blood glucose. Serum total cholesterol and triglyceride were significantly higher in HBG group than those of control group. Serum total cholesterol i,nd triglyceride were positively related to blood glucose and high density lipoprotein cholesterol was negatively associated with blood glucose. After adjusting BMI, serum triglyceride was positively related to blood glucose. In conclusion, weight, BMI, percent body fat and blood total cholesterol, low density lipoprotein cholesterol and triglyceride levels were positively related to blood glucose level of middle aged Korean men exhibiting impaired glucose tolerance. Their eating habits exhibited higher frequency of overeating, fast eating, high energy intakes of supper. (Korean J Nutrition 33(1) : 59-67, 2000)

  • PDF

Alcohol and Sleep (수면과 알코올)

  • Park, Doo-Heum;Yu, Jae-Hak;Ryu, Seung-Ho
    • Sleep Medicine and Psychophysiology
    • /
    • v.13 no.1
    • /
    • pp.5-10
    • /
    • 2006
  • Alcohol has extensive effects on sleep and daytime sleepiness. Alcohol has a sleep inducing effect and the effect of increased non-REM sleep and suppressed REM sleep during the first half portion of night sleep, but alcohol induces the effect of decreased non-REM sleep and increased light sleep and frequent awakenings and REM rebound during the second half portion of night sleep. Alcohol provokes chronobiological change such as the changes of amplitude or the phase shifts of hormones or core body temperature. The sleep disruption resulting from alcohol drinking may lead to daytime fatigue and sleepiness. The elderly are at particular in the increased risk of alcohol-related sleep disorders because they achieve higher levels of alcohol in the blood and brain than do younger adults after consuming an equivalent dose. Bedtime alcohol consumption among older adults may lead to unsteadiness if walking is attempted during the night, with increased risk of falls and injuries. Continued alcohol use for sleep induction often induces aggravation of insomnia, alcoholism or sleep related breathing disorders such as obstructive sleep apnea. Alcohol should not be used as substitution of sleep pill because of the dependence and tolerance for sleep inducing effect, and the sleep disruption produced by alcohol withdrawal.

  • PDF

Isolation of Alcohol-tolerant Amylolytic Saccharomyces cerevisiae and Its Application to Alcohol Fermentation

  • Jung, He-Kyoung;Park, Chi-Duck;Bae, Dong-Ho;Hong, Joo-Heon
    • Food Science and Biotechnology
    • /
    • v.17 no.6
    • /
    • pp.1160-1164
    • /
    • 2008
  • An novel amylolytic yeast, Saccharomyces cerevisiae HA 27, isolated from nuruk, displayed resistance against high sugar (50% glucose) and alcohol (15%). Maximal production of amylolytic enzyme by S. cerevisiae HA 27 was achieved on 9 days of cultivation at the optimal temperature $20^{\circ}C$ and pH 6.0. The activity of amylolytic enzyme produced by S. cerevisiae HA 27 was stable, even at $70^{\circ}C$, and over a broad pH range (4.0-11.0). Also, the amylolytic enzyme of S. cerevisiae HA 27 showed optimal activity in pH 5.0 at $50^{\circ}C$. S. cerevisiae HA 27 exhibited 6.2%(v/v) alcohol fermentation ability using starch as a carbon source.

Effect of Oxygen and Unsaturated Fatty Acids on the Ethanol Tolerance of Yeast Strains

  • Ryu, Yeon-Woo;Jang, Heang-Wook
    • Journal of Microbiology and Biotechnology
    • /
    • v.1 no.1
    • /
    • pp.6-11
    • /
    • 1991
  • This study deals with investigation of the ethanol tolerance of yeast strains with respect to fatty acid composition and intracelluar ethanol concentration during alcohol fermentation. The cell viabilities and fermentation abilities of Saccharomyces cerevisiae and Kluyveromyces fragilis were improved by aeration and addition of unsaturated fatty acids into growth medium. Aeration decreases the accumulation of ethanol, while increases unsaturated fatty acid contents inside yeast cells. Thus it was found that oxygen and unsaturated fatty acids play decisive roles in the increase of ethanol tolerance of yeasts.

  • PDF