• KSBB Journal
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• 제14권6호
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• pp.747-753
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• 1999

Microbial surfactants are more effective and environmentally friendly than many synthetic surfactants. Sophorolipid, a glycolipid type microbial surfactant, is produced from C. bombiocola. Cultivation techniques to increase the productivity have been developed using various carbon sources and reactor setup, reaching its concentration upto 100-300 g/L. Due to its high productivity and non-toxicity, sophorolipid became one of the most promising alternative to synthetic surfactants. Fermentative production of sophorolipid depends primarily on the carbon sources, such as glucose and vegetable oils, and nitrogen sources. Chemical modification of the sophorolipid produces various derivative with different physical properties including hydrophile-liphophilie balance(HLB), emulsion formation, surface tension and dispersing ability. Commercial potentials of sophorolipid in the cosmetic, health care and environment clean-up industries have been discussed.

• Journal of Microbiology and Biotechnology
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• 제29권8호
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• pp.1240-1247
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• 2019

This study was conducted to examine the inactivation effect of the combined treatment of high hydrostatic pressure (HHP; 400 MPa for 1, 3, and 5 min) and cationic surfactant washing (0.05% benzethonium chloride, BEC) against Listeria monocytogenes inoculated on fresh-cut broccoli (FCB). Washing with BEC at concentrations exceeding 0.05% resulted in 2.3 log-reduction of L. monocytogenes counts on FCB, whereas HHP treatment had approximately 5.5-5.6 log-reductions regardless of the treatment time. Scanning electron microscopy corroborated microbial enumeration, revealing that the combined treatment was more effective in removing L. monocytogenes from FCB than individual treatment with HHP or BEC. Color and total glucosinolate content were maintained after the combined treatment, although the hardness of the FCB slightly decreased. The results clearly suggest that the combined treatment of HHP and BEC washing has potential value as a new sanitization method to improve the microbial safety of FCB.

• Journal of Animal Science and Technology
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• 제49권5호
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• pp.647-656
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• 2007

반추동물의 생산효율을 향상시킬 목적으로 반추위 환경을 조절하려는 노력들이 수십년간 지속되어 오면서 그동안 주로 사료급여 및 사양관리 시스템 개발(NRC, 2001)이 근간을 이루어 왔으나, 최근에는 유전공학, 효소공학, 생물공학, 미생물공학, 천연물화학 등의 발전으로 식물추출물, 항생제, 미생물제제, 계면활성제 등 다양한 분야에서 연구가 진행되고 있다 (Yang과 Russell, 1993; 이 등, 1997; Lee 등, 2003; Lee와 Ha, 2003; Busquet 등, 2006). 그 중, 계면활성제인 surfactant는 미생물 세포막 표면에 부착하여 미생물에 대한 산소공급을 차단함으로써 호기성 미생물 성장을 감소시키며 (Hulme와 Stranks, 1970), 세포내, 외의 효소를 유리시켜 효소기능 및 분비를 촉진 하는 것 (Reese와 Maguire, 1969; Munn 등, 1983; Yazdi 등, 1990)으로 알려져 있다. 이러한 surfactant의 작용원리를 이용하여 반추위내 혐기성 발효를 촉진시키기 위한 제제로서 그 가능성이 높이 평가되어 왔는데, 지금까지 반추위 발효 조절 기능이 밝혀진 계면활성제는 비이온성으로서 반추동물의 소화율과 생산성에 기여할 수 있는 제제로서 인정받고 있다. 계면활성제를 이용한 일련의 시험 중, 앞서 수행한 비이온성 계면활성제와 양쪽 이온성(+/－) 계면활성제를 이용한 시험에서 비이온성 계면활성제는 in vitro 반추위 발효양상에 매우 긍정적인 결과를 얻었으나 양쪽 이온성(+/－) 계면활성제는 반추위 미생물에 오히려 독성으로서 작용하는 결과를 얻었다(De Oude, 1992). 또한 양(+)이온성과 음(－)이온성 계면활성제에 대한 국내의 연구가 전무한 사항이라 참고 자료를 찾을 수가 없었다. 따라서 본 시험은 일반적으로 많이 사용하는 양(+)이온 또는 음(－)이온성을 띄는 계면활성제를 선발하여 반추위 발효 성상 및 미생물 합성에 어떠한 영향을 미치는지를 규명해 보고자 실시하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권12호
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• pp.1690-1698
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• 2011

Feedlot and in vitro ruminal experiments were conducted to assess the effects of saponin-containing surfactant applied during tempering of barley grain on cattle growth performance and on ruminal fermentation. In the feedlot experiment, treatments with three barley grain/barley silage based diets were prepared using barley grain at 7.7% moisture (dry, D), after tempering to 18% moisture (M), or after tempering with a saponin-based surfactant included at 60 ml/t (MS). Each treatment was rolled at settings determined previously to yield optimally processed barley. A total of 180 newly weaned British${\times}$Charolais steers were fed three diets in 18 pens for a 63-d backgrounding period and 91-d finishing period to determine feed intake, growth rate and feed efficiency. Cattle were slaughtered at the end of the experiment to measure the carcass characteristics. Tempering reduced (p<0.001) volume weight and processing index, but processing characteristics were similar between MS and M. Tempering increased (p<0.05) growth during backgrounding only, compared with D, but did not affect feed intake in either phase. During backgrounding, feed efficiency was improved with tempering, but during finishing and overall this response was only observed with the surfactant. Tempering did not affect carcass weight, fat content or meat yield. Surfactant doubled the proportion of carcasses grading AAA. In the in vitro experiment, barley (500 mg; ground to <1.0 mm or steam-rolled) was incubated in buffered ruminal fluid (40 ml) without or with surfactant up to 20 ${\mu}l/g$ DM substrate for 24 h. Surfactant increased (p<0.05) apparent DM disappearance and starch digestibility but reduced productions of gas and the volatile fatty acid and acetate:propionate ratio, irrespective of barley particle size. Compared with feeding diets prepared with non-tempered barley, tempering with surfactant increased the feed efficiency of feedlot steers. This may have arisen from alteration in processing characteristics of barley grain by surfactant rather than its direct effect on rumen microbial fermentation.

• 한국식품위생안전성학회지
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• 제8권4호
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• pp.241-249
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• 1993

This study was performed to investigate the remainity of synthetic surfactant (LAS) by HPLC and the microbial contamination on stainless steel dishes. For the maintenance and the improvement of school lunch program's safety, the remainity of synthetic surfactants (LAS) on stainless steel dishes washed with auto dishwasher was investigated by HPLC, and the microbial contamination on same dishes was surveyed. The results were as follows: (1) The remainity of synthetic surfactant (LAS) a) The residue of LAS was very small because of the repeated washing of dishes by strong pressurized water. b) The remainity range of LAS on stainless steel dishes was 2.1~7.2 $\mu\textrm{g}$/dish. The remainity of general surfactants was higher in cold water then warm water. The amount of residual general surfatants was 5.95 $\mu\textrm{g}$/dish in cold water, and 2.95 $\mu\textrm{g}$/dish in warm water. There was no difference of the remainity of special surfactants by water temperature. The amount of residual surfactants was 3.9 $\mu\textrm{g}$/dish. c) There was no difference of residue amount by washing times. (2) The microbial contamination after washing with general surfactants. 1) The mean MPN of E. coli was 203(53~345) on 1 hr, 19(6~28) on 2 hrs, in cold water, and 1100(only 1 dish of 1 school) on 1 hr, 24(6~42) on 2hrs. 2) After washing with general surgactants the mean of contamination by general microbials was 956(25~2300)on 1 hr, 694(45~2500) on 2 hrs. in cold water and 803(5~2300) on 1 hr, 671(5~2500)on 2 hrs. After washing with special surfactants the mean of contamination by general microbials was 788(136~2900) on 1 hr, 1122(15~3000) on 2 hrs, in cold water and 537(5~2000) on 1 hr, 88(15~150) on 2 hrs in warm water. (3) Like the results of this study, the good washing methods of stainless steel dishes for school luch program were as follows. First, for washing stainless steel dishes, the use of special surfactants was recommended at 30~4$0^{\circ}C$ water. Second, at 7$0^{\circ}C$ water, the rinsing of dishes was recommended. Third, the final rinsing at 8$0^{\circ}C$ combined with simple disinfection and dry was recommended.

• Journal of Microbiology and Biotechnology
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• 제28권4호
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• pp.503-509
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• 2018

Endive is widely consumed in a fresh-cut form owing to its rich nutritional content. However, fresh-cut vegetables are susceptible to contamination by pathogenic bacteria. This study investigated the antibacterial activities of the combined treatment of cinnamon leaf oil emulsion containing cetylpyridinium chloride or benzalkonium chloride (CLC and CLB, respectively) as a cationic surfactant and ultrasound (US) against Listeria monocytogenes and Escherichia coli O157:H7 on endive. The combined treatment of CLC or CLB with US reduced the population of L. monocytogenes by 1.58 and 1.47 log colony forming units (CFU)/g, respectively, and that of E. coli O157:H7 by 1.60 and 1.46 log CFU/g, respectively, as compared with water washing treatment. The reduction levels of both pathogens were higher than those observed with 0.2 mg/ml sodium hypochlorite. In addition, the combined treatment showed no effect on the quality of the fresh-cut endive (FCE). In particular, the degree of browning in FCE was less for the treatment group than for the control and water washing treatment groups. Thus, cationic surfactant-based cinnamon leaf oil emulsions combined with US may be an effective washing treatment for the microbial safety of FCE.

• KSBB Journal
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• 제10권2호
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• pp.113-118
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• 1995

P. spiculispoTum으로부터 생산되는 미생물계변활 성제인 S-acid의 전구체인 O-acid 생산에 영향을 주는 인자들을 검토하고 포도탕 유가배양을 통해 최 척생산조건을 조사하였다. 탄소원으로 oil 등은 별 영향을 마치지 않았고 포도당이 O-acid 생산에 적절 한 탄소원이였으며 무기질소원으로는 $NH_4NO_3$가 높은 O-acid 생산량을 보였다. 미량원소인 $CaCl_2, FeSO_4$등의 첨가에 의해 약 20% 정도의 O-acid가 증가되었으며 용존산소는 포화에 가깡게 유지한 경 우 생산량은 40% 증가되였다. 배양 중 포도당농도는 $50g/\ell$로 유지하는 것이 최적이었으며 Fermentor 에서 포도당의 유가식공급에 의한 경우, 회분식에 비하여 약 60% 의 O-acid 생산증가를 보였다.

• Journal of Microbiology and Biotechnology
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• 제22권3호
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• pp.283-291
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• 2012

Bioremediation efforts often rely on the application of surfactants to enhance hydrocarbon bioavailability. However, synthetic surfactants can sometimes be toxic to degrading microorganisms, thus reducing the clearance rate of the pollutant. Therefore, surfactant-resistant bacteria can be an important tool for bioremediation efforts of hydrophobic pollutants, circumventing the toxicity of synthetic surfactants that often delay microbial bioremediation of these contaminants. In this study, we screened a natural surfactant-rich compartment, the estuarine surface microlayer (SML), for cultivable surfactant-resistant bacteria using selective cultures of sodium dodecyl sulfate (SDS) and cetyl trimethylammonium bromide (CTAB). Resistance to surfactants was evaluated by colony counts in solid media amended with critical micelle concentrations (CMC) of either surfactants, in comparison with non-amended controls. Selective cultures for surfactant-resistant bacteria were prepared in mineral medium also containing CMC concentrations of either CTAB or SDS. The surfactantresistant isolates obtained were tested by PCR for the Pseudomonas genus marker gacA gene and for the naphthalene-dioxygenase-encoding gene ndo. Isolates were also screened for biosurfactant production by the atomized oil assay. A high proportion of culturable bacterioneuston was tolerant to CMC concentrations of SDS or CTAB. The gacA-targeted PCR revealed that 64% of the isolates were Pseudomonads. Biosurfactant production in solid medium was detected in 9.4% of tested isolates, all affiliated with genus Pseudomonas. This study shows that the SML is a potential source of surfactant-resistant and biosurfactant-producing bacteria in which Pseudomonads emerge as a relevant group.

• Asian-Australasian Journal of Animal Sciences
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• 제16권5호
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• pp.672-676
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• 2003

Effect of a surfactant Tween 80 on the bacterial growth in the rumen was examined on the in vitro pure cultures of Streptococcus bovis, Selenomonas ruminantium, Butyrivibrio fibrisolvens, Prevotella ruminicola, Megasphaera elsidenni, Fibrobacta succinogenes, Ruminanococcus albus and Ruminococcus flavefaciens. Dry matter degradability (DMD), concentrations and compositions of volatile fatty acids (VFA), and the most probable number (MPN) of cellulolytic bacteria and total number of bacteria in the presence of Tween 80 were also examined on the in vitro rumen mixed culture either with barley grain or orchardgrass hay. The growth of S. bovis, S. ruminantium, B. fibrisolvens, P. ruminicola, M. elsidenni and F. succinogenes were significantly higher (p<0.05) at over 0.05% concentrations of Tween 80 than those of the control cultures, while was not changed with R. albus and R. flavefaciens. With rumen mixed culture the DMD of barley grain and orchardgrass hay was significantly higher (p<0.05) at a 0.2% concentration of Tween 80 than the control, being reflected in the significantly higher (p<0.05) VFA production (mmol $g^{-1}$DDM) with orchardgrass hay. The higher (p<0.05) ratio of propionate to acetate at a 0.2% concentration of Tween 80 was also observed with orchardgrass hay, showing a similar trend with barley grain. No changes in the total bacterial number and MPN of cellulolytic bacteria were observed.

• Environmental Analysis Health and Toxicology
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• 제7권3_4호
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• pp.69-79
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• 1992

Recently, concerns of water pollution and health risks caused by synthetic detergents have emerged, as the use of various detergents has increased It has been suggested that some surfactants are cocarcinogens. The surfactants tested were linear alkylbenzene sulfonate, sodium lauryl sulfate, polyoxyethylene sorbitan monooleat (tween 80), and the mutagens were 1-nitropyrene, N -methyl- N'-nitro-N -nitrosoguanidine, benzo (a) pyrene, and aflatoxin B$_1$. This study was undertaken to investigate the effects of surfactants on the activity of mytagens using the Ames mutagenic assay with Salmonella typhimurium TA98, TA100. The results were summarized as follows: 1. The surfactants have no mutagenic activity of themselves. 2. Higher doses of surfactants than 100 $\mu\textrm{g}$/plate reduced the number of revertants. It is assumed that the reduction would inhibited cell growth. 3. When the comutagenic ratio is defined as the ratio between mutagenic activity itself and the activity with mutagen and surfactant (drinking water quality standard), LAS showed the comutagenic ratio 0.86-1.17 and SLS 0.74-1.10 as well. According to the comparisons, it could not be recognised for the comutagenicity of drinking water quality standard of surfactant. 4. As increasing the amount of mutagens, the designated amount of surfactant did not affected the mutagen's activity statistically. From the above result, syunthetic surfactants do not present mutagenicity and comutagenicity in the microbial assay.