Characterization of exopolysaccharide-producing lactic acid bacteria from Taiwanese ropy fermented milk and their application in low-fat fermented milk

Ng Ker-Sin,Chang Yu-Chun,Chen Yen-Po,Lo Ya-Hsuan,Wang Sheng-Yao,Chen Ming-Ju 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.2

Objective: The aim of this study was to characterize the exopolysaccharides (EPS)-producing lactic acid bacteria from Taiwanese ropy fermented milk (TRFM) for developing a clean label low-fat fermented milk. Methods: Potential isolates from TRFM were selected based on the Gram staining test and observation of turbid suspension in the culture broth. Random amplified polymorphic DNA-polymerase chain reaction, 16S rRNA gene sequencing, and API CHL 50 test were used for strain identification. After evaluation of EPS concentration, target strains were introduced to low-fat milk fermentation for 24 h. Fermentation characters were checked: pH value, acidity, viable count, syneresis, and viscosity. Sensory evaluation of fermented products was carried out by 30 volunteers, while the storage test was performed for 21 days at 4°C. Results: Two EPS-producing strains (APL15 and APL16) were isolated from TRFM and identified as Lactococcus (Lc.) lactis subsp. cremoris. Their EPS concentrations in glucose and lactose media were higher than other published strains of Lc. lactis subsp. cremoris. Low-fat fermented milk separately prepared with APL15 and APL16 reached pH 4.3 and acidity 0.8% with a viable count of 9 log colony-forming units/mL. The physical properties of both products were superior to the control yogurt, showing significant improvements in syneresis and viscosity (p<0.05). Our low-fat products had appropriate sensory scores in appearance and texture according to sensory evaluation. Although decreasing viable cells of strains during the 21-day storage test, low-fat fermented milk made by APL15 exhibited stable physicochemical properties, including pH value, acidity, syneresis and sufficient viable cells throughout the storage period. Conclusion: This study demonstrated that Lc. lactis subsp. cremoris APL15 isolated from TRFM had good fermentation abilities to produce low-fat fermented milk. These data indicate that EPS-producing lactic acid bacteria have great potential to act as natural food stabilizers for low-fat fermented milk. Objective: The aim of this study was to characterize the exopolysaccharides (EPS)-producing lactic acid bacteria from Taiwanese ropy fermented milk (TRFM) for developing a clean label low-fat fermented milk.Methods: Potential isolates from TRFM were selected based on the Gram staining test and observation of turbid suspension in the culture broth. Random amplified polymorphic DNA-polymerase chain reaction, 16S rRNA gene sequencing, and API CHL 50 test were used for strain identification. After evaluation of EPS concentration, target strains were introduced to low-fat milk fermentation for 24 h. Fermentation characters were checked: pH value, acidity, viable count, syneresis, and viscosity. Sensory evaluation of fermented products was carried out by 30 volunteers, while the storage test was performed for 21 days at 4°C.Results: Two EPS-producing strains (APL15 and APL16) were isolated from TRFM and identified as Lactococcus (Lc.) lactis subsp. cremoris. Their EPS concentrations in glucose and lactose media were higher than other published strains of Lc. lactis subsp. cremoris. Low-fat fermented milk separately prepared with APL15 and APL16 reached pH 4.3 and acidity 0.8% with a viable count of 9 log colony-forming units/mL. The physical properties of both products were superior to the control yogurt, showing significant improvements in syneresis and viscosity (p<0.05). Our low-fat products had appropriate sensory scores in appearance and texture according to sensory evaluation. Although decreasing viable cells of strains during the 21-day storage test, low-fat fermented milk made by APL15 exhibited stable physicochemical properties, including pH value, acidity, syneresis and sufficient viable cells throughout the storage period.Conclusion: This study demonstrated that Lc. lactis subsp. cremoris APL15 isolated from TRFM had good fermentation abilities to produce low-fat fermented milk. These data indicate that EPS-producing lactic acid bacteria have great potential to act as natural food stabilizers for low-fat fermented milk.

REVISITING CONSUMER CONTAMINATION: INFLUENCES OF PROXIMITY AND SCOPE OF CONTACT

Fu-Yung Kuan,En-Chi Chang,Sin-Yao Chen 글로벌지식마케팅경영학회 2014 Global Marketing Conference Vol.2014 No.8

According to theory of consumer contamination (Argo, Dahl & Morales, 2006), a product, after being touched by a customer, will be disgusted and devalued by the following customer. However, Argo, et al. (2006) considered only a high salience of contact product, i.e., T-shirts, and did not consider low salience of contact products. This study extended the study of Argo, et al. (2006) and examined whether perception of consumer contamination varies between products of different saliences of contact. The gender difference was also considered. The result from an experiment showed that consumers’ reactions to ‘contaminated’ products vary, depending on the salience of contact. The result also shows that female consumers tend to be more sensitive to consumer contamination.

REVISITING CONSUMER CONTAMINATION: INFLUENCES OF PROXIMITY AND SCOPE OF CONTACT

Fu-Yung Kuan,En-Chi Chang,Sin-Yao Chen 글로벌지식마케팅경영학회 2014 Global Marketing Conference Vol.2014 No.7

According to theory of consumer contamination (Argo, Dahl & Morales, 2006), a product, after being touched by a customer, will be disgusted and devalued by the following customer. However, Argo, et al. (2006) considered only a high salience of contact product, i.e., T-shirts, and did not consider low salience of contact products. This study extended the study of Argo, et al. (2006) and examined whether perception of consumer contamination varies between products of different saliences of contact. The gender difference was also considered. The result from an experiment showed that consumers’ reactions to ‘contaminated’ products vary, depending on the salience of contact. The result also shows that female consumers tend to be more sensitive to consumer contamination.

Comprehensive profiles and diagnostic value of menopausal-specific gut microbiota in premenopausal breast cancer

Hou Ming-Feng,Ou-Yang Fu,Li Chung-Liang,Chen Fang-Ming,Chuang Chieh-Han,Kan Jung-Yu,Wu Cheng-Che,Shih Shen-Liang,Shiau Jun-Ping,Kao Li-Chun,Kao Chieh-Ni,Lee Yi-Chen,Moi Sin-Hua,Yeh Yao-Tsung,Cheng Chi 생화학분자생물학회 2021 Experimental and molecular medicine Vol.53 No.-

In Western countries, breast cancer tends to occur in older postmenopausal women. However, in Asian countries, the proportion of younger premenopausal breast cancer patients is increasing. Increasing evidence suggests that the gut microbiota plays a critical role in breast cancer. However, studies on the gut microbiota in the context of breast cancer have mainly focused on postmenopausal breast cancer. Little is known about the gut microbiota in the context of premenopausal breast cancer. This study aimed to comprehensively explore the gut microbial profiles, diagnostic value, and functional pathways in premenopausal breast cancer patients. Here, we analyzed 267 breast cancer patients with different menopausal statuses and age-matched female controls. The α-diversity was significantly reduced in premenopausal breast cancer patients, and the β-diversity differed significantly between breast cancer patients and controls. By performing multiple analyses and classification, 14 microbial markers were identified in the different menopausal statuses of breast cancer. Bacteroides fragilis was specifically found in young women of premenopausal statuses and Klebsiella pneumoniae in older women of postmenopausal statuses. In addition, menopausal-specific microbial markers could exhibit excellent discriminatory ability in distinguishing breast cancer patients from controls. Finally, the functional pathways differed between breast cancer patients and controls. Our findings provide the first evidence that the gut microbiota in premenopausal breast cancer patients differs from that in postmenopausal breast cancer patients and shed light on menopausal-specific microbial markers for diagnosis and investigation, ultimately providing a noninvasive approach for breast cancer detection and a novel strategy for preventing premenopausal breast cancer.