This study aimed at utilizing ultrasound treatment to further enhance the growth of lactobacilli and their isoflavone bioconversion activities in biotin-supplemented soymilk. Strains of lactobacilli (Lactobacillus acidophilus BT 1088, L. fermentum BT 8219, L. acidophilus FTDC 8633, L. gasseri FTDC 8131) were treated with ultrasound (30 kHz, 100 W) at different amplitudes (20%, 60% and 100%) for 60, 120 and 180 s prior to inoculation and fermentation in biotin-soymilk. The treatment affected the fatty acids chain of the cellular membrane lipid bilayer, as shown by an increased lipid peroxidation (P<0.05). This led to increased membrane fluidity and subsequently, membrane permeability (P<0.05). The permeabilized cellular membranes had facilitated nutrient internalization and subsequent growth enhancement (P<0.05). Higher amplitudes and longer durations of the treatment promoted growth of lactobacilli in soymilk, with viable counts exceeding 9 log CFU/mL. The intracellular and extracellular β-glucosidase specific activities of lactobacilli were also enhanced (P<0.05) upon ultrasound treatment, leading to increased bioconversion of isoflavones in soymilk, particularly genistin and malonyl genistin to genistein. Results from this study show that ultrasound treatment on lactobacilli cells promotes (P<0.05) the β-glucosidase activity of cells for the benefit of enhanced (P<0.05) isoflavone glucosides bioconversion to bioactive aglycones in soymilk.
The aim of the present work was to produce a new soy milk-based cake. Soy milk was added at different percentages (0, 25, 50, 75, and 100%) during cake making to replace milk. Nutritional composition, batter characteristics, physical, and sensory properties, as well as the stability of cake during storage, were investigated. Sensory results indicated that cake with 50% soy milk had the most favourable acceptance scores with the highest score in the aroma, colour, and taste attributes. The addition of soy milk up to 50% produced a cake with higher protein content and lower carbohydrate content, along with lower density and higher specific volume compared to control. Cake with 50% soy milk addition had lower microbial counts as compared to control. Therefore, soy milk has the potential to act as a milk replacer in cake production.
This study aimed to evaluate the effects of ultrasound on Lactobacillus fermentum BT 8633 in parent and subsequent passages based on their growth and isoflavone bioconversion activities in biotin-supplemented soymilk. The treated cells were also assessed for impact of ultrasound on probiotic properties. The growth of ultrasonicated parent cells increased (P<0.05) by 3.23-9.14% compared to that of the control during fermentation in biotin-soymilk. This was also associated with enhanced intracellular and extracellular (8.4-17.0% and 16.7-49.2%, respectively; P<0.05) β-glucosidase specific activity, leading to increased bioconversion of isoflavones glucosides to aglycones during fermentation in biotin-soymilk compared to that of the control (P<0.05). Such traits may be credited to the reversible permeabilized membrane of ultrasonicated parent cells that have facilitated the transport of molecules across the membrane. The growing characteristics of first, second and third passage of treated cells in biotin-soymilk were similar (P>0.05) to that of the control, where their growth, enzyme and isoflavone bioconversion activities (P>0.05) were comparable. This may be attributed to the temporary permeabilization in the membrane of treated cells. Ultrasound affected probiotic properties of parent L. fermentum, by reducing tolerance ability towards acid (pH 2) and bile; lowering inhibitory activities against selected pathogens and reducing adhesion ability compared to that of the control (P<0.05). The first, second and third passage of treated cells did not exhibit such traits, with the exception of their bile tolerance ability which was inherited to the first passage (P<0.05). Our results suggested that ultrasound could be used to increase bioactivity of biotin-soymilk via fermentation by probiotic L. fermentum FTDC 8633 for the development of functional food.
The objective of this study was to evaluate agricultural wastes as immobilizers for probiotics in liquid foods, such as soy milk. Probiotic strains were initially evaluated for acid and bile tolerance and the ability to produce alpha-galactosidase. Rinds of durian, mangosteen, and jackfruit were dried, ground, and sterilized prior to immobilization of selected strains ( Lactobacillus acidophilus FTDC 1331, L. acidophilus FTDC 2631, L. acidophilus FTDC 2333, L. acidophilus FTDC 1733, and Lactobacillus bulgaricus FTCC 0411). Immobilized cells were inoculated into soy milk, and growth properties were evaluated over 168 h at 37 degrees C. Soy milk containing free cells without agrowastes was used as the control. Immobilized probiotics showed increased growth, greater reduction of stachyose, sucrose, and glucose, higher production of lactic and acetic acids, and lower pH in soy milk compared to the control. The results illustrated that agrowastes could be used for the immobilization of probiotics with enhanced growth, utilization of substrates, and production of organic acids.
Time and temperature parameters of superheated steam (SHS) treatment were optimised using response surface methodology (RSM) for specific lipoxygenase (LOX) activity in soya beans and crude protein content in soya milk. The optimal SHS treatment was obtained at 9.3 min and 119 °C. The predicted values of specific LOX activity and crude protein content by RSM were 0.0098 μmol/(min mg protein) and 3.2%, respectively. These values were experimentally verified to be 0.0081 ± 0.0002 μmol/(min mg protein) and 3.0 ± 0.1%, respectively. Sensory evaluation showed that the beany flavour of soya milk produced from SHS treated soya beans was significantly weaker (P milk significantly (P milk complied with Malaysian Food Regulations 1985.
This study was aimed at an evaluation of the potential inheritance of electroporation effects on Lactobacillus fermentum BT 8219 through to three subsequent subcultures, based on their growth, isoflavone bioconversion activities, and probiotic properties, in biotin-supplemented soymilk. Electroporation was seen to cause cell death immediately after treatment, followed by higher growth than the control during fermentation in biotin-soymilk (P<0.05). This was associated with enhanced intracellular and extracellular beta-glucosidase specific activity, leading to increased bioconversion of isoflavone glucosides to aglycones (P<0.05). The growing characteristics, enzyme, and isoflavone bioconversion activities of the first, second, and third subcultures of treated cells in biotin-soymilk were similar to the control (P>0.05). Electroporation affected the probiotic properties of parent L. fermentum BT 8219, by reducing its tolerance towards acid (pH 2) and bile, lowering its inhibitory activities against selected pathogens, and reducing its ability for adhesion, when compared with the control (P<0.05). The first, second, and third subcultures of the treated cells showed comparable traits with that of the control (P>0.05), with the exception of their bile tolerance ability, which was inherited to the treated cells of the first and second subcultures (P<0.05). Our results suggest that electroporation could be used to increase the bioactivity of biotin-soymilk via fermentation with probiotic L. fermentum BT 8219, with a view towards the development of functional foods.
The objective of the present study was to evaluate the effects of ultrasound on the growth of probiotics and bioconversion of isoflavones in prebiotic-soymilk. Previous studies have shown that ultrasound elevated microbial enzymatic activity and growth by altering cellular membranes. The growth of probiotics was significantly decreased (P < 0.05) immediately after ultrasound treatment, attributed to membrane permeabilization, cell lysis, and membrane lipid peroxidation upon ultrasound treatment. The ultrasound treatment also caused alteration at the acyl chain, polar head, and interface region of the probiotic membrane phospholipid bilayers. The cells treated with ultrasound showed recovery from injury with subsequent increase in growth upon fermentation in soymilk (P < 0.05). Ultrasound treatment at 100 W for 2 and 3 min also enhanced (P < 0.05) the intracellular and extracellular β-glucosidase activity of probiotics, leading to increased (P < 0.05) bioconversion of glucosides to aglycones in the prebiotic-soymilk. Our present study illustrated that ultrasound treatment could produce bioactive synbiotic-soymilk with increased concentrations of bioactive aglycones.
This study analyzed the effect of pH (X1), temperature (X2) and inulin amount (X3) on transformation of isoflavones (daidzin and daidzein) to equol in soymilk fermented with Bifidobacterium spp. All responses significantly (p 0.05) difference between the experimental and predicted values, suggested the suitability of established models in explaining the daidzin and daidzein transformation to equol as a function of pH, temperature and inulin.
Ten strains of Lactobacillus were evaluated for their viability in soymilk. Lactobacillus acidophilus ATCC 314, L. acidophilus FTDC 8833, L. acidophilus FTDC 8633 and L. gasseri FTDC 8131 displayed higher viability in soymilk and were thus selected to be evaluated for viability and growth characteristics in soymilk supplemented with B-vitamins. Pour plate analyses showed that the supplementation of all B-vitamins studied promoted the growth of lactobacilli to a viable count exceeding 7 log CFU/ml. alpha-Galactosidase specific activity of lactobacilli as determined spectrophotometrically showed an increase upon supplementation of B-vitamins. High-performance liquid chromatography analyses revealed that this led to increased hydrolysis of soy oligosaccharides and subsequently higher utilization of simple sugars. Production of organic acids as determined via high-performance liquid chromatography also showed an increase, accompanied by a decrease in pH of soymilk. Additionally, the supplementation of B-vitamins also promoted the synthesis of riboflavin and folic acid by lactobacilli in soymilk. Our results indicated that B-vitamin-supplemented soymilk is a good proliferation medium for strains of lactobacilli.
Probiotics has been discovered long time ago for its beneficial effect on health when consumed especially to the people who had allergy and gastrointestinal disease. This preliminary study was conducted to find out which vehicles can allow better growth of probiotic. Lactobacillus plantarum was used in this study as choice of probiotic to be cultured in the four types of milk. The pH value was recorded for determination of growths and metabolic activity of the probiotic. Results showed that L. plantarum in soy milk can grow and had a better metabolic activity in the cultured soy milk with pH 3.46 compared to others. The highest growth was recorded at optical density of 1.137 in soy milk at 560nm. This result showed that L. plantarum in soy milk multiply rapidly compared to other milks. As conclusion, soy milk has better development of probiotic as delivery vehicles compare to cow milk, goat milk and coconut milk.
This study examined lactic acid bacteria (LAB)-fermented soymilk for their ability in hydrolyzing glucosides to aglycones
and corresponding antioxidant capacity and memory enhancing effect. Twelve LAB isolated from Malaysian fermented food
and milk products were incubated in commercially available soymilk for 48 h. Generally, soymilk supported LAB growth
and significantly increased (p<0.05) conversion to bioactive aglycone by 2.1-6.5 fold when compared to unfermented
soymilk. Lactobacillus fermentum LAB 9- fermented soymilk, in particular, was presented with increased total phenolic
content (+10%) as opposed to unfermented soymilk. Lactobacilli (LAB 10-12)- and pediococci (LAB 5)-fermented soymilk
elicited maximal DPPH radical-scavenging activity. LAB 1, 7, 8, 9 and 12 exhibited significantly higher (p<0.05) ferrous
ion chelating activity when compared to control. Interestingly, LAB 9 had significantly improved memory deficit (p<0.05)
in LPS-challenged mice. LAB-enriched nutritional value of soymilk could be useful against oxidative stress and memory
deficit.
The ability to detect the presence of transgenes in crop-derived foods depends on the quantity and quality of DNA obtained from a product to be analyzed. The efficiency of DNA extraction protocols differs due to the nature of each food product. In this paper, we described two main DNA extraction protocols and their modifications that have been applied and evaluated for DNA extraction from raw and processed food as well as animal feed. The yield and quality for five categories of food and feed samples namely, raw soybean, raw maize, animal feed, smooth tofu and soymilk are discussed. The statistical interaction analyses showed that the cetyltrimethyl ammonium bromide (CTAB) method was proven to be the best method to extract DNA from raw soybean, maize and animal feed samples which not only obtained high DNA yield of 32.7, 28.4 and 33.4 ng DNA/mg sample respectively, but also produced high quality DNA with the absorbance A260/A280 ratio of 1.9, 1.9 and 2.0, respectively. These DNA were suitable for PCR amplification which produced a 164 bp DNA fragment of the lectin gene from soybean, and a 277 bp DNA fragment of the zein gene from maize. In the processed food category, the Wizard isolation method was found to be the best for the extraction of DNA from smooth tofu and soymilk with the yield of 13.2 and 3.4 ng DNA/mg sample, and the quality of the DNA at the absorbance A260/A280 ratio ranged from 1.9 to 1.7. These DNA were successfully amplified using primers specific to the lectin gene of soybean.
This study aimed at utilizing electroporation to further enhance the growth of lactobacilli and their isoflavone bioconversion activities in biotin-supplemented soymilk. Strains of lactobacilli were treated with different pulsed electric field strength (2.5, 5.0 and 7.5 kV/cm) for 3, 3.5 and 4 ms prior to inoculation and fermentation in biotin-soymilk at 37°C for 24 h. Electroporation triggered structural changes within the cellular membrane of lactobacilli that caused lipid peroxidation (p 9 log CFU/ml after fermentation in biotin-soymilk (p
Soy products have attracted much attention lately as carriers for probiotics. This study was aimed at enhancing the growth of probiotics in soymilk via supplementation with prebiotics.
The objective of this study was to evaluate the effects of ultraviolet (UV) radiation (UVB; 90 J/m²) on growth, bioconversion of isoflavones and probiotic properties of parent and subsequent passages of L. casei FTDC 2113. UV radiation significantly enhanced (P < 0.05) the growth of parent cells in mannitol-soymilk fermented at 37°C for 24 h. This had led to an enhanced intracellular and extracellular β-glucosidase activity with a subsequent increase in bioconversion of isoflavones in mannitol-soymilk (P < 0.05). UV radiation also promoted (P < 0.05) the tolerance of parent cells towards acidic condition (pH 2 and 3) and intestinal bile salts (oxgall, taurocholic and cholic acid). In addition, parent treated cells also exhibited better (P < 0.05) adhesion ability to mucin and antimicrobial activity compared to that of the control. All these positive effects of UV radiation were only prevalent in the parent cells without inheritance by first, second and third passage of cells. Although temporary, our results suggested that UV radiation could enhance the bioactive and probiotic potentials of L. casei FTDC 2113, and thus could be applied for the production of probiotic products with enhanced bioactivity.
Probiotics are live microorganisms that confer health benefits through the gastrointestinal microbiota. This nutritional supplement may benefit athletes who undergo rigorous training by maintaining their gastrointestinal functions and overall health. In this study the influence of moderate physical exercise using a graded treadmill exercise, alone or in combination with the consumption of a soy product fermented with Lactobacillus plantarum LAB12 (LAB12), on tumour necrosis factor alpha (TNF-α) responses was investigated in a murine model. Male BALB/c mice were randomly divided into four groups of six mice each (control, exercise alone, LAB12 and LAB12 + exercise). Mice treated with the potential probiotic LAB12 were orally gavaged for 42 days. At autopsy, blood and spleen from the animals were collected. The splenocytes were cultured in the presence of a mitogen, concanavalin A (Con A). The amount of TNF-α produced by the Con A-stimulated splenocytes was quantified using ELISA, while their proliferation was determined using the [(3)H]-thymidine incorporation method. This study shows that LAB12-supplemented and exercise-induced mice showed marked increase (P<0.05) in cell proliferation compared to the control animals. TNF-α production was suppressed (P<0.05) in the LAB12 group compared to the untreated mice. These results demonstrate that supplementation with LAB12 has immunomodulatory effects, under conditions of moderate physical exercise, which may have implications for human athletes. Further investigation in human trials is warranted to confirm and extrapolate these findings.
The aim of this study was to evaluate the effects of ultraviolet (UV) radiation (ultraviolet A (UVA), ultraviolet B (UVB) and ultraviolet C (UVC) at 30-90 J/m²) on the membrane properties of lactobacilli and bifidobacteria, and their bioconversion of isoflavones in prebiotic-soymilk. UV treatment caused membrane permeabilization and alteration at the acyl chain, polar head and interface region of membrane bilayers via lipid peroxidation. Such alteration subsequently led to decreased (p < 0.05) viability of lactobacilli and bifidobacteria immediately after the treatment. However, the effect was transient where cells treated with UV, particularly UVA, grew better in prebiotic-soymilk than the control upon fermentation at 37°C for 24 h (p < 0.05). In addition, UV treatment also increased (p < 0.05) the intracellular and extracellular β-glucosidase activity of lactobacilli and bifidobacteria. This was accompanied by an increased (p < 0.05) bioconversion of glucosides to bioactive aglycones in prebiotic-soymilk. Our present study illustrated that treatment of lactobacilli and bifidobacteria with UV could develop a fermented prebiotic-soymilk with enhanced bioactivity.
Cell immobilization is an alternative to microencapsulation for the maintenance of cells in a liquid medium. The objective of this study was to evaluate the effects of agrowastes from durian (Durio zibethinus), cempedak (Artocarpus champeden), and mangosteen (Garcinia mangostana) as immobilizers for lactobacilli grown in soymilk. Rinds from the agrowastes were separated from the skin, dried, and ground (150 microm) to form powders and used as immobilizers. Scanning electron microscopy revealed that lactobacilli cells were attached and bound to the surface of the immobilizers. Immobilized cells of Lactobacillus acidophilus FTDC 1331, L. acidophilus FTDC 2631, L. acidophilus FTDC 2333, L. acidophilus FTDC 1733, and L. bulgaricus FTCC 0411 were inoculated into soymilk, stored at room temperature (25 degrees C) and growth properties were evaluated over 168 h. Soymilk inoculated with nonimmobilized cells was used as the control. Utilization of substrates, concentrations of lactic and acetic acids, and changes in pH were evaluated in soymilk over 186 h. Immobilized lactobacilli showed significantly better growth (P < 0.05) compared to the control, accompanied by higher production of lactic and acetic acids in soymilk. Soymilk containing immobilized cells showed greater reduction of soy sugars such as stachyose, raffinose, sucrose, fructose, and glucose compared to the control (P < 0.05).
Lactobacillus sp. FTDC 2113, L. acidophilus FTDC 8033, L. acidophilus ATCC 4356, L. casei ATCC 393, Bifidobacterium FTDC 8943 and B. longum FTDC 8643 were incorporated into soymilk supplemented with fructooligosaccharides (FOS), inulin, mannitol, maltodextrin and pectin. The objective of the present study was to evaluate the effects of prebiotics on the bioactivity of probiotic-fermented soymilk. Proteolytic activity was increased in the presence of FOS, while the supplementation of inulin and pectin increased the angiotensin I-converting enzyme inhibitory activity accompanied by lower IC(50) values. The beta-glucosidase activity was also enhanced in the presence of pectin. This led to higher bioconversion of glucosides to aglycones by probiotics, especially genistin and malonyl genistin to genistein. Results from this study indicated that the supplementation of prebiotics enhanced the in-vitro antihypertensive effect and production of bioactive aglycones in probiotic-fermented soymilk. Therefore, this soymilk could potentially be used as a dietary therapy to reduce the risks of hypertension and hormone-dependent diseases such as breast cancer, prostate cancer and osteoporosis.
Kefir is a fermented milk obtained by fermenting milk with kefir grains. The chemical composition ofdairy and non-dairy sources may affect the growth and characterisation of lactic acid bacteria (LAB). In this study, different sources of milk (cow milk) and non-dairy milk (soymilk and coconut milk) were used as the fermentation media for kefir products. The objectives of the study were to isolate and characterise LAB from kefir drink produced from dairy and non-dairy milk. LAB was isolated using different cultural methods, such as MRS Agar, MRS with 0.8% CaCO3, and M17 Agar. The characteristics of the LAB isolates were determined using morphological, biochemical tests and the API 50 CHL kit. The physicochemical composition of the samples was determined using titratable acidity and pH level. Sensory evaluation of the kefir drink samples was also carried out. Results confirmed that the isolates were identified as Lactobacillus buchneri, Lactobacillus brevis 1, Leuconostoc mesenteroides, Lactobacillus acidophilus 3and Lactobacillus plantarum 1. The L. buchneri, L. brevis, Leu. mesenteroides and L. acidophilus are heterofermentative bacteria, whereas L. plantarum is a homofermentative bacterium. Four LAB isolates have the potential to be used as probiotic strains due to their high resistant to low pH and bile salt. The sensory scores of these products range between 5.00 and 8.00 in the 9-point hedonic scale. Most of the sensory panelists preferred cow milk kefir (p < 0.05) compared with coconut milk kefir and soy milk kefir during the sensory evaluation of all attributes. Meanwhile, the preference between coconut milk kefir and soy milk kefir was similar (p>0.05) in all attributes. Therefore, this study will be useful for probiotic manufacturers in the production of alternative probiotic drinks using dairy and non-dairy milk.