The detection of lactate is an important indicator of the freshness, stability, and storage stability of products as well as the degree of fermentation in the food industry. In addition, it can be ...used as a diagnostic tool in patients’ healthcare since it is known that the lactate level in blood increases in some pathological conditions. Thus, the determination of lactate level plays an important role in not only the food industry but also in health fields. As a result, biosensor technologies, which are quick, cheap, and easy to use, have become important for lactate detection. In the current study, amperometric lactate biosensors based on lactate oxidase immobilization (with Nafion 5% wt) were designed and the limit of detection, linear range, and sensitivity values were determined to be 31 μM, 50–350 μM, and 0.04 μA μM−1 cm−2, respectively. Then, it was used for the measurement of lactic acid that produced by six different and morphologically identified presumptive lactic acid bacteria (LAB) which are isolated from different naturally fermented cheese samples. The biosensors were then used to successfully perform lactate measurements within 3 min for each sample, even though a few of them were out of the limit of detection. Thus, electrochemical biosensors should be used as an alternative and quick solutions for the measurement of lactate metabolites rather than the traditional methods which require long working hours. This is the first study to use a biosensor to measure lactate produced by foodborne LAB in a real sample.
The selection of proper probiotic culture is essential for maintaining adequate numbers of viable cells until consumption since potential adverse interaction between selected strain and starter ...culture. This study examined the suitability of Cacık as a potential probiotic carrier
including Lactobacillus acidophilus 74-2, Lactobacillus rhamnosus Howaru HN001TM and Bifidobacterium longum BB536 in different combinations. The presence of three probiotic strains caused higher post
acidification and shorter fermentation time associated to higher counts
of L. bulgaricus. Except for certain combinations containing B. longum BB536, the counts of individual probiotic bacteria were higher than 6 log g-1 for all probiotic supplemented Cacık samples. Results showed that bacterial interaction was decisive for survival over 21 days of storage. Probiotic products containing only B. longum BB536 or B. longum
BB536 with L. acidophilus 74-2 did not accomplish in terms of the technological point, since the viable cell counts decerased for 2.45 log
and 1.95 log per g, respecitevly, throughout the storage period. In three of totally four combinations included L. rhamnosus Howaru HN001TM alone or combined with other probiotic bacteria, the viable cell counts of L. rhamnosus Howaru HN001TM remained at the inoculated level, while the counts significantly increased in co-culture with L. acidophilus 74-2. Considering the overall sensorial attributes and survival of probiotics, Cacık supplemented with L. rhamnosus Howaru HN001TM alone, combinations of B. longum BB536 and L. rhamnosus Howaru HN001TM or L. acidophilus 74-2 and L. rhamnosus Howaru HN001TM or by all of the three tested probiotics, were suggested as suitable for further production.
Izbor odgovarajuće probiotičke kulture neophodan je za održavanje adekvatnog broja živih stanica do potrošnje, budući da postoji potencijalno nepovoljna interakcija između odabranog soja i starter kulture. Ova studija ispitala je prikladnost Cacıka kao potencijalnog nositelja probiotika, uključujući Lactobacillus acidophilus 74-2, Lactobacillus rhamnosus Howaru HN001TM i Bifidobacterium longum BB536 u različitim kombinacijama. Prisutnost tri probiotika uzrokovala je višu postacidifikaciju i kraće vrijeme fermentacije povezano s većim brojem stanica soja L. bulgaricus. Osim određenih kombinacija koje sadrže B. longum BB536, broj pojedinačnih probiotičkih bakterija bio je veći od 6 log g-1 za sve uzorke Cacık s dodatkom probiotika. Rezultati su pokazali da je bakterijska interakcija bila presudna za preživljavanje tijekom 21 dana skladištenja. U uzorcima koji su sadržavali soj B. longum BB536 sam ili u kombinaciji sa sojem L. acidophilus 74-2 zabilježen je pad broja živih stanica za 2,45 log i 1,95 log po g, zbog čega su se ove kombinacije pokazale neuspješnima u smislu kreiranja probiotičkog proizvoda. U tri od ukupno četiri uzorka koji su sadržavali soj L. rhamnosus Howaru HN001TM sam ili u kombinaciji s drugim probiotičkim sojevima, broj živih stanica L. rhamnosus Howaru HN001TM održao se na početnoj inokuliranoj razini, dok se značajno povećao u ko-kulturi s L. acidophilus 74-2. Uzimajući u obzir ukupna senzorska svojstva i preživljavanje probiotika, Cacık s dodatkom pojedinačnih sojeva L. rhamnosus Howaru HN001TM ili B. longum BB536 i L. rhamnosus Howaru HN001TM ili L. acidophilus 74-2 i L. rhamnosus Howaru HN001TM ili sva tri probiotika može se smatrati pogodnim za daljnju proizvodnju.
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•The most abundant hydroxycinnamic acid in quince peel and leaf are chlorogenic acid.•The leaf had the highest phenolic content, antioxidant and antimicrobial activity.•The biological ...activity decreased after digestion in quince parts except the seed.•K. pneumoniae ATCC 700603 were not inhibited by any quince parts of extracts.
In this study, the phenolic extracts of Eşme quince parts (pulp, peel, seed, juice, and leaf) were obtained under optimized extraction conditions. Then, the total phenolic content (TPC), the quantities of main phenolic compounds, antioxidant, and antimicrobial activity and the change in bioactivity properties (TPC, antioxidant capacity, and antimicrobial activity on the same sixteen microorganisms) after in vitro digestion of each quince part were evaluated. The order of TPC and antioxidant activity was determined as leaf > peel > juice > pulp > seed. After in vitro gastrointestinal digestion, a decrease was observed for the TPC (average 5-fold reduction) and antioxidant activity (more than 2.5-fold reduction) in all quince parts except quince seed than their extract forms. The quince leaf extract exhibited the highest antibacterial activity. Overall, this study exhibited that the quince leaf was considered a promising, cheap, and natural source for nutritional or pharmaceutical applications with biological activity properties.
The aim of study to investigate inhibition effects of cinnamic acid (volatile compound of cinnamon), limonene (essential oil of lemon) and eugenol (essential oil of clove, cinnamon) on Metschnikowia ...fructicola, Candida oleophila, Schisosaccharomyces pombe, Saccharomyces uvarum and Kloeckera apiculata. In this study, tube dilution method was used. Among eugenol, limonene and cinnamic acid, it was found that cinnamic acid has the most inhibition effect with low concentrations (%2.8, %3.84, %4.36, %5,4) at tube dilution methods. Also it was found that test yeast have different resistance against test materials.
Lemon grass (Cymbopogon citratus L.) oil has been known as having therapeutic and antibacterial properties, and its antifungal activity is currently the subject of renewed interest. This study aimed ...to verify the effectivenesses of C. citratus essential oil to inhibit the growth/survival of some fungi (Alternaria alternata, Aspergillus niger, Fusarium oxysporum, and Penicillium roquefortii) and yeasts (Candida albicans, Candida oleophila, Hansenula anomala, Saccharomyces cerevisiae, Schizosaccharomyces pombe, Saccharomyces uvarum, and Metschnikowia fructicola). C. citratus essential oil showed effectiveness in inhibiting the growth of all fungi by disc diffusion and broth dilution bioassay. Minimum inhibitory and minimum fungicidal concentrations between 0.062 and 20 microL/mL were determined. The Clinical and Laboratory Standards Institute agar-based method was also applied for A. niger and C. albicans. Data show the strong antifungal properties of lemon grass oil (C. citratus) in vitro.
Abstract The growing interest of consumers to the new probiotic product has led the industry to focus on it. But viability of probiotic strain has a big challenge during shelf life of food. ...Therefore, to know the effect of food additives on survival of probiotic is important. The role of probiotics, garlic and yoghurt on the health of humans is widely known. In this study, we focus on finding answers to the question of whether selected beneficial bacteria will survive in the presence of ground garlic solution or fresh garlic juice and obtaining the growth parameters of that strains. Disk diffusion assays revealed that while Bifidobacterium longum BB536 is the most susceptible (49.37 ± 1.07 mm), Lactobacillus acidophilus 74-2 is the most resistant (no inhibition zone) bacteria to the fresh garlic juice, significantly. However, the strains were not adversely affected in possible usage rates of garlic in some Turkish appetizers. Enumeration assays also confirmed these unexpected findings. The addition of certain quantities of ground garlic or fresh garlic juice that did not show antimicrobial activity for selected probiotic strains are suitable for food matrix, especially yogurt based products.
The proximate composition of eleven walnut (Juglans regia L.) genotypes (28 ŞK 010, 28 ŞK 055, 28 ŞK 041, 28 ŞK 601, 28 ŞK 925, 28 ŞK 028, 28 ŞK 118, 28 ŞK 350, 28 ŞK 930, 28 ŞK 850, 28 ŞK 036) and ...three walnut cultivars (Şebin, Bilecik, Kaman 1) produced in Turkey were determined. The oil content of the samples ranged from 61.32 to 69.35%, corresponding to an energy value of approximately 710 kcal per 100 g of kernel. The protein content ranged from 10.58 to 18.19%, and the carbohydrate composition was between 9.05 and 18.92%. The ash content ranged from 1.53 to 1.99%, and the moisture content of the kernels was between 1.91 and 4.48% the oleic acid content of the oils ranged from 17.90 to 33.35% of the total fatty acids. The linoleic acid content ranged from 43.15 to 60.20%. The linolenic acid content ranged from 9.98 to 13.00%. The palmitic acid content was between 5.21 and 8.40%. Stearic acid ranged from 2.36 to 4.25%. Potassium was the major mineral in all the samples, ranging from 359.73 to 482.97 mg/100 g. Calcium was the next most abundant mineral, ranging from 109.45 to 335.97 mg/100 g, followed by magnesium, ranging from 126.01 to 165.15 mg/100 g.