Tempoyak is a functional Malaysian food (an acid-fermented condiment) which is produced from the pulp of the durian (Durio zibethinus) fruit. The current study aimed to isolate and identify potential exopolysaccharide (EPS)-producing Lactobacillus strains from tempoyak for potential use as probiotics. Seven isolates (DUR2, DUR4, DUR5, DUR8, DUR12, DUR18, and DUR20) out of 44 were able to produce EPS, and exhibited resistance to acid and bile salt compared to the reference strains Lactobacillus rhmnosus (ATCC53103) and L. plantarum (ATCC8014). The seven isolated strains belonged to five different species—L. plantarum, L. fermentum, L. crispatus, L. reuteri, and L. pentosus—which were identified using API 50 CHL and 16S rRNA gene sequences (Polymerase chain reaction, PCR – based). The seven strains displayed different ability to produce EPS (100–850 mg/L). Isolates exhibited a high survivability to acid (pH 3.0), bile salts (0.3%), and gastrointestinal tract model (<70%). Results showed that the auto-aggregation and cell surface hydrophobicity ranged from 39.98% to 60.09% and 50.80% to 80.53%, respectively, whereas, the highest co-aggregation value (66.44%) was observed by L. fermentum (DUR8) with Pseudomonas aeruginosa. The isolates showed good inhibitory activity against tested pathogens, high antioxidant activity (32.29% to 73.36%), and good ability to reduce cholesterol (22.55% to 75.15%). Thus, the seven tested strains have value as probiotics.
1 January 2016 in Evidence-Based Complementary and Alternative Medicine
The Nigella sativa L. popularly referred to as black seeds are widely used as a form of traditional nutrition and medicine. N. sativa seeds were used for the extraction of their oil by way of supercritical fluid extraction (SFE) and cold press (CP) to determine the physicochemical properties, antioxidant activity, and thermal behavior. The GC‐MS results showed the primary constituents in the Nigella sativa oil (NSO) were Caryophyllene (17.47%) followed by thymoquinone (TQ) (11.80%), 1,4‐Cyclohexadiene (7.17%), longifolene (3.5%), and carvacrol (1.82%). The concentration of TQ was found to be 6.63 mg/mL for oil extracted using SFE and 1.56 mg/mL for oil extracted by CP method. The antioxidant activity measured by DPPH and the IC50 was 1.58 mg/mL and 2.30 mg/mL for SFE oil and cold pressed oil, respectively. The ferric reducing/antioxidant power (FRAP) activity for SFE oil and CP oil was 538.67 mmol/100 mL and 329.00 mmol/100 mL, respectively. The total phenolic content (TPC) of SFE oil was 160.51 mg/100 mL and 94.40 mg/100 mL for CP oil presented as gallic acid equivalents (GAE). This research showed that a high level of natural antioxidants could be derived from NSO extracted by SFE.
This study aims to evaluate the probiotic properties of Lactobacillus strains producing exopolysaccharides (EPS) isolated from different Malaysian fermented foods. Thirty lactobacilli species were isolated, and six of these (TAP1, PIC7, BU11, BU14, TAP16, and TEMP9) were shown to exhibit probiotic characteristics with the potential to produce EPS. The isolates were evaluated for their tolerance to low pH, bile salts, antimicrobial potential, and cell surface properties. The strains were identified using API50CHL and 16S rRNA gene sequences as Lactobacillus belonged to the species fermentum and plantarum. The Lactobacillus strains exhibited high survivability tolerance to low pH and bile salts (above 90%). All strains exhibited auto-aggregation (33.63–59.63%), co-aggregation (24.37–41.9%), and hydrophobicity (16–65.77%) ability. The strains displayed no transferrable antibiotics and antagonistic activity against pathogenic bacteria. Therefore, it indicates that Lactobacillus strains could act as promising probiotic candidates.
31 December 2017 in International Journal of Food Properties
Microencapsulation is frequently used to enhance the stability of liquid food by transforming it to a free-flowing powder. This study aimed to evaluate the effect of storage for 24 days at 65°C on the overall quality and stability of microencapsulated Nigella sativa oil (MNSO) compared to uncapsulated Nigella sativa oil (NSO). During storage time, the total oil was extracted from the MNSO and was examined every six days along with the uncapsulated NSO. The uncapsulated oil showed many changes to its properties including reductions in oxidative stability, content of bioactive compounds, and antioxidant activity, as well as changes in fatty acid composition. The same parameters were evaluated for MNSO, which showed increased stability and resistance under the same storage conditions. The results confirmed the efficacy of the microencapsulation in protecting the oil.
Cheddar cheese proteolysis were accelerated employingPenicillium candidumPCA1/TT031 protease into cheese curd. In the present study, several of the significant factors such as protease purification factor (PF), protease concentration and ripening time were optimized via the response surface methodology (RSM). The ideal accelerated Cheddar cheese environment consisted of 3.12 PF, 0.01% (v/v) protease concentration and 0.6/3 months ripening time at 10 °C. The RSM models was verified to be the most proper methodology for the maintain of chosen Cheddar cheese. Under this experimental environment, the pH, acid degree value (ADV), moisture, water activity (aw), soluble nitrogen (SN)%, fat and overall acceptability were found to be 5.4, 6.6, 35%, 0.9348, 18.8%, 34% and 13.6, respectively of ideal Cheddar cheese. Furthermore, the predicted and experimental results were in significant agreement, which confirmed the validity and reliability of the suggested method. In spite of the difference between the ideal and commercial Cheddar cheese in the concentration of some of amino acids and free fatty acids, the sensory evaluation did not show any significant difference in aroma profile between them.