Relationship between antioxidant capacity and angiotensin-converting enzyme inhibitory activity of papain-generated protein hydrolysates and peptides from palm kernel cake proteins

Palm kernel cake (PKC) proteins were hydrolysed in the presence of seven proteolytic enzymes. The antioxidant and antihypertensive activities of each protein hydrolysate were evaluated. Papain-generated protein hydrolysate showed the highest antioxidant effects measured by radical scavenging activity (65%), iron (Fe)(II)-chelating activity (65%), and antihypertensive activity (71%). The results revealed a strong correlation between the antioxidant activity of the protein hydrolysates with angiotensin-converting enzyme (ACE) inhibitory activity (R2 = 0.69 - 0.98), except for trypsin-generated hydrolysate (R2= 0.22). The most potent protein hydrolysate was fractionated and profiled using reversed-phase high-performance liquid chromatography and isoelectric focusing; peptides were subsequently isolated and identified by tandem mass spectrometry. The individual peptides were evaluated for antihypertension potential. A positive correlation was identified between radical scavenging activity and Fe(II)-chelating activity together and ACE inhibitory activity with R2 = 0.69 - 0.98. The findings indicate that there was a positive relationship between the antioxidant and antihypertensive activities of protein hydrolysates and bioactive peptides from PKC proteins

Valorisation of virgin coconut oil application in mayonnaise production as functional Ingredient

Mayonnaise is favourable by large number of consumers due to the pleasant taste that can enhance the appetite. However, several commercial mayonnaises are produced by using high concentrations of oil that may cause high threats of developing several diseases due to the link to health issues. On the other hand, oils known for health promoting properties such as virgin coconut oil are underutilized even though having high potential as plant-based alternative healthy oil that can be used in mayonnaise production. In this study, virgin coconut oil was used to partially and/or fully replace soybean oil that is commonly used in mayonnaise production. Three mayonnaise samples were prepared by using three oil combinations including 100% virgin coconut oil, 50%:50% soybean oil:virgin coconut oil and 100% soybean oil. The antioxidant activity, physiochemical properties, lipid profile and sensory evaluation of the mayonnaise samples were determined by using standard methods. The results showed significantly higher antioxidant activity for the mayonnaise sample prepared with 100% virgin coconut oil in comparison to other two samples. No significant differences were observed for the physical properties including pH and colour. However, 100% virgin coconut oil mayonnaise sample had the largest droplet size, lowest texture firmness and lowest viscosity among the samples. The sensory evaluation demonstrated higher preference to the 100% soybean oil mayonnaise that scored total of 7.050, while the 100% virgin coconut oil mayonnaise scored 5.57 for overall acceptability. The findings of this study demonstrated high potential for using virgin coconut oil in mayonnaise production to improve the quality and the biological functions of the product while maintaining the organoleptic properties

Identification of antifungal peptides produced by Lactobacillus plantarum IS10 grown in the MRS broth

The use of secondary metabolites of lactic acid bacteria for preservation of foods is increasingly gaining interest to the food industry to replace synthetic preservatives. In this study, the cell free supernatant containing peptides obtained from Lactobacillus plantarum IS10 was fractionated by size exclusion chromatography using sephadex G-25, and tested against Aspergillus flavus MD3, Penicillium roqueforti MD4 and Eurotium rubrum MD5. Among the fractions, fraction number 10 showed 60% antifungal activity at a concentration of 0.02 mg peptide/mL. Four novel peptides out of twenty peptides obtained from fraction 10 were identified and determined by de novo sequencing. Peptide FPSHTGMSVPPP with a net charge +1, hydrophobicity ratio 58% and molecular weight of 1253 was further studied. The selected peptide showed a good activity at a concentration of 5 mg/mL against selected fungi and poor activity at low concentrations. This work indicates that L. plantarum IS10 has the capability of producing peptides which are affective against spoilage fungi

Lacto-fermented Kenaf (Hibiscus cannabinus L.) seed protein as a source of bioactive peptides and their applications as natural preservatives

Kenaf seeds are a promising source of natural preservatives for food applications due to their potential as a substrate to generate peptides with high antibacterial activity. We sought to generate bioactive peptides with antibacterial activity from Kenaf seed proteins via lacto-fermentation. The ground seeds were defatted and protein extracted using acid precipitation. Kenaf seed protein was fermented with Lactobacillus casei for 72 h at 37 °C, and the antibacterial activity, MIC, and MBC were determined using a 96-well microtiter plate assay. The fermented protein was subjected to fractionation and peptide identification using reversed-phase high pressure liquid chromatography and liquid chromatography-mass spectrometry, respectively. The fermented protein showed high antibacterial activity against Salmonella typhimurim, Escherichia coli, Psedomonas aerginosa, Staphylococcus aureus, Bacilus subtilis, and Streptococcus pyogenes. The MIC value was 4 mg/mL against all tested pathogens and the MBC value was 8 mg/mL against S. typhimurium, P. aureginosa, and E. coli and 4 mg/mL against B. subtilis, S. aureus, and S. pyogenes. Fraction 17 demonstrated the strongest antibacterial activity (98%–100%), and five peptides sequences were identified in this fraction. The findings of this study demonstrated high potential for kenaf seed protein fermented using Lactobacillus casei as a source of natural preservatives for a broad range of food applications

Production of banana cake premix from banana (Musa acuminata Colla) by-products via foam mat drying process

Introduction: Banana is a perishable fruit and rapidly overripe which can cause food waste problems to occur if not used to prepare other foods. Drying would be useful to overcome this problem by converting the overripe banana into a value-added product. Therefore, this study aims to evaluate the effect of different temperatures for foam mat drying on overripe banana puree. Besides, the sensory attributes and acceptability of banana cakes produced will be evaluated. Methods: The overripe banana puree was subjected to foam mat drying and the dried powder was subjected to banana cake production. Physical analysis, chemical analysis, and sensory evaluation were carried out for the banana cakes. Results: A significant different (p≥0.05) was observed for all of the overripe banana powder. The sensory evaluation showed that banana cake prepared from overripe banana powder and added with banana essence in the cake batter had significant difference (p<0.05) for the attributes of aroma, appearances, flavour, and after taste. In contrast, all the banana cakes samples showed no significant difference (p≥0.05) for the attribute of texture. Conclusion: This study showed that overripe banana powder has the potential to produce banana cake premix

Influence of storage conditions on the quality, metabolites, and biological activity of soursop (Annona muricata. L.) Kombucha

Kombucha is a slightly alcoholic beverage produced using sugared tea via fermentation using the symbiotic culture of bacteria and yeast (SCOBY). This study aimed to optimize the production of soursop kombucha and determine the effects of different storage conditions on the quality, metabolites, and biological activity. The response surface method (RSM) results demonstrated that the optimum production parameters were 300 ml soursop juice, 700 ml black tea, and 150 g sugar and 14 days fermentation at 28°C. The storage conditions showed significant (P < 0.05) effects on the antioxidant activity including the highest antioxidant activity for the sample stored for 14 days at 25°C in light and the highest total phenolic content (TPC) for the sample stored for 7 days at 4°C in the dark. No significant effects were observed on the antimicrobial activity of soursop kombucha toward Escherichia coli and Staphylococcus aureus. The microbial population was reduced from the average of 106 CFU/ml before the storage to 104 CFU/ml after the storage at 4 and 25°C in dark and light conditions. The metabolites profiling demonstrated significant decline for the sucrose, acetic acid, gluconic acid, and ethanol, while glucose was significantly increased. The storage conditions for 21 days at 25°C in the dark reduced 98% of ethanol content. The novel findings of this study revealed that prolonged storage conditions have high potential to improve the quality, metabolites content, biological activity, and the Halal status of soursop kombucha

Identification of antioxidant and antibacterial activities for the bioactive peptides generated from bitter beans (Parkia speciosa) via boiling and fermentation processes

The present study reports on the effects of boiling and fermentation processes on the antioxidant activity and antibacterial activity of the peptides generated from bitter beans. The protein content, peptide content, antioxidant activity and antibacterial activity were determined. The peptides were fractionated using size exclusion and the identified using LC-MS/MS in combination with PEAKS Studio software. The protein content for raw, boiled and fermented samples was 20, 15 and 13 g/100g DW and the peptide content was 0.3, 12.1 and 15.1 mg/g DW, respectively. Fermentation process increased the DPPH activity of bitter beans to 78.48 ± 3.16%. Fermentation process significantly increased the antibacterial activity of bitter beans towards Escherichia coli (45%), Salmonella Typhimurium (73%), Staphylococcus aureus (64%), and Listeria monocytogenes (57%). Out of the seven peptides identified in fraction 11, three peptides including EAKPSFYLK, PVNNNAWAYATNFVPGK and AIGIFVKPDTAV demonstrated antibacterial activity at different concentrations (1000, 500, 250 and 125 μg/mL). The DPPH activity was only observed for the peptides EAKPSFYLK (74%) and PVNNNAWAYATNFVPGK (87%). In conclusion, fermentation process increased the antioxidant and antibacterial activity of bitter beans due to the presence of low molecular weight peptides. The bioactive peptides are very promising ingredients to formulate functional foods and beverages

Production of functional non-dairy creamer using Nigella sativa oil via fluidized bed coating technology

Nigella sativa oil has a high potential to be developed into bioactive food ingredients. The aim of this study is to produce a lowfat, non-dairy creamer (NDC) from Nigella sativa oil (NSO) that is extracted by a supercritical fluid technique. The emulsion was processed with total solids of 40% and the drying process was performed using a spray dry technique at 160 °C inlet air temperature to obtain the microencapsulated oil. The agglomeration conditions (fluidizing time, fluid air temperature, and feed flow rate), were optimized using a response surface methodology (RSM) with a central composite design. The microencapsulated oil demonstrated low moisture content, high water solubility, strong antioxidant activity and high thymoquinone content in the developed creamer. The optimum conditions of the fluidized bed drying process were inlet air temperature (50 °C), drying time (25 min), and feed flow rate (1 mL/min). The sensory evaluation revealed that consumers’ acceptability is high for the developed coffee creamer. The findings indicated the high potential of the microencapsulated oil for applications to mass produce and commercialize functional non-dairy creamer

Applications of date (Phoenix dactylifera L.) fruits as bioactive ingredients in functional foods

The demand for food bioactive ingredients from natural sources with low cost and broad range of applications is extremely increasing. In this study, five date varieties marketed in Malaysia were evaluated for their potential applications as functional food ingredients. The date fruits were extracted with 80% ethanol, and biological activities including antioxidant, antibacterial and anti-elastase activity were determined by referenced methods. Results of the study showed that the date variety Piyarom demonstrated the highest antioxidant activity (IC50 11.3 µg/ mL), strong antibacterial activity towards tested pathogens that was ranged in 62-76 %, and strong anti-elastase activities (61.2±4.9%). The varieties Ajwa and Anbar showed moderate antioxidant and antibacterial activity, while Deglet Nour and Rabbi exhibited low activities. The results revealed high potential of Piyarom extract to be used as ingredient for functional food applications and fulfilled the high demand for natural functional food ingredients