Bioactive Ingredients in Functional Foods: Current Status and Future Trends

Bioactive ingredients (BI) bestow various health-promoting outcomes on consumers, including treating or preventing diabetes, obesity, cancer, coronary heart diseases, and so on. Several BI have been found in nature, such as flavonoids, carotenoids, polyphenols, curcumin, phytosterols, probiotics, bioactive peptide, minerals, and nano-bio minerals, which can be incorporated into foodstuffs to improve their nutritional values. The foods containing BI are considered functional food. This review shed light on the health benefits of various BI for consumers. Due to the growing rate of population and surging demands for healthy foods in the future, it is pivotal to use affordable natural sources of BI to provide functional foods for a vast majority of people. Thus, in this review article, some potent by-products are addressed as alternative sources of BI

Technological Assessment of Autochthonous Lactic Acid Bacteria and their Antibacterial Activities Against Food borne Pathogens in Goat Milk Lactic Cheese: LAB as biopreservative in dairy products

Background and Objective: Lactic cheese is a highly consumed dairy product that is of great nutritional values. However, great concerns are reported regarding their safety, microbial quality and short shelf life. Addition of antimicrobial compound-producing lactic acid bacteria as protective cultures is known to improve safety and ensure quality of food products. The current study was carried out to assess antibacterial and several technological characteristics of autochthonous Lactic acid bacterial isolates for their use in goat milk lactic cheese to control Staphylococcus aureus and Listeria monocytogenes. Material and Methods: Antibacterial and other technological characteristics, including proteolytic activity, diacetyl production, autolytic activity and survival, in various NaCl concentrations and at suboptimal temperatures of several Lactic acid bacteriasolates were assessed. The potent isolates were identified to species level by phenotypic and genotypic methods (16 srRNA gene sequencing) and finally they were assessed for their ability to inhibit Staphylococcus aureus and Listeria monocytogenes in prepared goat milk lactic cheese. Results and Conclusion: Lactic acid bacterial isolates, showing significant antibacterial action, proteolytic activity and diacetyl production, were identified as Lactiplantibacillus plantarum RTCC 1290-1, Lactobacillus acidophilus RTCC 1299 and Lacticaseibacillus casei RTCC 1296-1. These isolates survived at 25 and 45 ºC, tolerated up to 8% NaCl and 55 ºC for 10 min (p≤0.01). Lactobacillus acidophilus demonstrated the highest autolytic activity (38.69%) followed by Lacticaseibacillus casei (28.44%) and Lactiplantibacillus plantarum (18.38%), respectively. Cocultures of the selected lactic acid bacterial isolates in goat milk lactic cheese resulted in a 5 log CFU g-1 decrease in Listeria monocytogenes, while, Staphylococcus aureus counts decreased by only 3 Log CFU g-1 (p≤0.05) during a month of storage at room temperatures. However, lactic acid bacterial counts increased 2–4 Log CFU g-1 from Day 15, which was reported stable up to Day 30. In conclusions, Lacticaseibacillus casei, Lactiplantibacillus plantarum and Lactobacillus acidophilus bears promising biopreservative effect for the control of foodborne pathogens. Conflict of interest: The authors declare no conflict of interest

Heavy Metal Bioremediation Potential of Autochthonous Lactic Acid Bacteria for Use in Edible Leafy Vegetables

Heavy metals are well-known as destructive environmental pollutants that cause serious health problems. The use of bacterial biological biosorption has been proposed as a practical and environmentally friendly solution for the removal of heavy metals. The current study was conducted in in vitro and in situ conditions. Initially, seven strains of lactic acid bacteria with probiotic properties (Lacticaseibacillus casei, Lacticaseibacillus rhamnosus, Lactiplantibacillus plantarum, Limosilactobacillus fermentum, Enterococcus faecium, Lactobacillus helveticus, and Lactobacillus acidophilus) were screened for their ability to bind cadmium, lead, and nickel in an aqueous solution. Three of the potent probiotic strains that showed the highest biosorption efficiency at this stage were selected for further analysis. The effect of these bacteria mixed at a ratio of 1 : 1 : 1 on the removal of toxic metals in fresh leaves of edible vegetables including coriander, leek, and parsley was evaluated within 15 and 30 minutes. During in vitro analysis, the sorption percentage of Pb and Cd appeared higher than 99% during 15 minutes of initial contact, while increasing contact time (30 minutes) had no significant effect on the removal of these metals. While during in situ analysis, Ni sorption by the selected lactic acid bacteria (LAB) isolates was significantly enhanced with increasing contact time, such that the highest biosorption rate was recorded in coriander leaves at 30 minutes (91.15%). Overall, E. faecium showed the highest sorption of Pb, Cd, and Ni (79.75 ± 0.11, 75.28 ± 0.05, and 83.99 ± 0.10%), respectively. The combination of three bacterial strains had a synergistic effect on the toxic metal binding capacity compared to the single state of these bacteria, and the biosorption level increased to 99.94 ± 0.02, 99.91 ± 0.01, and 93.75 ± 0.04%, respectively. Scanning electron microscopic (SEM) observations and energy dispersive X-ray (EDX) analysis confirmed that the majority of Pb, Cd, and Ni were bound to the surface of the bacterial cell

a-amylase from white pitaya Hylocereus undatus L. peel: optimization of extraction using full factorial design

Introduction. Amylase is a significant enzyme with numerous commercial applications, which is largely used to convert starches into oligosaccharides. Extraction of amylase from plant by-products or cheap sources is cost-effective. Annually, pitaya fruit juice industry produces huge amounts of peels that could be utilized as an alternative source in enzyme production industry. The work aimed to examine and optimize extraction process. Study objects and methods. In this study, we investigated parameters of extraction to optimize the process, as well as activity of α-amylase from white pitaya fruit (Hylocereus undatus L.) peel. For this purpose, a two-level full factorial design was applied. Three variables, namely the pH of sodium phosphate buffer (X1, 4.5–7.5), mixing time (X2, 1–3 min), and a sample-to-buffer ratio (X3, 1:3–1:5), were used to identify significant effects and interactions within the samples. Results and discussion. The results demonstrated that the buffer pH had the most significant (P ≤ 0.05) effect on total amylase activity. Based on full factorial design analysis, we revealed the optimal conditions for amylase enzyme extraction ‒ pH of 6, mixing time of 2 min, and a sample-to-buffer ratio of 1:4. Lower and higher values influenced adversely on specific activity of amylase. Conclusion. Optimization increased the enzyme specific activity by a factor of 4.5. Thus, pitaya peel could be used in different industries as a rich natural α-amylase source

The Effect of the COVID-19 Pandemic on the Factors Influencing Iranian Medical Residents' Specialty Selection: A Qualitative Study

Background: Medical students' specialty selection influences the composition of the physician workforce and the effectiveness of health systems. Therefore, the identification of factors that influence the choice of specialty is critical for an evidence-based health policy. This study aimed to investigate the effect of the Coronavirus Disease 2019 (COVID-19) pandemic on the determinants of specialty choice among Iranian medical residents. Methods: In early 2022, this qualitative study was conducted among Iranian medical residents in seven provinces, including Tehran, Isfahan, Fars, Khorasan Razavi, Kerman, Kermanshah, and Khuzestan. The participants were selected using a purposeful sampling method. Data were collected using 74 semi-structured in-depth face-to-face interviews. Finally, a thematic content analysis (conventional content analysis) method was applied for data synthesis. Results: The participant's mean age was 28.7±2.5 years, and more than 52% (N=39) were men. Following data synthesis, 10 sub-themes and four main themes were identified, including educational aspects affected by the pandemic, career-related hazards, personal and professional lifestyles affected by the disease, and experiences and beliefs regarding the pandemic. Conclusion: The COVID-19 pandemic has had a significant impact on medical students' educational, professional, and personal aspects of specialty choices. This study demonstrated how the disease affected the choice of specialty. Therefore, the findings could be used for developing national health policy and planning