Applied Food Biotechnology
Volume:9 Issue: 1, Winter 2022

Production of γ - aminobutyric acid has recently much interested because of its benefits for health. T he objective of this study was to optimize γ - aminobutyric acid production by a novel identified Lactiplantibacillus pentosus isolated from a fermented shrimp paste of ruoc.

A species of lactic acid bacterial was isolated from ‘ruoc’, a high - salt fermented shrimp paste and identified using matrix - assisted laser desorption/ionization - time of flight mass spectrometry. The γ - aminobutyric acid production was optimized using various culture conditions ( initial cell density from 5  10 5 to 5  10 7 CFU ml - 1 , monosodium glutamate concentration of 0.5 - 2% (w v - 1 ), initial pH of 4 - 9, incubation temperature of 30 - 50 °C and incubation time of 24 - 120 h) with one - factor - at - a - time approach.

Of 20 lactic acid bacteria isolated from ‘ruoc’, four isolates of R1, R3, R12 and R13 produced significant quantities of γ - aminobutyric acid. Isolate R13 produced the highest γ - aminobutyric acid quantity, identified as Lactiplantibacillus pentosus using matrix - assisted laser desorption/ionization - time of flight mass spectrometry. A culture media optimization study was carried out for Lactiplantibacillus p entosus R13 to improve its γ - of 1.5% monosodium aminobutyric acid yield. Results showed that at optimal conditions , cultivation 1 - CFU ml 6 10  ), initial pH of 7, initial cell density of 5 1 - glutamate (w v temperature of 45 °C and fermentation time of 96 h, Lactiplantibacillus pentosus R13 produced 23.34 mM ±0.11 of γ - aminobutyric acid. In conclusion , γ - aminobutyric acid production by this isolate was verified to be heavily dependent on monosodium glutamate concentration, initial cell density, initial pH, incubation temperature and fermentation ti

Resveratrol is a polyphenol with nutraceutical health benefits used as anticancer, antioxidant and anti - inflammatory with cardio protective effects. However, resveratrol lacks solubility and bioavailability and is affected by UV light, which decrease its use in food industries. It is possible to overc ome these problems by loading resveratrol with appropriate biomaterials. Beta - lactoglobulin is known to form well - defined nanofibrils with various uses. The objective of this study was to use β - lg nanoscaled fibrils to increase bioavailability of resveratr ol as well as preserving freshness and preventing enzymatic browning of sliced apples.

Novel composite nanofibrils were prepared by loading resveratrol on Beta - lactoglobulin nanofibrils using simple self - assembly method. Furthermore, atomic force microscopy, scanning electron microscopy, in - vitro release assay, weight loss, total acidity, total phenolic content and antioxidant activity studies were carried out to verify the biochemical s ustainable release and bioavailability. Results and

Atomic force microscopy and scanning electron microscopy images showed the formation of well - defined composite nanofibrils with an average aspect ratio of 1000; as shown in other studies. In - v itro release assay revealed that resveratrol was successfully loaded on nanofibrils due to possible hydrogen bonding interactions and other non - covalent linkages. The highest encapsulation efficiency of 61.1% was achieved using low concentrations of resver atrol (10mg in 1ml), whereas encapsulation efficiency of 48.3% was achieved for high concentrations of resveratrol (20mg in 1ml). The assessed weight loss, total acidity, color, total phenolic content and antioxidant activities showed ~50% increases in the shelf - life and prevention of enzymatic browning due to improved bioavailability of resveratrol. The current study could successfully demonstrate antioxidant potency of resveratrol in sliced apples and help better protections against ageing. The formula ca n be used as a protective layer on high - value food products such as fruits susceptible to deteriorative condition

Ursolic acid is a pentacyclic triterpenoid with various biological characteristics. The objective of this study was to investigate potentially biological activities of ursolic acid extracted from apple peels.

Ursolic acid was extracted from apple peels and purified using colu mn chromatography. Then, the biochemical was analyzed using ultraviolet - visible spectroscopy , high - performance thin - layer chromatography , Fourier - transform infrared spectroscopy and nuclear magnetic resonance techniques. Antimicrobial effects of the purifi ed ursolic acid on pathogenic bacterial species of Pseudomonas aeruginosa , Escherichia coli , Staphylococcus aureus and Bacillus subtilis were assessed using minimum inhibitory concentration and disc diffusion methods. Furthermore, the biochemical radical scavenging ability was assessed using 1,1 - diphenyl - 1 - picrylhydrazyl method. Wound healing characteristics of the purified ursolic acid was studied using scratch assay method.

Minimum inhibitory concentration and disc diffusion results verified antibacterial effects of ursolic acid on Gram - positive bacterial species. Ursolic acid at concentra - tions higher than 625 μg m l - 1 showed significant antioxidant activity, compared to that vitamin C did as reference antioxidant. It was shown that migration and proliferation of human umbilical vein endothelial cells can be promoted by the extracted ursolic acid, which was assessed via wound healing assays and 3 (4,5 ‐ dimethylthiazol ‐ 2 ‐ yl) ‐ 2,5 ‐ diphenyltetrazolium bromide. Wound closure was 97%, revealed by the purified ursolic acid after 24 h. A low concentration of ursolic acid (< 20 μg ml - 1 ) stimulated proliferation of human umbilica l vein endothelial cells; however, 100 μg ml - 1 of the extracted ursolic acid decreased the number of viable cells within 24 h ( p < 0.05) . Purified ursolic acid ( 10 μg ml - 1 ) was able to upregulate (almost two times) FLT1 and VEGF - A gene expression in human umbilical vein endothelial cells . Results suggest that ursolic acid is an effective antioxidant and includes excellent antibiotic characteristics. In addition, it can affect endothelial cell proliferation, which is significant to enhance angiogenesis and i mprove wound healing processe

Propionic acid bacteria are useful microorganisms that can produce beneficial food compounds . These bacteria mainly produce propionic acid that decrease the microbial population and growth along with increasing the shelf life. Propionibacterium freudenreichii was applied to produce propionic acid in yogurt in this study.

First, the process variables like inoculum percentage, strain type, milk fat and inulin amount, fermentation temperature, sunflower oil qu antity, and refrigerated duration on propionic acid production by Propionibacterium freudenreichii was evaluated using Plackett - Burman design as a screening method. Next the acid production was optimized by a central composite design with 3 major factors o f seed size, concentration of inulin, and refrigerated storage.

Analysis of variance showed that the models have been significant (p≤0.05). They represented that propionic acid production was influenced by three main factors. Optimized propionic acid production in yogurts by Propionibacterium freudenreichii ssp. shermanii (10 8 CFU. ml - 1 ) was observed in 21 d ays after of refrigeration of skim - milk 2% (w v - 1 ), inulin (3% w v - 1 ) and incubation temperature of 43 °C. Reconfirmation test showed that the highest produced propionic acid was 12.53 ± 0.24 mg l - 1 in yogurt, which increased production up to 6.2 time. Results showed that Propionibacterium freudenreichii ssp. shermanii increases propionic acid contents in synbiotic yogurts containing inulin.

Microbial contamination can cause undesirable changes in food products. In addition to consumer’s health, these changes can challenge the product market. Doogh as one of the traditional dairy may be contaminated by a wide range of microbiota. Awareness of the contaminant types can be an accurate strategy to eliminate contaminations. Regarding importance of food safety as well as industry demand, the present study was an attempt to better understanding of the yeast microbiota diversity in spoiled Doogh. Also the effect of predominant yeast metabolites on proteins and peptides profiling of Doogh were investigated. Results demonstrated purposeful industrial strategies to secure quality parameters and boos t the shelf life of Doogh.

Swollen packages of pasteurized Doogh samples were collected from a local dairy plant within one year. Identification was carried out using morphological, biochemical and molecular techniques. Then, protein and peptide profiles of the inoculated Doogh samples with high proteolytic activities of the isolated yeasts were compared with control using SDS - PAGE and MALDI - TOF - MS techniques.

Totally, 13 isolates belonged to two genera of Kluyveromyces and Candida were isolated and identified. Based on 18S rRNA gene sequencing, eight isolates were identified as Kluyveromyces marxianus ; four isolates were matched with Kluyveromyces lactis and one isolate was identified as Candida kefyr . Furt hermore, o - phthaldialdehyde assay showed that Kluyveromyces marxianus contain the highest proteolytic activity, compared to other identified isolates. Results showed that the activity of Kluyveromyces marxianus linked the protein profiles to β - lactogluboli n and α - lactalbumin isoforms and several peptides with molecular weight less than 10 kDa. Small changes in organoleptic properties can directly affect the product marketing and jeopardizes survival of the industries. By increasing necessary measures on the critical points in the production lines, adoption of right strategies to decrease or eliminate contaminants and hence improve the quality of the products is poss

Biodiesel is a well - known liquid fuel. However, a large quantity of glycerol is produced as a byproduct during the biodiesel production . If this is used as a substrate for value - added products such as monoacylglycerols, economic viability of the biodiesel process may improve . There are various uses of monoacylglycerol . However, its use as a substrate for oleogel is still a challenge. Therefore, the aim of this study was to assess the optimum acylglycero l production by immobilized lipase using glycerol from biodiesel processing and various plant oils as substrates . Moreover, use of acylglycerol for oleogel production was studied .

First, glycerol was collected from biodiesel plants and purified using repeated cycles of acidification. Purified glycerol and various types of plant oils, including coconut, rice bran and palm oils, were used to produce acylglycerol via immobilized lipase catalysis. Then, acylglycerols from each plant oil were selected and used as substrates for oleogels. Acylglycerol was characterized following standard methods using gas chromatography - mass spectroscopy and Fourier transformed infrared spectroscopy. Moreo ver, structure and develop of oleogel were assessed using Fourier transformed infrared spectroscopy and scanning electron microscopy.

The highest acylglycerol yield (91.15%) was achieved under conditions, including 20% enzyme loadin g, 6:1 glycerol to palm oil ratio, 8% water content, 40 °C reaction temperature and 24 - h reaction time. Acylglycerol from glycerol with palm oil included mono, di and triacylglycerols with contents of 85.0, 10.0 and 2.0%, respectively. Results showed that types of oil included no effects on oleogel qualifications in this study and all oleogels included good characteristics use in foo

Lentinus edodes (Shiitake) is a rich source of secondary metabolites, including exopolysaccharides. These compounds strengthen the immune system and play essential roles in prevention and treatment of several diseases, in cluding cancers. A way to increase production of polysaccharides is the use of elicitors. Examples of these elicitors include microbial volatile organic compounds, which are produced in microo - rganism co - cultures. The objective of this study was to investi gate effects of these compounds on production of Shiitake exopolysaccharides.

To decrease cultivation time, Shiitake was cultured in four culture media, including (1) potato dextrose broth, (2) potato dextrose broth and D - glucose, (3) malt extract broth and (4) malt extract broth and D - glucose. After selecting appropriate culture media, fungal growth curve, kinetic growth of pellets and filamentous morphology were studied. Novel method of simultaneous aerial co - culture wa s used to increase production of Shiitake exopolysaccharides, which acted as an elicitor by inducing microbial volatile organic compounds of other microorganisms. Microbial volatile organic compounds were analyzed using gas chromatography - mass spectroscopy . Results and

Malt extract medium containing glucose was selected for submerged and solid cultures of Shiitake and the growth time decreased to 18 d. Shiitake biomass production included 11 g.l - 1 . Filamentous morphology included higher product ion rates due to higher surface - to - volume ratios, compared to that the pellet morphology did. Shiitake fungal biomass and exopolysaccharides in co - cultures with Aspergillus niger included 14 and 4 g.l - 1 , respectively . Furthermore, biomass and exopolysaccha rides included 11 and 4.7 g.l - 1 in co - cultures with Schizophyllum commune , respectively . Microbial volatile organic compounds produced by Aspergillus niger and Schizophyllum commune in co - cultures, as elicitors, increased biomass and exopolysaccharide productions in Shiitake. Therefore, it suggests that microorganism co - cultivation is a low - cost effective method for Shiitake exopolysaccharide production