Food Engineering and Bioprocess Technology

In this study, the effects of types of enzymes and degree of hydrolysis on functionalities, DPPH radical scavenging activity, and molecular weight distribution of the peanut protein hydrolysate (PPH) were investigated. Peanut protein was extracted from the oil cake by isoelectric precipitation method. The protein was subjected to controlled hydrolysis using alcalase and pepsin enzymes to yield products with different degrees of hydrolysis (8-17%). The main functional properties of hydrolysates such as solubility, fat absorption capacity (FAC), emulsifying activity index (EAI), emulsifying stability index (ESI) and DPPH radical scavenging activity were determined. Molecular weight distributions were analyzed using SDS-PAGE gel analysis. The results demonstrated that, under studied conditions, the functionalities of PPH were more dependent on types of enzymes than their degrees of hydrolysis. At the same DH, FAC (3.65-3.88 g oil/g PPH) and ESI (71.6-85.2%) of pepsin hydrolysates were higher than FAC (0.58-1.49 g oil/g PPH) and ESI (34.4-50.5%) of alcalase. However, alcalase PPH had better EAI and radical scavenging activity than that of pepsin. Hydrolyzed peanut protein had molecular weights predominantly < 15 kDa. The enzymes used had different specificities toward peanut protein hydrolysis indicated by the distinct molecular weight distribution and functionalities of the corresponding PPH. The findings, to a certain extent, could serve as an important basis for controlling and optimizing peanut protein hydrolysis for specific applications in food industries.

Microencapsulation involves coating or entrapping of a core material with a polymeric material to generate microspheres in the size range of 1-1000 lm. This versatile technology has been used to encapsulate a wide array of products such as pharmaceuticals, flavors, volatile oils, plant extracts, enzymes and others. In the recent decades, this technology has also been applied to the area of microbial cell immobilization owing to its numerous advantages over other cell immobilization techniques such as higher cell loading capacity, enhanced cell survival and increased production rate of the desired microbial products. The confinement of microbial cells within a semipermeable polymeric matrix enables the physical isolation of cells from the external environment while maintaining a hospitable internal micro-environment. It has found application in various biotechnological processes such as probiotic encapsulation in food industries, in biotransformation and fermentation processes producing antibiotics, organic acids, enzymes, and alcohols as well as environmental decontamination such as waste water treatment. The judicious selection of materials and methods for the production of microspheres is critical for ensuring minimum damage to the viability of the encapsulated microbial cells. The conventional methods used for microencapsulation of microbial cells are reviewed along with the recent advances in the respective methods. The effect of microencapsulation on the microbial cells, the stability of the microspheres as well as the techniques for enumeration of the encapsulated cells are also discussed, followed by a summary of recent applications of microencapsulation in different biotechnological processes.

Ultrasound-assisted extraction (UAE) was used to extract the anthocyanins from pericarp and lipids from the seeds of mangosteen. The optimum time for extraction of anthocyanin by maceration method and shaking water bath was 6 and 4 h, respectively, whereas, it was 5 min only for ultrasonic assisted extraction method. The anthocyanin content, extracted by UAE, was 23.54 mg Cyn-3-Glu/100 g. The regression equation derived by response surface methodology (RSM), was used to predict the anthocyanin content extracted by using UAE. The gas chromatography-flame ionized detector analysis showed that mangosteen seed contained both saturated (palmitic acid, 4.66 g/100 g; stearic acid, 47.64 g/ 100 g) and unsaturated fatty acids (oleic acid, 28.62 g/100 g; linoleic acid, 14.68 g/100 g). The mangosteen ice-cream exhibited up to 83.6 and 75.1 % DPPH inhibition, on addition of 2 and 1 % mangosteen pericarp extract respectively, where as control only 52.6 %.

Medicinal plants are frequently used for the treatment of various infectious diseases. The objective of this study was to evaluate the antibacterial activity and mode of action of Acacia nilotica and the antibiogram patterns of foodborne and clinical strains of Escherichia coli and Salmonella. The mechanism of action of acacia extracts against E. coli and Salmonella was elucidated by observing morphological damages including cell integrity and cell membrane permeability, as well as changes in cell structures and growth patterns in kill-time experiments. The clinical isolates of E. coli and Salmonella were found resistant to more of the tested antibiotics, compared to food isolates. Minimum inhibitory concentration and minimum bactericidal concentration of acacia leaf extracts were in the ranges of 1.56-3.12 mg/mL and 3.12-6.25 mg/mL, respectively, whereas pods and bark extracts showed somewhat higher values of 3.12-6.25 mg/mL and 6.25-12.5 mg/mL, respectively, against all tested pathogens. The release of electrolytes and essential cellular constituents (proteins and nucleic acids) indicated that acacia extracts damaged the cellular membrane of the pathogens. These changes corresponded to simultaneous reduction in the growth of viable bacteria. This study indicates that A. nilotica can be a potential source of new antimicrobials, effective against antibiotic-resistant strains of pathogens.

Background: The emergence of drug resistant malaria is threatening our ability to treat and control malaria in the Southeast Asian region. There is an urgent need to develop novel and chemically diverse antimalarial drugs. This study aimed at evaluating the antimalarial and antioxidant potentials of Acacia nilotica plant extracts. Methods: The antioxidant activities of leaves, pods and bark extracts were determined by standard antioxidant assays; reducing power capacity, % lipid peroxidation inhibition and ferric reducing antioxidant power assay. The antimalarial activities of plant extracts against Plasmodium falciparum parasites were determined by the 48 h schizont maturation inhibition assay. Further confirmation of schizonticide activity of extracts was made by extending the incubation period up to 96 h after removing the plant extract residues from parasites culture. Inhibition assays were analyzed by dose-response modelling. Results: In all antioxidant assays, leaves of A. nilotica showed higher antioxidant activity than pods and bark. Antimalarial IC 50 values of leaves, pods and bark extracts were 1.29, 4.16 and 4.28 μg/ml respectively, in the 48 h maturation assay. The IC 50 values determined for leaves, pods and bark extracts were 3.72, 5.41 and 5.32 μg/ml respectively, after 96 h of incubation. All extracts inhibited the development of mature schizont, indicating schizonticide activity against P. falciparum. Conclusion: A. nilotica extracts showed promising antimalarial and antioxidant effects. However, further investigation is needed to isolate and identify the active components responsible for the antimalarial and antioxidant effects.

The prevalence of two groups of antibiotics; namely penicillin and sulfonamides was studied in fresh milk available in Kathmandu Valley of Nepal. The milk samples (n = 140) were collected from three different sources; individual farmers, cottage dairies and organized dairies of Kathmandu valley. Qualitative and semi-quantitative analysis with rapid screening kits revealed that 23% samples were positive for antibiotic residues in the fresh milk for penicillin and sulfonamide groups (1-256 µg/kg). High performance liquid chromatography (HPLC) analyses detected 81% samples positive for amoxicillin (68-802 µg/kg), 41% for sulfadimethoxine (31-69 µg/kg), 27% for penicillin G (13-353 µg/kg), and 12% for ampicillin (0.5-92 µg/kg). Due to the precision and accuracy of liquid chromatography method, it detected more positive samples and consequently presented higher prevalence than the rapid screening kits. The antibiotic residues were found above the maximum residue limits that presented ser...

Ultrasonic assisted alkaline extraction of protein from banana flower was optimized using response surface methodology. The extracted proteins were characterized by Fourier transform infrared spectroscopy and molecular weight distribution was determined by gel electrophoresis. The maximum protein yield of 252.25 mg/g was obtained under optimized extraction conditions: temperature 50 °C, 30 min extraction time and 1 M NaOH concentration. The alkaline extraction produced a significantly high protein yield compared to enzymatic extraction of banana flower. Chemical finger printing of proteins showed the presence of tyrosine, tryptophan and amide bonds in extracted protein. Alkaline and pepsin assisted extracted banana flower proteins showed characteristic bands at 40 and 10 kDA, respectively. The extracted proteins showed antibacterial effects against both gram positive and gram negative bacteria. The high protein content and antimicrobial activity indicate the potential applications o...

Biodegradable packaging in food materials is a green technology based novel approach to replace the synthetic and conventional packaging systems. This study is aimed to formulate the biodegradable cassava starch based films incorporated with cinnamon essential oil and sodium bentonite clay nanoparticles. The films were characterized for their application as a packaging material for meatballs. The cassava starch films incorporated with sodium bentonite and cinnamon oil showed significant antibacterial potential against all test bacteria; , and Antibacterial effect of films increased significantly when the concentration of cinnamon oil was increased. The cassava starch film incorporated with 0.75% (w/w) sodium bentonite, 2% (w/w) glycerol and 2.5% (w/w) cinnamon oil was selected based on physical, mechanical and antibacterial potential to evaluate shelf life of meatballs. The meatballs stored at ambient temperature in cassava starch film incorporated with cinnamon oil and nanoclay, si...

Cassava is a high potential feedstock for bioethanol production in Asian countries, primarily due to high yield of carbohydrate per unit land, and its ability to grow on marginal lands with minimal agrochemical requirements. The objective of this study was to compare the bioethanol production from cassava starch with corn starch using a conventional and a raw/granular starch hydrolyzing process (GSH). The fermentation performance of cassava starch was compared with three corn starch types with different amylose: Amylopectin ratios. The final ethanol concentration with cassava starch was similar to that of two corn starch types, dent corn and waxy corn for both processes. For the cassava starch, the ethanol concentration achieved with GSH process was 2.8% higher than that in the conventional process. Cassava starch yielded the highest fermentation rates of the four starches investigated, during the conventional process. Ethanol production and fermentation profiles comparable with cor...

The freshwater green microalga Scenedesmus obliquus was cultivated to enhance the contents of proteins, carbohydrates and lipids by using Box-Behnken experimental design. S. obliquus was cultured under phototrophic conditions by using Bold's Basal Medium with different cultivation parameters including pH (7, 8 and 9), salinity (10, 30 and 50 mM), and nitrogen source (0.125, 0.5 and 1 g/L). The highest biomass yield (64.9 ± 0.94 mg/L/day) was obtained by using optimized medium at a salinity concentration of 30 mM (w/v), and nitrogen sources of 0.125 g/L. The maximum content of protein, lipid and carbohydrates from S. obliquus optimized medium were 342.19 ± 0.28 mg/g, 241.41 ± 4.32 mg/g and 288.05 ± 1.12 mg/g of dry wt. respectively. The amino acid and fatty acid analysis of S. obliquus biomass indicated the presence of significant amount of essential amino acids and essential fatty acids. Furthermore, chocolate crispy bar was developed by fortification with encapsulated freeze-dried S. obliquus and evaluated for its oxidative stability and sensory analysis. The chocolate fortified with microalgae can be a potential source of essential fatty acids and amino acids in addition to other bioactive compounds.

In this study, food grade nanoemulsions (NEs) were prepared with polyphenols (curcumin, gallic acid and quercetin); NEs were incorporated into the film forming solution at various concentrations (5%, 10% and 20% v/w of gelatin plus carrageenan). Moisture content and water solubility of film samples decreased with increasing NE concentration. Curcumin NE-loaded gelatin composite films exhibited highest antioxidant activity (27.20 ± 0.02, 45.9 ± 0 and 60.51 ± 0.36%) at 5%, 10% and 20% NE concentrations, respectively. Curcumin NE-loaded composite gelatin films also exhibited antimicrobial activity against both Salmonella typhimurium (6.97 ± 0.03 mm) and Escherichia coli (7.47 ± 0.09 mm). The chemical finger printing of films was evaluated by Fourier-transform infrared spectroscopy. Curcumin NE-loaded films showed excellent results by increasing the shelf-life of fresh broiler meat up to 17 days in comparison to control (10 days), hence can be used as alternative to conventional packaging.

The influence of dietary vitamin D 3 (VD3) levels on growth, bone performance, and duodenal type IIb sodium-dependent phosphate cotransporter (NaPi-IIb) genes in broiler chicken were studied. One-dayold male Ross308 broilers (n 5 432) were allocated into 6 treatment groups with each group consisting of 6 cage pens. Each treatment group received diet containing different amounts of VD3 (80, 200, 500, 1,250, 3,125, or 7,813 IU per kg of diet) from a day-old to 31 D of age. Dietary available phosphorus and calcium were kept the same across all treatments in each phase. At 14 D, influence of VD3 on BW gain was found in the birds that received VD3 of 3,125 IU/kg and 200 IU/kg (P , 0.05). Toe ash and tibia ash linearly increased (P , 0.05) at 14 D with increase in dietary VD3. There was no significant influence of dietary VD3 on tibia breaking strength. In both phases, relative expression of duodenal NaPi-IIb linearly increased (P , 0.01) with increase in dietary VD3. At 14 D, highest expression of 3.2 folds was observed in birds treated with VD3 at 7,813 IU/kg of feed. At 31 D, birds that received VD3 levels of 3,125 and 7,813 IU/kg of feed showed 2.9 folds higher in NaPi-IIb expression compared with those fed lowest level of VD3 at 80 IU/kg of feed. When dietary calcium and phosphorus were maintained at the standard requirement, increase in dietary VD3 did not improve growth performance. For optimum growth and bone characteristics, dietary inclusion of VD3 at 500 IU/kg was adequate for both starter and grower broiler diets. Vitamin D 3 enhanced the expression of NaPi-IIb at higher doses and thus improving the tibia ash content in high VD3 treatment groups. This study reported for the first time an increased in the expression of duodenal NaPi-IIb in 31-day-old broilers in response to high dietary VD3 levels.

For the first time, pregnant women will have a happy and curious feeling about the changes in themselves and fetal development in general. However, there is also a feeling of anxiety. The research conducted in Naples, Italy, March, 15 th-April, 1 st , 2020, showed that the Covid-19 pandemic has a severe psychological impact on 53% of pregnant women. The study stated that pregnant women could be feeling stressed and anxious, which could cause adverse effects such as fetal death or fetal abnormalities. Antenatal Care is a pregnancy check that aims to improve the physical and mental health of pregnant women optimally. Therefore, they can ensure with childbirth, preparation for exclusive breastfeeding, and return to reproductive health properly. This study aimed to provide counseling about psychological changes in pregnant women and how to get pregnancy services during the Covid-19 pandemic. Pregnant women need to conduct pregnancy checkup regularly to health practitioner or midwifery and health cadres andcarry out prenatal checks according to the minimum standard. This extension activity was implemented for pregnant women and health cadres in Kertosari Village in stages with keeping applicable health protocol. The results showed the enthusiasm of pregnant women and health cadres who accompanied them during the pregnancy checkup process.

This study focused on the optimization of xylitol production from sugarcane bagasse by using response surface methodology (RSM). Xylitol was produced through a series of processes, firstly, optimization of ultrasound assisted mild alkaline pretreatment for the xylan extraction from sugarcane bagasse followed by enzymatic hydrolysis of xylan to xylose by enzyme β-1,4-xylanase and finally microbial fermentation of xylose to xylitol using yeast (Candida guilliermondii), bacteria (Corynebacterium glutamicum) and their mixed culture for different time periods (0-96 h). Maximum xylan recovery of 12.059% (w/w) was observed at pretreatment; 0.73 M NaOH, 1:38.55 solid to liquid ratio and 34.77 min ultrasonication. The enzyme concentration of 400 U/g xylan at 48 h of incubation showed the highest xylose production (81.51 mg/g bagasse). Yeast (Candida guilliermondii) resulted in the highest xylitol yield (Yp/s= 0.43 g/g) after 72 h. This bioprocess route can contribute as a suitable alternative for chemical methods of xylitol production.

Helicobacter pylori is a pathogenic bacterium causing gastric problems such as, peptic ulcers and stomach cancer. H. pylori were isolated from the stomach biopsy specimens (n = 100) of gastric patients by performing polymerase chain reaction (PCR) against cagA (cytotoxin associated gene A) and ureC (Urease subunit alpha) genes. Furthermore, antibiogram studies of the H. pylori isolates were evaluated against the common antibiotics. The overall detection rate of H. pylori was 71% in biopsy specimens of gastric patients. The antimicrobial susceptibility test revealed the resistance rate of H. pylori isolates against metronidazole (50%), clarithromycin (28.33%), tetracycline (21.66%), amoxicillin (18.33%), and ciprofloxacin (11.66%). However, the H. pylori isolates were completely resistant to vancomycin, erythromycin and nalidixic acid antibiotics. Clove oil showed a remarkable antimicrobial effect against H. pylori whereas, mild inhibition (10 mm) was observed in case of curcumin extract. Due to increase incident of resistance and high prevalence of H. pylori in gastric patients, natural antimicrobial like clove oil can be explored as an alternative treatment.

The aim of this research was to determine the probiotic potential and safety of lactic acid bacteria (LAB) isolated from raw goat milk. Gram positive and catalase negative bacteria were isolated from raw goat milk (n = 61) and identified as LAB. LAB isolates were screened for antimicrobial, probiotic and technological characteristics. LAB isolates showed antimicrobial activity against foodborne pathogens (Staphylococcus aureus, Escherichia coli and Salmonella Typhimurium) and high survival rate at pH 2 (93.54-100.38% after 4h), in the presence of 0.3% bile salts (100.85-108.96% after 4h) and simulated gastric fluid (74.16-80.13% after 3h). Three LAB isolates (1, 3 and 13) with high antimicrobial activity against all foodborne pathogens and probiotics characteristics were subjected to 16S rRNA sequencing and identified as Enterococcus faecium strains. Enterococcus spp. exhibited milk coagulation potential, amylolytic activity, susceptibility to antibiotics and no evidence of hemolysis. Enterococcus spp. isolated from goat milk showed probiotic and technological characteristics and can be used as a starter culture after further safety evaluation.

The aim of this research was to determine the probiotic potential and safety of lactic acid bacteria (LAB) isolated from raw goat milk. Gram positive and catalase negative bacteria were isolated from raw goat milk (n = 61) and identified as LAB. LAB isolates were screened for antimicrobial, probiotic and technological characteristics. LAB isolates showed antimicrobial activity against foodborne pathogens (Staphylococcus aureus, Escherichia coli and Salmonella Typhimurium) and high survival rate at pH 2 (93.54-100.38% after 4h), in the presence of 0.3% bile salts (100.85-108.96% after 4h) and simulated gastric fluid (74.16-80.13% after 3h). Three LAB isolates (1, 3 and 13) with high antimicrobial activity against all foodborne pathogens and probiotics characteristics were subjected to 16S rRNA sequencing and identified as Enterococcus faecium strains. Enterococcus spp. exhibited milk coagulation potential, amylolytic activity, susceptibility to antibiotics and no evidence of hemolysis. Enterococcus spp. isolated from goat milk showed probiotic and technological characteristics and can be used as a starter culture after further safety evaluation.