The germination of lamtoro gung has been shown to increase the angiotensin-I-converting enzyme inhibitory (ACE-I) activity in previous studies. The 48 h germinated flour had the highest ACE-I activity. Administration of the gastrointestinal digestion (GID) simulation with commercial enzymes was expected to increase the ACE-I activity. However, the GID simulation to increase ACE-I in the germinated lamtoro gung flour has not been found. Therefore, this study aimed to evaluate the GID simulation of ACE-I peptides in sprouted lamtoro gung flour. This study also identified and characterised the peptide with the ACE-I activity. The GID simulation was performed using commercial pepsin (pH 2) and pancreatin (pH 7.5). Both simulations occurred at 37 °C for 240 min. The degree of hydrolysis, peptide concentration, and ACE-I activity was analysed. Samples with the highest ACE-I activity were then fractionated and identified, to determine the peptide responsible for the ACE-I activity. The 180 min GID simulation in the test sample showed the highest ACE-I activity (89.70%). This result was supported by an increased degree of hydrolysis (DH) and peptide concentrations throughout the GID simulation. The <1 kDa peptide fraction had the highest inhibitory activity and had the most elevated peptide portion (54.69%). Peptide sequences containing crucial amino acids were found in the <1 kDa peptide fraction. PRPPKPP, PPPPPGARAP, and PFPPSNPPP had proline in the C and N terminal residues. The peptides obtained also had other biological activities, such as a DPP IV inhibitor, an alpha-glucosidase inhibitor, and antioxidative activity. Based on the toxicity prediction, those peptides are non-toxic and safe to consume.

Research background. High blood pressure is the most significant cause of mortality globally. Some fermented foods include ACE-inhibitory peptides that help fight this disease. The ability of fermented jack bean (tempeh) to inhibit ACE during consumption has not been demonstrated yet. This study identified and characterised ACE-inhibitory peptides from jack bean tempeh produced by small intestine absorption using the everted intestinal sac model. Experimental approach. Sequentially, the protein extract of jack bean tempeh and unfermented jack bean was hydrolysed using pepsin-pancreatin for 240 min. The hydrolysed samples were then evaluated for the peptide absorption using three-segmented everted intestinal sacs (duodenum, jejunum and ileum). The peptides absorbed from all intestinal segments were mixed in the small intestine. Results and conclusions. The data showed that both jack bean tempeh and unfermented jack bean had the same peptide absorption pattern, with the highest percentage of peptide absorption in the jejunum, followed by the duodenum and ileum. The absorbed peptides of jack bean tempeh exhibited equally strong activity of ACE inhibition in all intestinal segments, while the unfermented jack bean showed strong activity only in the jejunum. The mixture of the peptides from jack bean tempeh absorbed in the small intestine had higher ACE-inhibitory activity (81.09 %) than the unfermented jack bean (72.22 %). The peptides produced from jack bean tempeh were identified as pro-drug ACE inhibitors and had the mixed inhibition pattern. The mixture of peptides consisted of seven types of peptides with a molecular mass of 826.86–978.20 Da (DLGKAPIN, GKGRFVYG, PFMRWR, DKDHAEI, LAHLYEPS, KIKHPEVK, and LLRDTCK). Novelty and scientific contribution. This study discovered that consuming jack bean tempeh generated more potent ACE-inhibitory peptides during small intestine absorption than cooked jack beans. Absorbed tempeh peptides have high ACE-inhibitory activity.

The extraction of white jack bean (Canavalia ensiformis) protein isolate frequently leaves a lot of precipitates containing complex carbohydrates such as starch, dietary fiber, and resistant starch. Repeated autoclaving – cooling cycles can increase the content of soluble fiber and resistant starch. The aim of this study was to determine changes of dietary fiber and resistant starch content of complex carbohydrates of white jack bean during autoclaving-cooling cycles and characterization of its chemical composition and functional properties. The experiment was conducted by applying the autoclaving process at 121oC for 15 minutes followed by cooling at 4oC for 24 hours up to 5 times. Sample was taken from each cycle of autoclaving – cooling. The best treatment was the sample with the highest total soluble fiber and resistant starch content. The best sample will be determined its chemical composition and functional properties. This study used a one-way analysis of variance to subject the data according to Completely Randomized Design. Duncan’s Multiple Range Test was applied to determine significant differences among 5 treatment means at the 5% significance level. The highest value of total soluble fiber and resistant starch content was obtained from autoclaving-cooling cycles of 3 times. The treatment increased the soluble fiber and resistant starch by 14.37% and 18.34%, respectively, but decreased 14.41% insoluble fiber. The complex carbohydrates of white jack bean treated with autoclaving-cooling cycles of 3 times had chemical composition: 10.68% moisture content, 0.92% ash content, 0.02% fat content, 1.85% protein content, 97.20% carbohydrate content (by difference), 68.42% starch content, and 14.90 ppm HCN. It also had functional properties: 351.67% WHC, 115.67% OHC, 775.33% SC, 84.63 meq/kg CEC. The conclusion was the white jack bean carbohydrate complex treated with 3 times autoclaving-cooling cycles was the best treatment to produce the highest value of total soluble fiber and resistant starch content. We suggest to examine another autoclaving temperature and cooling time to compare the result.

In this study, cassava starch was modified using physical modification by ultrasonication. Ultrasonication, known as one of the advanced oxidation methods, is environmentally friendly. Modified starches using ultrasonication are still relatively lacking. This research aims to evaluate the stage of oxidation through carbonyl and carboxyl contents, amylose content, and physicochemical characteristics (swelling power, solubility, paste viscosity, brightness) of ultrasonicated starch. Ultrasonication was carried out in combination amplitude (60% and 80%) and process duration (10, 20, 30, and 40 minutes) consisting of eight combinations. The results showed that ultrasonication did not significantly affect the degree of oxidation. Ultrasonication has more effect on starch depolymerization, mainly on amylose content, solubility, and paste viscosity. Considering the issue of environmentally friendly modification that continues to be campaigned for, ultrasonication can be the method of choice for obtaining starch with the characteristics as needed.

Formulasi dan Karakteristik Bubur Kacang Merah (Phaseolus vulgaris L.) Instan dengan Pemanis Sukrosa, Isomalto-oligosakarida dan Fibercreme