Bioactive peptides identification and nutritional status ameliorating properties on malnourished rats of combined eel and soy-based tempe flour

Nindy Sabrina; Mochammad Rizal; Fahrul Nurkolis; Hardinsyah Hardinsyah; Melvin Junior Tanner; William Ben Gunawan; Matthew Nathaniel Handoko; Nelly Mayulu; Nurpudji Astuti Taslim; Dwi Sari Puspaningtyas; Sutamara Lasurdi Noor; Vincentius Mario Yusuf; Happy Kurnia Permatasari; Son Radu

doi:10.3389/fnut.2022.963065

Bioactive peptides identification and nutritional status ameliorating properties on malnourished rats of combined eel and soy-based tempe flour

Front Nutr. 2022 Sep 28:9:963065. doi: 10.3389/fnut.2022.963065. eCollection 2022.

Authors

Affiliations

¹ Department of Nutrition, Dietetics, and Food, Faculty of Medicine, Nursing, and Health Sciences, Monash University, Melbourne, VIC, Australia.
² Nutrition Program, Faculty of Food Technology and Health, Sahid University of Jakarta, South Jakarta, Indonesia.
³ Division of Nutritional Sciences, Cornell University, Ithaca, NY, United States.
⁴ Department of Biological Sciences, Faculty of Sciences and Technology, State Islamic University of Sunan Kalijaga (UIN Sunan Kalijaga Yogyakarta), Yogyakarta, Indonesia.
⁵ Applied Nutrition, Faculty of Human Ecology, IPB University, Bogor, Indonesia.
⁶ Department of Nutrition, Faculty of Public Health, University of Indonesia, Depok, Indonesia.
⁷ Department of Nutrition Science, Faculty of Medicine, Diponegoro University, Semarang, Indonesia.
⁸ Nutrition and Food, Faculty of Medicine, Sam Ratulangi University, Manado, Indonesia.
⁹ Clinical Nutrition, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia.
¹⁰ Human Nutrition, Bloomberg School of Public Health, The Johns Hopkins University, Baltimore, MD, United States.
¹¹ Clinical and Public Health Nutrition Programme, University College London, London, United Kingdom.
¹² Department of Biochemistry and Biomolecular, Faculty of Medicine, Brawijaya University, Malang, Indonesia.
¹³ Department of Food Sciences, Universiti Putra Malaysia, Selangor Darul Ehsan, Malaysia.

Abstract

Background and aims: A combined eel and soy-based tempe (CEST) flour is rich in nutrients, especially its high amino acid content in which bioactive peptides (BPs) are expected to be found. Hence, this research aimed to identify the BPs of CEST flour and CEST supplementation's effect on improving nutritional status biomarkers by ameliorating serum protein, hemoglobin, and IGF-1 of malnourished rats.

Methods: CEST flour with a ratio of eel and soy-based tempe of 1:3.5 was produced by applying the oven drying method. Amino acid sequences from six BPs were analyzed using a protein sequencer and spectrometer-electrospray ionization (MS-ESI). A total of thirty malnourished male Rattus norvegicus aged 3-4 weeks were given low-protein (LP; 4% w/w protein) diet treatment for 4 weeks. Afterward, rats were divided into 3 groups of 10 rats. Group A and B remained on a low-protein diet for 4 weeks, receiving an LP diet and getting doses of CEST of 100 and 200 mg/kg BW, respectively, via oral. Group C or control was given a Normal-protein (NP) diet (23% w/w of protein) and was allowed to feed ad libitum during the trial period without a dose of CEST.

Results: Six bioactive peptides were found, with WMGPY being the most abundant, along with a DPPH radical scavenging activity of 5.0 mg/mL. The results showed that serum protein, hemoglobin, and IGF-1 of group B were significantly higher compared to groups A and C (p = 0.0021). CEST dose of 200 mg/kg BW was more effective to increase serum levels of protein (p = 0.0052), hemoglobin, and IGF-1 (p < 0.0001) compared to a 100 mg/kg BW dose.

Conclusion: This indicates that the CEST flour has six bioactive peptides, which may contribute to the improvement of nutritional status biomarkers. To establish its potential impact, a human clinical study is urgently needed.

Keywords: IGF-1; eel; hemoglobin; malnutrition; serum protein; tempe; undernutrition.