ISOLASI PROTEIN KACANG MERAH DAN KACANG HIJAU MENGGUNAKAN METODE ASAM BASA DIKOMBINASIKAN DENGAN PROSES ENZIMATIS

Red beans (Phaseolus vulgaris L.) and greens beans (Phaseolus raditus L.) proteins contain high amount of essential amino acids lysine and leucine. The study aimed to determine the optimum conditions for protein isolation process from red beans and green beans flour to produce the highest protein content. Additionally, an enzymatic hydrolysis was aimed to produce isolates or protein concentrates of red beans and green beans with good digestibility. The research method used was the Response Surface Methodology (RSM) Box-Behnken Design with Design Expert 10. The variables used in this process were extraction temperature (30-50°C), extraction pH (8.50-9.50), and time extraction (30-60 minutes). The results showed that the optimum conditions for the extraction of red beans protein were extraction pH of 8.60, temperature of 30°C, and time of 30.1 minutes, with the resulting protein content of 86.88±1.38% with and a validity value of 0.91. Meanwhile, the optimum conditions for the green beans protein extraction process were extraction pH of 8.83, extraction temperature of 30°C, extraction time of 30 minutes which yielded protein content of 88.27±1.08% and a validity value of 0.97. Enzymatic hydrolysis using of 3% (w/w) bromelain enzyme on red bean and mung bean protein concentrate powder was able to increase protein digestibility by 15.61 and 14.51%, respectively.

Antioxidant Potential of Mung Bean (Vigna radiata) Albumin Peptides Produced by Enzymatic Hydrolysis Analyzed by Biochemical and In Silico Methods

The objective of this study was to investigate the biochemical antioxidant potential of peptides derived from enzymatically hydrolyzed mung bean (Vigna radiata) albumins using an 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging assay, a ferrous ion chelating assay and an oxygen radical absorbance capacity (ORAC) assay. Peeled raw mung bean was ground into flour and mixed with buffer (pH 8.3, 1:20 w/v ratio) before being stirred, then filtered using 3 kDa and 30 kDa molecular weight cut-off (MWCO) centrifugal filters to obtain albumin fraction. The albumin fraction then underwent enzymatic hydrolysis using either gastrointestinal enzymes (pepsin and pancreatin) or thermolysin. Peptides in the hydrolysates were sequenced. The peptides showed low ABTS radical-scavenging activity (90-100 μg ascorbic acid equivalent/mL) but high ferrous ion chelating activity (1400-1500 μg EDTA equivalent/mL) and ORAC values (>120 μM Trolox equivalent). The ferrous ion chelating activity was enzyme- and hydrolysis time-dependent. For thermolysin hydrolysis, there was a drastic increase in ferrous ion chelating activity from t = 0 (886.9 μg EDTA equivalent/mL) to t = 5 min (1559.1 μg EDTA equivalent/mL) before plateauing. For pepsin-pancreatin hydrolysis, there was a drastic decrease from t = 0 (878.3 μg EDTA equivalent/mL) to t = 15 (138.0 μg EDTA equivalent/mL) after pepsin was added, but this increased from t = 0 (131.1 μg EDTA equivalent/mL) to t = 15 (1439.2 μg EDTA equivalent/mL) after pancreatin was added. There was no significant change in ABTS radical scavenging activity or ORAC values throughout different hydrolysis times for either the thermolysin or pepsin-pancreatin hydrolysis. Overall, mung bean hydrolysates produced peptides with high potential antioxidant capacity, being particularly effective ferrous ion chelators. Other antioxidant assays that use cellular lines should be performed to measure antioxidant capacity before animal and human studies.

A ferrocene/imprinted polymer nanomaterial-modified carbon paste electrode as a new generation of gate effect-based voltammetric sensor

Herein, a carbon paste electrode, concurrently incorporated with ferrocene and a molecularly imprinted polymer nanomaterial (Fc-MIP-CP electrode), is introduced as an innovative sensing platform for the detection of thiamine.