A metabolomics approach to evaluate post-fermentation enhancement of daidzein and genistein in a green okara extract.

BACKGROUND: Okara is a major agri-industrial by-product of the tofu and soymilk industries. Employing food-wastes as substrates for the green production of natural functional compounds is a recent trend that addresses the dual concepts of sustainable production and a zero-waste ecosystem. RESULTS: Extracts of unfermented okara and okara fermented with Rhizopus oligosporus were obtained using ethanol as extraction solvent, coupled with ultrasound sonication for enhanced extraction. Fermented extracts yielded significantly better results for total phenolic content (TPC) and total flavonoid content (TFC) than unfermented extracts. A qualitative liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) analysis revealed a shift from glucoside forms to respective aglycone forms of the detected isoflavones, post-fermentation. Since the aglycone forms have been associated with numerous health benefits, a quantitative high-performance liquid chromatography (HPLC) analysis was performed. Fermented okara extracts had daidzein and genistein concentrations of 11.782 ± 0.325 µg mL-1 and 10.125 ± 1.028 µg mL-1 , as opposed to that of 6.7 ± 2.42 µg mL-1 and 4.55 ± 0.316 µg mL-1 in raw okara extracts, respectively. Lastly, the detected isoflavones were mapped to their metabolic pathways, to understand the biochemical reactions triggered during the fermentation process. CONCLUSION: Fermented okara may be implemented as a sustainable solution for production of natural bioactive isoflavonoids genistein and daidzein. © 2021 Society of Chemical Industry.

Medium-term outcomes of converting laparoscopic adjustable gastric band to Roux-en-Y gastric bypass in patients with body mass index <35 kg/m2: a uniquely Australian perspective.

BACKGROUND: The rates of primary laparoscopic adjustable gastric banding (LAGB) have declined in the last 5 years due to band removal secondary to complications and the subsequent weight regain that requires revisional procedures. OBJECTIVES: This study aimed to present medium-term weight loss results and the safety profile of converting LAGB to Roux-en-Y gastric bypass in patients with body mass index (BMI) <35.0 kg/m2 who presented with LAGB intolerance or complications. Many health services do not permit such procedures on low BMI patients. SETTINGS: Single-surgeon series, including public and private practice, Brisbane, Australia. METHOD: A prospectively maintained database was reviewed and retrospectively analyzed for LAGB patients with a BMI <35.0 kg/m2 who underwent conversion to Roux-en-Y gastric bypass by a single surgeon. Indications for conversion, weight loss data, and early (30 d postoperative) and late complications were recorded with follow-up out to 5 years. RESULTS: One hundred thirty-two adult patients with a BMI <35.0 kg/m2 underwent conversion from 2009 to 2016. The main indications for conversion were reflux and band complications. Median BMI at bypass was 32.8 kg/m2 (23.1-35.0). Median percentage excess weight loss was 77%, 90%, 73%, 47%, 49%, and 44% at 1, 2, 3, 4, and 5 years, respectively among patients who were eligible and present at follow-up. Median BMI was <30.0 kg/m2 (29.1-40.9) at 5 years with only 1 subject exceeding >35.0 kg/m2. Mortality was 0%. Early morbidity occurred in 31.8% of patients. The most common late complication was gastrojejunostomy stricture requiring endoscopic dilation. CONCLUSIONS: In combination with our 2014 study showing morbidity data in the short-term period being comparable to patients with BMI >35.0 kg/m2, our study demonstrates that converting LABG to Roux-en-Y gastric bypass in low BMI patients is a feasible and safe option that avoids weight regain and maintains adequate weight loss at 5 years, with acceptable morbidity and no mortality.

Characterization and in Vitro Bioactivity of Green Extract from Fermented Soybean Waste.

Extracts were extricated from raw okara and okara fermented with Rhizopus oligosporus using a clean, green protocol; water was used as the extraction solvent and coupled with ultrasound assistance for enhanced extraction. In vitro anti-oxidant analyses for antioxidant potential and capacity, superoxide scavenging activity, and nitric oxide scavenging activity validated that fermented okara yielded superior bioactive performance compared to raw okara. Fermented okara extracts showed no toxicity to erythrocytes and successfully prevented induced haemolysis. After 48 h incubation at the highest tested concentration (100 mg/mL), fermented okara extracts could inhibit HepG2 cells by 48.47 ± 5.28%, which was significantly different from their effects on NIH 3T3 cells. Gas chromatography-mass spectrometry characterization of extracts validated amino acids to be the chief fraction responsible for the detected bioactivity of the fermented okara extract. The results derived in this study open up the possibility that biofermented okara extract may be a potential novel sustainable nutraceutical.

Analysis of Improved Nutritional Composition of Potential Functional Food (Okara) after Probiotic Solid-State Fermentation.

Okara is a major agro-waste, generated as a byproduct from the soymilk and tofu industry. Since okara has a high nutritive value, reusing it as a substrate for solid state biofermentation is an economical and environmental friendly option. Rhizopus oligosporus and Lactobacillus plantarum were the probiotic FDA-approved food-grade cultures used in this study. The study revealed that biofermenting okara improves its nutritional composition. It was found that the metabolomic composition (by GC-MS analysis) and antioxidant activity (by DPPH test) improved after the microbial fermentations. Of the two, okara fermented with R. oligosporus showed better results. Further, the metabolites were traced back to their respective biosynthesis pathways, in order to understand the biochemical reactions being triggered during the fermentation processes. The findings of this entire work open up the possibility of employing fermented okara as a potential functional food for animal feed.