Ultrasound and microwave assisted extraction of diosgenin from fenugreek seed and fenugreek-supplemented cookies

Fenugreek derived diosgenin as an emerging source for diabetic therapy

Diabetes is a chronic metabolic disease that endangers the entire body's tissues and organs. Diabetes impairs glucose and insulin regulation in the human body by causing pancreatic cell damage. Diabetes modifies pathways such as serine/threonine protein kinase (Akt) and Protein kinase C (PKC)/- glucose transporter 4 (GLUT4), peroxisome proliferator-activated receptor (PPAR) glucose absorption, and inhibits α-amylase and α-glucosidase, Sodium/glucose cotransporter 1 (SGLT-1), and Na+-K+-ATPase activity. Diabetes may also be caused by a decrease in the expression of sterol regulatory element binding protein 1 (SREBP-1) and its target genes, fatty acid synthase (FAS), stearoyl-CoA desaturase-1 (SCD-1), and acetyl-CoA carboxylase α (ACC), as well as a decrease in the levels of C/EBP homologous protein (CHOP), Caspase12, and Caspase3 proteins. Diabetes has long been linked to diseases of the cardiovascular, nervous, skeletal, reproductive, hepatic, ocular, and renal systems. Diosgenin, a steroidal compound derived from fenugreek, aids in the prevention of diabetes by altering cellular pathways in favor of healthy bodily functions. Diosgenin is a new nutraceutical on the market that claims to cure diabetes in particular. This article focuses on diosgenin extraction and purification, fenugreek bioactive compounds, pharmacological properties of diosgenin, mode of action of diosgenin to cure diabetes, and dosages.

Ultrasonic-assisted extraction of fenugreek flavonoids and its geographical-based comparative evaluation using green UHPLC-DAD analysis

BACKGROUND

This study, for the first time, reports a simultaneous determination of flavonoids; rutin (RT), quercetin (QT), luteolin (LT), and kaempferol (KF) in different origins of fenugreek seeds samples (N = 45) using a green UHPLC-DAD analysis METHODOLOGY: Ultrasound-assisted extraction (UAE) was employed to extract fenugreek flavonoids using different polarity solvents of n-hexane (n-hex), dichloromethane (DCM), and methanol (MeOH) RESULTS: The extract yield on an individual basis was observed in the range of 1.03-17.29 mg, with the highest yield (mg/sample) for the Egyptian sample (17.29 mg). The highest total extract yield (mg/origin) was observed for the Iranian sample (82.28 ± 5.38). The solvent with the highest extract yield (mg) was n-hex 169.35 ± 13.47, followed by MeOH 114.39 ± 12.27. The validated green UHPLC-DAD method resulted in a short runtime (9 min) with an accuracy of 97.86(±12.32)-101.37(±5.91), r2-values = 0.993-0.999, LOD = 2.09-4.48 ppm, and LOQ = 6.33-13.57 ppm for flavonoids analysis within the linearity range of 1-500 ppm. The general yield for flavonoids exhibited a descending order (ppm): RT (2924.55 ± 143.84) > QT (457.05 ± 34.07) > LT (82.37 ± 3.27) > KF (4.54 ± 0.00). The yield (ppm) for the flavonoids was more in MeOH solvent (3424.81 ± 235.44) constructing a descending order of MeOH > n-hex > DCM. For an individual flavonoid yield; MeOH was seen with an order of RT > QT > LT, n-hex (LT > QT), and DCM (RT > LT > QT). The statistical analysis of PCA (principle component analysis) revealed a widespread distribution of flavonoids in fenugreek seeds with a variance of 35.93% (PC1). Moreover, flavonoids extraction was prone to the nature and specificity of the solvent used (PC2: 33.34%) rather than the amount of the extract yield (P = 0.00). The K-mean cluster analysis showed the origins with higher flavonoids yield in appropriate solvent as I3M (Indian accession # 3 MeOH extract) with more QT amount, IR2M (Iranian accession # 2 MeOH extract) with more LT amount along with I2M (Indian accession # 2 MeOH extract) and Q2M (Qassim Saudi Arabia accession # 2 MeOH extract) containing high amount of RT. The outcomes are supported by KMO (Kaiser-Meyer-Olkin) and Bartlett's test value of 0.56 with X2-value of 191.87 (P = 0.00) CONCLUSION: The samples were effectively evaluated and standardized in terms of flavonoid amount suggesting a significant variation in fenugreek quality.

New alternatives from sustainable sources to wheat in bakery foods: Science, technology, and challenges

Ongoing research in the food industry is striving to replace wheat flour with new alternatives from sustainable sources to overcome the disease burden in the existing population. Celiac disease, wheat allergy, gluten sensitivity, or non-celiac gluten sensitivity are some common disorders associated with gluten present in wheat. These scientific findings are crucial to finding appropriate alternatives in introducing new ingredients supporting the consumer's requirements. Among the alternatives, amaranth, barley, coconut, chestnut, maize, millet, teff, oat, rye, sorghum, soy, rice flour, and legumes could be considered appropriate due to their chemical composition, bioactive profile, and alternatives utilization in the baking industry. Furthermore, the enrichment of these alternatives with proper ingredients is considered effective. Literature demonstrated that the flours from these alternative sources significantly enhanced the physicochemical, pasting, and rheological properties of the doughs. These flours boost a significant reduction in gluten proteins associated with food intolerance, in comparison with wheat highlighting a visible market opportunity with nutritional and organoleptic benefits for food producers. PRACTICAL APPLICATIONS: New alternatives from sustainable sources to wheat in bakery foods as an approach that affects human health. Alternatives from sustainable sources are important source of nutrients and bioactive compounds. Alternatives from sustainable sources are rising due to nutritional and consumer demand in bakery industry. New alternatives from sustainable sources improve physicochemical, pasting, and rheological properties of dough. Non-wheat-based foods from non-traditional grains have a potential to increase consumer market acceptance.

Recovery of Bioactive Compounds from Industrial Exhausted Olive Pomace through Ultrasound-Assisted Extraction

Simple Summary

Exhausted olive pomace (EOP) is the main residue of the pomace oil extraction industry, which is generated in large quantities and has limited applications. Thus, this study aimed to obtain bioactive compounds from EOP using ultrasound-assisted extraction as a potential first valorization step. Two types of devices were tested: bath- and probe-type UAE. The operational parameters were studied and optimized to maximize the antioxidant compounds. In particular, hydroxytyrosol was the main phenolic compound identified and its content was 5.16 mg/g EOP (bath-type UAE) and 4.96 mg/g EOP (probe-type UAE). Mannitol was also detected in the extract, 59.53 mg/g EOP (bath-type UAE) and 69.73 mg/g EOP (probe-type UAE). The results highlight the great potential EOP has as a source of bioactive compounds, with applicability in several sectors. Moreover, the probe-type UAE shows potential to be applied for obtaining these bioactive compounds in a continuous and faster manner.

Abstract

Exhausted olive pomace (EOP) is the main agro-industrial waste of the olive pomace extracting industries. It contains phenolic compounds and mannitol, so the extraction of these bioactive compounds should be considered as a first valorization step, especially if EOP is used as biofuel. Therefore, EOP was subjected to bath-type ultrasound-assisted extraction (UAE), and the effects of the acetone concentration (20–80%, v/v), solid load (2–15%, w/v), and extraction time (10–60 min) on the extraction of antioxidant compounds were evaluated according to a Box–Behnken experimental design. By means of the response surface methodology, the optimum conditions were obtained: 40% acetone, 8.6% solids, and 43 min. For all the extracts, the total phenolic content (TPC), flavonoid content (TFC), and antioxidant activity (DPPH, ABTS, and FRAP) were determined. With the aim of shortening the extraction time, a two-level factorial experiment design was also carried out using a probe-type UAE, keeping the solid load at 8.6% (w/v) and the acetone concentration at 40% (v/v), while the amplitude (30–70%) and the extraction time (2–12 min) were varied to maximize the aforementioned parameters. Finally, a maximum of phenolic compounds was reached (45.41 mg GAE/g EOP) at 12 min and 70% amplitude. It was comparable to that value obtained in the ultrasonic bath (42.05 mg GAE/g EOP), but, remarkably, the extraction time was shortened, which translates into lower costs at industrial scale. Moreover, the bioactive compound hydroxytyrosol was found to be the major phenolic compound in the extract, i.e., 5.16 mg/g EOP (bath-type UAE) and 4.96 mg/g EOP (probe-type UAE). Other minor phenolic compounds could be detected by capillary zone electrophoresis and liquid-chromatography–mass spectrometry. The sugar alcohol mannitol, another bioactive compound, was also found in the extract, and its content was determined. Thus, the use of this technology can support the valorization of this waste to obtain bioactive compounds, including mannitol, hydroxytyrosol, and other derivatives, before being applied for other uses.

Comparison of ultrasound and microwave assisted extraction of diosgenin from Trigonella foenum graceum seed

From the recent market trend, there is a huge demand for the bioactive compounds from various food matrices that could be capable enough to combat the emerging health effects in day-to-day life. Fenugreek is a well-known spice from ancient times for its medicinal and health benefits. In the present study, two methods of green extraction microwave (MAE) and ultrasound (UAE) assisted were studied in regard of extraction of fenugreek diosgenin. In this study, solvent type (acetone, ethanol, hexane and petroleum ether), solvent concentration (40, 60, 80 and 100%) and treatment time (1.5, 3.0, 4.5 and 6.0 min and 30, 40, 50 and 60 min for MAE and UAE method respectively) was varied to observe the effect of these parameters over extract yield and diosgenin content. The results of this study revealed that treatment time, type of solvent and its concentration and method adopted for extraction of diosgenin has significant effect. In relation with better yield extract and diosgenin content, the yield of fenugreek seed extract was 7.83% with MAE and 21.48% with UAE of fenugreek seed powder at 80% ethanol concentration at 6 and 60 min respectively. The content of diosgenin was observed in fenugreek seed powder extract was 35.50 mg/100 g in MAE and 40.37 mg/100 g in UAE with 80% ethanol concentration at 6 and 60 min respectively. The overall range of yield of fenugreek extract was varied from 1.04% to 32.48% and diosgenin content was 15.82 mg/100 g to 40.37 mg/100 g of fenugreek seed powder including both extraction methods. This study revealed that UAE would impose better ways for preparing fenugreek extract and observing diosgenin content from fenugreek seeds.

Ultrasound-Assisted Extraction of GAC Peel: An Optimization of Extraction Conditions for Recovering Carotenoids and Antioxidant Capacity

The peel of Gac fruit (Momordica cochinchinensis Spreng.), which is considered as waste of Gac processing, has been found to possess high levels of carotenoids and other antioxidants. This study aimed at determining the optimal conditions of an ultrasound-assisted extraction for recovering carotenoids and antioxidant capacity from Gac peel. A response surface methodology using the Box–Behnken design was employed to investigate the impact of extraction time, temperature and ultrasonic power on the recovery of total carotenoid and antioxidant capacity. The results showed that an extraction time of 76 min, temperature of 50 °C and ultrasonic power of 250 W were the optimal conditions for the extraction. The experimental carotenoid yield and antioxidant capacity obtained under the optimal extraction conditions were validated as 269 mg/100 g DW (dry weight) and 822 µM TE (Trolox equivalent)/100 g DW, respectively. These values were not significantly different from the values predicted by the models. The HPLC analysis for carotenoid composition showed that β-carotene, lycopene and lutein were the principal carotenoids of the extract, which constitute 86% of the total carotenoid content. Based on the obtained results, the ultrasound-assisted extraction using ethyl acetate under the above optimal conditions is suggested for the simultaneous recovery of carotenoids and antioxidant capacity from Gac peel.

Ultrasound-assisted extraction and bioaccessibility of saponins from edible seeds: quinoa, lentil, fenugreek, soybean and lupin

The efficient production of saponin-rich extracts is of increasing interest due to the bioactive properties that have being demonstrated for these compounds. However, saponins have a poor bioavailability. In this respect, the knowledge about the bioaccessibility of saponins as a first step before bioavailability has been scarcely explored. In this study, the production of ultrasound-assisted extracts of saponins from edible seeds (quinoa, soybean, red lentil, fenugreek and lupin) was carried out with ethanol, ethanol:water or water. Extraction yield, total saponin (TSC), fat and total phenolics content (TPC) were determined. Then, the bioaccessibility of saponins after the in vitro gastrointestinal digestion of the extracts was determined and the effect of TPC and fat in the extracts on bioaccessibility was evaluated. The highest saponin-rich extracts were obtained by ethanol, being fenugreek and red lentil the richest extracts (12% and 10%, respectively). Saponins from ethanol:water extracts displayed variable bioaccessibility (from 13% for fenugreek to 83% for lentil), but a bioaccessibility closer to 100% was reached for all ethanol extracts. Correlation studies showed that TPC of the extracts negatively affected the bioaccessibility of saponins, whereas fat of the extracts enhanced this parameter. As summary, ultrasound-assisted extraction is shown as an efficient method for obtaining saponin-rich extracts from edible seeds, being ethanol the most advantageous solvent due to the richness of saponins and the successful bioaccessibility from these extracts, likely caused by the co-extracted fat with ethanol. Regardless of the extracts, phenolic compounds or fat may hinder or enhance the bioaccessibility of saponins, respectively. Additionally, an adequate balance between saponins to lipids has shown to be relevant on such an effect.

Microwave-assisted extraction and ultrasound-assisted extraction for recovering carotenoids from Gac peel and their effects on antioxidant capacity of the extracts

The peel of Gac fruit (Momordica cochinchinensis Spreng.) contains high levels of bioactive compounds, especially carotenoids which possess significant antioxidant capacities. However, the peel of Gac is regarded as a waste from the production of carotenoid‐rich oil from Gac fruit. In this study, carotenoids of Gac peel were extracted by microwave‐assisted extraction (MAE) and ultrasound‐assisted extraction (UAE) using ethyl acetate as extraction solvent. The effect of extraction time and different levels of microwave and ultrasonic powers on the yield of total carotenoid and antioxidant capacity of the extracts were investigated. The results showed that an extraction at 120 W for 25 min and an extraction at 200 W for 80 min were the most effective for MAE and UAE of the Gac peel samples, respectively. The maximum carotenoid and antioxidant capacity yields of UAE were significantly higher than those of the MAE. The antioxidant capacity of extract obtained by the UAE was also significantly higher that of the conventional extraction using the same ratio of solvent to material. The results showed that both MAE and UAE could be used to reduce the extraction time significantly in comparison with conventional extraction of Gac peel while still obtained good extraction efficiencies. Thus, MAE and UAE are recommended for the improvement of carotenoid and antioxidant capacity extraction from Gac peel.