Bioactive Compounds in Velvet Bean Seeds: Effect of Certain Indigenous Processing Methods

Germination effects on the physicochemical properties and sensory profiles of velvet bean (Mucuna pruriens) and soybean tempe

Introduction

Previous studies have shown that the velvet bean, an indigenous legume in Indonesia, possesses high protein content and bioactive compounds. However, the utilization of velvet beans in tempe production remains underexplored.

Methods

This study aims to address this research gap by investigating the physicochemical properties and sensory profiles of tempe made from velvet beans, both individually and in combination with soybean. The study involved the production of tempe using germinated and non-germinated velvet bean, soybean, and a soy-velvet bean combination (61:39% ratio). Physicochemical analyses, including hardness, firmness, colour, antioxidant capacity, proximate, pH, and titratable acidity, were conducted. Hedonic rating and Check-All-That-Apply (CATA) tests were also performed to assess the sensory attributes of fresh and fried tempe.

Results and discussion

Germination treatment of velvet bean resulted in tempe with reduced hardness, firmness, antioxidant capacity, and pH levels compared to non-germinated velvet bean tempe. However, velvet bean tempe exhibited a darker colour, higher antioxidant capacity, higher pH levels, and lower titratable acidity compared to soybean tempe and soy-velvet bean combination tempe. The protein content in velvet bean tempe was found to be below the required threshold of 15%. Hedonic rating tests revealed that fresh and fried velvet bean tempe received lower scores than other samples. CATA tests identified specific sensory attributes essential for fresh and fried tempe, including beany aroma, white colour, nutty aroma, golden brown colour, solid and crunchy texture, umami taste, and nutty aftertaste. These findings provide valuable insights into the potential applications of velvet beans in tempe production and emphasize the significance of considering germination as a factor affecting the quality and sensory attributes of tempe.

Culture matters: A systematic review of antioxidant potential of tree legumes in the semiarid region of Brazil and local processing techniques as a driver of bioaccessibility

Ethnobotanical studies report that human populations from the Brazilian Caatinga biome use tree legumes (Fabaceae) with medicinal and food purposes. Our study provides a systematic review of the available published information concerning the antioxidant potential of Hymenaea courbaril L. (jatobá), Libidibia ferrea (Mart. Ex Tul.) L.P.Queiroz (jucá), and Dioclea grandiflora Mart. Ex Benth. (mucunã). Furthermore, in this paper, we infer the possible effects of local processing techniques applied to these plants on their antioxidant potential. In order to achieve these goals, we reviewed 52 articles, including studies from ethnobiology (n = 17), chemistry (n = 32), and food studies testing antioxidant activity (n = 17), excluding 14 repetitions. We found that these legume species can inhibit the formation of free radicals and this potential action varies among different parts of the plant. Probably, the presence of phenolic compounds such as phenolic acids and flavonoids, which are not uniformly distributed in the plants, explain their antioxidant activity. Local processing techniques (i.e., roasting, milling) affect the bioaccessibility of antioxidant components of tree legumes, inducing both positive and negative effects. However, studies about the antioxidant potential did not consider local processing techniques in their analyses. Our study highlights that culture is a fundamental driver of nutritional and pharmacological outcomes related to edible resources since it determines which parts of the plant people consume and how they prepare them. Hence, ignoring cultural variables in the analysis of antioxidant activity will produce inaccurate or wrong scientific conclusions.

Methanolic extracts of a selected Egyptian Vicia faba cultivar mitigate the oxidative/inflammatory burden and afford neuroprotection in a mouse model of Parkinson's disease

Vicia faba L. is a legume from the family Fabaceae. Ancient Egyptians consumed fava beans thousands of years ago and they are still one of the most popular foods in Egypt. The current study examined the anti-Parkinson effect of 80% methanolic extracts of seeds or sprouts of the fava 'Sakha 3 'cultivar which has been selected based on the total phenol content among three cultivars tested. In addition, the extracts were characterized by reversed-phase high-performance liquid chromatography coupled with diode array detection and quadrupole-time-of-flight-mass spectrometry (RP-HPLC-DAD-QTOF-MS). Three doses (200, 400, and 600 mg/kg) of 80% methanol extracts of seeds or sprouts of the Sakha 3 cultivar were evaluated in rotenone-Parkinsonian mice from behavioral, biochemical, and histopathological aspects. The extract of fava sprouts (600 mg/kg dose) showed the most beneficial effect. It improved motor activity, enhanced striatal dopamine level, and decreased the striatal malondialdehyde, as well as the expression of the inflammatory markers, compared with the rotenone control group and groups receiving lower therapeutic doses of the extracts or L-Dopa. In addition, these findings were supported by a histopathological investigation which indicated that mice treated with the 600-mg/kg dose of the sprout extract showed a low number of degenerated neurons. The application of RP-HPLC-DAD-QTOF-MS and mass/mass spectroscopy enabled the metabolic profiling of the sprouts and seeds of the 'Sakha 3' cultivar. It is obvious that germination increased the amounts of phenolic acids, saponins, and aromatic amino acids, together with a dramatic increase in flavonoids. In conclusion, the 80% methanolic extract of sprouts of the fava "Sakha 3" cultivar may be a promising candidate for treating Parkinsonism if appropriate safety data are available.