Covalent conjugation of Inca peanut albumin and polyphenols with different phenolic hydroxyl numbers through laccase catalysis to improve functional properties.

BACKGROUND: Enzymatic crosslinking is a method that can be used to modify Inca peanut albumin (IPA) using polyphenols, and provides desirable functionalities; however, the effect of polyphenol structures on conjugate properties is unclear. In this study, we selected four polyphenols with different numbers of phenolic hydroxyl groups [para-hydroxybenzoic acid (HBA), protocatechuic acid (PCA), gallic acid (GA), and epigallocatechin gallate (EGCG)] for covalent modification of IPA by enzymatic crosslinking, and explored the structure-function changes of the IPA-polyphenol conjugates. RESULTS: Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analysis showed that laccase successfully promoted covalent crosslinking of IPA with polyphenols, with the order of degree of conjugation as EGCG > GA > PCA > HBA, the IPA-EGCG conjugate showed the highest polyphenol binding equivalents (98.35 g kg-1 protein), and a significant reduction in the content of free amino, sulfhydryl, and tyrosine group. The oxidation of polyphenols by laccase forms quinone or semiquinone radicals that are covalently crosslinked to the reactive groups of IPA, leading to significant changes in the secondary and tertiary structures of IPA, with spherical structures transforming into dense lamellar structures. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging ability and emulsification stability of IPA-EGCG conjugates improved by almost 6-fold and 2.7-fold, respectively, compared with those of unmodified IPA. CONCLUSION: These data suggest that the higher the number of polyphenol hydroxyl groups, the higher the degree of IPA-polyphenol conjugation; additionally, enzymatic crosslinking can significantly improve the functional properties of IPA. © 2024 Society of Chemical Industry.

Physicochemical, Functional, and In Vitro Digestibility of Protein Isolates from Thai and Peru Sacha Inchi (Plukenetia volubilis L.) Oil Press-Cakes.

Proteins from Sacha inchi (SI) have been widely known for their health-benefiting properties. This study aimed to investigate the different protein isolates obtained from oil press-cakes of Thai and Peru SI. The protein content and protein recovery of Thai and Peru SI were estimated to be 93.27, 90.67%, and 49.15, 59.32%, respectively. The protein patterns of the Thai and Peru SI samples analyzed by SDS-PAGE showed glycoprotein as a major protein, with a molecular weight of 35 kDa. Both protein isolates (PI) showed water and oil holding capacities in the range of 2.97−3.09 g/g sample and 2.75−2.88 g/g sample, respectively. The emulsifying properties of the PI from Thai SI were higher than those of Peru (p < 0.05), while the foaming properties were not analogous to the emulsion properties. The Thai SI sample showed lower digestibility up to 120 min of in vitro digestion time than that of the Peru SI sample (p < 0.05). However, simulated in vitro pepsin digestion of Thai and Peru Si samples displayed hydrolyzed protein bands compared to trypsin digestion, which showed no protein patterns in both SI samples on a 4−20% gradient gel. These results suggest that the protein isolates from Thai and Peru SI exhibit marked variations in physical and techno-functional properties and have a high potential to be employed as plant-based protein additives for future non-animal-based protein-rich foods.

Sacha inchi (Plukenetia volubilis L.): An emerging source of nutrients, omega-3 fatty acid and phytochemicals.

Sacha inchi (Plukenetia volubilis) (SI) is an oleaginous plant producing oil and protein-rich seeds. It has been cultivated for centuries and is native to the tropical rainforest of the Amazon region of South America including parts of Peru and northwestern Brazil. At present, SI seeds are emerging as a potential source of macro- and micronutrients, α-linolenic acid and phytochemicals. This review attempts to elucidate the nutrients, phytonutrients, safety, toxicity, health benefits and food applications of SI seed. Recent scientific studies have associated the consumption of SI seed/oil with reduced risk of chronic inflammatory diseases. However, lack of awareness and in-depth understanding has resulted in it being neglected both at the consumer and industrial level. In all, SI is an underutilized and undervalued oleaginous crop which not only has the potential to mitigate food and nutritional insecurity but also offers humongous opportunities for the development of novel value-added food products.

Sacha inchi (Plukenetia volubilis L.)-from lost crop of the Incas to part of the solution to global challenges?

MAIN CONCLUSION: The underutilized, oleaginous crop Plukenetia volubilis L. has a remarkable lipid composition and a large potential for further domestication, alleviation of malnutrition, and integration into sustainable food production systems. Current global challenges include climate change, increasing population size, lack of food security, malnutrition, and degradation of arable lands. In this context, a reformation of our food production systems is imperative. Underutilized crops, or orphan crops, can provide valuable traits for this purpose, e.g., climate change resilience, nutritional benefits, cultivability on marginal lands, and improvement of income opportunities for smallholders. Plukenetia volubilis L. (Euphorbiaceae)-sacha inchi-is a 'lost crop' of the Incas native to the Amazon basin. Its oleaginous seeds are large, with a high content of ω-3, and -6 fatty acids (ca. 50.5, and 34.1%, of the lipid fraction, respectively), protein, and antioxidants. Culinarily, the seeds are nut-like and the crop has been associated with humans since Incan times. Research has particularly been undertaken in seed biochemistry, and to some extent in phylogeny, genetics, and cultivation ecology, but attention has been unevenly distributed, causing knowledge gaps in areas such as ethnobotany, allergenicity, and sustainable cultivation practices. Recently, seed size evolution and molecular drivers of the fatty acid synthesis and composition have been studied, however, further research into the lipid biosynthesis is desirable. Targeted breeding has not been undertaken but might be especially relevant for yield, sensory qualities, and cultivation with low environmental impact. Similarly, studies of integration into sustainable management systems are of highest importance. Here, present knowledge on P. volubilis is reviewed and a general framework for conducting research on underutilized crops with the aim of integration into sustainable food production systems is presented.

Safety assessment of Plukenetia volubilis (Inca peanut) seeds, leaves, and their products.

Plukenetia volubilis or Inca peanut is a promising plant with high economic value. Its seeds can be pressed for oil production or roasted and served as a snack, while the dried leaves can be used to make a kind of tea. Although the oil from the cold-pressed seeds has been proven to be safe for human consumption, little information is known about the other parts of the plant regarding safety. Thus, the aim of this study was to investigate the naturally occurring phytotoxins, including saponins, total alkaloids, and lectins in fresh and roasted Inca peanut seeds and leaves. In addition, cytotoxicity on several normal cell types including human peripheral blood mononuclear cells, human embryonic kidney cells, human hepatic stellate cells, and mouse fibroblasts as well as in vivo mutagenic properties was studied. This study showed that fresh Inca peanut seeds and leaves contain saponins, alkaloids, and lectins. However, roasting enables the reduction in alkaloids, saponins, and possibly lectins, suggesting that these phytotoxins become unstable under heat. Furthermore, Inca peanut seeds and leaves, especially after roasting, are safe to a variety of normal cell lines and do not induce DNA mutations in Drosophila expressing high biotransformation system. In conclusion, the data in this study indicated that high and chronic consumption of fresh seeds and leaves should be avoided. Heat processing should be applied before the consumption of Inca peanut seeds and leaves in order to reduce phytotoxins and potential health risks.

Structural, functional properties and immunomodulatory activity of isolated Inca peanut (Plukenetia volubilis L.) seed albumin fraction.

This work aimed to determine the structural, functional properties and immunomodulatory activity of an albumin fraction isolated from Inca peanut seed (AF-IPS). Structural characterization revealed that AF-IPS contains two polypeptides with molecular weight ranges of 25-45 and 10-15 kDa. AF-IPS is mainly composed of α-helix, ß-sheet, and ß-turn secondary structures. Differential scanning calorimetry analysis indicated that the denaturation temperature of AF-IPS at room temperature is 101.93 °C. AF-IPS possessed excellent protein solubility (63.0%), water holding capacity (1.59 g/g), foaming (350.2%) and emulsifying (13.0 mL/g) ability. Heat treatment improved protein solubility, oil holding capacity, and foaming and emulsifying ability. AF-IPS exhibited immunomodulatory activity by stimulating the proliferation and enhancing the TNF-α secretion of splenic lymphocytes, and through increasing the cellular lysosomal enzyme and pinocytic activities, and by moderately promoting the NO and H2O2 production of RAW264.7 cells. Our findings indicated that AF-IPS has potential applications in functional and pharmaceuticals foods.

COMPOSICIÓN DE ÁCIDOS GRASOS DE SACHA INCHI (Plukenetia volúbilis Linneo) Y SU RELACIÓN CON LA BIOACTIVIDAD DEL VEGETAL / FATTY ACID COMPOSITION OF INCA PEANUT (Plukenetia volúbilis Linneo) AND ITS RELATIONSHIP WITH VEGETAL BIOACTIVITY

Omega and unusual fatty acids were evaluated from ethanol extracts of roots and leaves ofPlukenetia volúbilis L. were evaluated. Seed oil was obtained by soxhlet and bioreactor; the fatty acids were determined and characterized by gas chromatography coupled to mass spectrometry (GLC-MS). Also, antioxidant activity was evaluated using ABTS/HRP enzymatic. Fatty acid in seed oil was beyond 80%. Meanwhile, the main unusually fatty acids in leaves and roots are ciclopropenic acids. The phytocompounds, omega and functional fatty acids could be responsible for the lipophilic antioxidant activity in leaves.

A partir de extractos etanólicos de hojas y raíces de Plukenetia volúbilis L, se evaluó la presencia de ácidos grasos omega (FAc) y funcionales. El aceite de las semillas de la planta, extraído por Soxhlet y a través de un biorreactor, fue caracterizado físicamente, se le determinó el perfil lipídico mediante cromatografía de gases acoplada a espectrometría de masas (CG-EM) y, se evaluó el potencial antioxidante (ABTS-HRP). El análisis dejó ver que el aceite del vegetal contiene ácidos grasos poliinsaturados en una proporción mayor al 80%. Los extractos de hojas y raíces mostraron principalmente ácidos de tipo ciclo-propénico. Tanto los fitocompuestos como los ácidos grasos omega y funcionales parecen estar asociados con la actividad antioxidante de las hojas.