Extraction and characterization of proteins from banana (Musa Sapientum L) flower and evaluation of antimicrobial activities

Plant-based proteins: advanced extraction technologies, interactions, physicochemical and functional properties, food and related applications, and health benefits

Even though plant proteins are more plentiful and affordable than animal proteins in comparison, direct usage of plant-based proteins (PBPs) is still limited because PBPs are fed to animals as feed to produce animal-based proteins. Thus, this work has comprehensively reviewed the effects of various factors such as pH, temperature, pressure, and ionic strength on PBP properties, as well as describes the protein interactions, and extraction methods to know the optimal conditions for preparing PBP-based products with high functional properties and health benefits. According to the cited studies in the current work, the environmental factors, particularly pH and ionic strength significantly affected on physicochemical and functional properties of PBPs, especially solubility was 76.0% to 83.9% at pH = 2, while at pH = 5.0 reduced from 5.3% to 9.6%, emulsifying ability was the lowest at pH = 5.8 and the highest at pH 8.0, and foaming capacity was lowest at pH 5.0 and the highest at pH = 7.0. Electrostatic interactions are the main way for protein interactions, which can be used to create protein/polysaccharide complexes for food industrial purposes. The extraction yield of proteins can be reached up to 86-95% with high functional properties using sustainable and efficient routes, including enzymatic, ultrasound-, microwave-, pulsed electric field-, and high-pressure-assisted extraction. Nondairy alternative products, especially yogurt, 3D food printing and meat analogs, synthesis of nanoparticles, and bioplastics and packaging films are the best available PBPs-based products. Moreover, PBPs particularly those that contain pigments and their products showed good bioactivities, especially antioxidants, antidiabetic, and antimicrobial.

Impact of pH on pea protein-hydroxypropyl starch hydrogel based on interpenetrating network and its application in 3D-printing

Improving the mechanical and 3D printing performance of pea protein (PeaP) hydrogels contributes to the development of innovative plant-based gel products. Herein, we proposed a strategy for constructing PeaP-hydroxypropyl starch (HPS) interpenetrating network hydrogels, in which the structure, strength, and 3D printing properties of the hydrogels were regulated by changing pH. Results showed that pH significantly affected the gelation process of PeaP/HPS hydrogels. The hydrogels formed a lamellar structure at pH 3, a granule aggregation network structure at pH 5, porous structures at pH 7 and 9, and a honeycomb structure at pH 11. The strength of hydrogels formed at different pH values had the following order: pH 3 ＞pH 11 ＞ pH 7 ＞pH 9 ＞pH 5. The storage modulus (G') of the hydrogel at pH 3 was up to 4149 Pa, but only 695 Pa at pH 5. Moreover, hydrogel at pH 3 had the best self-recovery of 55%. 3D printed objects from gel inks at pH 3 exhibited high structural integrity and fidelity at 60 °C. Gelling force analysis indicated hydrogen bonds were the dominant interaction within all hydrogels. Overall, this study suggested that PeaP/HPS hydrogel formed at pH 3 possessed the most excellent mechanical properties and 3D printing capabilities, which may provide insights into the development of novel PeaP-based gel food ingredients and promote the application of PeaP in the food industry.

The Valorization of Banana By-Products: Nutritional Composition, Bioactivities, Applications, and Future Development

Bananas are among the world’s main economic crops and one of the world’s most-selling fresh fruits. However, a great deal of waste and by-products is produced during banana harvesting and consumption, including stems, leaves, inflorescences, and peels. Some of them have the potential to be used to develop new foods. Furthermore, studies have found that banana by-products contain many bioactive substances that have antibacterial, anti-inflammatory, and antioxidant properties and other functions. At present, research on banana by-products has mainly focused on various utilizations of banana stems and leaves, as well as the extraction of active ingredients from banana peels and inflorescences to develop high-value functional products. Based on the current research on the utilization of banana by-products, this paper summarized the composition information, functions, and comprehensive utilization of banana by-products. Moreover, the problems and future development in the utilization of by-products are reviewed. This review is of great value in expanding the potential applications of banana stems, leaves, inflorescences, and peels, which will not only help to reduce waste of agricultural by-product resources and ecological pollution but will also be useful for the development of essential products as alternative sources of healthy food in the future.

Synergistic Action of Multiple Enzymes Resulting in Efficient Hydrolysis of Banana Bracts and Products with Improved Antioxidant Properties

This study investigated the effect of enzymatic hydrolysis of banana bracts from different varieties (Maçã, Nanica and Prata) using pectinase, protease and cellulase (singly or in combinations) on their antioxidant properties. The results showed that the antioxidant properties and total phenolic compounds (TPC) of extracts increased after the enzymatic treatment with a clear synergistic effect between the different enzymes. The ternary mixture of pectinase, protease and cellulase resulted in increases of 458% and 678% in TPC content for extracts obtained from Maçã and Nanica varieties and up to 65% in antioxidant properties of those produced from Prata variety compared to the non-hydrolyzed samples. In general, the extracts obtained from the Prata variety showed the highest levels of TPC, as well as antioxidant activity, as follows: 14.70 mg GAE g−1 for TPC, 82.57 µmol TE g−1 for ABTS, 22.26 µmol TE g−1 for DPPH and 47.09 µmol TE g−1 for FRAP. Phenolic compounds identified by HPLC in extracts included ρ-coumaric, ferulic, sinapic and vanillic acids and the flavonoid rutin. This study reported for the first time the enzymatic treatment applied to banana bracts as a promising method to release antioxidant compounds, offering a new opportunity to explore these residues as a source of molecules with high added value through an environmentally friendly and safe process.

The effect of banana blossom on growth performance, immune response, disease resistance, and anti-hypothermal stress of Macrobrachium rosenbergii

Banana (Musa acuminata) blossom contains high nutritional value and bioactive compounds. In this study, Macrobrachium rosenbergii were fed with diets containing banana blossom powder (BBP) at 10 and 20 g kg^-1, hot-banana blossom (BBH) extract at 10 and 20 g kg^-1, and the basal diet for 56 days. The growth performance, physiological response and immune parameters were evaluated. The results showed that a significantly higher percentage weight gain (PWG) and percentage length gain (PLG) in prawns fed with BBH diet. The feed efficiency (FE) significantly increased in prawns fed BBP. The prawn fed both BBH and BBP diet showed higher survival rate than control group. The prawn fed with BBH showed a significant increase in total haemocyte count (THC) and different haemocyte count (DHC), whereas phenoloxidase (PO) activity and respiratory bursts (RBs) significant increase in prawns fed both BBP and BBH diet. Furthermore, M. rosenbergii fed with both BBP and BBH diets showed significantly higher phagocytic activity and clearance efficiency against Lactococcus garvieae infection. At the end of the 56 days of feeding trial, the susceptibility of prawns to L. garvieae infection and hypothermal (18 °C) stress were evaluated. The results showed that prawns fed BBH diets had a significantly higher survival rate against L. garvieae than those of fed with the basal diet. Anti-hypothermal stress was observed in prawns fed both BBP and BBH diets showing no significant difference in haemolymph glucose in prawns subjected to 18 °C and 28 °C, whereas the norepinephrine level in haemolymph of prawns fed with BBH diets subjected to 18 °C was significantly lower than in prawns subjected to 28 °C. In summary, we recommend addition of hot-banana blossom extract to the diet of M. rosenbergii at 20 g kg^-1 to promote growth performance, improve physiological function, enhance immunity, increase anti-hypothermal stress, and to increase resistance against L. gavieae.

Edible Flowers: Antioxidant Compounds and Their Functional Properties

Edible flowers have been widely consumed for ages until now. The attractive colors and shapes, exotic aroma, and delightful taste make edible flowers very easy to attain. Moreover, they also provide health benefits for consumers due to the unique composition and concentration of antioxidant compounds in the matrices. Knowing the bioactive compounds and their functional properties from edible flowers is necessary to diversify the usage and reach broader consumers. Therefore, this reported review could be useful for functional product development, engaging the discussed edible flowers. We present a comprehensive review of edible flower composition and the functional properties of their antioxidant compounds, mainly phenolics.

Comparative Metabolic Profiling in Pulp and Peel of Green and Red Pitayas (Hylocereus polyrhizus and Hylocereus undatus) Reveals Potential Valorization in the Pharmaceutical and Food Industries

Pitaya (Hylocereus genus) is a popular plant with exotic and nutritious fruit, which has widespread uses as a source of nutrients and raw materials in the pharmaceutical industry. However, the potential of pitaya peel as a natural source of bioactive compounds has not yet fully been explored. Recent advances in metabolomics have paved the way for understanding and evaluating the presence of diverse sets of metabolites in different plant parts. This study is aimed at exploring the diversity of primary and secondary metabolites in two commercial varieties of pitaya, i.e., green pitaya (Hylocereus undatus) and red pitaya (Hylocereus polyrhizus). A total of 433 metabolites were identified using a widely targeted metabolomic approach and classified into nine known diverse classes of metabolites, including flavonoids, amino acids and its derivatives, alkaloids, tannins, phenolic acids, organic acids, nucleotides and derivatives, lipids, and lignans. Red pitaya peel and pulp showed relatively high accumulation of metabolites viz. alkaloids, amino acids and its derivatives, and lipids. Differential metabolite landscape of pitaya fruit indicated the presence of key bioactive compounds, i.e., L-tyrosine, L-valine, DL-norvaline, tryptophan, γ-linolenic acid, and isorhamnetin 3-O-neohesperidoside. The findings in this study provide new insight into the broad spectrum of bioactive compounds of red and green pitaya, emphasizing the valorization of the biowaste pitaya peel as raw material for the pharmaceutical and food industries.

Enhanced yield of Scenedesmus obliquus biomacromolecules through medium optimization and development of microalgae based functional chocolate

The freshwater green microalga Scenedesmus obliquus was cultivated to enhance the contents of proteins, carbohydrates and lipids by using Box-Behnken experimental design. S. obliquus was cultured under phototrophic conditions by using Bold's Basal Medium with different cultivation parameters including pH (7, 8 and 9), salinity (10, 30 and 50 mM), and nitrogen source (0.125, 0.5 and 1 g/L). The highest biomass yield (64.9 ± 0.94 mg/L/day) was obtained by using optimized medium at a salinity concentration of 30 mM (w/v), and nitrogen sources of 0.125 g/L. The maximum content of protein, lipid and carbohydrates from S. obliquus optimized medium were 342.19 ± 0.28 mg/g, 241.41 ± 4.32 mg/g and 288.05 ± 1.12 mg/g of dry wt. respectively. The amino acid and fatty acid analysis of S. obliquus biomass indicated the presence of significant amount of essential amino acids and essential fatty acids. Furthermore, chocolate crispy bar was developed by fortification with encapsulated freeze-dried S. obliquus and evaluated for its oxidative stability and sensory analysis. The chocolate fortified with microalgae can be a potential source of essential fatty acids and amino acids in addition to other bioactive compounds.