Compositional variation in β-carotene content, carbohydrate and antioxidant enzymes in selected banana cultivars

Antioxidant and Anti-inflammatory Properties of the Two Varieties of Musa acuminata: An In Vitro Study

Background Free radicals are involved in the process of carcinogenesis. Conventional antioxidants and anti-inflammatory drugs have the disadvantages of side effects and high costs. Banana peel contains phenolic and non-phenolic antioxidants that are pivotal in removing inflammatory components by inhibiting reactive oxygen species (ROS), protecting protease inhibitors from oxidative damage, and preventing fibroblast degradation which protects the body against the ill effects of free radicals. Aim and objectives The present study aimed to evaluate the potential antioxidant and anti-inflammatory activity of peel extracts of the Musa acuminata Red Dacca(red banana) and Musa acuminata Colla (rasthali). Materials and methods The procured unripe peels of red bananas and rasthali bananas were dried, ground into powder, and used to create aqueous and alcoholic extracts. The aqueous extract was made by dissolving 5 grams of peel powder in 25 ml of distilled water, while the alcoholic extract was prepared by heating ethanol to 100°C for 30 minutes. The extracts were combined, shaken for 24 hours, filtered, and stored at 4°C. Following extract preparation, 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, hydrogen peroxide (H2O2) assay, bovine serum albumin (BSA) denaturation assay, and egg albumin (EA) denaturation assay were performed to evaluate the antioxidant and anti-inflammatory properties. The assays were performed in varying concentrations for the prepared extracts of red banana and rasthali and the 1:1 ratio combination extract of both varieties. The obtained data were tabulated and statistically tested using the IBM SPSS Statistics for Windows, Version 22.0 (Released 2013; IBM Corp., Armonk, New York, United States) by the Kruskal-Wallis test with the statistical significance set at p≤0.05. Results Results highlighted variations in the antioxidant and anti-inflammatory properties of the banana peel extracts and the standard used in all the assays, but there was no statistically significant difference between the extracts and the standard (p>0.05). There was an increase in the antioxidant and anti-inflammatory activity with an increase in the concentration of both the extracts and the standard. The 1:1 ratio combination extract showed the highest antioxidant property among the banana extracts in the majority of the concentrations in the DPPH assay, whereas the rasthali extract showed the same even more than the standard in the H2O2 assay. The rasthali extract showed the highest anti-inflammatory property in all the concentrations in the BSA assay, and the 1:1 ratio combination extract showed the same in the EA assay. Conclusion The banana peel extracts showed comparable antioxidant and anti-inflammatory properties with that of the standard in all the assays with no statistically significant difference. There was a rising trend in the properties with an increase in their concentration. Red banana and rasthali peel extracts, either individually or in combination, could be a promising, effective, and cost-effective alternative or adjunct to the currently available antioxidant medications.

Physicochemical properties and sensory evaluation of high energy cereal bar and its consumer acceptability

This research aims to study the physicochemical and sensory evaluation of high energy cereal bars (HCB) and their consumer acceptability using logistic regression. The HCB was prepared and formulated under using a mixture design (d-optimal) experiment with three centerpoints, namely, cereals (60-66%) fruits (14-20%), and sweeteners (20-26%). The regression analysis indicated that the three main ingredients affected physicochemical properties (color value, hardness, and stickiness), chemical properties (aw, total carbohydrate, gross energy, reducing sugar, non-reducing sugar, and total carotenoid), and sensory properties. The optimum content of cereals, fruits, and sweeteners for HCB was found to be 60.45%, 19.55%, and 20%. This indicates that puffed rice, roasted nuts, cereal seed, mixed fruits, corn syrup, and honey can provide high consumer product acceptance and purchase intention for a cereal bar and can be used to develop a high-energy cereal bar product desirable for the consumer market.

Influence of food hydrocolloids on the structural, textural and chemical characteristics of low-fat banana chips

Banana chips are gaining popularity as a deep-fried product for its unique taste and flavour. This study is aimed to investigate the effect of hydrocolloids on oil absorption, physico-chemical and sensory properties of banana chips from two different varieties (var. Popoulu and var. Nendran), when fried at 180 °C for 3 min. The reduction in oil content was about 15%-35% and 19%-30% for hydrocolloid treated Popoulu and Nendran chips, respectively. The Free fatty acid content (FFA) of hydrocolloid treated banana chips was lower than that of untreated chips. The peroxide value (PV) values of all samples fell below 2 meq oxygen kg^-1. CMC pre-treated banana chips were crispier than other formulations on both the varieties. Microscopic analysis showed the improved cellular integrity without large void spaces in hydrocolloid treated banana chips. PCA analyses elucidated that variables such as physical appearance, colour, crispiness, after taste, overall acceptability contributed positively, whereas hardness and sogginess contributed negatively to the correlation among the variables. From the chemical and sensory attributes, 0.5% CMC treated Popoulu chips and 1% CMC treated Nendran chips is recommended to produce chips with lower oil content.

Differential accumulation of β-carotene and tissue specific expression of phytoene synthase (MaPsy) gene in banana (Musa sp) cultivars

An experiment was conducted with twelve major Indian banana cultivars to investigate the molecular relationship between the differential accumulation of β-carotene in peel and pulp of the banana fruit and carotenoid biosynthetic pathway genes. The high performance liquid chromatography showed that all banana cultivars accumulated two-three fold more β-carotene in non-edible portion of the banana fruit. However, Nendran, a famous orange fleshed cultivar of South India, had high β-carotene content (1362 µg/100 g) in edible pulp. The gene encoding Musa accuminata phytoene synthase (MaPsy) was successfully amplified using a pair of degenerate primers designed from Oncidium orchid. The deduced amino acid sequences shared a high level of identity to phytoene synthase gene from other plants. Gene expression analysis confirmed the presence of two isoforms (MaPsy1 and MaPsy2) of MaPsy gene in banana fruits. Presence of two isoforms of MaPsy gene in peel and one in pulp confirmed the differential accumulation of β-carotene in banana fruits. However, Nendran accumulated more β-carotene in edible pulp due to presence of both the isoforms of MaPsy gene. Thus, carotenoid accumulation is a tissue specific process strongly dependent on differential expression pattern of two isoforms of MaPsy gene in banana.

Comparative Transcriptome Analysis Reveals the Influence of Abscisic Acid on the Metabolism of Pigments, Ascorbic Acid and Folic Acid during Strawberry Fruit Ripening

A comprehensive investigation of abscisic acid (ABA) biosynthesis and its influence on other important phytochemicals is critical for understanding the versatile roles that ABA plays during strawberry fruit ripening. Using RNA-seq technology, we sampled strawberry fruit in response to ABA or nordihydroguaiaretic acid (NDGA; an ABA biosynthesis blocker) treatment during ripening and assessed the expression changes of genes involved in the metabolism of pigments, ascorbic acid (AsA) and folic acid in the receptacles. The transcriptome analysis identified a lot of genes differentially expressed in response to ABA or NDGA treatment. In particular, genes in the anthocyanin biosynthesis pathway were actively regulated by ABA, with the exception of the gene encoding cinnamate 4-hydroxylase. Chlorophyll degradation was accelerated by ABA mainly owing to the higher expression of gene encoding pheide a oxygenase. The decrease of β-carotene content was accelerated by ABA treatment and delayed by NDGA. A high negative correlation rate was found between ABA and β-carotene content, indicating the importance of the requirement for ABA synthesis during fruit ripening. In addition, evaluation on the folate biosynthetic pathway indicate that ABA might have minor function in this nutrient’s biosynthesis process, however, it might be involved in its homeostasis. Surprisingly, though AsA content accumulated during fruit ripening, expressions of genes involved in its biosynthesis in the receptacles were significantly lower in ABA-treated fruits. This transcriptome analysis expands our understanding of ABA’s role in phytochemical metabolism during strawberry fruit ripening and the regulatory mechanisms of ABA on these pathways were discussed. Our study provides a wealth of genetic information in the metabolism pathways and may be helpful for molecular manipulation in the future.

Antioxidant activity and protective effect of banana peel against oxidative hemolysis of human erythrocyte at different stages of ripening

Phytochemicals such as polyphenols and carotenoids are gaining importance because of their contribution to human health and their multiple biological effects such as antioxidant, antimutagenic, anticarcinogenic, and cytoprotective activities and their therapeutic properties. Banana peel is a major by-product in pulp industry and it contains various bioactive compounds like polyphenols, carotenoids, and others. In the present study, effect of ripening, solvent polarity on the content of bioactive compounds of crude banana peel and the protective effect of peel extracts of unripe, ripe, and leaky ripe banana fruit on hydrogen peroxide-induced hemolysis and their antioxidant capacity were investigated. Banana (Musa paradisica) peel at different stages of ripening (unripe, ripe, leaky ripe) were treated with 70% acetone, which were partitioned in order of polarity with water, ethyl acetate, chloroform (CHCl₃), and hexane sequentially. The antioxidant activity of the samples was evaluated by the red cell hemolysis assay, free radical scavenging (1,1-diphenyl-2-picrylhydrazyl free radical elimination) and superoxide dismutase activities. The Folin-Ciocalteu's reagent assay was used to estimate the phenolic content of extracts. The findings of this investigation suggest that the unripe banana peel sample had higher antioxidant potency than ripe and leaky ripe. Further on fractionation, ethyl acetate and water soluble fractions of unripe peel displayed high antioxidant activity than CHCl₃ and hexane fraction, respectively. A positive correlation between free radical scavenging capacity and the content of phenolic compound were found in unripe, ripe, and leaky ripe stages of banana peel.