Polyphenols are natural antioxidants and play a vital role in inhibiting oxidative stress induced by the body’s free radicals. Banana peels are a significant agro-industrial waste. This waste could be utilized to extract polyphenols to process various functional foods and nutraceuticals. An investigation was executed to extract polyphenols from banana peel using the sonication and maceration techniques. Three different polar solvents, methanol, ethanol and acetone, were used at four different concentrations: 25%, 50%, 75% and 100%. Yield (%), Total Polyphenolic Content (TPC), Total Flavonoid Content (TFC) and 1,1-diphenyl-2-picryl-hydrazyl (DPPH) Radical Scavenging assays were performed. The results from the current study articulate that extraction by sonication yields a higher quantity of polyphenols than the maceration technique. The study also concludes that ethanol leads to better extraction than other solvents used in this study.

The current study aimed to determine the effects of different levels of Zingiber officinale as a herbal feed additive on growth performance, carcass characteristic, serum biochemistry, total bacterial count (TBC), gut morphology, and immunological parameters of broilers. A total of 1500, day-old broiler chicks (Hubbard) were equally accredited to five treatment groups, each with six replicates (50 birds/replicate). Five experimental diets were prepared using basal diet i.e. with antibiotics positive control (PC), 3 g/kg ginger (group A), 6 g/kg ginger (group B), 9 g/kg ginger (group C) and without antibiotics negative control (NC). Group A and C showed significantly (p<0.05) higher feed intake (FI) as compared to other groups. Group C showed significantly (p<0.05) lower Total bacterial count (TBC) followed by group B as compared to NC. Carcass characteristics showed non-significant effects among different treatments. Mean villi length and width were significantly (p <0.05) higher in all ginger supplemented groups as compared to the control groups. Blood serum parameters including cholesterol, triglycerides, and low-density lipoproteins (LDL) were significantly (p<0.05) lower in groups B and C in comparison with the control groups. Whereas high-density lipoproteins (HDL) was significantly higher in group B as compared to the others. In conclusion, ginger supplementation @0.6% in the basal diet significantly improved growth performance and gut morphometry of broilers. It also showed a positive impact on cholesterol, triglycerides and gut microbes. Therefore, ginger could be a better substitute for antibiotic growth promoters.

Gallic acid is a widely recognized bioactive compound that falls under the category of secondary polyphenolic metabolites and is fairly found in mango fruit waste, specifically in mango seed kernel (MSK). This study aimed to adopt a green extraction approach to extract this valuable compound via ultrasound‐assisted extraction (UAE) without using organic solvents but only water to obtain hazard‐free extracts, and the cost of extraction can be minimal. pH (2–8), solvent ratio (20–60 mL/g), temperature (30–60°C) and time (30–60 min) of extraction were the independent variables used for extraction optimization. Single‐factor experiments to obtain working ranges for selected extraction variables were carried out. A central composite design using response surface methodology was used to determine the optimum condition to obtain the maximum yield of gallic acid from MSK. The optimized extraction conditions were 3.9 pH, 36.25 mL/g solvent ratio, and 39.4°C of extraction temperature for 21.3 min. As a result, the optimized yield was 5.76 ± 0.41 mg/g, which was comparably equal to and/or better than the other solvent extraction systems. The results showed that gallic acid could efficiently be extracted via UAE under these optimal conditions. It is safer than extraction systems involving hazardous solvents that can be feasibly used for its nutraceutical and therapeutic applications.

Different types of agro-waste provide potential substrates for the extraction of bioactive compounds. Mango waste (e.g., peels and seeds) is one such example and may serve as a source of gallic acid, a well-known bioactive compound classified as a secondary polyphenolic metabolite. Here, we explored the efficacy of ultrasound-assisted extraction (UAE) in extracting gallic acid from mango seed kernels using different solvent concentrations (0–60%), solvent-to-sample ratios (10–50 mL/g), temperatures (30–60 °C), and times (10–30 min). The maximum yield of gallic acid (6.1 ± 0.09 mg/g) was obtained when using a 19.4% solvent concentration, a 29.32 mL/g solvent-to-sample ratio, and the extraction was conducted at 38.47 °C for 21.4 min, similar to the values predicted by the model equation. As compared to the conventional extraction procedure, the extract obtained by the optimized method was found to be significantly different in total phenolic content, total flavonoid content, and radical scavenging activity. Non-significant differences were observed in antimicrobial activity. The results indicate that mango seed kernels may be a good source of phenolics, and those phenolics can be effectively obtained through an optimized UAE method. Hence, mango seed kernels may be utilized as a suitable source of extracting phenolics in nutraceutical and food applications.