Aliaa A. Almashad

The goal of this study is to draw attention to the vital nutrients, health advantages, and potential for encouraging the consumption of jamun fruits (Syzygium cumini L.) and making the most of their useful features to create valuable goods. In the current study, efforts have been made to evaluate the jamun fruits physicochemical characteristics and bioactive components. Moreover, ready-to-serve beverages, squash, syrup, and jam, have been prepared, and their quality has been monitored throughout the storage. Jamun fruit had an ovoid or spherical form and was a dark purple tint. The initial analysis of fruits showed 83.59 moisture, 17.56 Brix, 3.63 pH, 328.50mg cyd-3-Glu/100g anthocyanin, 219.21mg GAE/100g total phenolics, 91.33mg QE/100g total flavonoids, and 91.33 antioxidant activity. High-performance liquid chromatography examination, revealed the existence of three main anthocyanin pigments, delphinidin 3, 5-diglucoside, petunidin 3, 5-diglucoside, and malvidin 3, 5-diglucoside, which were measured at 175.80, 156.50, and 83.12mg/100g, respectively. While the main phenolic compounds present were chlorogenic, gallic, caffeic, vanillic, and catechin, with respective concentrations of 14.22, 12.18, 10.33, 6.44, and 4.13mg/100g. Total soluble solids, pH, and total sugars increased with the storage of jamun products, but acidity, total phenolic, and anthocyanin contents declined. In conclusion, jamun is a fruit that has promise for the future of producing useful goods. The various jamun fruit-based products met good standards and were sensory-acceptable.

The treatment of heavy metal-contaminated water is challenging. The use of nanomaterials from many environmental wastes is promising for removing metals and contaminants from aqueous solutions. This study is novel in using nanobiochar of water hyacinth (WH) and black tea waste (TW) as a promising approach to water decontamination owing to its unique properties that play an effective role in metal adsorption. The mono- and multi-adsorption systems of cadmium (Cd), chromium (Cr), and nickel (Ni) on biochar and nanobiochar of water hyacinths (BWH and NBWH) and black tea waste (BTW and NBTW) were investigated in this study as potential low-cost and environmentally friendly absorbents for the removal of previously mentioned heavy metals (HMs) from aqueous solutions. The WH and TW were collected from the locality, prepared, and kept until used in the experiment. Nanobiochar was prepared by grinding, characterizing, and storing in airtight containers until used. A batch experiment was designed in mono- and competitive systems to study the adsorption equilibrium behavior of HMs on biochar and nanobiochars. The Freundlich and Langmuir isotherm models were fitted to the mono- and competitive-adsorption equilibrium results. The Freundlich isotherm model provided a better fit. Furthermore, it was noticed that NBWH and NBWT efficiently removed the Cd in the mono-system by ≥99.8, especially in the smaller concentration, while NBWT and BTW removed ≥99.8 and 99.7% in the competitive system, respectively. In the mono- and competitive systems, the nanobiochars of NBTW removed more than 98.8 of Cr. The sorbents were less efficient in Ni removal compared to Cd and Cr. However, their effectiveness was very high also. The results revealed that Cd was the highest metal removed by sorbents, nanobiochars were better than biochars to remove the HMs, and the results also indicated that co-occurrence of multi-metals might fully occupy the adsorption sites on biochars and nanobiochars.