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Abstract Monometallic and bimetallic Cu:Ni catalysts with different Cu:Ni molar ratios (3:1, 2:1, 1:1, 1:2, 1:3) were synthesized by wetness impregnation on activated carbon and characterized by TPR (temperature programmed reduction), XRD (X-ray diffraction) and XPS (X-ray photoelectron spectroscopy). The synthesized catalysts were evaluated in the gas phase production of diethyl carbonate from ethanol and carbon dioxide. The largest catalytic activity was obtained over the bimetallic catalyst with a Cu:Ni molar ratio of 3:1. Its improved activity was attributed to the formation of a Cu–Ni alloy on the surface of the catalyst, evidenced by XPS and in agreement with a previous assignment based on Vegard law and TPR analysis. During the reaction rate experiments, it observed the presence of a maximum of the reaction rate as a function of temperature, a tendency also reported for other carbon dioxide–alcohol reactions. It showed that the reaction rate-temperature data can be adjusted with a reversible rate equation. The initial rate as a function of reactant partial pressure data was satisfactorily adjusted using the forward power law rate equation and it was found that the reaction rate is first order in CO2 and second order in ethanol.

Recycling, in its literal sense, is the recycling of obsolete recyclable waste materials into manufacturing processes as raw materials through various recycling methods. We can say that a lot of waste is generated in environmental and industrial terms. Sunflower (Helianthus annus L.) is one of the major oil crops grown in the world for the production of edible and biodiesel oil. A large number of plant and raw material wastes, especially those used in food products, are recycled into cleaning, health, cosmetic and industrial products. In this study, the cold-pressed oil and pulp obtained from the seeds of the sunflower plant were evaluated and transformed into an added-value cosmetic product. Especially the fact that it contains other valuable compounds such as phenolic compounds, fatty acids, fibers, vitamins, minerals and polyphenols increases the popularity of the value-added product. Within the scope of our work, we produced two value-added products. These products are creams containing sunflower oil, which has nourishing, moisturizing and protective properties and the other product is a skin mask containing sunflower pulp. As our university specializes in added-value agricultural products, our product production is increasing day by day. [ABSTRACT FROM AUTHOR]

Sugarcane bagasse is a rich source for Hemicelluloses. Xylan is a major type of hemicellulose represented as glucurono- arabinoxylans (GAX) in sugarcane. In the present study, comparative analysis of different xylan extraction methods namely sodium borohydride treatment, dimethyl sulfoxide (DMSO) extraction; dilute acid treatment, sonication, hydrogen peroxide and hot water treatment methods have been carried out for extraction and purification xylan from the bagasse of sugarcane genotypes Co 86032, Co 2001 -15, SES 159, and SES 18. The results showed that alkaline extracted sugarcane bagasse yielded significantly highest xylan yield and recovery in the range of 23.85-32.35% and 72.37%-97% respectively as compared to the rest of the pretreatment methods. Moderate xylan yield (7.68-17.43%) and recovery (22.49-52.89%) was observed using hot water, sodium borohydride and hydrogen peroxide pretreatment methods with significantly highest xylan recovery of 52.89% in hydrogen peroxide pretretated bagasse. Among all the pretreatment methods studied, DMSO, dilute acid and sonication pretreated bagasse samples yielded significantly very low xylan recovery in the range of 1.21-4.89%. Fourier Transmission Infra-Red (FT-IR) spectroscopic analysis of alkali extracted xylan showed similar spectral profile of commercial Beechwood xylan and indicated the presence of hemicellulose structures. These results evidenced the simple economically feasible xylan extraction technology and provided much more scope for using sugarcane bagasse as potential xylan source to produce industrially important value added products.

• Two -NSO 3 H tethered dibutylammonium polyoxometalates of Keggin anions containing Mo and W were developed. • Extensive intramolecular H-bonding of the cation with the Keggin anion makes them insoluble in aqueous solution. • Oxidative photocatalyst activity was studied for degradation of metabromuron herbicide with H 2 O 2 as oxidant in water. • They showed excellent catalytic activity as recyclable heterogeneous oxidation catalysts. Two acidic ionic liquid-based hybrids of polyoxometalate, dibutyldisulphoammonium polyoxometalate, [DBDSA] 3 [PM 12 O 40 ], (M = Mo, W) were prepared by exchanging labile halide ion of parent ionic liquid with Keggin [PM 12 O 40 ]3− anions. The incorporation of N-SO 3 H into the ammonium cation results in intra-molecular H-bonding with POM anion, which is responsible for the preservation of heterogeneity of the catalyst throughout the reaction. Their catalytic activities were investigated for the degradation of metobromuron herbicide in aqueous medium as heterogeneous oxidative catalyst under sunlight using H 2 O 2 as oxidant. The isolated active peroxo intermediate was responsible for the reaction. A detailed mechanistic study on degradation of metobromuron into various products at different time intervals was done. The reaction for 8 h under sunlight removed greater than 70 % of TOC and also resulted in 1‑bromo-4-isocyanatobenzene as the major value-added product for the synthesis of various unsymmetrical disubstituted urea derivatives. The recyclability experiment showed excellent stability and reusability of the catalyst. [Display omitted] [ABSTRACT FROM AUTHOR]

Pickled tea is an ethnic fermented product produced using Assam tea (Camellia sinensis var. assamica) leaves. It is produced in large quantities every year and the liquid waste from its production is estimated to be up to 2500 mL per every kilogram of pickled tea production. To reduce the waste, pickled tea juice remaining from the process was developed into (1) pineapple kombucha and (2) formulated functional drinks as "value added" products. The juice used for making kombucha was collected at 15 days of pickled tea fermentation due to its high value in antioxidant activity (previous study, 2250 µmol TE per g DW). After fermenting the juice with starter culture, the properties of pineapple kombucha were assessed at 0, 1, 3, 5, 7, 9, 11 days. Results showed that the total phenolic of pineapple kombucha was reduced, while antioxidant assay (FRAP and ORAC) slightly increased. The most suitable fermentation period of pineapple kombucha was at day 3. The formulated drink was made from mixing pineapple kombucha with ginger and lemon juice at various ratios including 100:0:0, 80:10:10 and 80:15:5. The ratio 80:10:10 gave the highest TP and antioxidant activity for the functional drink. In addition, for sensory analysis, liking attribute of 80:15:5 fermented juice kombucha pineapple favor was significantly higher compared to other formulations. The study demonstrates the promising second fermentation process of by-product juice from pickled tea production for the conversion to value-added functional drink with reasonable antioxidant properties. [ABSTRACT FROM AUTHOR]

Purpose: Coffee pulp (CP), a by-product of coffee processing industry, was valorized as a functional food ingredient by exploring effects of different extractions on its phytochemicals and formulation of a novel beverage with probiotic kefir micro-organisms. Methods: Wet coffee pulp was vacuum dried, pre-treated using steam (SCP) and viscozyme (VCP) followed by aqueous extraction of its phytochemicals. Subsequently, probiotic CP beverage (PB) was formulated from SCP adding kefir cultures and evaluated for physicochemical characteristics, sensory properties and shelf life. Results: Proximate constitution of CP revealed considerable amounts of proteins (8.74 ± 1.6%), crude fiber (9.84 ± 1.8%), calcium (97.8 ± 5.2 mg/100 g) and potassium (410 ± 13.1 mg/100 g). Extraction of bio-actives using pre-treatments resulted with maximum recovery of total polyphenols (TP) and total flavonoids (TF) in SCP (14.5 ± 1.2 mg CGAE/g CP and 6.6 ± 1.2 mg CE/g CP) followed by chlorogenic acid (2.7 ± 0.5 mg/g), caffeine (2.9 ± 0.3 mg/g) and anthocyanins (0.44 ± 0.04 mg/g) corresponding to substantial antioxidant activity as compared to VCP. SCP resulted significant α- amylase (IC50 = 13.2 ± 2.2 mg/ml) and α- glucosidase (IC50 = 18.5 ± 2.1 mg/ml) inhibition demonstrating anti-diabetic potential. PB resulted with improved physicochemical properties and nutrients with a calorific value of 42.58 ± 15 kcal. Organoleptics recorded higher acceptance of PB and its shelf life studies of depicted survival of the organisms up to 30 days. Conclusion: Thus PB developed from CP with supplementation of kefir can serve as a novel healthy value added product providing sustainability to the coffee industry. [ABSTRACT FROM AUTHOR]

The natural, bio-degradable features and chemical constituents of the sugarcane bagasse (SCB) have been attracting interest as a tremendously practicable and versatile ingredient in composite materials. Eco-friendly and low value concerns have set the momentum for material science researchers to identify green substances that supply low pollutant indexes. SCB have been used as raw material for manufacturing of composite substances at multiple levels of properties and performances. This paper presents a historical point of view on the clarification of SCB and use of SCB as a value added product. This review paper also highlights the variety of method concerned in the manufacturing product from SCB. Studies on the impacts, performances and purposes of SCB in its unique condition; converted forms; dealt with appropriate chemical substances and processes, in aggregate with substances of distinct properties and manipulation of manufacturing methodologies have also been discussed from available literature. [ABSTRACT FROM AUTHOR]

Monometallic and bimetallic Cu:Ni catalysts with different Cu:Ni molar ratios (3:1, 2:1, 1:1, 1:2, 1:3) were synthesized by wetness impregnation on activated carbon and characterized by TPR (temperature programmed reduction), XRD (X-ray diffraction) and XPS (X-ray photoelectron spectroscopy). The synthesized catalysts were evaluated in the gas phase production of diethyl carbonate from ethanol and carbon dioxide. The largest catalytic activity was obtained over the bimetallic catalyst with a Cu:Ni molar ratio of 3:1. Its improved activity was attributed to the formation of a Cu-Ni alloy on the surface of the catalyst, evidenced by XPS and in agreement with a previous assignment based on Vegard law and TPR analysis. During the reaction rate experiments, it observed the presence of a maximum of the reaction rate as a function of temperature, a tendency also reported for other carbon dioxide-alcohol reactions. It showed that the reaction rate-temperature data can be adjusted with a reversible rate equation. The initial rate as a function of reactant partial pressure data was satisfactorily adjusted using the forward power law rate equation and it was found that the reaction rate is first order in CO 2 and second order in ethanol., (© 2024. The Author(s).)