Parametric optimization of microwave reflux extraction of spice oleoresin from white pepper (Piper nigrum)

Updating the status quo on the extraction of bioactive compounds in agro-products using a two-pot multivariate design. A comprehensive review

Extraction is regarded as the most crucial stage in analyzing bioactive compounds. Nonetheless, due to the intricacy of the matrix, numerous aspects must be optimized during the extraction of bioactive components. Although one variable at a time (OVAT) is mainly used, this is time-consuming and laborious. As a result, using an experimental design in the optimization process is beneficial with few experiments and low costs. This article critically reviewed two-pot multivariate techniques employed in extracting bioactive compounds in food in the last decade. First, a comparison of the parametric screening methods (factorial design, Taguchi, and Plackett-Burman design) was delved into, and its advantages and limitations in helping to select the critical extraction parameters were discussed. This was followed by a discussion of the response surface methodologies (central composite (CCD), Doehlert (DD), orthogonal array (OAD), mixture, D-optimal, and Box-Behnken designs (BBD), etc.), which are used to optimize the most critical variables in the extraction of bioactive compounds in food, providing a sequential comprehension of the linear and complex interactions and multiple responses and robustness tests. Next, the benefits, drawbacks, and possibilities of various response surface methodologies (RSM) and some of their usages were discussed, with food chemistry, analysis, and processing from the literature. Finally, extraction of food bioactive compounds using RSM was compared to artificial neural network modeling with their drawbacks discussed. We recommended that future experiments could compare these designs (BBD vs. CCD vs. DD, etc.) in the extraction of food-bioactive compounds. Besides, more research should be done comparing response surface methodologies and artificial neural networks regarding their practicality and limitations in extracting food-bioactive compounds.

Analytic Hierarchy Process, Sensitivity Analysis, and Selectivity of Alphabutol Operation in 1-Butene Production

In this study, different operating parameters which contributed to the fouling formation were identified, while taking into consideration the heat and mass and balance. The effects of three operational parameters viz: reactor temperature, reactor pressure, andcatalyst ratio, feed to and out of reactor and heat exchanger cleaning time on the optimal yield were succinctly investigated using an empirical mathematical model. The optimum per pass conversion (PPC) that maximizes yield and extends pump around loop (PAL) days in service was obtained using the analytic hierarchy process (AHP). The result obtained under the optimum operational condition shows an increased yield from 84 to 85.5% and a 1% improvement in the 1-butene selectivity. Moreover, due to the decrease in maintenance activities, production increased by 1000 tons per annum. In addition to this, the cleaning cycle of the pump around the loop was extended by 9 days and the man-hour cleaning requirement was reduced by 91 days. The operating time of the pump around the loop increased by 30 days per loop with a corresponding reduction in the cleaning time of 50 h which resulted in maximum yield. This study, therefore, presented a design from the sensitivity analysis conducted with the potential benefit of informed decision-making in the process of making a trade-off between optimizing variable cost with the cost of maintaining the Alphabutol technology.

Effect of extraction technique on chemical compositions and antioxidant activities of freeze-dried green pepper

In this study, the yield, content of piperine, and antioxidant activity of pepper oleoresin obtained with the methods of maceration, ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), and ultrasound-MAE (UMAE) were analyzed, and the microstructure of pepper residue was observed. For the yield and piperine content, the UMAE method had the best extraction capacity among the four methods. While, the oleoresin obtained with maceration had the highest total phenolic content, and the antioxidant activity of the oleoresin obtained by maceration was higher than that of the extracts acquired by UAE, MAE, and UMAE, and a high positive correlation was observed between the antioxidant activity and total phenolic content of the oleoresin obtained by these extraction methods. The ideal parameters for UMAE were an 80-mesh particle size and a 1 g/10 mL solid–liquid ratio. The kinetic parameters and models of the UMAE extraction process were also compared using first- and second-order models. The second-order kinetic equation with the lowest root mean square deviation and highest adjusted correlation coefficient proved to be more suitable for describing the extraction kinetics of pepper oleoresin. This study showed that UMAE is a fast, efficient, and cost-effective technique for the extraction of green pepper oleoresin.

Upscalability and Techno-Economic Perspectives of Nonconventional Extraction Techniques of Essential Oils

Context: Nonconventional extraction methods, such as microwave, supercritical fluid, and ultrasonic, are known to be veritable means of producing solvent-free high-quality essential oils. Nonetheless, technical requirements for the utilization of these extraction technologies are often exorbitantly expensive, thereby limiting their utilization. Evidence Acquisition: Although these emerging extraction technologies have been reported to be efficient at a laboratory scale, their techno-economic analyses are necessary for proper upscaling. Scaling up nonconventional extraction has long been regarded as a critical constraint in larger industrial applications with a relatively limited body of published literature on more specific techno-economic analyses. Results: Therefore, an essential oil extraction unit’s techno-economic feasibility should be carefully assessed before an acquisition decision can be made for industrial upscaling. This review critically examined the implications of upscaling nonconventional extraction techniques while taking into consideration their techno-economic benefits. Conclusions: This study will undoubtedly assist researchers and industrial experts make an informed decision on the suitable extraction methods while taking into account the essential oil yield, quality characteristics, energy consumption, and operating costs.

Toward a Better Understanding of Metal Nanoparticles, a Novel Strategy from Eucalyptus Plants

Nanotechnology is a promising tool that has opened the doors of improvement to the quality of human's lives through its potential in numerous technological aspects. Green chemistry of nanoscale materials (1-100 nm) is as an effective and sustainable strategy to manufacture homogeneous nanoparticles (NPs) with unique properties, thus making the synthesis of green NPs, especially metal nanoparticles (MNPs), the scientist's core theme. Researchers have tested different organisms to manufacture MNPs and the results of experiments confirmed that plants tend to be the ideal candidate amongst all entities and are suitable to synthesize a wide variety of MNPs. Natural and cultivated Eucalyptus forests are among woody plants used for landscape beautification and as forest products. The present review has been written to reflect the efficacious role of Eucalyptus in the synthesis of MNPs. To better understand this, the route of extracting MNPs from plants, in general, and Eucalyptus, in particular, are discussed. Furthermore, the crucial factors influencing the process of MNP synthesis from Eucalyptus as well as their characterization and recent applications are highlighted. Information gathered in this review is useful to build a basis for new prospective research ideas on how to exploit this woody species in the production of MNPs. Nevertheless, there is a necessity to feed the scientific field with further investigations on wider applications of Eucalyptus-derived MNPs.

Holistic approach to microwave-reflux extraction and thermo-analytical fingerprints of under-utilized Artocarpus heterophyllus seed wastes

The increase in wastes generated from jackfruit seeds has been largely under-utilized in Malaysia. Due to the high nutritional and medicinal content embedded in the cellulosic structure of jackfruit wastes, a need then arises for their physicochemical elucidations. In this study, the extraction of Artocarpus heterophyllus seed was carefully investigated using Taguchi orthogonal optimization design. Complete functional group characteristics and chemical profile of the A. heterophyllus seed extracts were obtained using different physicochemical characterization. The optimal conditions of the microwave extraction parameters were determined at 5 min of irradiation time, 450 W of power and 50 °C of temperature. Under this condition, the optimal yield of 17.34 (mg/g) % was achieved at an SNR ratio of 24.78. The mass spectrometry analysis tentatively identified a total of 90 and 148 secondary metabolites at positive and negative ESI modes, respectively. The chemical profile obtained provided a baseline reference for further investigation on the food and medicinal bioactive from Artocarpus heterophyllus seed oleoresins. The FT-infrared emission spectrum shows the presence of some specific carbohydrates and amide protein functional groups directly linked to C–O (1008 cm⁻¹) the carbonyl (C=O) groups, respectively. Moreover, the morphological characteristics of the jackfruit raw and crude extracts conspicuously revealed large-sized globules which suggest the carbohydrates and protein contents. The result of this study indicates that the use of microwave extraction technology produced high-quality extracts with lower degradation of the thermal labile constituents. This will assist in determining the suitable conditions necessary for the total recovery of medicinal and nutritional constituents and conversion of agricultural waste products into useful products.