Heat and microwave reflux extraction, optimization, and physicochemical characterization of oleoresins from Malaysian pepper (piper nigrum)

Emerging evidence has revealed the undeniable ability of functional plants for the treatment of many degenerative free radical-related diseases in ethnomedicine. Black and white peppers (Piper nigrum) are examples of such plants with both nutritional and medicinal properties. The free radical scavenging properties of these important commodity crops is due to the presence of various mineral elements and phenolic compounds. A need then arises to find an efficient extraction technique that gives high quality phenolic extracts at optimum condition. In this study, heat reflux extraction (HRE) and microwave reflux extraction (MRE) techniques were compared for the extraction of oleoresins from black and white pepper. The effects of these extraction methods on the extraction yield, elemental composition, phenolic content, antioxidant activities, microstructure, and functional characteristics were succinctly investigated. The performance of the two extraction techniques were thereafter evaluated at different operating levels. This was achieved firstly by examining the effects of different parameters on both the extraction yield and absorbed energy, using a single factor experiment (SFE) and Taguchi orthogonal design of experiment (TODOE). The result obtained revealed that the MRE presented a better extracts than HRE in terms of fixed oil extracted, total phenolic content, antioxidant capacity, number of phenolic compounds and mineral elements. The estimated performance index adjudged MRE to be four times and six times better than HRE in black and white pepper refluxation, respectively. Moreover, white pepper offered a better and quality natural antioxidants in terms of the quantity of fixed oil, total phenolic content, antioxidant capacity, number of phenolic compounds and mineral elements. This research therefore provided an optimized, qualitative and quantitative insight into the effects of conventional and non-conventional extraction techniques on the yield, mineral composition, phenolic content, antioxidant activities, morphological and functional characteristics of black and white pepper extracts

COMPARATIVE STUDY OF PULSED MICROWAVE AND HYDRODISTILLATION EXTRACTION OF PIPERINE OIL FROM BLACK PEPPER

Black pepper is a tropical crop with an extensive medicinal potential in alternative medicine and nutraceutical applications. The pungent bioactive piperine is responsible for this functions and its efficacy requires an efficient extraction technologies for optimal isolation. There is therefore a need to determine the best factor settings that will optimize the relative efficiency of the extraction system with minimal variability. The best factor settings was achieved using the L9 Taguchi parametric orthogonal design. The extraction parameters considered under this study were extraction time, irradiation power level, particle size and molar ratio. An optimal extraction condition was therefore achieved at 90 min extraction time, 350 W microwave power, 0.105 mm particle size and 10 mL/g molar ratio. The signal-to-noise ratio (SNR) otherwise known as response optimizer is an ideal metric in the determination of this optimum condition. The performance evaluation of reflux microwave extractor in relation to that of the hydrodistillation system placed the optimal efficiency and signal-to-noise ratio at 155.72% and 43.8469, respectively. The higher optimal efficiency obtained indicated that the microwave reflux extraction is better and more efficient than the conventional hydrodistillation techniques

Comprehensive review on some food-derived bioactive peptides with anti-hypertension therapeutic potential for angiotensin-converting enzyme (ACE) inhibition

Angiotensin-converting enzyme (ACE) inhibitory peptides have lately attracted interest since functional foods that help maintain homeostatic regulations have been developed. Rarely discussed are the intrinsic ACE-peptide interactions and their positioning, both of which help illustrate the ACE inhibitory functionalities in food-derived peptides. In this study, 173 ACE inhibitory peptides were collated using the UWM-BIOPEP database. The sequences were grouped into short, medium, and long peptides. The hydrophobicity/hydrophilicity property of peptides was analyzed using Peptide2 and the peptide binding site on ACE was predicted using PepSite2. Peptide residues interacting with ACE were denoted as reactive amino acids. Molecular docking analysis was conducted to simulate ACE-peptide binding and delineate the roles of reactive amino acids at the ultimate, penultimate, and antepenultimate positions of N—(N1, N2, and N3) and C—(C1, C2, and C3) terminals. Peptide2 analysis suggested that hydrophobic property was prominent in the peptides. The C-terminals were prominent in ACE binding for long-chained peptides through interaction with ACE hotspots. Moreover, branched-chain amino acids (BCAA) such as leucine and isoleucine were crucial at the N-terminals. The bulky side chain of BCAA forms a hydrophobic shield that protects the Zn-peptide chelate complex from water attacks. The hydrophobic fence in turn stabilizes the disrupted tetrahedral Zn-coordinate complex of ACE. This finding provided a thorough exploration of how peptide structures are related and what function they play in ACE inhibitory action. The database analysis, therefore, gave a clearer insight and comprehensive understanding into the protein-peptide interactions and provided a mechanistic explanation

Kinetic, Isotherm And Equilibrium Study Of Adsorption Of Hydrogen Sulfide From Wastewater Using Modified Eggshells

The studies of adsorption equilibrium isotherm and kinetics of hydrogen sulfide-water systems on calcite-based adsorbents prepared from eggshell are undertaken. The effects of operating variables such as contact time and initial concentration on the adsorption capacity of hydrogen sulfide are investigated. The modified eggshells are characterized by using different analytical approaches such as Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR). The batch mode adsorption process is performed at optimum removal conditions: dosage of 1 g/L, pH level of pH 6, agitation speed of 150 rpm and contact time of 14h for adsorbing hydrogen sulfide with an initial concentration of 100-500 mg/L. In the current study, the Langmuir, Freundlich, Temkin, and Dubinin models are used to predict the adsorption isotherms. Our equilibrium data for hydrogen sulfide adsorption agrees well with those of the Langmuir equation. The maximum monolayer adsorption capacity is 150.07 mg/g. Moreover, the kinetics of H2S adsorption by using the modified calcite of eggshell follows a pseudo-second-order model. From the current work, we have found that the calcite eggshell is a suitable adsorbent for H2S embeded inside the waste water. Most importantly, chicken eggshell is a waste and vastly available; hence, it could serve as a practical mean for H2S adsorption

A multi-criteria proximal bundle-based optimization approach to chick-mash feed formulation

The development of feed formulation is essentially a problem of optimization which involves selecting the best alternative, starting from a specified set of possibilities. This study is aimed at developing a generic decision supporting system for optimizing the poultry feed production through the application of multi-objective proximal bundle approach, taking into consideration the energy optimization, limiting the amino acid variation and providing a least cost of production. A non-differentiable interactive multi-objective bundle-based optimization method was used in solving this problem. This technique provided a wide range of alternatives choices for the decision maker to formulate an effective and optimum feed that will minimize the costs, achieve more balanced ration, limit the methionine variation for growth, and optimize the metabolized energy based on feed at his/her disposal. The algorithm of this method is based on the objective functions classification. According to this classification, a new (multi-objective) optimization problem was formed and solved by a Multi-objective Proximal Bundle method. The method in turn generated different alternative formulations from which the decision maker arrived at the final decisio

Characterization of agriculture wastes based activated carbon for removal of hydrogen sulfide from petroleum refinery waste water

Hydrogen sulfide (H2S) (aq) is one of the most toxic pollutants in petroleum refinery waste water. It is very harmful to human health and causes environmental and economic problems. The removal of H2S (aq) from a simulated petroleum refinery waste water using activated carbons produced from agricultural by-product such as, coconut shell (CNS), palm kernel shell (PKS), and wood sawdust (WSD) were investigated. The activated carbons obtained from the CNS, PKS, and WSD were chemically activated using KOH. The prepared ACs was characterized using SEM/EDX, FTIR, BET, and TGA. Comparative studies between all the three adsorbents for the removal of H2S (aq) from the simulated waste water were carried out. The adsorption studies revealed that modified PKS-based activated carbon (ACPKS) has shown best performance for the removal of H2S (aq). It can be concluded that ACPKS has an effective adsorbent for the removal of H2S (aq) from simulated waste water

Efficient extraction of antioxidants from Vernonia cinerea leaves: Comparing response surface methodology and artificial neural network

Despite response surface methodology (RSM) has been the most preferred statistical tool for optimizing extraction processes, artificial neural network (ANN) has been one of the most effective tools used for optimization and empirical modelling since the last two decades, most especially for non-linear equations. Thus, this study was carried out to compare the performance of RSM and ANN in optimizing the extraction yield and antioxidant capability of extract from Vernonia cinerea leaves using microwave-assisted extraction (MAE) techniques. The responses (extraction yield and antioxidant capabilities) were modelled and optimized as functions of four independent MAE parameters (irradiation time, microwave power level, ethanol concentration, and feed-to-solvent ratio) using RSM and ANN. The coefficient of determination (R2), root mean square error (RMSE) and absolute average deviation (AAD) were employed to compare the performance of both modelling tools. ANN model has a higher predictive potential compared to RSM model with higher correlation coefficients of 0.9912, 0.9928 and 0.9944 for extraction yield, DPPH and ABTS scavenging activities, respectively. Thus, ANN model could be a better alternative in data fitting for the MAE of antioxidants from Vernonia cinerea leave

Comparative analysis of polyphenolic and antioxidant constituents in dried seedlings and seedless Acacia nilotica fruits

The phenolic and antioxidant constituents in Acacia nilotica fruits have become an important source of medicinal and therapeutic benefit with powerful biological properties. This study investigated the phenolic content and antioxidant capacity of powdered Acacia fruits with seeds and without seeds. The phenolic content and antioxidant capacities in them were determined using Folin–Ciocalteu and DPPH free radical-scavenging assays. The total phenolic and antioxidants of A. nilotica with seeds were spectrophotometrically determined to be 47.61 and 6.18% greater than when the seeds were removed from the dried fruits, respectively. The LC–MS/QTOF analysis shows the presence of 282 and 214 phenolic compounds in the methanol extracts of A. nilotica with seeds and without seeds, respectively. The present study, therefore, revealed that dried A. nilotica fruits with seeds have higher total phenolic content, antioxidant capacity, and bioactive constituents, which indicated that they have more medicinal value than fruits without seeds