Ş. İsmail Kırbaşlar

Composition of Turkish Lemon and Grapefruit Peel Oils

Abstract Lemon [Citrus limon (L.) Burm. f.] and grapefruit (Citrusparadisi Macf.) peel oils were obtained by cold-pressing lemon and grapefruit peels. The oils were analyzed by high-resolution gas chromatograph (HRGC) and high-resolution gas chromatography/mass spectrometer (HRGC/MS). In total, 42 and 27 components have been identified in lemon and grapefruit oils, respectively. Lemon oil showed a high content of monoterpene hydrocarbons (89.9%) with limonene (61.8%), γ-terpinene (10.6%) and β-pinene (8.1%) being the first three major components. Similarly, grape-fruit oil was characterized by its higher content of monoterpene hydrocarbons (96.4%) of which limonene (92.5%) and myrcene (2.6%) were the first two major components. Grapefruit oil contained a lower amount of sesquiterpene hydrocarbons, aldehydes, alcohols and esters than that in lemon oil.

Optimisation of ultrasound‐assisted extraction of rosehip (Rosa canina L.) with response surface methodology

BACKGROUND Ultrasound-assisted extraction of polyphenols from rosehip (Rosa canina L.) was investigated. The aim of the study was to examine the extraction parameters such as extraction time (30-90 min), temperature (30-50 °C) and solvent concentration (40-100% ethanol, v/v), and to obtain the best possible combinations of these parameters by using response surface methodology. RESULTS The experiments were performed according to the face-centred central design. Total phenolic content was expressed in gallic acid equivalent (GAE) per gram of dried matter (DM). The second-order polynomial model gave a satisfactory description of the experimental data. 47.23 mg GAE g(-1) DM was predicted at the optimum operating conditions (40% EtOH composition, 50 °C of temperature, and 81.23 min of extraction time). CONCLUSION All of the parameters (ethanol concentration, extraction time and extraction temperature) used in this research have the significant effect on the extraction efficiency of total phenolic content in rosehip extracts (P < 0.05). The solvent concentration was proved to be the most significant effective on the yields obtained by ultrasound-assisted extraction.

Liquid–Liquid Equilibria of Water + Ethanol + Dibasic Esters Mixture (Dimethyl Adipate + Dimethyl Glutarate + Dimethyl Succinate) Ternary System

ABSTRACT Liquid–liquid equilibrium data for the ternary system water + ethanol + mixture of dibasic esters (dimethyl adipate + dimethyl glutarate + dimethyl succinate) have been determined experimentally at 298.15, 308.15 and 318.15 K. Complete phase diagrams were obtained by determining solubility and tie-line data. Distribution coefficients and separation factors were evaluated for the immiscibility region.

Study on Optimum Extraction Conditions for Olive Leaf Extracts Rich in Polyphenol and Flavonoid

Ultrasound-assisted extraction (UAE) of polyphenols and flavonoids from olive leaves was investigated. The effects of temperature (27−37°C), solvent concentration (10−70% ethanol (EtOH), v/v) and time (30−60 min) were determined by both experimental and Response Surface Methodology (RSM) techniques. Free radical scavenging activity for the antioxidant capacity was tested by 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical. For total phenolic content (TPC), 43.8252 mg-GAE/g dried leaf was predicted at the optimum conditions (34.18°C, 43.61% (v/v) of EtOH, and 59.99 min). In case of total flavonoid content (TFC), 31.9920 mg-CE/g dried leaf was calculated at the optimum conditions (34.44°C, 70% (v/v) of EtOH, and 60 min).

Comparison of lemon oil composition after using different extraction methods

Kıbrıs lemon (Citrus limon (L.) Burm. f.) peel was extracted by supercritical CO2 extraction (SFE), cold pressing (CP) and hydrodistillation (HD) methods. SFE, CP and HD methods have been compared and evaluated for their effectiveness in the separation of extract from fresh lemon peels. The chemical compositions of the three different extract samples were analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). Forty-four components were fully characterized by mass spectra and linear retention indices. The lemon extracts showed a high content of limonene (71.81%, 70.36% and 72.48%) with γ-terpinene (8.72%, 8.91% and 8.88%), β-pinene (6.61%, 6.72% and 6.60%), myrcene (1.55%, 1.59% and 1.73%), sabinene (1.21%, 1.48% and 1.09%), α-pinene (0.98%, 1.27% and 0.98%) and p-cimene (0.87%, 1.23% and 0.87%) being the major monoterpene hydrocarbons in the SFE, CP and HD methods, respectively. The principal sesquiterpene hydrocarbon was β-bisabolene (1.42%, 1.41% and 1.22%) in the SFE, CP and HD extracts, respectively. Neryl acetate and geranial were the main oxygenated compounds (1.25%, 1.28% and 1.21%) and (1.13%, 0.97% and 0.99%), in the SFE, CP and HD extracts, respectively. The composition of lemon extract has been split into six classes (monoterpene hydrocarbons, sesquiterpene hydrocarbons, carbonyl compounds, alcohols, esters and oxides). It was noted that there were significant differences in the carbonyl compounds, alcohol and ester classes in the SFE, CP and HD extracts.

Volatiles in Turkish clementine (Citrus clementina Hort.) peel

The peel extract of clementine (Citrus clementina Hort. ex Tan.) grown in Turkey was obtained by cold pressed (CP) and supercritical CO2 extraction (SFE) methods. The chemical compositions of the volatile extract samples were analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). In total, sixty-nine components have been identified corresponding to the (99.8%) of the whole volatiles in both samples. CP extraction led to lower amount of oxygenated compounds (3.7%) than the SFE extraction (4.2%); among these, carbonyls were predominant (2.09–2.10%) followed by alcohols (1.32–1.60%) and esters (0.12–0.40%). The main component is limonene (88.12–89.28%) followed by myrcene (4.64–3.77%). The oxygenated compounds present at higher levels are linalool (1.02–1.24%) and decanal (0.71–0.72%).

Pulsed ultrasound-assisted extraction of natural antioxidants from mandarin (Citrus deliciosa Tenore) leaves: Experimental and modeling study

ABSTRACT Pulsed ultrasound-assisted extraction (PUAE) of flavonoids and polyphenols from mandarin (Citrus deliciosa Tenore) leaves was examined. The response surface methodology (RSM) via face-centered central composite design (FCCD) was used to investigate the effects of extraction time (15–75 min), output amplitude (30–70%), and pH (4–10) to optimize the extraction process. The total phenolic material (TPM) and the total flavonoid material (TFM) and also the consumed energy of horn were measured as responses. Additionally, calorimetric calculations were done to evaluate the ultrasound energy dissipated into the solution. The calculated quadratic models were highly significant (p < 0.0001) for all the parameters studied with high correlation coefficients (R2) of 0.9722, 0.9805, and 0.9983. The results of the present study suggest that 65 min, 68.72 min, 15.00 extraction time, 61%, 59%, and 30% of ultrasound amplitude and 4, 6.7, and 4 pH of solution should be considered as optimal extraction conditions to get the optimum TPM (37.845 mg-GAE/g-DL), TFM (10.709 mg-CE/g-DL), and energy consumption (6130.275 Joule) for PUAE of mandarin leaves, respectively.

Separation of Penicillin G from Fermentation Broth Using N,N-Dioctyloctan-1-amine Extractant in Different Diluents

The extraction of penicillin G was investigated using N,N-Dioctyloctan-1-amine (TOA) with different diluents having distinct functional groups. Nine diluents were used in the study, namely, octan-1-ol, nonan-1-ol, isoamyl alcohol, ethyl ethanoate, propyl ethanoate, methyl iso butyl ketone(MIBK), octan-2-one, octane, and decane. The measurements were performed at a temperature of 298.2 K. The experimental results of batch extractions were used to calculate distribution coefficients (KD), loading factors (Z), and extraction efficiency (E). The highest distribution coefficient (KD = 5.79) was obtained with isoamyl alcohol, and its extraction efficiency was 85.27%. Further, the highest loading factor was reached to a value of 0.130 at 0.374 mol.kg−1 amine concentration. Overloading was not observed at any amine concentration. Solvatochromic model (Linear solvation Energy Relationship (LSER)) for data which obtained from alcohols experiments gives the good results as near as same to experimental results. Suitability of data between experiments and model predictions have been tested with root main square deviation (RMSD) with 0.99.

Optimization of ultrasound-assisted extraction of phenolic compounds from grapefruit (Citrus paradisi Macf.) leaves via D-optimal design and artificial neural network design with categorical and quantitative variables: Optimization of ultrasound-assisted extraction

BACKGROUND The extraction of phenolic compounds from grapefruit leaves assisted by ultrasound-assisted extraction (UAE) was optimized using response surface methodology (RSM) by means of D-optimal experimental design and artificial neural network (ANN). For this purpose, five numerical factors were selected: ethanol concentration (0-50%), extraction time (15-60 min), extraction temperature (25-50 °C), solid:liquid ratio (50-100 g L-1 ) and calorimetric energy density of ultrasound (0.25-0.50 kW L-1 ), whereas ultrasound probe horn diameter (13 or 19 mm) was chosen as categorical factor. RESULTS The optimized experimental conditions yielded by RSM were: 10.80% for ethanol concentration; 58.52 min for extraction time; 30.37 °C for extraction temperature; 52.33 g L-1 for solid:liquid ratio; 0.457 kW L-1 for ultrasonic power density, with thick probe type. Under these conditions total phenolics content was found to be 19.04 mg gallic acid equivalents g-1 dried leaf. CONCLUSION The same dataset was used to train multilayer feed-forward networks using different approaches via MATLAB, with ANN exhibiting superior performance to RSM (differences included categorical factor in one model and higher regression coefficients), while close values were obtained for the extraction variables under study, except for ethanol concentration and extraction time.

Resin-loaded cationic hydrogel: A new sorbent for recovering of grapefruit polyphenols

ABSTRACT This paper presents a study of the recovering of polyphenols from grapefruit biowastes through extraction and batch adsorption process using novel resin-loaded cationic hydrogel. To prepare adsorbent, 2-(dimethylamino) ethyl methacrylate (DMAEMA) monomer was polymerized by free radical mechanisms in presence of resin particles and then tertiary amino groups on PDMAEMA residue were quaternized using methyl iodide. The developed adsorbent was then characterized by FTIR, SEM, XRD, and Brunauer, Emmet, and Teller analysis. The resin-loaded cationic hydrogel displayed an enhanced affinity for binding with polyphenols at pH value of 10 due to the strong electrostatic attraction between positively charged adsorbent surface and solute molecules. The adsorption capacity of 60 (mg-naringin-g−1-adsorbent) was obtained when the other experimental conditions were chosen as follows: initial polyphenol concentration; 0.13 g mL−1, contact time; 30 min, temperature; 25°C. On the other hand, the adsorbent consisting solely of resin particles shown lower affinity for polyphenols. The adsorption results revealed that the resin-loaded cationic hydrogels exhibited significant improvement in the recovery of polyphenols from grapefruit peels through integrated extraction–adsorption process.