In situ poly(melamine-formaldehyde) microencapsulation of diglycidyl ether of bisphenol-A epoxy and pentaerythritol tetrakis(3-mercaptopropionate) for self-healing applications

In this study, microcapsules as potential candidates for self-healing agents were prepared by in situ polymerisation, taking place in oil-in-water emulsion. Poly(melamine-formaldehyde) is employed as shell material and diglycidyl ether of bisphenol A as polymerisable core materials and Pentaerythritol Tetrakis(3-Mercaptopropionate) as its hardener. The geometry, shell features, size distributions, core content, and the reactivity of the microcapsules were studied by scanning electron microscopy (SEM), optical microscopy (OM), Soxhlet extraction method and differential scanning calorimetry (DSC). Microcapsules with different sizes and distributions were obtained by adjusting the stirring speeds during the preparation stage. From the results, it was established that the spherical microcapsules fabricated using this technique, resulted in satisfactory size and shell structure with shell thickness of less than 2 μm. The microcapsules possess high core content at about 90 wt.% for each size range of microcapsules and it was also observed that the viscosity of the core content decreased at an elevated temperature. The results obtained in this work indicate that these microcapsules possess the characteristics that can be potentially used for self-healing applications.

Polycyclic Aromatic Hydrocarbons (PAHs) Sample Preparation and Analysis in Beverages: A Review

The monitoring of food contaminants is of interests to both food regulatory bodies and the consumers. This literature review covers polycyclic aromatic hydrocarbons (PAHs) with regard to their background, sources of exposures, and occurrence in food and environment as well as health hazards. Furthermore, analytical methods focusing on the analysis of PAHs in tea, coffee, milk, and alcoholic samples for the last 16 years are presented. Numerous experimental methods have been developed aiming to obtain better limits of detections (LODs) and percent recoveries as well as to reduce solvent consumption and laborious work. These include information such as the selected PAHs analyzed, food matrix of PAHs, methods of extraction, cleanup procedure, LOD, limits of quantitation (LOQ), and percent recovery. For the analysis of tea, coffee, milk, and alcoholic samples, a majority of the research papers focused on the 16 US Environmental Protection Agency PAHs, while PAH4, PAH8, and methylated PAHs were also of interests. Extraction methods range from the classic Soxhlet extraction and liquid–liquid extraction to newer methods such as QuEChERS, dispersive solid-phase microextraction, and magnetic solid-phase extraction. The cleanup methods involved mainly the use of column chromatography and SPE filled with either silica or Florisil adsorbents. Gas chromatography and liquid chromatography coupled with mass spectrometry or fluorescence detectors are the main analytical instruments used. A majority of the selected combined methods used are able to achieve LODs and percent recoveries in the ranges of 0.01–5 ug/kg and 70–110%, respectively, for the analysis of tea, coffee, milk, and alcoholic samples.

Comparison of Microwave-Assisted Extraction to Soxhlet Extraction of Mango Seed Kernel Oil using Ethanol and n-Hexane as Solvents

Mango seed kernel oil was extracted by Soxhlet Extraction (SE) and Microwave-Assisted Extraction (MAE) with ethanol and n-hexane as extraction solvents. To optimize the extraction condition for SE, the temperature was set to 90°C for ethanol and 80°C for n-hexane with varying solvent-to-feed ratios (S/F ratio) of 75/12, 75/10, and 60/6 mL/g. As for MAE, the same S/F ratios were considered. Extraction was done for 5, 10, and 15 minutes with microwave power levels of 120 and 240 W. It was found out that the highest yield per extraction process for SE was: 18.00±0.25 % and 9.38±2.03 % using ethanol and n-hexane, respectively; and 6.69±0.05 % and 4.68±0.06 %using ethanol and n-hexane, respectively for MAE. It was also noted that MAE, with the microwave power level of 120 W has less extraction time for about 15 minutes as compared to SE of 8 hours. Also, the best S/F ratio in this study is 60/6 for all processes. In oil quality determination, the oil extracted was examined through several tests such as FTIR, GC-MS, acid value, % FFA, iodine value, saponification value, and melting point. It was noted that oil extracted in ethanol has a better yield compared to that of n-hexane but the oil extracted using n-hexane would provide superior quality.

Production and quality assessment of mayonnaise from blends of soybean oil and african pear (Dacryodes edulis) pulp oil

Mayonnaise is an oil-in-water emulsion rich in calorie, micronutrients and fat-soluble vitamins which is produced from dominantly vegetable oil. African pear oil is a highly unsaturated oil, domestically and commercially underutilize with tonnage of postharvest losses. It presently, has little or no industrial attraction for use as commercial ingredient for food production and formulation. The aim therefore is to improve the commercial value of African pear pulp oil for use as a main ingredient in food applications, hence improving its utilization and reducing postharvest losses. Oil was extracted from African pear through Soxhlet extraction using n-hexane as the solvent and the extracted oil was blended with soybean oil in the following ratios: SO100:APO0 (Control), SO0:APO100, SO85:APO15, SO75:APO25, SO65:APO35, and SO50:APO50 for the production of mayonnaise. Some physicochemical properties of the oil blends were evaluated while proximate and sensory properties were also evaluated in the produced mayonnaise. Blending increased theiodine, acid and free fatty acid values of the oil blends and decreased significantly (p < 0.05) the peroxide value. The values ranged from 30.65 to 124.00 g iodine 100g–1, 6.85 to 2.57 mg KOH g–1, 5.03 to 1.91% and 2.62 to 3.50 meq O2 kg–1 for iodine, acid, free fatty acid and peroxide values, respectively. The proximate composition parameters of the mayonnaise samples increased significantly (p < 0.05) after blending. The values ranged from 32.65 to 35.04% for moisture, 1.12 to 1.44% for ash, 30.15 to 37.15% for fat, 1.93 to 2.31% for protein and 25.87 to 34.15% for carbohydrate. Significant improvement was recorded in the values of vitamin E, iodine and viscosity values of the mayonnaise samples after blending compared to the control with values ranging from 4.97 to 22.60 mg 100g–1 for vitamin E, 28.70 to 88.10 g iodine 100g–1 for iodine value and 24.70 to 30.13 Pa.s for viscosity. Sensory evaluation showed that the mayonnaise samples were generally acceptable by the panelists. Conclusively, blending soybean oil with African pear oil up to 50:50 could be used in the production of acceptable mayonnaise with higher fat, protein, ash, vitamin E, iodine value and viscosity, thereby reducing its postharvest losses through improved utilization.

Separation of 6-Gingerol in Zingiber Officinale Rubrum Varieties Using an Ultrasonic Assisted Extraction Method

Gingerol is a chemical compound found in red ginger, with pharmaceutical use as an analgesic drug. Generally, gingerol separation in ginger uses the Soxhlet extraction method, but this process has a weakness. It requires a long process and unsatisfactory yield. This research aims to study ultrasonic frequency effect on increasing gingerol yield in the extraction process. The variables studied were extraction times with variations of 30, 60, 90, and 120 minutes. In addition, the ultrasonic effect was also observed with variations in the ultrasonic frequency of 40 and 50 kHz compared to the solvent extraction method. This study used 70% (v/v) ethanol as a solvent and an operating temperature of 50 ºC as fixed variables.Furthermore, it used a rotary vacuum evaporator at a pressure of 350 mmHg to separate the resulting gingerol extract. Qualitative sample analysis used Thin Layer Chromatography (TLC) and scanning electron microscope (SEM) while quantitative analysis used high-performance liquid chromatography (HPLC), Waters Alliance e2695 brand with X-Terra RP18 column 100 x 4.6 mm, five μm to determine the total gingerol extract. The results showed that ultrasonic power had a significant effect on the results obtained, with the highest yield was 24.71% at the ultrasonic frequency of 50 kHz with an extraction time of 120 minutes.

The Effect of Acids on Alkaloid Yield in Pressurized Water Extraction of Narcissus Pseudonarcissus

Pressurized water (PW) extraction of galanthamine from Narcissus pseudonarcissus bulbs was performed. The obtained yield was compared with the yield from conventional acidified water extraction and methanolic Soxhlet extraction. Both PW and conventional acidified water extraction were followed by a subsequent purification step for the alkaloids. The PW extraction (70 °C, 150 bar, 45 min) yielded as much galanthamine as methanolic-Soxhlet extraction (ca. 3.50 mg/g). Meanwhile, acid-base extraction with 1% of HBr (v/v) at 65 °C for 3 h gave a lower yield (ca. 2.65 mg/g). A higher PW temperature did not significantly increase the galanthamine yield. Pressure increase is not necessary since more water-soluble compounds such as proteins and polysaccharides are co-extracted, resulting in high viscosity of the water extract solution, which hampers the filtration process. Hence, the acidity of the solution is highly important both in the case of PW extraction and acidified water extraction. Besides galanthamine, the total alkaloid profile following Narcissus alkaloids was also obtained. Lycoramine, O-methyloduline, norgalanthamine, epi-norgalanthamine, narwedine, oduline, haemanthamine, O-methyllycorenine, and a haemanthamine derivate were identified. Although a high yield was obtained from PW extraction, the further purification needs to be improved to obtain an economically feasible industrial extraction process.

In-vitro Antioxidant and Antihyperglycemic effect of Muntingia calabura L. fruit extracts

This study investigated the in-vitro antioxidant activity and antidiabetic effect of Muntingia calabura fruit extract by in-vitro α-amylase and α-glucosidase inhibitory activity. Muntingia calabura fruit was extracted with aqueous methanol by soxhlet extraction. The total phenols and total flavonoids contents were estimated and evaluated for antioxidant activities (DPPH, ABTS) and in-vitro antidiabetic activity by measuring their inhibitory activity on α-amylase and α-glucosidase levels. The findings showed that the fruit extract had high content of total phenol and exhibited moderate free radical scavenging activity. The fruit extract showed inhibitory effect on α-amylase [IC50Value =61.43 μg/mL] and α-glucosidase [IC50 Value=140.33 μg/mL] compared to standard acarbose. The fruit extract can be used as a potential source for the development of new hypoglycemic agents may be due to the presence of high phenol content.

Evaluation of Antidepressant-like Effect of Clitoria ternatea Linn.

Depressive disorder is a prevalent psychiatric disorder, which affects 21% of the world population. The presently using drugs can impose a variety of side-effects including cardiac toxicity, hypopiesia, sexual dysfunction, body weight gain, and sleep disorder. Ayurvedic medicine may be a powerful weapon given by our nature to cure disease. Considering the importance of plants as sources of drugs even today people are adopting different herbal drugs for the treatment of assorted diseases. During the last decade, there is a growing interest in the therapeutic effects of natural products on mental disorders. This study planned to assess antidepressant like activity of methanolic extract of Clitoria ternatea Linn. (fabaceae). Soxhlet extraction method was used for methanolic extraction. Antidepressant activity was studied using forced swimming test (FST) and tail suspension test (TST). Two doses 200 and 400 mg/kg of methanolic extract of flower were selected for testing. Imipramine (10 mg/kg, i.p.) were used as the reference standard drugs. Methanolic extract of Clitoria ternatea flower significantly reduced immobility time in both TST and FST. Extract increased the climbing behavior in FST, which is similar to effect observed with imipramine. The results of this study suggest that antidepressant like effect of Clitoria ternatea seems to be mediated by an increase in norepinephrine level in synapses. However further study is needed to understand mechanism of action and to isolate the active component responsible for antidepressant like activity.

Formulation of herbal cream based on Ziziphus Mauritiana leaves extract and evaluation on physicochemical properties

Plant derived substances and herbal medicines have recently attracted the great interest towards their versatile application, as medicinal plants used in traditional and modern medicine. The aim of the current study was to investigate the antioxidant activity of Ziziphus mauritiana leaves extract followed with the formulation of herbal creams based on ZM methanolic extract then evaluate the physical characteristic and stability of the creams. After the methanolic extract was obtained by using Soxhlet extraction, the extract was assessed for antioxidant activity by using stable 2,2- Diphenyl-1-picrylhydrazyl (DPPH) which showed the IC50 value of the ZM extract is 10.57 µg/ml, while IC50 value for ascorbic acid is 4.19 µg/ml. Four formulations of water in oil (w/o) emulsion based cream was formulated based on Ziziphus mauritiana leaves extract which are F1, F2, F3 and F4. Several physical properties were evaluated such as organoleptic, pH, viscosity, homogeneity, washability and emmolliency which proved that all formulations have good homogeneity, non greasy and under suitable pH and viscosity. Based on thermal stability test (45 °C ± 70 % RH, for 48 hours), it showed that F4 is not stable at high temperature compared to other formulations. Therefore, the present study indicated that the Ziziphus mauritiana leaves extract has great potential for personal care product development.

Phytochemical investigation of extracts of rhizomes of Hedychium Spicatum Sm. in A. Rees of Himachal Pradesh, India

Hedychium Spicatum is a rhizomatous perennial plant of various ethnomedicinal significance, which belongs to Zingiberaceae family.In the present study, H.Spicatum extracts were investigated for the presence of major phytochemical compounds. The dried and powdered rhizomes were extracted employing Soxhlet extraction with selective solvents of varying polarities viz water, ethanol, petroleum ether and diethyl ether. Qualitative phytochemical analysis of each of these extracts of H.Spicatum suggested the existence of flavonoids, phenolic compounds, carotenoids, alkaloids, reducing sugars (carbohydrate), proteins, steroids, saponins and oils. Greater extent of unsaturation was observed in diethyl ether and petroleum ether extracts. These extracts were also examined for their physico-chemical properties. All of the studied extracts were found to be optically active, specifically dextro rotatory. The phytochemicals present in the rhizomes suggest potential ethnomedicinal application of the species in the treatment, control and management of diseases and for new drug discovery.