Highest Extraction Yield Research Articles

Alkaline-extracted thinned young apple polyphenols as an effective scavenger against nitrite in pickles: A comparative study with ethanol-extracted polyphenols

Pickles are popular fermented vegetable products worldwide. However, nitrite residue in pickles has caused a major safety concern. In this study, we adopted 80% ethanol solution (v/v) and 4N NaOH solution as solvents to extract polyphenols from thinned young apples, and the resulting polyphenols were designated EEP (ethanol-extracted polyphenols) and AEP (alkaline-extracted polyphenols), respectively. The results showed that AEP had a higher extraction yield than EEP, and the main individual phenolic components in AEP and EEP were different. Additionally, the DPPH scavenging capacity (1,1-diphenyl-2-picrylhydrazyl free radical) of AEP was slightly higher than that of EEP, indicating that the antioxidant activity of AEP was better than that of EEP. Further experiments suggested that both AEP and EEP exhibited good nitrite-scavenging capacity under simulated acidic conditions (pH ~3.8, close to the pH of real pickle products), with AEP showing a more pronounced effect. Moreover, in a real pickle system, the nitrite-scavenging capacity of AEP was also better than that of EEP, possibly because AEP contained a higher caffeic acid content, which was proven more effective in reacting with nitrite than chlorogenic acid (the main individual polyphenol in EEP). In addition, the EEP and AEP addition did not significantly affect the original flavor and taste of the pickle, which highlights the potential application of thinned apple polyphenols in pickle production.

Development of a new scale-up equation to obtain Tucumã-of-Pará (Astrocaryum vulgare Mart.) oil rich in carotenoids using supercritical CO2 as solvent

With the growing worldwide demand for products and wealth generation, arises the need to invest in new sustainable process and engineering practices for scale-up. Thus, the aims of this work was to obtain Tucumã-of-Pará oil rich in carotenoids using supercritical CO2 and apply a new scale-up equation. Therefore, two isotherms and three pressures were used (40 °C, 60 °C, 150 bar, 250 bar, and 400 bar). In the optimized condition a kinetic study was conducted, followed by the application of a new equation based on Buckingham π theorem. The highest extraction yield (31.49 ± 0.04%) was obtained at 60 °C, 400 bar with high concentration of oleic acid. The highest carotenoids concentration (1351.8 ± 0.02 µg/g) was obtained at 40 °C, 400 bar. The developed process was efficient to obtain oil rich in carotenoids and the Buckingham π theorem elucidated a new scale-up equation with dimensionless properties.

High purity softwood lignin obtained by an eco-friendly organosolv process

Organosolv processes provide access to less degraded and higher purity lignins. However, these are rarely applied to softwood species with high lignin contents and complex condensed structures. We are presenting here the results of an optimized organosolv process, allowing for a high extraction yield of organosolv lignin from black spruce (Picea mariana), while preserving a good solid cellulose recovery. Optimized conditions are 70% ethanol liquor with a ratio of 1:10 (wood:liquor) and 5% FeCl3·6H2O as catalyst, treated in a Parr reactor for 90 min at 180 °C. The cellulosic pulp was then extracted with pure ethanol to recover the 2nd lignin. This 2nd lignin was darker in colour and denser than the 1st lignin obtained by precipitation from residual liquor. The other lignin properties were almost identical. The total lignin recovery averaged at 74% (with a purity of 97%), the highest result for lignin recovery from softwoods published so far.

Optimization of Pressurized Liquid Extraction and In Vitro Neuroprotective Evaluation of Ammodaucus leucotrichus. Untargeted Metabolomics Analysis by UHPLC-MS/MS.

Ammodaucus leucotrichus is a spontaneous plant endemic of the North African region. An efficient selective pressurized liquid extraction (PLE) method was optimized to concentrate neuroprotective extracts from A. leucotrichus fruits. Green solvents were tested, namely ethanol and water, within a range of temperatures between 40 to 180 °C. Total carbohydrates and total phenolics were measured in extracts, as well as in vitro antioxidant capacity (DPPH radical scavenging), anticholinesterase (AChE) and anti-inflammatory (LOX) activities. Metabolite profiling was carried out by ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight tandem mass spectrometry (UHPLC-ESI-q-TOF-MS/MS), identifying 94 compounds. Multivariate analysis was performed to correlate composition with bioactivity. A remarkable effect of the temperature using water was observed: the higher temperature, the higher extraction yield, the higher total phenolic content, as well as the higher total carbohydrates content. The water extract obtained at 180 °C, 10.34 MPa and 10 min showed meaningful anti-inflammatory (IC50LOX = 39.4 µg/mL) and neuroprotective activities (IC50AChE = 55.6 µg/mL). The Principal Components Analysis (PCA) and the cluster analysis correlated these activities with the presence of carbohydrates and phenolic compounds.

Effect of Aqueous Enzymatic Extraction of Deer Oil on Its Components and Its Protective Effect on Gastric Mucosa Injury.

In this study, deer suet fat was used as a raw material to study the effects of aqueous enzymatic extraction of deer oil on its components, followed by studies into the potential protective activity, and related molecular mechanisms of deer oil on ethanol-induced acute gastric mucosal injury in rats. The results show that aqueous enzymatic extraction of deer oil not only has a high extraction yield and has a small effect on the content of active ingredients. Deer oil can reduce total stomach injury. Without affecting the blood lipid level, it can reduce the oxidative stress, which is manifested by reducing the content of myeloperoxidase (MPO) and enhancing the activity level of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). It also enhances the expression of defense factors prostaglandin (E2), epidermal growth factor (EGF), and somatostatin (SS), it inhibits apoptosis evidenced by the enhanced of Bcl-2 and decreased expression of cleavage of caspase-3 and Bax. At the same time, it reduces inflammation, which is manifested by reducing the expression of IL-1β, interleukin 6 (IL-6), and tumor necrosis factor alpha (TNF-α) gastric tissue pro-inflammatory cytokines, and enhancing the expression of anti-inflammatory factors IL-4 and IL-10, and inhibiting the mitogen-activated protein kinase/nuclear factor kappa B (MAPK/NF-κB) signaling pathway in gastric tissue.

Design and evaluation of non-conventional extraction for bioactive compounds recovery from spent coffee (Coffea arabica L.) grounds

Spent coffee grounds are one of the most interesting waste streams of coffee industry containing antioxidants, whose extraction may represent an innovative solution for the reduction of the environmental burden of this waste, simultaneously providing high added value compounds. The aim of this work was to valorize SCG (Coffea arabica L.) using a non-conventional technique (high pressure and temperature extraction), by providing pivotal information and experimental data essential for the design of a profitable and green process. A 3-level factorial design was firstly employed to verify the combined effects of ethanol concentration in water, used as solvent, and temperature on total polyphenol yield and antiradical power of the extract. Desirability method was used to estimate the optimal conditions (ethanol 50% (v/v) as solvent at 150°C), allowing the recovery of remarkable amount of bioactive compounds (30.4±1.7mg/100mL of chlorogenic acid and 31.7±2.9mg/100mL of caffeine). Moreover, Peleg's model was successfully applied to describe extraction kinetic, showing that an extraction time of 60min is sufficient to produce extracts with high extraction yields (43±0.8mg caffeic acid equivalents/g dried biomass) and remarkable antiradical properties (734±11μg trolox equivalents/g dried biomass).

Phytochemical Screening and Antimicrobial Activity of Ziziphus mauritiana Lam. And Ziziphus mucronate Lam. Extracts

The objective of this study was to determine the phytochemical profile and antimicrobial activity of leaf and bark extracts of Ziziphus mauritiana and Ziziphus mucronata. For this purpose, an extraction by maceration using ethanol was carried out and the extracts were subjected to antibacterial activity assessment through qualitative and quantitative approaches. The qualitative tests were performed using agar well diffusion method while for quantitative tests minimal inhibitory, bactericidal and fungicidal concentration (MIC, MBC or MFC) were used determined through microdilution in microplates method. The antimicrobial mechanisms such as cell lysis and action on the proton pump of the extracts were also studied. The highest extraction yield was obtained with the Z. mauritiana leaf extract (28.8%). In addition, the highest contents of polyphenols (256.6 mg GEA/g DM) and flavonoids (165.2 mg CE/g DM) were obtained with the bark of Z. mucronata. The bark extracts of Z. mauritiana exhibited highest antibacterial activity (36.7 mm on Staphylococcus aureus) while, Z. mucronata extracts are more active on fungi, with the highest activity on Candida albicans (26.7 mm). The antimicrobial activity of the extract increases with the concentration and, regarding the MBC/MIC and MFC/MIC ratio, the extracts showed bacteriostatic activity on the different bacteria and fungi and the possible mechanism included an activity on the proton pump. The bark and leaf extracts of Z. mauritiana and Z. mucronata could be used in traditional medicine to treat infections due to these multiple pathogens.

Extraction yield, antioxidant activity and total phenolic content of Mimusops elengi L. fruit

Mimusops elengi L. fruit or known as Bakul fruit is believed to have a lot of benefit due to its flavonoid group compound that can have antioxidant effects. This study aimed to determine the effect of temperature and ratio between material and solvent in the extraction process on the antioxidant activity and content of phenolic compounds in Mimusops elengi L. fruit extract. This research used factorial completely randomized design with 2 factors : extraction temperature (45¼C, 60¼C, and 75¼C) and ratio of the material and solvent (1:4, 1:6, and 1:8) with 3 replications. The extraction yield, total phenolic contents and antioxidant activity of Mimusops elengi L. fruit extract were examined. Furthermore, the application of extraction temperature in 75¼C with ratio 1:8 material to solvent (w/v) has the highest extraction yield, total phenolic contents and antioxidant activity compared to others treatments.

Determination of a comprehensive set of drugs of abuse, metabolites and human biomarkers in wastewater using passive sampling followed by UHPLC-MS/MS analysis

Passive sampling of wastewater using polar organic chemical integrative samplers (POCIS) is an interesting and cost-effective strategy for the quantification of biomarkers of drugs of abuse consumption in epidemiological studies. Particularly when combined with sensitive analytical method as ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS), POCIS sampling allows the long-term and sensitive determination of a wide range of analytes. In this study, a comprehensive analytical method integrating POCIS sampling, selective solid-phase extraction (SPE) of POCIS extracts, and analysis by UHPLC-MS/MS was developed and successfully validated for 12 biomarkers of substance use, with potential use in wastewater-based epidemiology. Chromatographic separation was achieved in 11 min. The assay has a wide liner range, with lower limits of quantification of 5 ng g−1 of POCIS sorbent. The selective SPE procedure, combining both cation and anion exchange cartridges, resulted in low matrix effects (-19.3 to 22.8% for compounds with a deuterated analog internal standard and 33.4 to 42.5% for anhydroecgonine methyl ester) and high extraction yields (93.4 to 106.4%). The lab-made POCIS sampler with Oasis® HLB sorbent was adequately calibrated for 9 compounds (4 drugs of abuse, 4 drug metabolites, and 1 human non-drug lifestyle markers). The method was applied in a wastewater treatment plant in Brazil, with continuous monitoring for 392 days in 2020–2021. The highest calculated wastewater concentration among drugs of abuse and metabolites was found for benzoylecgonine (431.5 ± 190.6 ng L-1), followed by 11-nor-9-carboxy-Δ9-THC (58.3 ± 21.1 ng L-1). The assay described in this study can be used as an effective tool to monitor the presence of relevant drug consumption biomarkers in wastewater, a relevant epidemiologic strategy currently limited due to the sophisticated infrastructure needed for representative sampling.

Valorization of spent coffee grounds as the specialty material for dullness and aging of skin treatments

BackgroundCoffee beans contain oil with health benefits from fatty acids. The unprocessed and processed coffee beans are mostly identical in coffee oil quality and are substantively supplied for certain industries. However, the cost-effective valorization of specialty ingredients from spent coffee grounds for cosmetics is sparely presented. Linoleic acid-rich spent coffee oil, as a specialty material for skin lightening and antiaging cosmetics, is objectively to be presented.ResultsSpent coffee oils were prepared by different methods. The most cost-effective material with a high extraction yield, linoleic acid content and unsaturated/saturated fatty acid (UFA/SFA) ratio (13.21 ± 0.25, 32.09% and 0.97) was modified. The modified oil was boosted in linoleic acid (77.20% or 140.57% improvement) and the UFA/SFA ratio (33.12). The physicochemical properties of the oil were applicable for cosmetics as per its safety profiles in B16F10 melanoma and normal human skin fibroblast cells. The oil significantly better inhibited cellular melanogenesis than kojic and linoleic acids (p < 0.01), with prominent tyrosinase and TRP-2 inhibitions. The cellular antioxidant activity of the oil was comparable to those of ascorbic and linoleic acids. The collagen stimulating efficacy of the oil was significantly better than that of ascorbic but comparable to that of linoleic acid as indicated by the MMP-2 inhibitory activities (p < 0.01 and p < 0.001, respectively).ConclusionsThe oil is a specialty material for skin brightening and skin wrinkle reduction/skin elasticity improvement products. A successive circular bioeconomy of spent coffee ground waste in a more profitable cosmetic industry is indicated.Graphic abstract

Optimized extraction of polyphenols from leaves of Rosemary (Rosmarinus officinalis L.) grown in Lam Dong province, Vietnam, and evaluation of their antioxidant capacity

Abstract In the present study, the optimized solvent extraction conditions with regards to the total polyphenol content (TPC) and antioxidant capacity of rosemary leaf extract (RLE) were determined. The one-factor-at-a-time method was used to independently investigate the effect of several extraction parameters, including ethanol concentration (0–100% v/v), extraction temperature (50–80°C), extraction period (15–60 min), material–solvent ratio (1:5–1:10 g/mL), and extraction cycles (1, 2, and 3 times) on polyphenol content. Response surface methodology (RSM), in combination with a central composite design, was used to perform optimization. The following optimal conditions that gave maximal TPC were determined and experimentally verified: ethanol concentration of 65% (v/v), extraction temperature of 65°C, material–solvent ratio of 1:7.5 g/mL, extraction time of 15 min, and 2 cycles of extraction. These parameters corresponded with the TPC yield of 87.42 ± 0.25 mg gallic acid equivalent/g dried feed material (mg GAE/g DW). The optimal conditions gave a high extraction yield (337 ± 6 mg dried extract/g dried feed material) with 197.28 ± 3.11 mg GAE/g dried extract. The estimated models were strongly significant (p &lt; 0.05) for TPC values with significant regression coefficients (R 2) of 0.9979. The obtained RLE was supposed to be the top grade of natural antioxidant with the IC50 (DPPH assays) value of 9.4 ± 0.1 μg/mL, which is higher than that of the vitamin C by just three times (IC50 = 3.2 ± 0.1 μg/mL). Current results justify RLE as a potential agent in food preservation applications.

Utilization of stalk waste separated during processing of sun-dried figs (Ficus carica) as a source of pectin: Extraction and determination of molecular and functional properties

This study aimed the utilization of fig stalk waste as an alternative pectin source. For this purpose, the characteristics of extracted stalk waste pectin (SP) were compared with those of citrus pectin (CP) and pectin extracted from defected substandard whole sun-dried figs (FP). The SP had a higher extraction yield (11.7%) than FP (9.4%). The galacturonic acid content and degree of esterification of SP (32.3 and 50.1%) were higher than those of FP (19.9 and 38.8%), but lower than those of CP (79.3 and 56.2%), respectively. The SP and CP had different sugar compositions (d-glucose, l-rhamnose, d-galactose and l-arabinose) and weight average molecular weights, but similar FTIR profiles. The SP showed almost 1.9 and 1.6-fold higher Trolox equivalent antioxidant capacity (TEAC), and 2.7 and 2.0-fold higher water absorption capacity than CP and FP, respectively. SP at 3% (w/w) showed the second highest viscosity after CP and the highest emulsion stability. Gels of SP and CP at 1.75–3% range had similar firmness, but SP formed more fracturable gels than CP. Sun-dried fig stalk waste is a better source of pectin than defected substandard whole sun-dried figs. The SP could be utilized to develop functional food with alternative textural and rheological properties.

Tunisian Pistacia atlantica Desf. Extraction Process: Impact on Chemical and Nutritional Characteristics

AbstractPlant materials have been used in different fields such as therapeutics, cosmetics, and energy for ages. Several studies have investigated seeds, whether common or not, in order to ensure a better valuation of natural resources. Among these, Pistacia atlantica Desf. has been the subject of several works on its characterization and valorization. Among the current trends in sustainable development and environmental protection, valorizing natural wild plants via green chemistry has become prevalent. One of these plants, Pistacia atlantica Desf., is a tree that grows in arid and semi‐arid areas, notably in Tunisia, and produces seeds rich in oil. In this study extracting the oil from its seeds is tried by three methods (supercritical carbon dioxide (CO2), pressure, and hexane), and the efficiency of these extraction processes is compared in order to obtain the best yield and maximize its valorization in a variety of industrial fields. The obtained oil is found to be rich in polyunsaturated fatty acids, namely linoleic and oleic acids, with a similar acidic composition among all extraction methods. The tocopherol composition of the oil is determined using high performance liquid chromatography. The total polyphenol content is determined using the Folin‐Ciocalteu colorimetric analysis method. The results show that the seed oil of Pistacia atlantica Desf. extracted by supercritical CO2 gives the highest extraction yield (25%) and the lowest acidity and peroxide values with a high degree of oxidation at 232 and 270 nm. This method also gives the highest content of alpha, gamma, and delta tocopherol as well as total phenolic content compared to the other extraction methods. The composition of chlorophylls and carotenes in the seed oil of Pistacia atlantica Desf. is determined. Besides, the analysis of the sterol composition reveals that β‐sitosterol is still prevailing. Among all the tested extracts, the supercritical CO2 extract demonstrates the best antioxidant performance against the tested radicals. The oil extracted by supercritical carbon dioxide (CO2) is of a higher quality compared to that extracted by pressure and by hexane.Practical applications: The Pistacia atlantica Desf. oil exhibits interesting physicochemical and biological characteristics. The type of extraction affects the quality of the major and minor components in the seeds. However, the supercritical CO2 method produces a better oil quality with the presence of antioxidants such as tocopherols and polyphenols. In fact, it is found that the oil extracted by the three methods has an important sterolic profile with the predominance of β‐sitosterol. According to the classification of vegetable oils, unsaturated fatty acids of atlas pistachio oil can be categorized as oleo linoleic oil, which enhances its nutritional value. Having these characteristics, the use of this oil can be considered in agrifood products.

Microwave-assisted aqueous two-phase system based extraction of phenolics from pulses: Antioxidant properties, characterization and encapsulation

In the current study, a microwave-assisted aqueous two-phase system (MA-ATPS) was examined for the extraction of phenolic compounds from green lentils, chickpeas, and dry beans. The recovery of phenolic compounds by MA-ATPS was optimized by response surface methodology (RSM). A comparative study was performed by conventional ATPS (C-ATPS) and classical mono-phase extraction (C). The DPPH scavenging activity, ABTS antioxidant activity, and metal chelating activity of the extracts were determined. The highest extraction yield (6.68, 2.10, and 1.69 mg GAE/ g sample for green lentil, chickpea and dry bean, respectively) and antioxidant properties (70.98, 7.60, and 9.68 μmol TE/g for DPPH scavenging activity for green lentil, chickpea, and dry bean respectively) were observed from the extracts obtained by MA-ATPS. Furthermore, the phenolic extracts were encapsulated by freeze-drying and the structural characterization of microcapsules has been performed by Fourier Transform Infrared (FT-IR) spectrometry and Scanning Electron Microscopy (SEM). The releasing profiles of the encapsulated phenolic compounds were investigated. Additionally, the effects of extracts on oxidative stability on sunflower oil under accelerated storage conditions were assessed. The results of the present study proved that the MA-ATPS might be considered as an efficient environment-friendly method for extraction phenolic compounds from pulses as evidenced by the antioxidant activity of extracts. Moreover, the encapsulated phenolic extracts may serve as an alternative ingredient for the food industry to be used in various functional formulations potentially leading to an increase in the value of green lentil, chickpea, and dry bean and possibly their by-products.

Optimization of ultrasound‐assisted extraction of antioxidant compounds from Rumex hastatus with response surface methodology

Rumex hastatus is known for its nutritional and pharmacological properties. The present research explored ultrasound-assisted extraction (UAE) for antioxidants from it. Response surface methodology (RSM) was used with the Box–Behnken design. Hydro-ethanolic solvent ratio, amplitude, and temperature were the independent factors while % extraction yield, total phenolic content (TPC), total flavonoid content (TFC), antioxidant potential, and metal chelating activity (MCA) were the responses. The highest extraction yield was 11.58% that was obtained at 20% hydro-EtOH, 50℃ temperature, and 50 m amplitude. The optimum conditions for the highest TPC were 80% hydro-EtOH, 60℃ temperature, and 75 m amplitude, for the highest TFC were 80% hydro-EtOH, 50℃ temperature, and 50 m amplitude. For MCA, the optimum conditions were 20% hydro-EtOH solvent, 50℃ temperature, and 100 m amplitude, respectively. UAE proved to be an efficient green technique for the extraction of bioactive and antioxidant substances from R. hastatus. Practical applications The findings of this study are important for experts and industries related to vegetables and their antioxidant substances. The optimization work will be useful for the development of an efficient method for extraction of bioactive natural products from this plant for large-scale production.

Evaluation and characterisation of candidate prebiotics extracted from coconut husk by ultrasound-assisted extraction technique

Oligosaccharides are carbohydrates containing between three to ten sugar moieties. Certain oligosaccharides such as inulin and fructo-oligosaccharides are known as prebiotics that promote the growth of beneficial bacteria in the human gastrointestinal tract. This study began by comparing the efficiency of two different solvents (distilled water and 10% w/v sodium hydroxide) in extracting oligosaccharides from the coconut husk by ultrasound-assisted extraction (UAE). Following that, the coconut husk extract (CHE) extract was subjected to a series of prebiotic evaluation tests. The findings indicated that a significantly high extraction yield (40.51 ± 6.00%) could be achieved with 10% w/v NaOH treatment. The in vitro enzymatic digestion study found that there was 43.70 ± 0.15% of hydrolysis at pH 8 after five hours of incubation. For the in vitro gastric juice digestion, 29.21 ± 0.71% of hydrolysis was recorded at pH 1 after four hours of incubation. The extract was able to stimulate the growth of selected beneficial bacterial strains. FTIR and NMR analysis of the CHE revealed that the extract has a similar structure to the well-known prebiotic inulin.

Structural Characteristics of Crude Polysaccharides from 12 Selected Chinese Teas, and Their Antioxidant and Anti-Diabetic Activities.

Twelve representative edible Chinese teas (Camellia sinensis L.) from six categories (dark tea, black tea, oolong tea, white tea, yellow tea, and green tea) were selected in this study. Tea polysaccharides (TPs) were extracted with hot water, and their structural properties and biological activities, mainly antioxidant and anti-diabetic activities, were systematically evaluated. Results revealed that the extraction yields of TPs ranged from 1.81% to 6.38%, and Pu-erh tea polysaccharides had the highest extraction yield (6.38 ± 0.28%). The chemical compositions, molecular weight, and compositional monosaccharides of TPs varied among the six categories of tea. It appeared that all TPs were protein-bound acid heteropolysaccharides, and all TPs exhibited obvious antioxidant and anti-diabetic (e.g., α-glucosidase inhibitory and antiglycation) activities. Particularly, Pu-erh tea polysaccharides also contained the highest total phenolic and protein contents, and also exhibited the best antioxidant and anti-diabetic activities. Moreover, for the structural-function relationship, the heat map analysis found that total phenolic and protein contents in TPs were positively correlated with their antioxidant and anti-diabetic activities, indicating that the presence of phenolic compounds and proteins in the TPs might be the main contributors to their bioactivities. The conclusion from this study can help understand the structural-function relationship of crude tea polysaccharides.

Influence of Oat β-Glucan on the Survival and Proteolytic Activity of Lactobacillus rhamnosus GG in Milk Fermentation: Optimization by Response Surface

β-glucans come from cereals that have been located within compounds with prebiotic activity. They have presented several bioactivities that have determined their high functional value. The aim of this study was to identify the influence of oat β-glucan on the survival and proteolytic activity of Lactobacillus rhamnosus GG in a milk fermentation through an experimental design to optimize the process. For β-glucan extraction after dry milling of oats, two methods were applied: with and without enzymatic inactivation of the semolina. The highest extraction yield (45.25 g/L) was obtained with enzymatic inactivation. For the optimization of survival and proteolytic activity, a central design composed of axial points with two factors on three levels was used. Control factors were β-glucan and inoculum concentrations. According to response surface, the best survival growth rate of probiotic was observed with 4.38% of inoculum and 22.46 g/L of β-glucan, and the highest production of free amino groups was observed with 4.18% of inoculum and 22.71 g/L of β-glucan. Thus, β-glucan promotes the proteolytic activity of Lb. rhamnosus GG in milk fermentation.

Kinetic Study of Subcritical Water Extraction of Scopoletin, Alizarin, and Rutin from Morinda citrifolia.

Noni fruits (Morinda citrifolia) are a source of phenolic bioactive compounds (scopoletin, alizarin, and rutin), which have antioxidant, antimicrobial, anticancer, and anti-inflammatory activities. In this study, subcritical water was applied to determine the extraction yields and kinetics of phenolic compounds from noni fruits. The scopoletin and alizarin yields increased with the increase in temperature from 100 to 140 °C, while that of rutin increased up to 120 °C and then decreased at 140 °C. The yields of all the compounds rapidly increased from 1 to 2 mL/min and then slightly up to 3 mL/min of water flow rate. The extraction kinetics were assessed using two mathematical models. The two-site kinetic desorption model had a better fit for all experimental conditions throughout the extraction cycle and best described the extraction kinetics of phenolic compounds from noni fruits. The diffusion coefficients of scopoletin and alizarin at 140 °C and 3 mL/min were 3.7- and 16.2-fold higher than those at 100 °C and 1 mL/min, respectively. The activation energies of alizarin were 2.9- to 8.5-fold higher than those of scopoletin at various flow rates. Thus, subcritical water could be an excellent solvent with higher extraction yields and shorter extraction times using an environmentally friendly solvent.

Rapid green microwave assisted extraction of lutein from Chlorella sorokiniana (NIOT-2) – Process optimization

Chloropycean microalgae are looked up as a prospective alternate source for the production of xanthophyll carotenoid lutein. Despite, the market significance and multitude of nutraceutical applications of lutein commercial production from microalgae still remains a challenge due to the prohibitive downstream cost. This necessitates innovative less energy intensive, high lutein yielding green processes. The present work presents a comprehensive study on the rapid green microwave assisted extraction (MAE) of lutein from marine chlorophycean microalgae Chlorella sorokiniana (NIOT-2). The process parameters of microwave assisted alkali pre-treatment like exposure time (ET), alkali concentration (AC) and solid (biomass): liquid (aqueous Potassium hydroxide-KOH) ratio (S: L ratio) were optimized using single factor and response surface method (RSM) experiments. The optimized conditions for microwave assisted alkali pre-treatment (ET:1.47 min; AC: 8.16 M KOH and S:L ratio of 36.8:1 (mg/mL) augmented the lutein yield (20.69 ± 1.2 mg/g) 3.26 fold when compared to conventional extraction (6.35 ± 0.44 mg/g). Lutein extracted using optimized MAE conditions was purified and characterized. Visualization of the MAE extracted algal biomass using Scanning electron microscope confirmed the effective cell disruption. X-ray diffraction (XRD) analysis of microwave assisted alkali treated biomass (83.85%) revealed a significantly higher crystallinity index when compared to untreated control (17.28%). MAE pre-treatment can thus be propounded as a suitable process for lutein extraction from marine microalgae due to its amalgamated rapidity, homogenous heating, less energy intensiveness and high extraction yield.