A SMART methodology for assessment of hexanal in potato crisps using electronic nose technology: sensor screening by scalar machine learning classifier method.

There is a pertinent need to develop a rapid and accurate methodology for the detection of the onset and the progression of rancidity in the most popular savory product worldwide, viz. fried potato crisps for food safety and health concerns. Rancidity in the fried crisps-one set prepared using C18:2-lean deodorized virgin coconut oil under modified deep frying conditions (140 °C, 5 min),-and another set deep fried (170 °C, 3 min) in C18:2-rich oil (simulating commercial frying conditions) was determined by 'rancidity indices' generated (using Mahalanobis distance) from the data obtained by MO-based electronic nose analysis of hexanal (in Likens-Nickerson extract of volatiles from potato crisps), the most prominent rancidity marker, using screened sensors calibrated with standard hexanal, and classified using support vector machine. This also allowed unambiguous discrimination of the two sets of potato fries. The correlation of hexanal contents with the said indices yielded robust regression models which could accurately predict rancidity status of the crisps, forgoing GC-FID analysis of rancidity marker in the same. The 'SMART' models developed would allow rapid-cum-accurate detection of the onset and progression of rancidity in fried potato crisps on an industrial scale, forgoing the need to conduct biochemical analyses. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05831-y.

Valorization of tuberose flower waste through development of therapeutic products using supercritical carbon dioxide extraction and microencapsulation technologies.

Tuberose flowers (Calcutta Single variety) valued as ornamentals globally, have short shelf-lives of 8 days at 4 ± 1 °C and are therefore discarded post senescence. Previous investigations from our laboratory have established that a combination treatment using GRAS preservatives [(sucrose (4%) and CaCl2 (0.02%)]-cum-gamma-irradiation (0.02 kGy) could extend its shelf-life to 24 days, when stored at 4 ± 1 °C with concomitant enhancement in the content of its bioactive principle, viz. methyl eugenol. Supercritical carbon dioxide (SC-CO2) extract of the tuberose flower wastes post combination treatment therefore had a higher methyl eugenol content (4.11 ± 0.05 µg/g), vis-à-vis its non-treated counterpart (2.03 ± 0.03 µg/g), and thus significantly higher antioxidant and antimicrobial potencies (MIC values of 1.83 ± 0.02 mg/ml and 1.98 ± 0.03 mg/ml against S. aureus ATCC 25923 strain and MDR strain, respectively). The microencapsulated powder of the extract (MEp) obtained by spray drying was applied for healing of epidermal wounds created on New Zealand white rabbits, post skin irritancy test (wherein no clinical sign of toxicity, redness or swelling was observed). When MEp was applied, accelerated healing occurred which commenced on day 2 and was completed by day 6 vis-à-vis that of the control powder set (without extract) which showed no signs of wound healing. Therefore, the sensorially compromised-senesced tuberose flowers, a rich source of methyl eugenol, has been successfully valorized through utilization of the same in developing a novel topical antibiotic powder against potent skin pathogens.

A Novel spice-antioxidant-based nano-vehicle as a putative green alternative of synthetic AChE inhibitor drugs.

The present treatment for Alzheimer's disease (AD) involves well known synthetic acetylcholine esterase (AChE) inhibitor drugs which besides having short duration of action also have deleterious impact on human health. Therefore, there is a need for natural plant-based biomolecule(s) with potential AChE inhibition activity (ies). The aim of the work is to design a spice-based nano-vehicle as a novel green alternative of synthetic AD drugs by nanoencapsulating a solvent-less supercritical CO2 extract of small cardamom seeds (SCE) having a synergistic consortium of five antioxidant molecules, using polyethylene glycol and emulsifiers, selected based on Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) analyses. Ellman's assay and enzyme inhibition kinetics of the antioxidant molecules as well as the extract and its nanoliposomal formulation (SCE-NL) were performed, followed by rigorous molecular docking and dynamics studies using MM-PBSA and umbrella sampling. The antioxidants exhibited significant AChE inhibition in vitro, individually with 1, 8-cineole having the least IC50 value of 65.53 ± 0.05 µg/mL. . Although SCE-NL had higher IC50 value (575.67 ± 0.5 µg/mL) vis-à-vis that of rivastigmine (67.52 ± 0.02 µg/mL), it is safer for usage being 'green'.The Lineweaver-Burk plots (Vmax ∼1.04 mM/min) revealed competitive mode(s) of inhibition of AChE with each of these antioxidants. Binding energy analyses suggested very good binding free energies and stable docking/binding complexes (between the antioxidants and AChE). This study has delivered a nanoliposomal vehicle of food antioxidants as a putative 'green' alternative of synthetic AChE inhibitor drugs.Communicated by Ramaswamy H. Sarma.

Acrylamide mitigation and 2,4-decadienal elimination in potato-crisps using L-proline accompanied by modified processing conditions.

Presence of toxic compounds such as acrylamide and 2,4-decadienal in fried products are dependent on frying temperature and time and the frying oil. Combination treatments such as aqueous pre-treatments of potato slices prior to frying; addition of L-proline to pre-treated samples; moisture reduction of samples pre-frying, replacement of refined soybean oil by deodorized-virgin-coconut oil (DVCO) as frying medium; and modification of frying time-temperature regime, were implemented to mitigate acrylamide and 2,4-decadienal in fried potato-crips, concomitantly enhancing their organoleptic quality. Based on similarity values of % acrylamide mitigation, experimental conditions were classified into four main clusters and the optimized conditions of the combination treatments obtained by central composite rotatable design were: blanching at 70 °C for 20 min; addition of 2% L-proline to pre-treated potato slices; and deep-frying in DVCO under modified frying conditions (140 °C, 5 min) successfully alleviated acrylamide (~ 99%) (confirmed by HR-MS and quantified by RP-HPLC) and 2,4-decadienal (quantified by RP-HPLC) in the fried potato-crisps, improving them sensorically. High Pearson's correlation co-efficient (r = 0.9955) was obtained between sensory scores and texture profile analyses data of the fried crisps. This mitigation strategy can be successfully extrapolated to industrial-scale frying for enhanced safety and sensory appeal of fried products. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-021-05328-6.

Fortification of a Desert Using Nanoencapsulated Supercritical Carbon Dioxide Extract of Small Cardamom Seeds: A Nutraceutical Custard with Antioxidant Synergy.

BACKGROUND: 1,8 cineole-rich supercritical CO2 extract of small cardamom seeds of Alleppey green variety exhibiting prominent antioxidant property was microencapsulated and utilized in formulating an antioxidant-rich custard. However, the antioxidant potency of the prepared custard was not appreciable. To redress the phytochemical loss during custard preparation, custard using nanoliposomes was formulated. Patents related to 1,8 cineole-rich food products have been revised thoroughly. OBJECTIVE: The objective of the current study is to examine whether nanoencapsulationmediated entrapment of antioxidants is more effective in fortifying a dessert, namely custard, vis-à-vis microencapsulated (spray dried)-mediated enhancement of antioxidative potency in the same. METHODS: Our previous investigations have established that nanoliposome of 1,8 cineole- rich supercritical CO2 extract of small cardamom seeds effectively redresses type 2 diabetes and hypercholesterolemia. In the current investigation, this pre-characterized nanoliposome which exhibited appreciable in vitro and in vivo antioxidant efficacy has been utilized at varying concentrations for fortification of a custard. The designer custard samples have been characterized for their sensory and physicochemical properties, identification of the cardamom antioxidants therein and determination of the synergistic efficacy value of the identified antioxidants. RESULTS: The custard formulated with 0.3% nanoliposomes exhibited appreciable antioxidant potency in terms of DPPH radical scavenging activity (304.58±1.09 mg/ml) and reducing power (0.020±0.001 mg BHT/g custard), conferred by its total phenolic content (0.049±0.004 mg GAE/g custard). It also had relatively more stable textural attributes vis-à-vis the control sample (formulated with the non-encapsulated native extract). GCMS analysis of the nanoliposome-fortified custard confirmed retention of the spice antioxidants, namely1,8- cineole, α-terpinyl acetate, α-terpineol and linalool and its synergistic efficacy value being greater than unity, attested to the synergistic presence of the said antioxidants therein. The newly formulated custard retained more than 4.5 times of 1,8-cineole (5.05 mg/g custard) vis-à-vis the custard sample (1.12 mg/g custard) prepared with a microencapsulated (spray-dried) formulation of the extract. Additionally, the absence of heavy metals in the formulated custard confirmed it to be safe for human consumption. CONCLUSION: This is the first study on the application of nanoliposomes of spiceuticals in the formulation of a dessert, and more emphatically on use of a 'green' supercritical CO2 extract of spice antioxidants in fortification of a dessert to achieve antioxidant synergy.

Supercritical carbon dioxide extracts of small cardamom and yellow mustard seeds have fasting hypoglycaemic effects: diabetic rat, predictive iHOMA2 models and molecular docking study.

In the present investigation, the supercritical carbon dioxide (SC-CO2) extracts of small cardamom (SC) and yellow mustard (YM) seeds have been investigated for their efficacies in combating type 2 diabetes in streptozotocin-induced Wistar albino rats. Fasting blood glucose (FBG) levels in the rats were monitored on days 8, 15 and 21. On day 15, FBG level reduced appreciably by 31·49 % in rats treated with SC seed extract and by 32·28 % in rats treated with YM seed extract, comparable to metformin (30·70 %) and BGR-34 (a commercial polyherbal drug) (31·81 %) administered rats. Either extract exhibited desirable effects on hepatic glucose-6-phosphatase, glucose-6-phosphate dehydrogenase (G6PD) and catalase activities in controlling diabetes. A molecular docking exercise was conducted to identify specific compounds in the extracts which possessed augmenting effect on G6PD. The results revealed that all the bioactive compounds in the extracts have binding affinities with the enzyme and contributed to the antidiabetic efficacies of the extracts as G6PD augmenters. The effects of the extracts on insulin sensitivity and glucose uptake were investigated using non-invasive modelling by iHOMA2 software. This in vitro approach indicated that extract administration resulted in increased both insulin sensitivity of the liver and glucose uptake in the gut. The findings of the present study attest these SC-CO2 extracts of the spices as safe alternatives of metformin and BGR-34 in combating type 2 diabetes and could be safely subjected to clinical studies. These extracts could also be employed in designing proactive food supplements in mitigating the metabolic disorder.

Ultrasonication-assisted extraction of a phytomelatonin-rich, erucic acid-lean nutraceutical supplement from mustard seeds: an antioxidant synergy in the extract by reductionism.

Phytomelatonin-rich (194.02 ± 2.45-205.80 ± 1.67 ng/g of dry mustard seeds) and erucic acid-lean (below 2%) extracts from an oilseed crop, (yellow and black mustard seeds) have been successfully obtained by ultrasonication-assisted-extraction in ethanol-water. Fourier-transform infrared spectroscopy and liquid chromatography-mass spectrum analyses have confirmed the presence of phytomelatonin along with tocopherol, ascorbic acid, limonene and linalool in the extract. Field emission scanning electron micrographs confirmed the cavitational effects of sonication on mustard seed matrices. Electron paramagnetic resonance spectroscopy established the strong antioxidant activities (72.25-75.49%) of the extracts foregoing erroneous spectrophotometric result of pan assay interference compounds. A synergistic effect value of 1.13 (greater than unity) confirmed synergistic co-existence of the antioxidants in the extract. This study interestingly revealed that an antioxidant synergy could be obtained by classical reductionism. Acute oral toxicity of the extracts were found to be greater than 5000 mg/kg body weight of rats. The extracts are perfectly safe to be utilized as antioxidative food supplements.

Is 1,8-Cineole-Rich Extract of Small Cardamom Seeds More Effective in Preventing Alzheimer's Disease than 1,8-Cineole Alone?

The present study demonstrates the efficacies of synthetic 1,8-cineole and an 1,8-cineole-rich supercritical carbon dioxide (SC-CO2) extract of small cardamom seeds in preventing oligomerization of amyloid beta peptide (Aß42) and inhibiting iron-dependent oxyradical production in vitro. The oligomerization of Aß42 was monitored by thioflavin T assay and MALDI-TOF analysis of the oligomers. The iron-dependent production of oxygen free radicals was detected by fluorometric benzoate hydroxylation assay. We observed that both pure 1,8-cineole and 1,8-cineole-rich extract of small cardamom seeds at concentrations of 50 µM and 100 µM prevented the production of reactive hydroxyl radicals from a mixture of Fe2+ and ascorbate. However, the 1,8-cineole-rich extract of small cardamom seeds prevented in vitro Aß42 oligomerization more effectively vis-à-vis the synthetic (99% pure) 1,8-cineole. Additional study on SHSY5Y cells indicated that both pure 1,8-cineole and 1,8-cineole-rich SC-CO2 extract of small cardamom seeds prevented iron-dependent cell death. Since oxidative damage, Aß42 aggregation and loss of cell viability (iron-induced) are characteristics of onset of Alzheimer's disease pathology, our results suggest a putative therapeutic role of 1,8-cineole-rich extract of small cardamom seeds over pure 1,8-cineole in preventing this neurodegenerative disease.

Consortia of bioactives in supercritical carbon dioxide extracts of mustard and small cardamom seeds lower serum cholesterol levels in rats: new leads for hypocholesterolaemic supplements from spices.

Melatonin-rich and 1,8-cineole-rich extracts have been successfully obtained from yellow mustard (YM) and small cardamom (SC) seeds, respectively, employing green technology of supercritical CO2 (SC-CO2) extraction. Chemical profiling confirmed the presence of melatonin and 1,8-cineole and co-extractants in the respective extracts. Electron paramagnetic resonance spectroscopy attested strong antioxidant activities of the extracts foregoing pan-assay interference compounds involved in spectroscopic analysis. These extracts also exhibited synergistic efficacies greater than unity confirming antioxidant synergy among the co-extracted bioactives therein. To ascertain hypocholesterolaemic efficacies, these extracts were co-administered orally with Triton X (at the pre-optimised dose of 175 mg/kg body weight (BW)) to Wistar albino rats at doses of 550, 175 and 55 mg/kg BW. Serum total cholesterol levels in the rats were monitored on days 3, 7, 15 and 21. On day 21, total cholesterol level reduced appreciably by 49·44 % in rats treated with YM seed extract and by 48·95 % in rats treated with SC seed extract, comparable with atorvastatin-administered rats (51·09 %). Either extract demonstrated inhibitory effects on hepatic 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase activity. A molecular docking exercise identified specific compounds in the extracts which possessed binding affinities comparable with therapeutically used HMG-CoA reductase inhibitors. In silico and in vivo studies concertedly concluded that the consortium of bioactive components in the extracts cannot be considered as invalid metabolic panaceas and therefore these 'green' extracts could be safely subjected to clinical studies as preventive biotherapeutics for hypercholesterolaemia. These extracts could be consumed per se as hypocholesterolaemic supplements or could be ingredients of new spice-based therapeutic foods.

Nanoliposomes of Supercritical Carbon Dioxide Extract of Small Cardamom Seeds Redresses Type 2 Diabetes and Hypercholesterolemia.

BACKGROUND & OBJECTIVES: In our previous investigation, oral administration of 1,8- cineole-rich supercritical carbon dioxide extract of small cardamom seeds in Wistar albino rats resulted in achieving normal fasting blood glucose (FBG) and serum cholesterol levels. The objective of this study was to further protect the aforesaid extract and to enhance its in vivo therapeutic efficacies in redressing type 2 diabetes and hypercholesterolemia, by encapsulating it as nanoliposomes. Patents related to nanoliposomes have been revised thoroughly. METHODS: PEGylated nanoliposomes of the aforesaid extract were formulated using soya phosphatidylcholine and Tween 80 by probe-sonication. These nanoliposomes were subjected to in vitro characterizations and were orally administered to Wistar albino rats at three different doses viz. 550, 175 and 55 mg/kg b.w. for detailed investigation of their antidiabetic and hypocholesterolemic efficacies. RESULTS: FT-IR, DSC and XRD analyses, HLB value (16), entrapment efficiency (84%) and release kinetics (obeying Higuchi model) revealed that the nanoliposomes were o/w type and were hydrophilic. They exhibited appreciable in vitro antioxidant potency (59% DPPH scavenging activity) owing to a synergistic consortium of antioxidants present therein. Oral administration of the liposomes in rats at 550 mg/kg b.w. could restore their normal FBG levels and serum lipid profiles on day 35, with desirable up-down regulations of related key enzymes. The iHOMA2 model could successfully predict the effects of nanoliposomes on insulin sensitivity and glucose uptake in rat liver and brain, respectively. CONCLUSION: Nanoliposome of 1,8-cineole rich extract of small cardamom seeds is a new biotherapeutic in redressing type 2 diabetes and hypercholesterolemia.

Development of a new equation in fuzzy logic analysis for ascertaining appropriate dose of gamma irradiation of virgin coconut oil.

Our previous investigation had established 4.2 kGy to be the appropriate dosage of gamma irradiation for removal of obnoxious rancid-acid-odor of virgin coconut oil (VCO) on the basis of sensory and electronic nose (e nose) studies. This study endeavored to revalidate the sensory data employing fuzzy logic analysis. An equation has been developed for the first time for deriving defuzzified scores, when the sum of the first and third coordinates of the triplet (a b c) of overall sensory score was greater than 100, i.e. (a + c) > 100. This study reaffirmed 4.2 kGy to be the most preferred dose for deodorization of VCO. Besides, ranking of the VCO samples were similar by either approach. •According to the fuzzy logic method, overall sensory scores were assigned to the VCO samples under investigation, these sensory scores have been represented by a triangle and a polygon when (a+c) is less and more than100, respectively.•The coordinates of the polygon were determined and a new equation has been developed for evaluating defuzzified scores, which has been validated by similarity value analysis.•This new methodology of fuzzy logic analysis can be used to rank samples rapidly and reliably, without any complexity of conventional similarity value approach.

FT-Raman spectroscopic analysis of enhanced activity of supercritical carbon dioxide treated bacterial alpha-amylase.

Our previous investigation on high pressure supercritical carbon dioxide treatment of a bacterial α-amylase had revealed enhanced activity of the same. 1H NMR analysis of the activity enhanced enzyme led the authors to hypothesize that the enhancement was possibly owing to alterations in the active site of the enzyme. In the present study, the changes in the active site of the treated enzyme was analysed by Fourier-transform Raman (FT-Raman) spectroscopy. The spectra obtained revealed shifting of bands in the active site of α-amylase indicating a nudging effect of the bonds in this region consequent to high pressure treatment. Also, shifts in bands in the OH stretching vibration of water were observed in the enzyme spectra. These variations in the spectra confirmed changes in the active site as well as in the water associated with the same that perhaps had a concerted effect on the increased activity of α-amylase.

Supercritical carbon dioxide extraction of lutein from yellow maize (Zea mays) kernels: process optimization based on lutein content, antioxidant activity, and ω-6/ω-3 fatty acid ratio.

Yellow maize kernels were subjected to supercritical carbon dioxide (SC-CO2) extraction to obtain a lutein-rich extract with potential nutraceutical properties. SC-CO2 extraction parameters (pressure and temperature) were optimized by employing a full-factorial (32) design of experiments and response surface methodology, based on yield of lutein, antioxidant activity, and ω-6/ω-3 fatty acid ratio of the extracts. A Chrastil equation was also developed for predicting the solubility of lutein in SC-CO2 under different extraction conditions. The optimized extraction condition was obtained at 500 bar, 70 °C for 90 min, at which the extract was found to possess a unique combination of the highest lutein yield (275.00 ± 3.50 µg/g of dry weight), along with a well-balanced ω-6/ω-3 fatty acid ratio (3:1). Moreover, the total phenol content and antioxidant activity were also found to be the highest at this condition. This lutein-rich extract is a promising nutraceutical or dietary supplement in the food industry.

Effect of Packaging on Shelf-life and Lutein Content of Marigold (Tagetes erecta L.) Flowers.

BACKGROUND: African marigold (Tagetes erecta L.) flowers are highly valued for their ornamental appeal as well as medicinal properties. However, their short shelf lives cause high post-harvest loss and limit their export potential. The review of patents and research articles revealed that different types of packaging designs/materials have been successfully employed for extension of shelf lives of cut flowers. OBJECTIVE: The current work focuses on designing of different packaging configurations and selection of best configuration for preservation of marigold cut flowers. METHODS: Ten packaging configurations, composed of four different packaging materials i.e., low density polyethylene (LDPE), polyethylene terephthalate, glassine paper and cellophane paper, were designed. Each pack, consisting of 20 ± 1 g of marigold flowers along with non-packaged control set were stored at 23 ± 2°C, 80% R.H., in an environmental chamber and the flowers were evaluated for their sensory attributes, phytochemical characteristics and physicochemical parameters of senescence to determine their shelf lives. RESULTS: Flowers packed in LDPE bag showed highest shelf life of 8 days with a lead of 4 days compared to control (shelf life - 4 days). This study also established for the first time the phenomenon of carotenogenesis in marigold cut flowers with significantly (P<0.01) higher production of lutein in LDPE packaged flowers. CONCLUSION: LDPE pack was the best design among the ten package designs, in preserving lutein content of marigold flowers and extending their shelf lives. This economically viable packaging can not only boost the export potential of this ornamental flower, but also allow utilization of nutraceutical potency of lutein.

Antimicrobial Cream Formulated with Supercritical Carbon Dioxide Extract of Tuberose Flowers Arrests Growth of Staphylococcus aureus.

BACKGROUND: Antimicrobial potency of herbal extracts is well known. The review of patents and research articles revealed that several herbal extracts have been employed in the formulation of topical products such as creams, exclusive of the cream reported in the present study. 0ur previous study has established antimicrobial potency of supercritical carbon dioxide extracts of tuberose flowers, better known for its sweet fragrance. OBJECTIVE: The present work focuses on formulating a topical antimicrobial herbal cream with methyl eugenol (principal antimicrobial compound) rich - supercritical carbon dioxide extract of tuberose flowers, having good combination of phytochemical and antimicrobial potencies. METHODS: Supercritical carbon dioxide parameters such as temperature, pressure and time were optimized using full factorial experimental design to obtain methyl eugenol-rich extracts. A cream was formulated using the extract having the best combination of phytochemical and antimicrobial potencies and was assayed further for in vitro antimicrobial potency; physiochemical and sensory properties. Two commercial antimicrobial cream samples were used as reference samples in the study. RESULT: The extract obtained at 40°C, 10 MPa, 135 min at 1 L min-1 flow rate of gaseous C02 showed the best combination of phytochemical and antimicrobial potencies and was used for formulation of herbal creams. The cream formulated with 5% w/w of extract arrested growth of the common human skin pathogen Staphylococcus aureus and showed stable physiochemical properties and high sensory appeal for a year. CONCLUSION: The cream could be considered as a 'finished herbal product&' in compliance with the World Health 0rganization guidelines.

Use of eugenol-lean clove extract as a flavoring agent and natural antioxidant in mayonnaise: product characterization and storage study.

Eugenol-lean fraction (98 % lower eugenol content than eugenol-rich fraction) having appreciable phytochemical properties was selectively isolated from clove buds (Syzygium aromaticum Linn) using supercritical carbon dioxide extraction at 40 °C and pressure of 25 MPa with static and dynamic time of 120 and 30 min respectively using ground clove powder which was previously subjected to steam distillation. The extract was used as a flavor ingredient (replacing mustard in classical formulation) and also as a source of natural antioxidant in formulating a new mayonnaise product to improve its nutraceutical value and shelf-life. This product was found to be comparable to the mustard formulated sample (experimental control) organoleptically. The sample did not have typical pungency of clove and had improved physical properties such as increased color tonality with higher chroma values, lower thermal and non-thermal creaming, homogenous and compact microstructure and higher consistency index vis-à-vis the control and standard market samples, even at the end of the storage period of 6 months. Mayonnaise formulated with eugenol-lean clove extract had significantly higher antioxidant activity (IC50 = 10.85 mg/mL), phenolic content (1.89 mg gallic acid equivalent/g mayonnaise) and reducing power (11.29 mg BHT equivalent/g mayonnaise) than mustard-formulated mayonnaise and the market sample. While, the antioxidant activity and phytochemical properties tend to decrease after 30 days for the reference market sample and after 90 days for the experimental control sample, the mayonnaise formulated with eugenol-lean clove extract was found to be stable beyond 6 months.

Enzyme-assisted supercritical carbon dioxide extraction of black pepper oleoresin for enhanced yield of piperine-rich extract.

Black pepper (Piper nigrum L.), the King of Spices is the most popular spice globally and its active ingredient, piperine, is reportedly known for its therapeutic potency. In this work, enzyme-assisted supercritical carbon dioxide (SC-CO2) extraction of black pepper oleoresin was investigated using α-amylase (from Bacillus licheniformis) for enhanced yield of piperine-rich extract possessing good combination of phytochemical properties. Optimization of the extraction parameters (without enzyme), mainly temperature and pressure, was conducted in both batch and continuous modes and the optimized conditions that provided the maximum yield of piperine was in the batch mode, with a sample size of 20 g of black pepper powder (particle diameter 0.42 ± 0.02 mm) at 60 °C and 300 bar at 2 L/min of CO2 flow. Studies on activity of α-amylase were conducted under these optimized conditions in both batch and continuous modes, with varying amounts of lyophilized enzyme (2 mg, 5 mg and 10 mg) and time of exposure of the enzyme to SC-CO2 (2.25 h and 4.25 h). The specific activity of the enzyme increased by 2.13 times when treated in the continuous mode than in the batch mode (1.25 times increase). The structural changes of the treated enzymes were studied by (1)H NMR analyses. In case of α-amylase assisted extractions of black pepper, both batch and continuous modes significantly increased the yields and phytochemical properties of piperine-rich extracts; with higher increase in batch mode than in continuous.

Facile and rapid thermo-regulated biomineralization of gold by pullulan and study of its thermodynamic parameters.

A novel method for the production of gold nanoparticles (AuNPs) using pullulan as reducing and stabilizing agent has been developed. Quasi-spherical shaped AuNPs in the range of 50-100 nm were produced at three different temperature regimes 80°C, 90°C and 100°C as characterized using UV-vis spectrophotometer, TEM and DLS. Study of reaction kinetics and thermodynamic parameters indicated that the reaction between pullulan and chloroauric acid for AuNPs formation followed first order reaction kinetics and higher temperature was favorable for the synthesis of smaller sized AuNPs. FT-IR data analyses, provided an insight towards the mechanism of gold nanoparticle formation which suggested that, the free CH2OH groups of pullulan molecule were oxidized to carboxylate ions resulted in formation of AuNPs whereas the basic skeletal structure of pullulan remained unaltered. This study may open up new avenues for synthesis of tailor made biogenic AuNPs with possible application in biomedical field.

Physicochemical and Phytochemical Analyses of Copra and Oil of Cocos nucifera L. (West Coast Tall Variety).

Coconut copra from West coast tall variety, cultivated in Kerala, India, was subjected to aqueous and solvent extractions (using n-hexane). Additionally, oil was extracted from the copra in Soxhlet assembly using petroleum ether (b.p. 60-80°C). Physicochemical and phytochemical analyses were conducted for the extracts and the oil, with commercial coconut oil as the experimental control. The physicochemical analyses showed that the aqueous extract of copra was milky-white in color with a sweet odor, while the solvent extract was pale yellow and odorless. The commercial oil had 0.08 ± 0.02% oleic acid and a TOTOX value of 7.73 ± 0.78, lower than the Soxhlet extracted oil. Among all the extracts and oils, best phytochemical properties, antioxidant activity (DPPH activity, IC50 value 0.04 ± 0.01 mg/mL), total phenol (0.96 ± 0.04 mg gallic acid eq./g dry copra), reducing power (40.49 ± 1.84 mg BHT eq./g dry copra), and anti-inflammatory activity (NO activity, IC50 value 0.77 ± 0.06 mg/mL) were obtained in the commercial coconut oil, followed by the Soxhlet extracted oil, aqueous extract, and solvent extract. Fatty acid composition analyses showed mainly medium chain fatty acids in the copra oil with lauric acid as the predominant fatty acid (51.88% and 44.84% in Soxhlet extracted and commercial oils, resp.).

Spray Dried Extract of Phormidium valderianum as a Promising Source of Natural Antioxidant.

Microencapsulation of antioxidant-rich fraction obtained by supercritical carbon dioxide extraction (at 50°C, 500 bar with extraction time of 90 min, and flow rate of CO2 at 2 L/min) of lyophilized biomass of Phormidium valderianum was carried out in a spray dryer using maltodextrin and gum arabic. Microencapsulation conditions that provided the best combination of phytochemical properties such as antioxidant activity, phenolic content, and reducing power with reasonable powder yield were an inlet temperature of 130°C and wall material composition as maltodextrin: gum arabic = 70 : 30. Toxicological study reported that the Anatoxin-a content of this encapsulated powder was below the limit of detection of HPLC. Storage study established that encapsulation of this antioxidant-rich algal extract resulted in eight times enhancement of half-life (T 1/2) values. The release profile of microencapsulated antioxidant-rich fraction from the encapsulated powder was found to follow first order anomalous transport kinetics. Therefore, this microencapsulated algal extract with minimum toxicity is a source of natural antioxidant and could have promising use as novel dietary supplement.