Effect of hot-air drying processing on the volatile organic compounds and maillard precursors of Dictyophora Rubrovalvata based on GC-IMS, HPLC and LC-MS.

The dynamic changes in volatile organic compounds (VOCs), reducing sugars, and amino acids of Dictyophora rubrovalvata (DR) at various drying temperatures were analyzed using GC-IMS, HPLC, and LC-MS. Orthogonal partial least squares discriminant analysis (OPLS-DA) combined with VOCs indicated that drying temperature of 80 °C was optimal. Variable importance in the projection (VIP) and relative odor activity value (ROAV) were employed to identify 22 key VOCs. The findings suggested that esters played a predominant role among the VOCs. Pearson correlation analysis revealed that serine (Ser), glutamine (Gln), lysine (Lys), alanine (Ala), threonine (Thr), glutamic acid (Glu), asparagine (Asn), ribose, and glucose were closely associated with the formation of esters, aldehydes, ketones, pyrimidines, and pyrazines. In conclusion, this study laid a foundational theory for elucidating the characteristics aroma substances and their production pathways, providing a valuable reference for analysing the flavor characteristics of DR.

Transcriptomics analysis of the role of SdiA in desiccation tolerance of Cronobacter sakazakii in powdered infant formula.

The quorum-sensing receptor SdiA is vital for regulating the desiccation tolerance of C. sakazakii, yet the specific mechanism remains elusive. Herein, transcriptomics and phenotypic analysis were employed to explore the response of C. sakazakii wild type (WT) and sdiA knockout strain (ΔsdiA) under drying conditions. Following 20 days of drying in powdered infant formula (PIF), WT exhibited 4 log CFU/g higher survival rates compared to ΔsdiA. Transcriptome revealed similar expression patterns between csrA and sdiA, their interaction was confirmed both by protein-protein interaction analysis and yeast two-hybrid assays. Notably, genes associated with flagellar assembly and chemotaxis (flg, fli, che, mot regulon) showed significantly higher expression levels in WT than in ΔsdiA, indicating a reduced capacity for flagellar synthesis in ΔsdiA, which was consistent with cellular morphology observations. Similarly, genes involved in trehalose biosynthesis (ostAB, treYZS) and uptake (thuEFGK) exhibited similar expression patterns to sdiA, with higher levels of trehalose accumulation observed in WT under desiccation conditions compared to ΔsdiA. Furthermore, WT demonstrated enhanced protein and DNA synthesis capabilities under desiccation stress. Higher expression levels of genes related to oxidative phosphorylation were also noted in WT, ensuring efficient cellular ATP synthesis. This study offers valuable insights into how SdiA influences the desiccation tolerance of C. sakazakii, paving the way for targeted strategies to inhibit and control this bacterium.

Analytical and Experimental study of Liquid chromatography-mass spectrometry (LC-MS) profiling of the dehydrated Allium sativum and Allium cepa extracts; a gateway to therapeutic drug development.

Purpose: Practice of medicinal plants for the treatment of various ailments is a history for several decades. Occurrence of active compounds in these plants makes it significant in the era of modern medicine. Garlic and onion a monocotyledonous bulbous flowering plant belonging to the genus Allium has an extensive tradition for being used as anti-inflammatory, anti-cancer, anti-hyperepidemic, anti-diabetic, anti-bacterial, neuroprotective agent against various disorders. Modern day synthetic formulations have reduced efficacy and rendered with side effects that channelled the exploration for alternate source in plants for dealing with various disorders. The present study aims to explore the bioactive compounds present in Allium sativum (Garlic) and Allium cepa (Red Onion). Methods: Garlic and onion powder was soaked in Methanol, filtered, and concentrated in a vacuum in a rotary evaporator. Fractionation was carried out.LC-MS analysis of aqueous fraction was performed using a Waters Mass Q-TOF Mass Spectrometer with diode array detector. Results: LC-MS analysis revealed the occurrence of 200 compounds in garlic and 184 compounds in onion. 3.53% in garlic and 4.37% in onion were the major chemical constituents based on the number of hits. Conclusion: This study suggests that the Allium sativum and Allium cepa herbal powders being loaded with large number of active compounds would be promising alternative agents due to their richness in antioxidants.

Enhancing physicochemical properties of papaya through osmotic dehydration with various natural sweeteners.

Osmotic processes play a crucial role in developing high-quality intermediate moisture food products. This study investigates the role of osmotic dehydration focusing on using natural sweeteners to reduce health risks from refined sugar. Jaggery and honey were used for osmosis of papaya cubes, with a Box-Behnken design to determine optimal conditions: osmosis temperature (30, 40, 50 °C), osmotic solution concentration (40, 50, 60°Brix), and osmosis time (3, 4, 5 h). Simultaneous optimization of these parameters considered responses such as water loss, solid gain, weight reduction, colour change, ascorbic acid content, lycopene content, and phenolic content. The optimized conditions were identified as 49.46 °C, 40°Brix, and 5 h for jaggery osmosed samples and 39.64 °C, 60°Brix, and 4.92 h for honey osmosed samples. Drying the osmosed samples using advanced domestic solar dryer revealed superior quality (total phenolic content and lycopene content) in jaggery osmosed papaya compared to honey osmosed papaya. The study suggests that introducing a new osmotic agent, jaggery, can enhance the nutritional value of osmosed papaya cubes.

Comparison of Oven Dried and Freeze Dried Orally Disintegrating Film (ODF) Formulations Containing Memantine Hydrochloride.

Non-compliance is a serious healthcare issue. It contributes to waste of medication, deterioration of patient's quality of life and increase in healthcare cost. It is challenging to ensure Alzheimer's disease patients to comply to their medication daily. Hence, patient friendly and innovative dosage form is required to overcome the challenges. Orally disintegrating film (ODF) is proposed as solution to non-compliance. The objective of this research was to compare oven drying and freeze drying process on the physical properties of memantine hydrochloride ODF. A central composite design was used. The factors considered were concentration of Guar Gum (0.5-1.84g), concentration of wheat starch (0.5-1.84g) and concentration of PEG 400 (0.5-1.84g). A total of 20 formulations for each drying method were prepared. The ODFs produced were then characterized using uniformity of thickness tensile strength, folding endurance, disintegration time test. The optimum formulation was selected and incorporated with memantine hydrochloride. A flexible Memantine hydrochloride ODF formulation with fast disintegration time, sufficient mechanical strength and stable over a period of six months was successfully developed. The optimum formulation has 1.50 g guar gum, 1.50 g starch and 1.50 g of PEG 400. Freeze dried films are preferred as these films are more flexible and porous that lead to faster disintegration time. The findings suggest that memantine hydrochloride ODF has the potential as an alternative dosage form in treating Alzheimer's disease.

Assessment of a LPG hybrid solar dryer assisted with smart air circulation system for drying basil leaves.

The fluctuation of solar radiation throughout the day presents a significant obstacle to the widespread adoption of solar dryers for the dehydration of agricultural products, particularly those that are sensitive to high temperatures, such as basil leaf drying during the winter season. Consequently, this recent study sought to address the limitations of solar-powered dryers by implementing a hybrid drying system that harnesses both solar energy and liquid petroleum gas (LPG). Furthermore, an innovative automatic electronic unit was integrated to facilitate the circulation of air between the drying chamber and the ambient environment. Considering the solar radiation status in Egypt, an LPG hybrid solar dryer has been developed to be suitable for both sunny and cloudy weather conditions. This hybrid solar dryer (HSD) uses indirect forced convection and a controlled auxiliary heating system (LPG) to regulate both temperature and relative humidity, resulting in increased drying rates, reduced energy consumption, and the production of high-quality dried products. The HSD was tested and evaluated for drying basil leaves at three different temperatures of50, 55, and 60 °C and three air changing rates of 70, 80, and 90%, during both summer and winter sessions. The obtained results showed that drying basil at a temperature of 60 °C and an air changing rate of 90% led to a decrease in the drying time by about 35.71% and 35.56% in summer and winter, respectively, where summer drying took 135-210 min and winter drying took 145-225 min to reach equilibrium moisture content (MC). Additionally, the effective moisture diffusivity ranged from 5.25 to 9.06 × 10- 9 m2/s, where higher values of effective moisture diffusivity (EMD) were increased with increasing both drying temperatures and air change rates. Furthermore, the activation energy decreased from 16.557 to 25.182 kJ/mol to 1.945-15.366 kJ/mol for the winter and summer sessions, respectively. On the other hand, the analysis of thin-layer kinetic showed that the Modified Midilli II model has a higher coefficient of determination R2, the lowest χ2, and the lowest root mean square error (RMSE) compared to the other models of both winter and summer sessions. Finally, the LPG hybrid solar dryer can be used for drying a wide range of agricultural products, and it is more efficient for drying medicinal plants. This innovative dryer utilizes a combination of LPG and solar energy, making it efficient and environmentally friendly.

Development of Novel Honey- and Oat-Based Cocoa Beverages-A Comprehensive Analysis of the Impact of Drying Temperature and Mixture Composition on Physical, Chemical and Sensory Properties.

This research aimed to assess the influence of drying temperature (50, 60 and 70 °C), honey/oat flour ratio (60:40, 50:50 and 40:60) and cocoa contents (5, 6.25 and 7.5 g/100 g) on the physical (color, moisture content, bulk density, flowability (Hausner ratio, Carr index), dispersibility, solubility, and particle size), chemical (total dissolved solids, conductivity, pH, amount of sugar, color, total polyphenolic content, and antioxidant activity), and sensory properties (powder appearance, color, odor; and beverage appearance, color, odor, sweetness, bitterness, taste, texture) of a newly developed cocoa powder mixture in which honey was used as a sweetener and oat flour as a filler. Also, a further aim of this study was to optimize the composition of the mixture based on chemical, physical and sensory properties. Based on the optimization results, the highest total polyphenolic content and antioxidant activity were achieved at 70 °C with a honey/oat ratio of 50% and a cocoa content of 7.5 g. Drying temperature has a significant effect on powder odor and beverage odor, as well as on beverage bitterness, while the honey/oat flour ratio has a significant effect on color, with primarily values L* and a*. The cocoa contents mostly affect total polyphenolic content and antioxidant activity.

Changes in the Volatile Flavor Substances, the Non-Volatile Components, and the Antioxidant Activity of Poria cocos during Different Drying Processes.

Poria cocos (Schw.) wolf (P. cocos) is an important medicinal material with both therapeutic and edible properties. This study investigated volatile constituents, amino acids, proteins, polysaccharides, triterpenoid ingredients, and alcohol-soluble extracts on P. cocos during eight drying processes. A total of 47 volatile components were found and identified; the main volatile components of shade drying (SD) and hot-air drying at 50 °C (HD50) were esters and alcohols, while for drying in hot air at 60 °C~100 °C (△ = 10 °C) and infrared drying (ID), the main compounds were aldehydes and hydrocarbons. The amino acids in P. cocos remained the same when dried with various methods. Compared with SD samples, with the temperature increase, the content of amino acids showed a trend of first decreasing and then increasing, while the content trend of proteins was the opposite. The HD70 samples had the highest content of polysaccharide, triterpenoid ingredients, alcohol-soluble extracts, and antioxidant activity. Furthermore, volatile compounds showed a correlation between non-volatile constituents. This research provides evidence that the aroma, active components, and activity of P. cocos were affected by the drying method.

Myxococcus xanthus fruiting body morphology is important for spore recovery after exposure to environmental stress.

Environmental microorganisms have evolved a variety of strategies to survive fluctuations in environmental conditions, including the production of biofilms and differentiation into spores. Myxococcus xanthus are ubiquitous soil bacteria that produce starvation-induced multicellular fruiting bodies filled with environmentally resistant spores (a specialized biofilm). Isolated spores have been shown to be more resistant than vegetative cells to heat, ultraviolet radiation, and desiccation. The evolutionary advantage of producing spores inside fruiting bodies is not clear. Here, we examine a hypothesis that the fruiting body provides additional protection from environmental insults. We developed a high-throughput method to compare the recovery (outgrowth) of distinct cell types (vegetative cells, free spores, and spores within intact fruiting bodies) after exposure to ultraviolet radiation or desiccation. Our data indicate that haystack-shaped fruiting bodies protect spores from extended UV radiation but do not provide additional protection from desiccation. Perturbation of fruiting body morphology strongly impedes recovery from both UV exposure and desiccation. These results hint that the distinctive fruiting bodies produced by different myxobacterial species may have evolved to optimize their persistence in distinct ecological niches.IMPORTANCEEnvironmental microorganisms play an important role in the production of greenhouse gases that contribute to changing climate conditions. It is imperative to understand how changing climate conditions feedback to influence environmental microbial communities. The myxobacteria are environmentally ubiquitous social bacteria that influence the local microbial community composition. Defining how these bacteria are affected by environmental insults is a necessary component of predicting climatic feedback effects. When starved, myxobacteria produce multicellular fruiting bodies filled with spores. As spores are resistant to a variety of environmental insults, the evolutionary advantage of building a fruiting body is not clear. Using the model myxobacterium, Myxococcus xanthus, we demonstrate that the tall, haystack-shaped fruiting body morphology enables significantly more resistance to UV exposure than the free spores. In contrast, fruiting bodies are slightly detrimental to recovery from extended desiccation, an effect that is strongly exaggerated if fruiting body morphology is perturbed. These results suggest that the variety of fruiting body morphologies observed in the myxobacteria may dictate their relative resistance to changing climate conditions.

Change of bioactive properties, spectral reflectance, and color characteristics of European cranberry (Viburnum opulus L.) juice as affected by foam mat drying technique.

The European cranberry bush, known for its health benefits, can only be consumed through fermentation. This study aimed to develop a fruit leather made from European cranberry bush using quince seed gel and the foam drying method. For this purpose, quince seed gel was added to European cranberry juice to increase consistency. Then, European cranberry fruit leather was obtained by drying at 70, 80, and 90 °C air temperatures using foam mat drying technology. Spectral reflectance, color, drying kinetics, anthocyanin, ascorbic acid, and total phenolic content, antiradical activity, and macro-micronutrient concentrations of the resulting fruit pulp were investigated. The foam mat drying process at 90 °C had the greatest values of ascorbic acid (0.996 mg g- 1), anthocyanin (275.9 mg kg- 1), DPPH (47.77%), and ABTS.+ (68.76 µg TE g- 1). In addition, the highest value of total phenolic content (37.75 mg g- 1) was obtained in the foam mat drying process at 80 °C. The highest concentration of P, Na, Mg, K, Ca, and Mn in fruit leather was obtained at 70 °C, and the highest concentration of S, Cu, and Zn was obtained at 90 °C. The lowest spectral reflectance values were measured at 90 °C. In conclusion, the present study explored the fact that adding quince seed gel, extremely rich in biochemical content, significantly enhanced the bioactivity properties of European cranberry bush fruit leather.

Role of motility and nutrient availability in drying patterns of algal droplets.

Sessile drying droplets in various bio-related systems attracted attention due to the complex interactions between convective flows, droplet pinning, mechanical stress, wettability, and the emergence of unique patterns. This study focuses on the drying dynamics of Chlamydomonas reinhardtii (chlamys), a versatile model algae used in molecular biology and biotechnology. The experimental findings shed light on how motility and nutrient availability influence morphological patterns- a fusion of macroscopic fluid dynamics and microbiology. This paper further discusses the interplay of two competing stressors during drying- nutrient scarcity (quantitative analysis) and mechanical stress (qualitative analysis), where the global mechanical stress does not induce cracks. Interestingly, motile chlamys form clusters under nutrient scarcity due to metabolic stress, indicating the onset of flocculation, a common feature observed in microbial systems. Moreover, non-motile chlamys exhibit an "anomalous coffee-ring effect" in the presence of nutrients, with an inward movement observed near the droplet edge despite sufficient water in the droplet. The quantitative image processing techniques provide fundamental insights into these behaviors in classifying the patterns into four categories (motile+with nutrients, motile+without nutrients, non-motile+with nutrients, and non-motile+without nutrients) across five distinct drying stages- Droplet Deposition, Capillary Flow, Dynamic Droplet Phase, Aggregation Phase, and Dried Morphology.

Moisture sorption isotherm and thermodynamic analysis of egg powders dried by foam-mat-assisted refractance window drying.

BACKGROUND: In the designed study, the moisture sorption isotherm and thermodynamic properties of refractance-window-dried egg white powder (EWP), egg yolk powder (EYP) and whole egg powder (WEP) were determined. RESULTS: The adsorption isotherm of egg powders was classified as type II, giving a sigmoidal shape. Peleg showed the highest goodness of fitting for egg powder. The monolayer moisture content of egg powders varied between 0.02 and 0.09 g g-1. According to the thermodynamic analysis, an increase in moisture content led to a decrease in net isosteric heat of sorption (qst), and the highest decrease was observed in EWP. The qst of EWP was calculated as 18 637 kJ mol-1, while it decreased to 3104 kJ mol-1 at 0.2 g g-1 moisture content. Like qst, sorption entropy decreased from 52.07 to 7.14 J mol-1 K-1 with increasing water activity (aw) for EWP. Increasing temperature caused a decrease in spreading pressure and was higher in EWP samples. Increasing moisture content and temperature also decreased Gibbs free energy level. CONCLUSION: Moisture sorption isotherm (MSI) is used to predict the amount of bound water in a material at a specific relative humidity and temperature. To inhibit chemical and microbiological spoilage, the drying process must continue until the monolayer moisture content is reached. In this study, the monolayer moisture content of powdered eggs for safe storage was demonstrated by MSI. Additionally, by determining the thermodynamic functions of egg powder, valuable information was obtained related to predicting the energy requirement in drying processes. © 2024 Society of Chemical Industry.

Sensory cues, behavior and fur-based drying in the rat wetness response.

It never rains in standard lab-confinements; thus we have limited understanding of animal reactions to water and wetness. To address this issue, we sprayed water on different body parts of rats and measured drying and fur temperature by thermal imaging while manipulating behavior, sensory cues and fur. Spraying water on rats resulted in fur changes (hair clumping, apex formation), grooming, shaking, and scratching. Anesthesia abolished behavioral responses, interfered with fur changes, and slowed drying. Spraying water on different body parts resulted in differential behavioral drying responses. Spraying the head resulted in grooming and shaking responses; water evaporated from the head twice as fast as water sprayed on the animal's back or belly. We observed no effect of whisker removal on post-water-spraying behavior. In contrast, local anesthesia of dorsal facial skin reduced post-water-spraying behavioral responses. Shaving of head fur drastically enhanced post-water-spraying behaviors, but reduced water loss during drying; indicating that fur promotes evaporation, acting in tandem with behavior to mediate drying. Excised wet fur patches dried and cooled faster than shaved excised wet skin. Water was sucked into distal hair tips, where it evaporated. We propose the wet-fur-heat-pump-hypothesis; fur might extract heat required for drying by cooling ambient air.

Drying kinetics and thermo-environmental analysis of a PV-operated tracking indirect solar dryer for tomato slices.

The purpose of this study is to investigate how a tracking indirect solar dryer (SD) powered by photovoltaic cells affected the drying kinetics (DK) and thermo-environmental conditions of tomato slices. In this current investigation, three air speeds (1, 1.5, and 2 m/s) are used, as well as three slice thicknesses (ST) (4, 6, and 8 mm) and two SD, one of which is integrated with fixed collector motion (FCM) and another with SD tracking collector motion (TCM). The obtained results showed that the drying time (DT) isn't significantly change with increasing air speeds from 1 to 2 m/s, this may be due to many reasons such as short DT, high temperature inside drying room, and little difference between the exanimated air speeds. When the ST is changed from 4 to 8 mm and maintaining constant air speeds, the DT for FCM and TCM rose by roughly 1.667 and 1.6 times, respectively. In addition, the drying coefficient of the TCM is higher than the FCM due to higher temperature. At 1.5 m/s air speed and 8 mm ST, the maximum values of moisture diffusivity (MD) are 7.15×10-10 and 9.30×10-10 m2/s for both FCM and TCM systems, respectively. During the study of DK, nine drying models and chose the best based on higher R2 and lower χ2 and RMSE are used. The findings of the DK analysis revealed that the modified two term II model fit the experimental data of various air speeds well when TF was dried using TCM and FCM systems at varying ST. These findings are based on recorded observations. Where the models' R2 values varied from 0.98005 to 0.99942 for FCM system and varied from 0.99386 to 0.99976 for TCM system. Regarding environmental analysis, it is found that the CO2 mitigation per lifetime is ranged between 5334.9-6795.4 tons for FCM and 6305.7-6323.3 tons for TCM.

Applications of dry chain technology to maintain high seed viability in tropical climates.

Seed storage life in tropical areas is shortened by high humidity and temperature and the general inaccessibility to dehumidifying and refrigeration systems, resulting in rapid decreases in seed viability in storage as well as a high incidence of fungal and insect infestations. The dry chain, based on rapid and deep drying of seeds after harvest followed by packaging in moisture-proof containers, has been proposed as an effective method to maintain seed quality during medium-term storage in humid climates, even without refrigeration. In addition, seed drying with zeolite drying beads can be more effective and economical than sun or heated-air drying under these warm, humid conditions. In this paper, we review recent published literature regarding the dry chain, considering different crop species, storage environments and seed traits. In addition, we provide new original data on the application of dry chain methods and their implementation at larger scales in South Asia, Latin America and Pacific Island Countries. The clear conclusion is that the combination of reusable drying beads and waterproof storage containers enables the implementation of the dry chain in tropical climates, enhancing seed viability and quality in storage of many crop species. The dry chain approach can therefore significantly enhance seed security for farmers in many tropical countries. Finally, we propose actions and strategies that could guide further scaling-up implementation of this technology.

Self-association and multimer formation in AtLEA4-5, a desiccation-induced intrinsically disordered protein from plants.

During seed maturation, plants may experience severe desiccation, leading to the accumulation of late embryogenesis abundant (LEA) proteins. These intrinsically disordered proteins also accumulate in plant tissues under water deficit. Functional roles of LEA proteins have been proposed based on in vitro studies, where monomers are considered as the functional units. However, the potential formation of homo-oligomers has been little explored. In this work, we investigated the potential self-association of Arabidopsis thaliana group 4 LEA proteins (AtLEA4) using in vitro and in vivo approaches. LEA4 proteins represent a compelling case of study due to their high conservation throughout the plant kingdom. This protein family is characterized by a conserved N-terminal region, with a high alpha-helix propensity and invitro protective activity, as compared to the highly disordered and low-conserved C-terminal region. Our findings revealed that full-length AtLEA4 proteins oligomerize and that both terminal regions are sufficient for self-association in vitro. However, the ability of both amino and carboxy regions of AtLEA4-5 to self-associate invivo is significantly lower than that of the entire protein. Using high-resolution and quantitative fluorescence microscopy, we were able to disclose the unreported ability of LEA proteins to form high-order oligomers in planta. Additionally, we found that high-order complexes require the simultaneous engagement of both terminal regions, indicating that the entire protein is needed to attain such structural organization. This research provides valuable insights into the self-association of LEA proteins in plants and emphasizes the role of protein oligomer formation.

An evaluation of thermal tolerance in six tardigrade species in an active and dry state.

Tardigrades are known for their ability to survive extreme conditions. Reports indicate that tardigrade thermal tolerance is enhanced in the desiccated state; however, these reports have almost always used a single tardigrade species and drying/heating methods vary between studies. Using six different species of tardigrades we confirm that desiccation enhances thermal tolerance in tardigrades. Furthermore, we show that differences in thermal tolerance exist between tardigrade species both when hydrated and desiccated. While Viridiscus viridianus survives the highest temperatures in the hydrated state of any species tested here, under hydrated conditions, the thermal tolerance of V. viridianus is restricted to an acute transient stress. Furthermore, unlike other stresses, such as desiccation, where mild initial exposure preconditions some species to survive subsequent harsher treatment, for V. viridianus exposure to mild thermal stress in the hydrated state does not confer protection to harsher heating. Our results suggest that while tardigrades have the capacity to tolerate mild thermal stress while hydrated, survival of high temperatures in a desiccated state is a by-product of tardigrades' ability to survive desiccation.

A Comparison Analysis of Four Different Drying Treatments on the Volatile Organic Compounds of Gardenia Flowers.

The gardenia flower not only has extremely high ornamental value but also is an important source of natural food and spices, with a wide range of uses. To support the development of gardenia flower products, this study used headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) technology to compare and analyze the volatile organic compounds (VOCs) of fresh gardenia flower and those after using four different drying methods (vacuum freeze-drying (VFD), microwave drying (MD), hot-air drying (HAD), and vacuum drying (VD)). The results show that, in terms of shape, the VFD sample is almost identical to fresh gardenia flower, while the HAD, MD, and VD samples show significant changes in appearance with clear wrinkling; a total of 59 volatile organic compounds were detected in the gardenia flower, including 13 terpenes, 18 aldehydes, 4 esters, 8 ketones, 15 alcohols, and 1 sulfide. Principal component analysis (PCA), cluster analysis (CA), and partial least-squares regression analysis (PLS-DA) were performed on the obtained data, and the research found that different drying methods impact the VOCs of the gardenia flower. VFD or MD may be the most effective alternative to traditional sun-drying methods. Considering its drying efficiency and production cost, MD has the widest market prospects.

Experimental investigation of dynamic drying in single pharmaceutical granules containing acetaminophen or carbamazepine using synchrotron X-ray micro computed tomography.

Drying time, velocity, and temperature are important aspects of the drying process for pharmaceutical granules observed during tablet manufacturing. However, the drying mechanism of single granules is often limited to modelling and simulation, with the internal and physical changes difficult to quantify at an experimental level. In this study, in-situ synchrotron-based X-ray imaging techniques were used for the first time to investigate the dynamic drying of single pharmaceutical granules, quantifying internal changes occurring over the drying time. Two commonly used excipients (lactose monohydrate (LMH) and microcrystalline cellulose (MCC)) were used as pure components and binary mixtures with one of either two active pharmaceutical ingredients of differing hydrophilicity/hydrophobicity (acetaminophen (APAP) and carbamazepine (CBZ)). Water was used as a liquid binder to generate single granules of 25 % to 30 % moisture content. Results showed that for most samples, the drying time and composition significantly influences the pore volume evolution and the moisture ratio, with the velocity and temperature of the drying air possessing mixed significance on increasing the rate of pore connectivity and moisture removal depending on the sample composition. Effects of active ingredient loading resulted in minimal influence on the drying of CBZ and generated binary mixtures, with APAP and its respective mixtures' drying behaviour dominated by the material's hydrophilic nature.

Accelerated removal of solvent residuals from PLGA microparticles by alcohol vapor-assisted fluidized bed drying.

The removal of residual solvents from biodegradable poly(D,L-lactide-co-glycolide) (PLGA) microparticles by fluidized bed drying was investigated. Microparticles were prepared by the O/W solvent extraction/evaporation method and the influence of various process and formulation parameters on the secondary drying was studied. PLGA microparticles and films were characterized for residual organic solvent and water content, recrystallisation, surface morphology, drug loading and in-vitro release of the drugs dexamethasone and risperidone. While alcohol-free fluidized bed drying decreased the residual dichloromethane content only from about 7 % (w/w) to 6.4 % (w/w) (18 °C) or 3.2 % (w/w) (35 °C) within 24 h, 140 mg/L methanol vapor in purge gas facilitated almost complete removal of dichloromethane or ethyl acetate from microparticles (0-0.11 % (w/w) after 6 h). By controlling the alcohol concentration and temperature of the purge gas, the alcohol absorption and complete removal was controlled. Risperidone increased the methanol absorption enhancing the plasticization. A high initial residual water content was identified to promote aggregation and was eliminated by starting fluidized bed drying without alcohol. Alcohol vapor-assisted fluidized bed drying accelerated microparticle manufacturing without affecting the redispersibility, the drug loading and the in-vitro release of risperidone and dexamethasone.