Purification and separation of glucomannan from porang tuber flour (Amorphophallus muelleri) using microwave assisted extraction as an innovative gelatine substituent

Effect of Soaking Treatments in Acid and Salt Solutions on Physicochemical, Structural, Thermal and Rheological Properties of Porang (Amorphophallus muelleri Blume) Flour

Research background

Porang (Amorphophallus muelleri Blume) contains a high amount of starch, glucomannan and Ca-oxalate. Soaking porang tuber in acid (citric acid) and salt (sodium chloride) solutions affects the Ca-oxalate content, functional, rheological and thermal properties of porang flour. The aim of this study is to thoroughly investigate the effect of soaking treatments in acid and salt solutions at different temperatures on the physicochemical, rheological and thermal properties, functional groups, molecular mass and morphology of porang flour.

Experimental approach

Soaking treatments in acid and salt solutions at different temperatures affect the properties of porang flour. This research investigated the effect of soaking porang slices in citric acid (5 %) and sodium chloride (8 %) solutions at different soaking temperatures (25, 55 and 85 °C for 1 h) on the properties of the resulting porang flour.

Results and conclusions

The results of this study showed that all treatments successfully reduced the Ca-oxalate mass fraction in porang flour. The acid treatments reduced the glucomannan content more than the salt treatments. Soaking in acid solutions also decreased viscosity, molecular mass and thermal stability of porang flour. When the soaking temperature was increased, the Ca-oxalate mass fraction, molecular mass, viscosity and thermal stability of the porang flour decreased. The acid and salt treatments did not change the FTIR patterns. The morphological analysis showed that the acid and salt treatments resulted in particles with rough surface and short crystal needles of Ca-oxalate. Soaking the porang slices in salt solution at a temperature of 55 °C was the most effective treatment to reduce the Ca-oxalate content of porang flour while retaining its other quality parameters.

Novelty and scientific contribution

The results of this study provided a comprehensive understanding of the effect of soaking porang slices in acid and salt solutions on the properties of the obtained porang flour. They can be used as scientific evidence on how to treat the porang slices to obtain the best quality of porang flour.

Recent advances in Artemisia argyi Levl. et Vant. polysaccharides: Extractions, purifications, structural characteristics, pharmacological activities, and existing and potential applications

Artemisia argyi Levl. et Vant. (A. argyi) is an important member of Asteraceae (Compositae) family, which has good medicinal potential and edible value. Phytochemical studies have shown that the A. argyi has a variety of bioactive components, mainly including polysaccharides, flavonoids, alkaloids, and volatile oil. More and more evidences show that A. argyi polysaccharide is a kind of representative pharmacological and biological active macromolecules, which has a variety of pharmacological activities in vitro and in vivo, such as estrogen-like effect, anti-bacterial, anti-tumor, anti-oxidant and immune regulation effect. As far as we know, there are few comprehensively reviews on A. argyi polysaccharide. This review aims to comprehensively and systematically review the research progress on the extractions and purifications, structural characteristics, pharmacological activities, structure-activity relationships, existing and potential applications of A. argyi polysaccharides in the past 12 years, in order to support their therapeutic potential and health functions. Finally, prospects were made for the further development and utilization of A. argyi polysaccharides in four fields: food, medicine, packaging materials, and daily chemicals.

Machine learning-aided enhancement of white tea extraction efficiency using hybridized GMDH models in microwave-assisted extraction

White tea is valuable for having a high antioxidant content, which is considered to possess numerous beneficial effects on health. This study investigated the application of microwave-assisted extraction (MAE) for the extraction of total phenolic compounds from white tea. The experimental setup included four independent variables: microwave power (ranging from 100 to 300 W), extraction time (ranging from 10 to 40 min), temperature (ranging from 35 to 50 °C), and the ratio of food to solvent (ranging from 0.25 to 0.5 g/10 mL). The responses that were evaluated were IC50 (ppm) and total phenolic content (mg/g). The experimental design consisted of thirty runs conducted within the MAE system. The group method of data handling (GMDH) models were used to predict important efficiency measures (IC50 and total phenol content) in the extraction process. The models were assessed based on their ability to capture the relationships between input conditions and efficiency outputs. Three GMDH variants were compared: baseline GMDH, GMDH optimized with a genetic algorithm (GMDH-GA), and GMDH optimized with a harmony search algorithm (GMDH-HS). While all models achieved high predictive ability on a test set, GMDH-HS emerged as the superior performer. It achieved near-perfect agreement with observations (d-index > 0.998), minimal errors (NRMSE < 0.02), and effectively captured data variance (NSE > 0.99) for both outputs. Correlation diagrams and Taylor diagrams confirmed the superior performance of GMDH-HS in terms of linearity, correlation, and error minimization. This study demonstrates the effectiveness of hybridizing GMDH with a harmony search algorithm for complex modeling tasks, paving the way for improved efficiency and yield optimization in extraction processes.

Hybrid machine learning approach integrating GMDH and SVR for heavy metal concentration prediction in dust samples

In agricultural regions prone to dust storms, heavy metal contamination of soil and crops from airborne particulates poses significant risks to food safety and public health. This study has assessed the potential of machine learning models for predicting concentrations of toxic heavy metals like arsenic, chromium, and lead in dust from the agricultural Sistan region of southeastern Iran. This region experiences frequent dust storms mobilizing particulates from local dried lakes onto agricultural lands. The metals including nickel, copper, magnesium, cobalt, zinc, chromium, arsenic, and lead were measured in summer dust samples during 2012-2018 across 15 stations. Two hybrid models were developed combining group method of data handling (GMDH) and support vector regression (SVR) machine learning with harmony search optimization (H) so as to predict toxic metals arsenic, chromium, and lead using nickel, copper, magnesium, cobalt, and zinc inputs. Standard error maps were uncertainty higher in southern and western areas, and they are most impacted by dust storms. Results demonstrated that the hybrid GMDH + H and SVR + H models improved the accuracy of individual GMDH and SVR models in predicting heavy metals. The GMDH + H model performed the best for the lead with an agreement index (d-index) of 0.98, root mean square error (RMSE) of 2.87 ppm, normalized RMSE (NRMSE) of 0.12, and coefficient of determination (RR) of 0.96. The SVR + H model showed the highest accuracy for arsenic and chromium, obtaining d-index 0.96, RMSE 0.47 ppm, NRMSE 0.09, and RR 0.92 for arsenic, and d-index 0.96, RMSE 11.24 ppm, NRMSE 0.16, and RR 0.93 for chromium. Taylor's diagram and heatmap analysis confirmed the superiority of the hybrid techniques. This work demonstrates the utility of state-of-the-art computing for addressing complex environmental health challenges.

A Comprehensive Review on Advanced Extraction Techniques for Retrieving Bioactive Components from Natural Sources

The extraction of bioactive components from natural sources has gained significant attention in recent years due to increasing demand for natural and functional constituents in various industries, including pharmaceuticals, food, and cosmetics. This review paper aims to provide a comprehensive overview of the studies on extracting bioactive components from natural sources using different advanced extraction techniques. It highlights the need for efficient extraction methods to preserve these components' integrity and bioactivity. Various extraction techniques as supercritical-fluid extraction, microwave-assisted extraction, ultrasound-assisted extraction, subcritical solvent extraction, and solid-phase microextraction are explored in detail, highlighting their principles, advantages, and limitations. The review further examines the impact of different factors on the extraction process, including solvent selection, extraction time, temperature, ultrasonication-amplitude, etc. Additionally, emerging techniques, such as green extraction methods and nanotechnology-based approaches, are discussed, emphasizing their potential to enhance the extraction efficiency and sustainability of the process. Furthermore, the review presents case studies and experimental results from recent research articles, providing insights into applying different extraction techniques for specific bioactive components, such as phenolics, flavonoids, alkaloids, and essential oils. It discusses the extraction yield, bioactivity, and potential utilization of the extracted components in various industries. Overall, this review paper is valuable for researchers, scientists, and industry professionals interested in extracting bioactive components from natural sources. It consolidates the current knowledge on different advanced extraction techniques, their optimization parameters, and their potential applications, facilitating further advancements in the field and the development of innovative extraction methods for bioactive component extraction from natural sources.

Investigation of Health Effects of Major Phenolic Compounds in Foods: Extraction Processes, Analytical Approaches and Applications

The escalating costs of healthcare services and a growing awareness of personal health responsibilities have led individuals to explore natural methods alongside conventional medicines for health improvement and disease prevention. The aging global population is experiencing increased health needs, notably related to conditions like diabetes, heart disease, and hypertension. Lifestyle-related diseases, poor dietary habits, and sedentary lifestyles underscore the importance of foods containing nutrients that can aid in preventing and managing these diseases. Phenolic compounds, a fundamental group of phytochemicals, are prominent in the chemical diversity of the natural world and are abundant in functional foods. Widely distributed in various plant parts, these compounds exhibit important functional and sensory properties, including color, taste, and aroma. Their diverse functionalities, particularly antioxidant activity, play a crucial role in mitigating cellular oxidative stress, potentially reducing damage associated with serious health issues such as cardiovascular disease, neurodegenerative disea23ses, and cancer. Phenolic compounds exist in different forms, some combined with glycosides, impacting their biological effects and absorption. Approximately 8000 polyphenols isolated from plants offer significant potential for natural medicines and nutritional supplements. Therefore, their extraction process and selective and sensitive food determination are very important. This review focuses on the extraction processes, analytical methods, and health effects of major phenolic compounds in foods. The examination encompasses a comprehensive analysis of analytical approaches and their applications in elucidating the presence and impact of these compounds on human health.

Effects of acetyl groups on the prebiotic properties of glucomannan extracted from Artemisia sphaerocephala Krasch seeds

This study explores the structural modification of glucomannan extracted from Artemisia sphaerocephala Krasch seeds (60S) to assess the impact of acetyl groups on its prebiotic characteristics. The structural changes were examined, with a focus on the degree of acetyl group substitution (DS). Both deacetylation and acetylation had limited influence on the molecular properties of 60S. Despite these modifications, the apparent viscosity of all samples remained consistently low. In vitro fermentation experiments revealed that Escherichia-Shigella decreased as DS increased, while Bacteroides ovatus was enriched. Acetylation had no significant impact on the utilization rate of 60S but led to a reduction in the production of propionic acid. Furthermore, untargeted metabolomics analysis confirmed the changes in propionic acid levels. Notably, metabolites such as N-acetyl-L-tyrosine, γ-muricholic acid, and taurocholate were upregulated by acetylated derivatives. Overall, acetyl groups are speculated to play a pivotal role in the prebiotic properties of 60S.

Bacillus megaterium: Evaluation of Chemical Nature of Metabolites and Their Antioxidant and Agronomics Properties

Bacillus megaterium is particularly known for its abundance in soils and its plant growth promotion. To characterize the metabolites excreted by this specie, we performed successive liquid/liquid extractions from bacteria culture medium with different polarity solvents (cyclohexane, dichloromethane, ethyl acetate and butanol) to separate the metabolites in different polarity groups. The extracts were characterized regarding their total phenolic content, the amount of reducing sugar, the concentration of primary amines and proteins, their chromatographic profile by HPLC-DAD-ELSD and their chemical identification by GC-MS. Among the 75 compounds which are produced by the bacteria, 19 identifications were for the first time found as metabolites of B. megaterium and 23 were described for the first time as metabolites in Bacillus genus. The different extracts containing B. megaterium metabolites showed interesting agronomic activity, with a global inhibition of seed germination rates of soya, sunflower, corn and ray grass, but not of corn, compared to culture medium alone. Our results suggest that B. megaterium can produce various metabolites, like butanediol, cyclic dipeptides, fatty acids, and hydrocarbons, with diverse effects and sometimes with opposite effects in order to modulate its response to plant growth and adapt to various environmental effects. These findings provide new insight into bioactive properties of this species for therapeutic uses on plants.