Optimization of enzyme-assisted preparation and characterization of Arenga pinnata resistant starch

Sustainable extraction of ligustilide and ferulic acid from Angelicae Sinensis Radix, for antioxidant and anti-inflammatory activities

The 2030 Agenda for Sustainable Development envisions a rational use of energy and resources in all technological processes. However, in the extraction methods of compounds from medicinal plants and herbs, there is an urgent to reduce the use of organic solvents and increase the energy efficiency of these methods. Therefore, a sustainable extraction method (enzyme and ultrasonic co-assisted aqueous two-phase extraction, EUA-ATPE) of simultaneous extraction and separation of ferulic acid and ligustilide from Angelicae Sinensis Radix (ASR) was developed by integrating enzyme-assisted extraction (EAE) with ultrasonic-assisted aqueous two-phase extraction (UAE- ATPE). The effects of different enzymes, extraction temperature, pH, ultrasonic time, liquid-to-materials ratio, etc., were optimized by single-factor experiments and central composite design (CCD). Under the optimum conditions, the highest comprehensive evaluation value (CEV) and extraction yield were obtained by EUA-ATPE. Furthermore, recovery (R), partition coefficient (K), and scanning electron microscopy (SEM) analysis revealed that enzyme and ultrasonic treatment improved mass transfer diffusion and increased the degree of cell disruption. Besides, the EUA-ATPE extracts have shown great antioxidant and anti-inflammatory activity in vitro. Finally, compared to different extraction methods, EUA-ATPE achieved higher extraction efficiency and higher energy efficiency due to the synergistic effect between EAE and UAE-ATPE. Therefore, the EUA-ATPE provides a sustainable method for extracting bioactive compounds from medicinal plants and herbs, contributing to Sustainable Development Goals (SDG), including SDG-6, SDG-7, SDG-9, SDG-12, and SDG-15.

Effect of autoclave-cooling cycles combined pullulanase on the physicochemical and structural properties of resistant starch from black Tartary buckwheat

A starch-rich portion is produced as a by-product of black Tartary buckwheat processing. The effect of enzymatic combined with autoclaving-cooling cycles (one, two, or three times) on the physicochemical and structural properties of black Tartary buckwheat type 3 resistant starch (BRS) was evaluated. The autoclaving-cooling cycles enhanced solubility and reduced swelling, with the BRS content increasing from 14.12% to 25.18%. The high crystallinity of the BRS reflected a high molecular order. However, increasing the number of autoclaving-cooling cycles did not result in higher BRS content. The highest BRS yield in the autoclaved starch samples was 25.18% after double-autoclaving-cooling cycles. Furthermore, the autoclaving-cooling cycles altered the crystalline structure of black Tartary buckwheat, and the subsequent crystallinity changed from 36.33% to 42.05% to 38.27%. Fourier-transform infrared spectroscopy shows that the number of cycles results in more efficient double-helical packing within the crystalline lamella. Principal component analysis showed that the autoclaving-cooling cycle treatment leads to significant changes in the molecular structure of resistant starch (RS). These results indicated that autoclaving-cooling cycles might be a feasible way for producing RS from black Tartary buckwheat starch with better structural stability to expand their application range.

Novel In Situ Modification for Thermoplastic Starch Preparation based on Arenga pinnata Palm Starch

Thermoplastic starch (TPS) has three main disadvantages, i.e., poor mechanical properties, low thermal stability and water sensibility. To overcome these disadvantages, TPS properties can be improved by starch modification, adding reinforcements and blending with other polymers. In this research, to prepare modified TPS, starch modification was carried out by in situ modification. The modified TPS was prepared by adding Arenga pinnata palm starch (APPS), glycerol and benzoyl peroxide simultaneously in the twin-screw extruder. Morphology analysis of TPS revealed that the starch granules were damaged and gelatinized in the extrusion process. No phase separation is observed in TPS, which exhibits that starch granules with and without benzoyl peroxide were uniformly dispersed in the matrix. The addition of benzoyl peroxide resulted in increased density of TPS from 1.37 to 1.39 g·cm^-3, tensile strength from 7.19 to 8.61 MPa and viscosity from 2482.19 to 2604.60 Pa.s. However, it decreased the elongation at break of TPS from 33.95 to 30.16%, melt flow rate from 7.13 to 5.73 gr/10 min and glass transition temperature from 65 to 52 °C. In addition, the thermal analysis showed that the addition of benzoyl peroxide increased the thermal stability of TPS and extended the temperature range of thermal degradation.

Arenga pinnata Resistant Starch Modulate Gut Microbiota and Ameliorate Intestinal Inflammation in Aged Mice

This study aimed to compare the regulatory effects of Arenga pinnata retrograded starch (APRS), Arenga pinnata starch (APS), and whole Arenga pinnata flour (APF) on gut microbiota and improvement of intestinal inflammation in aged mice. APF, APS, and APRS altered gut microbiota composition and exhibited different prebiotic effects. Bifidobacterium showed the greatest increase in feces of aged mice fed APF. The abundance of genus Lachnospiraceae_NK4A136 was highest in the APS group. APRS supplementation led to a greatest increasement in abundance of Lactobacillus, Roseburia, and Faecalibacterium prausnitzii. APRS induced significantly more short-chain fatty acid (SCFAs) production than APF and APS. APF, APS, and APRS treatments improved intestinal inflammation in aged mice and the order of ameliorative effect was APRS > APS > APF. APRS significantly decreased relative mRNA expression of pro-inflammatory cytokines (IL-6, IL-1β, and TNF-α) and increased anti-inflammatory cytokines (IL-10). In addition, APF, APS, and APRS significantly downregulated the relative mRNA expression of senescence-associated gene p53 and upregulated the expression of anti-aging gene Sirt1. These results provide potentially useful information about the beneficial effects of Arenga pinnata products on human health.

Anti-hyperlipidemic and ameliorative effects of chickpea starch and resistant starch in mice with high fat diet induced obesity are associated with their multi-scale structural characteristics

Chickpea starches were isolated from both untreated (UC-S) and conventionally cooked seeds (CC-S), and their multi-scale structural characteristics and in vivo physiological effects on controlling hyperlipidemia in high fat diet induced obese mice were compared with their corresponding resistant starch (RS) fractions obtained by an in vitro enzymatic isolation method (UC-RS and CC-RS). The degree of order/degree of double helix in Fourier transform infrared spectroscopy was in the following order: CC-RS > UC-RS > CC-S > UC-S, which was consistent with the trend observed for relative crystallinity and double helix contents monitored by X-ray diffractometer and solid-state ¹³C cross-polarization and magic angle spinning NMR analyses. The influence of different types of chickpea starch and their corresponding resistant starch fractions on regulating the serum lipid profile, antioxidant status, and histopathological changes in liver, colon and cecal tissues, and gene expressions associated with lipid metabolism, gut microbiota, as well as short-chain fatty acid metabolites in mice with high fat diet induced obesity was investigated. The results showed that the chickpea RS diet group exhibited overall better anti-hyperlipidemic and ameliorative effects than those of the starch group, and such effects were most pronounced in the CC-RS intervention group. After a six-week period of administration with chickpea starch and RS diets, mice in the UC-RS and CC-RS groups tended to have relatively significantly higher levels (P < 0.05) of butyric acid in their fecal contents. The 16S rRNA sequencing results revealed that mice fed with CC-RS showed the greatest abundance of Akkermansia and Lactobacillus compared with the other groups.

Optimization of ultrasonic-assisted enzymatic extraction of kiwi starch and evaluation of its structural, physicochemical, and functional characteristics

A new ultrasound-assisted enzymatic extraction (UAEE) method of starch from kiwifruit was established and optimized using response surface methodology (RSM). Under optimal conditions (the pectinase-to-cellulase-to-papain ratio = 1:2:1 g/kg, solid/liquid ratio = 1:6.68, extraction pH = 5.23, ultrasound power = 300 W, and extraction temperature = 52 °C), the kiwi starch (KS) yield was about 4.25%, and the starch content of KS was 873.23 mg/g. Compared to other extraction methods, UAEE can obtain KS with high yield and purity with a shorter extraction time and less solvent and enzyme. The extracted KS has a low gelatinization enthalpy (8.02 J/g) and a high peak viscosity (7933 cP), with obvious particle properties and low adhesion. In addition, KS is rich in polyphenols, has strong antioxidant activity, and has higher contents of amylose starch (30.74%) and resistant starch (60.18%). This study established a novel and highly efficient method for KS extraction and suggest several possible applications for KS in the food industry.