Effect of particle size on phytochemical composition and antioxidant properties of Sargassum cristaefolium ethanol extract

Extraction of polyphenols and essential oils from herbs with green extraction methods - An insightful review

The demand for polyphenols and essential oils (EOs) on the food market is high and grows every year. Its partially the result of the fact that these compounds can be used in formulation of clean label foods, a fast growing food sector. A significant share of polyphenols and EOs are extracted from herbs. The quality of the extracts is determined mainly by the extraction method. Conventional extraction techniques of phytochemicals are time-consuming, operate at high temperatures, and require usage of organic solvents and energy in large quantities. According to the United Nations Sustainability Development Plan, chemical processes should be replaced by green alternatives that would reduce the use of solvents and energy. Ultrasound-Assisted Extraction (UAE), Microwave-Assisted Extraction (MAE) and Cold Plasma-Assisted Extraction (CPAE) meets these criteria. The review shows that each of these techniques seems to be a great alternative for conventional extraction methods ensuring higher yields of bioactive compounds.

Comparative phytochemical profile and biological activity of three Terminalia species as alternative antimicrobial therapies

Ethnopharmacological relevance

Medicinal plants can help combat antibiotic resistance by providing novel, active molecules. Three plant species of the Terminalia genus are widely used in traditional medicine in the Mouhoun region for the treatment of cutaneous and respiratory diseases. Therefore, it is important to determine the ethnopharmacological potential of bark extracts from the trunks of these three Terminalia species.

Aim of the study

This study compared the phytochemical and biological activities of extracts from three Terminalia species to determine their ethnopharmacology.

Materials and methods

The medicinal properties of the extracts were assessed based on their ability to inhibit the growth of the following microorganisms: Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Candida albicans, Candida krusei, Candida glabrata, and Candida tropicalis. The significant interest in these medicinal plants among the local communities were elucidated by their antioxidant properties and phytochemical composition, along with the detection key bioactive compounds. Major phytochemical groups and phenolic compounds were determined using high-performance liquid chromatography with a diode array detector. These phytochemical findings were validated by evaluating the antioxidant capacity of the extracts using DPPH, FRAP, and ABTS assays.

Results

Hydroethanolic, ethanolic, and hexane extracts from the bark of three Terminalia species inhibited the growth of both bacteria and fungi, as evidenced by their minimum inhibitory concentrations (MICs).The findings showed that Terminalia species were most effective against various tested bacteria and fungi, with MICs ranging from 0.1 to 6.25 mg/mL. Terminalia avicennioides, Terminalia macroptera, and Terminalia laxiflora extracts demonstrated 50 % inhibition of DPPH at concentrations ranging from 0.04 to 0.6 mg/mL. Phytochemical analysis revealed the presence of several families of chemical compounds, such as total phenolics and flavonoids. Phenolic compounds identified by HPLC in ethanolic extracts of T. avicennioides, such as isorhamnetin, quercetin, and ferulic acid, are recognised for their antimicrobial and antioxidant properties.

Conclusion

These findings establish an ethnobotany for these three Terminalia species, with their chromatographic characteristics facilitating the identification of key molecules of interest. The ethanolic extract of T. avicennioides can be used in phytomedicinal formulations against bacterial (P. aeruginosa and S. aureus) and fungal (C. albicans and C. glabrata) infections, both of which are recurrently recorded in certain skin and respiratory tract diseases.

Extraction of bioactive compounds from pecan nutshell: An added-value and low-cost alternative for an industrial waste

The pecan nutshell [Carya illinoinensis (Wangenh) C. Koch] (PNS) is a source of bioactives with important beneficial properties for the human health. PNS represents between 40-50 % of total mass of the nut, resulting as waste without any added value for the food industry. Even though a variety of methods were already developed for bioactive extraction from this waste, unconventional methodologies, or those which apart from green chemistry principles, were discarded considering the cost of production, the sustainable development goals of United Nations and the feasibility of real inclusion of the technology in the food chain. Then, to add-value to this waste, a low-cost, green and easy-scalable extraction methodology was developed based on the determination of seven relevant factors by means of a factorial design and a Response Surface Methodology, allowing the extraction of bioactives with antioxidant capacity. The pecan nutshell extract had a high concentration of phenolic compounds (166 mg gallic acid equivalents-GAE/g dry weight-dw), flavonoids (90 mg catechin equivalent-CE/g dw) and condensed tannins (189 mg CE/g dw) -related also to the polymeric color (74.6 %)-, with high antioxidant capacities of ABTS+. radical inhibition (3665 µmol Trolox Equivalent-TE/g dw) and of iron reduction (1305 µmol TE/g dw). Several compounds associated with these determinations were identified by HPLC-ESI-MS/MS, such as [Epi]catechin-[Epi]catechin-[Epi]gallocatechin, myricetin, dihydroquercetins, dimers A and B of protoanthocyanidins, ellagitannins and ellagic acid derivatives. Hence, through the methodology developed here, we obtained a phenolic rich extract with possible benefits for human health, and of high industrial scalability for this co-product transformation.

Influence of coffee roasting degree on antioxidant and metabolic parameters: Comprehensive in vitro and in vivo analysis

This study aimed to assess the impact of roasting degree on antioxidant and metabolic parameters in vitro and in vivo. In vitro, we evaluated radical scavenging, lipid peroxidation, and the activity of digestive enzymes (α-glucosidase, α-amylase, and lipase). In vivo, we first examined coffee's effect on carbohydrate and lipid absorption in healthy rats, followed by a chronic evaluation of metabolic disorders and antioxidant markers using a diet-induced obesity model. In vitro results revealed that increased roasting degree reduced the antioxidant capacity of coffee brews. All brews showed lower inhibition of α-glucosidase and α-amylase, and lipase inhibition compared to the positive control (acarbose or orlistat). In vivo, all roasting degrees consistently reduced postprandial glucose levels by 20%. Notably, coffee with a high roasting degree (HRD) decreased serum triglycerides (TG) by ∼44% after a lipid load, while other roasts did not. Chronic administration of unroasted (UN) or HRD coffee significantly reduced weight gain compared to the obese control (∼15% and ∼10%, respectively). Notably, all coffee samples improved lipid metabolism parameters. UN and HRD coffee significantly decreased adipocyte volume by 58% and 48%, respectively, compared to the obese control. Additionally, all groups exhibited less than 30% hepatic lipid droplets independent of roasting degree. HRD treatment notably increased liver catalase (CAT) activity and reduced lipid peroxidation in serum (∼90%), liver (∼59%), and adipose tissue (∼37%) compared to the obese control group. These findings suggest that HRD in coffee may confer certain biological advantages.

Low-temperature pulverization-specific Sargassum horneri extract accelerates wound healing and attenuates inflammation in a mouse burn model

Burn injuries, affecting local skin disruption as well as inducing systemic inflammatory responses, are presented as a global public health problem. To enhance the effects of burn wound healing, treatment must simultaneously regulate both re-epithelialization and hyperinflammation. Extracts of Sargassum horneri (S. horneri) have shown a potential to enhance skin wound healing through antioxidative properties, immune enhancement, and modulation of inflammatory responses. However, despite its promising application for burn wound healing, specific investigation into S. horneri-derived compounds for enhancing wound healing has not yet been conducted. In this research, we investigated the burn wound-healing effect of the low-temperature pulverization-specific S. horneri extract (LPSHE), which could not be detected using the room-temperature grinding method. In a mouse burn model with third-degree burn injuries, LPSHE accelerated re-epithelialization by promoting the increase in F-actin formation and reduced burn-induced ROS levels. Additionally, LPSHE significantly regulated hyperinflammation by reducing pro-inflammatory cytokines. Further investigation into molecular mechanisms using HaCaT keratinocytes also demonstrated beneficial effects on burn wound healing. Taken together, our findings suggested that LPSHE is a promising therapeutic candidate for enhancing burn wound healing. Furthermore, this research underscored the importance of low-temperature pulverization in discovering novel natural compounds from marine organisms.

The Development and Pre-Clinical Anti-Inflammatory Efficacy of a New Transdermal Ureasil-Polyether Hybrid Matrix Loaded with Flavonoid-Rich Annona muricata Leaf Extract

This study aimed to develop a novel ureasil-polyether transdermal hybrid matrix (U-PEO) loaded with Annona muricata concentrated extract (AMCE), which exhibits potent anti-inflammatory activity. The extract was obtained by maceration, a method that allowed for the extraction of a high concentration of flavonoids (39.27 mg/g of extract). In vivo tests demonstrated that 10 mg/kg of AMCE inhibited inflammation for 6 h. The physicochemical characterization of U-PEO with AMCE was conducted via a thermogravimetric analysis (TGA), while its surface was recorded using atomic force microscopy (AFM). The in vitro macroscopic swelling and release tests demonstrated the hydrophilic profile of the material and the percentage of AMCE released. The TGA results demonstrated that the system exhibited physical compatibility due to the thermal stability of U-PEO. Additionally, the AFM analysis revealed a rough and porous surface, with a particular emphasis on the system with AMCE. The release resulted in the liberation of 23.72% of AMCE within 24 h. Finally, the preclinical tests demonstrated that U-PEO with AMCE was also capable of effectively inhibiting inflammation for 6 h, a duration comparable to that of a commercial formulation. The results permit the advancement of the study towards the development of a transdermal system, thereby rendering its application in clinical studies feasible.

FT-IR-based fingerprint combined with unsupervised chemometric analysis revealed particle sizes and aqueous-ethanol ratio alter the chemical composition and nutraceutical value of Daucus carota

This study reported the effects of particle size of dry powder and the optimum solvent extraction on the nutraceutical value of carrot by observing its FT-IR fingerprint, TPC, TFC, and antioxidant activity. The dried-powdered carrot was ultrasound-assisted extracted using EtOH, water, and EtOH-water. The TFC, TPC, and antioxidant activity were analysed by a colorimetric method using a spectrophotometry UV-Vis. The chemotaxonomy of samples was analysed using FT-IR combined with chemometrics analysis. The TFC, TPC, and antioxidant capacity were significantly different for each sample with the highest TFC, TPC, and antioxidant obtained on particle size 149 μm with EtOH-water (50:50) as the most prominent solvent (19.51 mgQE/g, 9.90 mgGAE/g, IC50: 16.7 ± 0.89 µg/mL). FT-IR profiling of samples also illustrates a minor different pattern of the spectrum, indicating there is a difference in their chemical composition. The particle size and EtOH-water ratio influence the chemical composition and antioxidant activity of carrots.

Evaluation of the Nutritional Value of Prunus dulcis Blossoms and the Antioxidant Compounds of Their Extracted Oil Using Green Extraction Method

Edible blossoms and extracted oils from various parts of plants have gained the interest of researchers in recent years due to their strong antioxidant activity and their high content of vitamins. In addition, they contain a plethora of polyphenols, and they do not have high caloric content. The blossoms of Prunus dulcis (i.e., almond tree) are edible; however, they have not been examined in terms of nutritional value. The present study aimed to examine the nutritional value of almond blossoms, as well as their extracted oil. The fat content of the blossoms was 1.75 g/100 g dry weight (dw), while the defatted blossoms were found to contain 1.34 g/100 g dw of crude protein and 29.97 g/100 g dw of carbohydrates. In addition, the blossom oil was tested for its composition of fatty acids, polyphenols, and total carotenoids. According to the results, several important fatty acids for human health were identified, such as oleic (25.17%), linoleic (15.64%), and linolenic (10.15%). Simultaneously, a low oxidation index (COX), i.e., 4.05, and many monounsaturated (25.17%) and unsaturated (67.56%) fats were detected, while both polyphenols (51.86 mg GAE/kg) and carotenoids were in abundance. Finally, the combination of simple stirring with ultrasound (a green extraction method) was found to be the most appropriate method to ensure maximum amounts of various antioxidant compounds in the blossom extracts (i.e., polyphenols and L-ascorbic acid). After optimization, the total polyphenol content increased by 23.98% and L-ascorbic acid content by 6.96%. In addition, antioxidant activity was tested by different antioxidant assays and specifically FRAP, DPPH, and H2O2, which showed a corresponding increase (14.46, 17.23, and 8.79%, respectively). Therefore, it can be concluded that Prunus dulcis blossoms, besides being edible, are also highly nutritious, and their oil has nutritional value and deserves further exploration.

Size Matters: Influence of Particle Size on Antioxidant, β-Glucan, and Anti-Inflammatory Potential in Pleurotus floridanus (Agaricomycetes)

Cellular damage resulting from elevated levels of free radicals can lead to persistent health issues. Pleurotus floridanus, an edible white oyster mushroom, is rich in β-glucans with potent antioxidant and anti-inflammatory properties. In this research, we examined the β-glucan content, total phenolic content, as well as antioxidant and anti-inflammatory potential of hot water extracts with varying particle sizes (< 75, 75-154, 154-300, and 300-600 μm) of both whole and sliced fruiting bodies of P. floridanus. The findings revealed that the в-glucan content increased as the particle size increased, although no significant differences were observed. Conversely, smaller particle sizes (< 75 μm) of whole and sliced fruiting bodies of P. floridanus exhibited higher phenolic content, 2,2-diphenyl-1-picryl-hy-drazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging activity, and reducing ability compared with larger particle size (> 75 μm). Of the four samples (AW2, AW3, AS1, and AS2) with the highest antioxidant activity selected for anti-inflammatory assays, all demonstrated the ability to reduce nitric oxide and tumor necrosis factor-alpha levels, but did not enhance interleukin-10 expression in lipopolysaccharide-stimulated RAW264.7 cells. Interestingly, particle size < 75 to 300 μm did not appear to influence the anti-inflammatory activity, because no significant differences were observed among the particle sizes. Therefore, a particle size < 300 μm in a P. floridanus hot water extract could serve as a valuable source of antioxidant and anti-inflammatory compounds to counteract the harmful effects of free radicals.

Impact of Grinding and Sorting Particle Size on Phytochemical Yield in Dipterocarpus alatus Leaf Extract

The main objective of this study was to investigate the impact of grinding (pretreatment) with a pin mill on the crude extract yields of Dipterocarpus alatus (Yang-Na) leaves. A factorial design in a completely randomized design was conducted to study the combinational effects of sieve sizes (1.0, 1.5, and 3.0 mm) and feed rates (1.0, 1.5, and 3.0 kg min-1), examining the interaction of parameters for grinding oven-dried Yang-Na leaves. Ethanol extraction initially evaluated the influence of Yang-Na leaf powder with diverse particle sizes. When sorting particle size, the crude extract yield increased as the particle size decreased, with 0.038-0.150 mm particles yielding the highest extraction, although yields decline when the particle size is lower than 0.038 mm. The average particle sizes, production capacity, and fineness modulus all exhibited a significant decrease as the sieve size and feeding rate were reduced, while the specific energy consumption showed an inversely proportional relationship with these parameters. Intriguingly, the crude extract yield remained independent of the average particle size. Notably, the highest yield (14.79 g kg-1) was derived from a 0.31 mm average particle size, ground with a 1.5 mm sieve and a 3 kg min-1 feeding rate. This suggests that the pretreatment, involving both grinding conditions and sorting size, has an impact on the performance of the extraction process. However, this study offers an energy-efficient alternative, advocating for using average particle sizes without prior sorting, streamlining the extraction process while maintaining substantial yields. These insights underline the crucial influence of particle size and grinding techniques, advancing our understanding of efficient herbal extraction techniques for industrial applications.

Influence of Particle Size and Extraction Methods on Phenolic Content and Biological Activities of Pear Pomace

The main goal of this research was to investigate how particle size influences the characteristics of pear (Pyrus Communis L.) pomace flour and to examine the impact of different pre-treatment methods on the phenolic content and associated bioactivities. Pear pomace flour was fractionated into different particle sizes, namely 1 mm, 710 µm, 180 µm, 75 µm and 53 µm. Then two extraction methods, namely maceration with methanol and two-step extraction with hexane via Soxhlet followed by ultrasound extraction with methanol, were tested. Total phenolic and total flavonoid contents ranged from 375.0 to 512.9 mg gallic acid/100 g DW and from 24.7 to 34.6 mg quercetin/100 g DW, respectively. Two-step extraction provided antioxidant activity up to 418.8 (in FRAP assay) and 340.0 mg Trolox/100 g DW (in DPPH assay). In order to explore various bioactive properties, this study assessed the inhibitory effects of enzymes, specifically α-amylase and β-glucosidase (associated with antidiabetic effects), as well as angiotensin-converting enzyme (linked to potential antihypertensive benefits). Additionally, the research investigated antibacterial potential against both Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria, revealing significant results (p < 0.05), particularly in the case of the two-step extraction method. This investigation underscores the substantial value of certain food industry wastes, highlighting their potential as bioactive ingredients within the framework of a circular economy.

In Vitro Anti-Oxidant, In Vivo Anti-Hyperglycemic, and Untargeted Metabolomics-Aided-In Silico Screening of Macroalgae Lipophilic Extracts for Anti-Diabetes Mellitus and Anti-COVID-19 Potential Metabolites

COVID-19 patients with comorbid DM face more severe outcomes, indicating that hyperglycemic conditions exacerbate SARS-CoV-2 infection. Negative side effects from existing hyperglycemia treatments have urged the need for safer compounds. Therefore, sourcing potential compounds from marine resources becomes a new potential approach. Algal lipids are known to possess beneficial activities for human health. However, due to limitations in analyzing large amounts of potential anti-hyperglycemic and anti-COVID-19-related marine metabolites, there is an increasing need for new approaches to reduce risks and costs. Therefore, the main aim of this study was to identify potential compounds in macroalgae Sargassum cristaefolium, Tricleocarpa cylindrica, and Ulva lactuca lipophilic extracts for treating DM and COVID-19 by an integrated approach utilizing in vitro anti-oxidant, in vivo anti-hyperglycemic, and metabolomic-integrated in silico approaches. Among them, S. cristaefolium and T. cylindrica showed potential anti-hyperglycemic activity, with S. cristaefolium showing the highest anti-oxidant activity. A GC-MS-based untargeted metabolomic analysis was used to profile the lipophilic compounds in the extracts followed by an in silico molecular docking analysis to examine the binding affinity of the compounds to anti-DM and anti-COVID-19 targets, e.g., α-amylase, α-glucosidase, ACE2, and TMPRSS2. Notably, this study reveals for the first time that steroid-derived compounds in the macroalgae T. cylindrica had higher binding activity than known ligands for all the targets mentioned. Studies on drug likeliness indicate that these compounds possess favorable drug properties. These findings suggest the potential for these compounds to be further developed to treat COVID-19 patients with comorbid DM. The information in this study would be a basis for further in vitro and in vivo analysis. It would also be useful for the development of these candidate compounds into drug formulations.

Physicochemical Composition and Antioxidant Activity of Five Gari Processed from Cassava Roots (Manihot esculenta Crantz) Harvested at Two Different Maturity Stages and Two Seasons

Gari is a partially gelatinized roasted fermented granular white or yellowish product made from storage roots of cassava. It is consumed as fast foods in many countries across the world. Physicochemical composition, particle size, colour, and antioxidant activities of five gari (92/0326, 96/1414, IRAD4115, EN, and AD) processed from fresh storage roots harvested at 12 months after planting (MAP) and 15MAP compared to four (4) commercial gari (M1, M2, M3, and M4) were evaluated. The analytical results revealed that colour value b∗ and particle size varied significantly (p < 0.05) among the gari samples. Bound flavonoid contents were lower than free flavonoids (3.93 to 10.50 mgQE/100 g and 2.40 to 8.85 mgQE/100 g, respectively). Fourier transform infrared confirmed the functional groups in all gari samples. The antioxidant activity of the bound phenolics showed significantly (p < 0.05) higher DPPH scavenging ability than free phenolics (gari M2: 2.70 μgTE/g). Similarly, the bound phenolics showed significant (p < 0.05) variation of HRSA scavenging activity (0.18-35.09 μgTE/g). However, the best HRSA scavenging activity was found with bound phenolics of gari 96/1414, whereas HRSA scavenging activity was not detected in gari 92/0326, 96/1414, and AD. The value of ABTS scavenging activity of gari varied significantly (p < 0.05) from 20.60 to 30.17 μgTE/g and from 20.70 to 34.39 for free and bound phenolics, respectively, while free phenolics showed higher FRAP value (7.97 mgTE/g) than the bound phenolics (4.59 mgTE/g). Additionally, phenolics and antioxidant activities showed significantly (p < 0.05) a positive correlation. The present study has provided an insight into the physicochemical composition, bioactive compounds, and antioxidant activities of various gari processed at different season and maturity period of harvesting. It reveals that consumers of cassava gari can get health benefits apart from the nutritional values.

Variation of the Nutritional Composition and Bioactive Potential in Edible Macroalga Saccharina latissima Cultivated from Atlantic Canada Subjected to Different Growth and Processing Conditions

Macroalgae are a new food source in the Western world. The purpose of this study was to evaluate the impact of harvest months and food processing on cultivated Saccharina latissima (S. latissima) from Quebec. Seaweeds were harvested in May and June 2019 and processed by blanching, steaming, and drying with a frozen control condition. The chemical (lipids, proteins, ash, carbohydrates, fibers) and mineral (I, K, Na, Ca, Mg, Fe) compositions, the potential bioactive compounds (alginates, fucoidans, laminarans, carotenoids, polyphenols) and in vitro antioxidant potential were investigated. The results showed that May specimens were significantly the richest in proteins, ash, I, Fe, and carotenoids, while June macroalgae contained more carbohydrates. The antioxidant potential of water-soluble extracts (Oxygen Radical Absorbance Capacity [ORAC] analysis-625 µg/mL) showed the highest potential in June samples. Interactions between harvested months and processing were demonstrated. The drying process applied in May specimens appeared to preserve more S. latissima quality, whereas blanching and steaming resulted in a leaching of minerals. Losses of carotenoids and polyphenols were observed with heating treatments. Water-soluble extracts of dried May samples showed the highest antioxidant potential (ORAC analysis) compared to other methods. Thus, the drying process used to treat S. latissima harvested in May seems to be the best that should be selected.

Effect of Different Drying Treatments and Sieving on Royal Gala Apple Pomace, a Thickening Agent with Antioxidant Properties

Currently, there is an increasing interest in the search of natural derived materials as valuable substitutes for microplastics. One of the categories investigated, represented by thickening agents deriving from agri-food waste and apple pomace (AP), was considered of interest. In this study AP was submitted to three different treatments and drying conditions (oven drying at 55 °C for 12 h; homogenization and oven drying at 55 °C for 12 h; homogenization and freeze-drying), and then grinded and sieved obtaining three different dimensional fractions (>400 µm, 250-400 µm and <250 µm). The hydroalcoholic extracts of these fractions, obtained by ultrasound-assisted extraction, were analyzed to compare their total phenol content (TPC), antioxidant properties, and phenol profile. Correlation studies between the above-indicated parameters were also carried out. The highest values of TPC, antioxidant capacity, and phenol content (determined by liquid chromatography) were found for oven dried AP (250-400 μm) or homogenized and freeze-dried (>400 μm) samples. Both samples were most suitable to form stable hydrogels and the sample obtained after drying at 55 °C showed the best performances in terms of ability to form a stable hydrogel. Among the studied treatments and drying conditions, the oven dried AP was demonstrated to be an interesting stabilizing material with potential applications in many fields (such as food, cosmetics, and nutraceuticals) showing both antioxidant activity and thickening capacity.

Brown Macroalgae Sargassum cristaefolium Extract Inhibits Melanin Production and Cellular Oxygen Stress in B16F10 Melanoma Cells

The brown macroalgae Sargassum has been reported for its anti-UV and photoprotective potential for industrial applications. This study evaluated the melanin inhibition activity of Sargassum cristaefolium (SCE) ethanol extract. Melanogenesis inhibition by SCE was assessed in vitro with B16-F10 melanoma cell models and in silico against melanin regulatory proteins Tyrosinase (TYR) and Melanocortin 1 Receptor (MC1R). The regulatory properties evaluated were the melanin content, intracellular tyrosinase activity and cellular antioxidant activities. In addition, the bioactive compounds detected in SCE were subjected to molecular docking against TYR and MC1R. Based on the results, 150 µg/mL SCE effectively inhibited the production of melanin content and intracellular tyrosinase activity. Cellular tyrosinase activity was reduced by SCE-treated cells in a concentration-dependent manner. The results were comparable to the standard tyrosinase inhibitor kojic acid. In addition, SCE effectively decreased the intracellular reactive oxygen species (ROS) levels in B16-F10 cells. The antioxidant properties may also contribute to the inhibition of melanogenesis. In addition, LCMS UHPLC-HR-ESI-MS profiling detected 33 major compounds. The results based on in silico study revealed that the bioactive compound putative kaurenoic acid showed a strong binding affinity against TYR (-6.5 kcal/mol) and MC1R (-8.6 kcal/mol). However, further molecular analyses are needed to confirm the mechanism of SCE on melanin inhibition. Nevertheless, SCE is proposed as an anti-melanogenic and antioxidant agent, which could be further developed into cosmetic skin care products.

Multivariate Analysis Revealed Ultrasonic-Assisted Extraction Improves Anti-Melanoma Activity of Non-Flavonoid Compounds in Indonesian Brown Algae Ethanol Extract

Indonesia has high biodiversity of algae that are under-utilised due to limitations in the processing techniques. Here, we observed the effect of two different extraction methods (cold maceration and ultrasonic-assisted extraction (UAE)) on multiple variables of Indonesian brown algae ethanol extracts (Sargassum polycystum, Sargassum cristaefolium, Sargassum aquifolium and Turbinaria ornata). The variables observed included metabolites screening by untargeted metabolomics liquid chromatography-high-resolution mass spectrometry (LC-HRMS), observation of total phenolic content (TPC), total flavonoid content (TFC), anti-oxidant and B16-F10 melanoma cells cytotoxicity. UAE extracts had higher extraction yield and TPC, but no TFC difference was observed. UAE extract had more lipophilic compounds, such as fatty acids (Palmitic acid, Oleamide, Palmitoleic acid, Eicosapentaenoic acid, α-Linolenic acid, Arachidonic acid), lipid-derived mediators (11,12-Epoxyeicosatrienoic acid ((±)11(12)-EET)), steroid derivatives (Ergosterol peroxide), lipophilic metabolite (Fucoxanthin), and lipid-soluble vitamins (all-trans-retinol). Principle component analysis (PCA) revealed that TPC, not TFC, in the UAE extracts was correlated with the anti-oxidant activities and cytotoxicity of the extracts towards B16-F10 melanoma cells. This means other non-flavonoid phenolic and lipophilic compounds may have contributed to its bioactivity. These results suggest that out of the two methods investigated, UAE could be a chosen method to extract natural anti-melanogenic agents from brown algae.

High Levels of Policosanols and Phytosterols from Sugar Mill Waste by Subcritical Liquefied Dimethyl Ether

Extracting nutraceuticals with high value from bagasse, filter mud, and sugarcane leaves discarded as sugar mill by-products, is crucial for the development of a sustainable bio-economy. These by-products are important sources of policosanols and phytosterols, which have a cholesterol-lowering effect. This research focused on using a promising green technology, subcritical liquefied dimethyl ether extraction, with a low pressure of 0.8 MPa, to extract policosanols and phytosterols and on application of pretreatments to increase their contents. For direct extraction by subcritical liquefied dimethyl ether without sample pretreatment, the highest extraction yield (7.4%) and policosanol content were found in sugarcane leaves at 2888 mg/100 g, while the highest and lowest phytosterol contents were found in filter mud at 20,878.75 mg/100 g and sugarcane leaves at 10,147.75 mg/100 g, respectively. Pretreatment of filter mud by ultrasonication in hexane solution together with transesterification before the second subcritical liquefied dimethyl ether extraction successfully increased the policosanol content, with an extract purity of 60%, but failed to increase the phytosterol content.

Macroalgae Bioactive Compounds for the Potential Antiviral of SARS-CoV-2: An In Silico Study

Coronavirus disease (COVID-19), which was due to novel coronavirus was detected in December 2019 in Wuhan, China for the first time and spread rapidly became a global pandemic. This study aimed to predict the potential of macroalgae compounds as SARS-CoV-2 antiviral by inhibiting of ACE2 receptor through in silico approach. Twenty-seven macroalgae compounds were obtained from PubChem (NCBI, USA), while target protein ACE2 receptor was collected from Protein Data Bank (PDB). Then the initial screening study drug-likeness conducted by Lipinski rule of five web server and prediction of bioactive probability carried out by PASS (Prediction of activity spectra for biologically active substances) Online web server. After those compounds were approved by Lipinski’s rule of five and PASS online prediction web server, the blind docking simulation was performed using PyRx 0.8 software to show binding energy value. Molecular interaction analysis was done using BIOVIA Discovery Studio 2016 v16.1.0 and PyMOL v2.4.1 software. There are six macroalgae compounds approved by Lipinski’s rule of five and PASS Online Analysis. The result is that macroalgae compound siphonaxanthin among 27 macroalgae compound showed strong binding energy to bind ACE2 receptor with -8.8 kcal/mol. This study also used the SARS-CoV-2 drugs as positive control: remdesivir, molnupiravir, baricitinib, lopinavir, oseltamivir, and favipiravir. The result shows that siphonaxanthin has lowest binding energy than the common SARS-CoV-2 drug. Macroalgae compounds are predicted to have potential as SARS-CoV-2 antiviral. Thus, extension studies need to investigate by in vitro and in vivo analysis for confirmation the siphonaxanthin’s inhibitory activity in combat SARS-CoV-2.

Trial Protocol for Evaluating Platforms for Growing Microgreens in Hydroponic Conditions

The hydroponic production of microgreens has potential to develop, at both an industrial, and a family level, due to the improved production platforms. The literature review found numerous studies which recommend procedures, parameters and best intervals for the development of microgreens. This paper aims to develop, based on the review of the literature, a set of procedures and parameters, included in a test protocol, for hydroponically cultivated microgreens. Procedures and parameters proposed to be included in the trial protocol for evaluating platforms for growing microgreens in hydroponic conditions are: (1) different determinations: in controlled settings (setting the optimal ranges) and in operational environments settings (weather conditions in the area/testing period); (2) procedures and parameters related to microgreen growth (obtaining the microgreens seedling, determining microgreen germination, measurements on the morphology of plants, microgreens harvesting); (3) microgreens production and quality (fresh biomass yield, dry matter content, water use efficiency, bioactive compound analysis, statistical analysis). Procedures and parameters proposed in the protocol will provide us with the evaluation information of the hydroponic platforms to ensure: number of growing days to reach desired size; yield per area, crop health, and secondary metabolite accumulation.