Microwave-Assisted Desulfation of the Hemolytic Saponins Extracted from Holothuria scabra Viscera

Saponins are plant and marine animal specific metabolites that are commonly considered as molecular vectors for chemical defenses against unicellular and pluricellular organisms. Their toxicity is attributed to their membranolytic properties. Modifying the molecular structures of saponins by quantitative and selective chemical reactions is increasingly considered to tune the biological properties of these molecules (i) to prepare congeners with specific activities for biomedical applications and (ii) to afford experimental data related to their structure–activity relationship. In the present study, we focused on the sulfated saponins contained in the viscera of Holothuria scabra, a sea cucumber present in the Indian Ocean and abundantly consumed on the Asian food market. Using mass spectrometry, we first qualitatively and quantitatively assessed the saponin content within the viscera of H. scabra. We detected 26 sulfated saponins presenting 5 different elemental compositions. Microwave activation under alkaline conditions in aqueous solutions was developed and optimized to quantitatively and specifically induce the desulfation of the natural saponins, by a specific loss of H2SO4. By comparing the hemolytic activities of the natural and desulfated extracts, we clearly identified the sulfate function as highly responsible for the saponin toxicity.

Increased Tea Saponin Content Influences the Diversity and Function of Plantation Soil Microbiomes

Plant secondary metabolites (PSMs) contained in plant litter will be released into soil with the decomposition process, which will affect the diversity and function of soil microbiomes. The response of soil microbiomes to PSMs in terms of diversity and function can provide an important theoretical basis for plantations to put forward rational soil ecological management measures.

Identification of Phytochemicals from the Water Extract of Eurycoma longifolia Roots using Solid-Liquid and Liquid-Liquid Extraction Based Fractionation Techniques

Phytochemicals in the water extract of Eurycoma longofolia roots were identified using both solid-liquid and liquid-liquid extraction based fractionation techniques. A reversed phase C18 solid phase extraction (SPE) was used as solid-liquid extraction, whereas solvent partition was applied as liquid-liquid extraction. Total saponin was increased after fractionation. A few known quassinoids; eurycomanone, 13α(21)-epoxyeurycomanone, pasakbumin D, 13β,18-dihydroeurycomanol and 13β,21-dihydroxyeurycomanol were identified from the 40% and 60% methanol fractions of SPE. Solvent partition extract using ethyl acetate was found to have the highest saponin content compared to butanol and chloroform fractions. Subsequent acetone precipitation of the organic fractions recovered a formylated hexose trimer and other saccharide-containing compounds. Ethyl acetate effectively recovered saponins from E. longofolia water extract using liquid-liquid extraction followed by acetone precipitation.

Nutrient and Anti-Nutrient Composition of Four Rice Varieties in Port Harcourt Metropolis

This study evaluated the nutrient and anti-nutrient content of four rice varieties in Port Harcourt metropolis. Four rice varieties (Tomato gold TG, Mama’s pride MP, Ultimate gold UG and daily choice DC) were used in this study. The rice varieties were purchased, milled into fine flour and evaluated for proximate, mineral and anti-nutrient analysis using standard methods. Proximate composition of the rice varieties revealed that moisture content ranged from 11.51-12.80%, ash (0.45-0.60%), fat (0.39-1.39%), crude protein (5.73-6.07%), crude fibre (0.90-6.85%) and carbohydrate (73.67-80.09%). Mama’s pride rice variety contained higher ash and fat contents while Tomatoes gold had significantly higher crude fibre. On the other hand, ultimate gold rice variety contained higher protein and carbohydrate; however, ash, protein and moisture contents did not vary significantly (p>0.05) between the rice varieties. Mineral composition of the rice varieties also showed that magnesium content ranged from 6.28-9.63 mg/100 g, calcium (3.74-8.23mg/100g) and iron (1.50-5.48mg/100g). The concentration of these mineral elements was found to be superior in ultimate gold rice variety. Phenol content of the rice varieties ranged from 9.92-14.58mg/100g, phytate (1.22-1.53g/kg), saponin (5.86-6.37%), tannin (47.03-66.89 mg/100 g) and flavonoid (2.29-2.80%). Ultimate gold rice variety also contained higher concentrations of phenol and tannins while saponin content was higher in daily choice rice variety. Phytate content on the other hand did not vary significantly (p>0.05) between the rice varieties. The result therefore revealed that ultimate gold rice variety contained a considerable amount of nutrients and should be highly recommended to consumers for derivation of the above-mentioned nutrients.

Yield and Nutritional Characterization of Thirteen Quinoa (Chenopodium quinoa Willd.) Varieties Grown in North-West Europe—Part I

The cultivation of quinoa has gained increasing interest in Europe. Different European varieties exist, but more research is required to understand the individual variety characteristics for end-use applications. The objective of this study is to evaluate the agronomic performance of 13 quinoa varieties under North-West European field conditions during three growing seasons (2017–2019). Furthermore, seeds were qualitatively characterized based on characteristics and composition. Yield differed among varieties and growing seasons (0.47–3.42 ton/ha), with lower yields obtained for late-maturing varieties. The saponin content varied from sweet to very bitter. The seeds contained high protein levels (12.1–18.8 g/100 g dry matter), whereas varieties had a similar essential amino acid profile. The main fatty acids were linoleic (53.0–59.8%), α-linolenic (4.7–8.2%), and oleic acid (15.5–22.7%), indicating a high degree of unsaturation. The clustering of varieties/years revealed subtle differences between growing seasons but also reflected the significant interaction effects of variety and year. Most varieties perform well under North-West European conditions, and their nutritional content is well within the values previously described for other cultivation areas. However, optimal yield and quality traits were not combined in one variety, illustrating the importance of breeding for adapted quinoa varieties.

Increased Tea Saponin Content Influences The Diversity and Function of Plantation Soil Microbiomes

Background Plant secondary metabolites (PSMs) can affect the structures and functions of soil microbiomes. However, the core bacteria associated with PSMs, and their corresponding functions have not been explored extensively. In this study, soil physicochemical properties, tea saponin contents, microbial community compositions, and microbial community functions of different-age Camellia oleifera plantation soils from representative regions were analyzed. We evaluated the effects of plantation age increase on PSM accumulation, and the subsequent consequences on the structures and functions of soil microbiomes. Results Plantation ages increase positively corresponded with accumulated tea saponin contents, with negative effects on soil physicochemical properties, and soil microbiome structures and functions. Older plantation soil microbiomes exhibited simpler structures, lower diversity, and relatively looser putative interactions based on network analysis. Clearly, the core functions of soil microbiomes transitioned to those associated with PSM metabolisms, while microbial pathways involved in cellulose degradation were inhibited. Degradation experiments further confirmed that older plantation soils exhibited the higher capacity on tea saponin degradation but poorer on furfural. Conclusions This study systematically explored the influences of PSMs on soil microbiomes via the investigation of key bacterial populations and their functional pathways. With the increase of planting years, increased tea saponin content simplified the soil microbiomes diversity, inhibited the degradation of organic matter, and enriched the genes related to the degradation of tea saponin. These findings significantly advance our understanding on PSMs-microbiome interactions and could provide fundamental and important data for sustainable management of Camellia plantations.

Evaluation of Solvent Extraction Process for Asparagus racemosus Root Extract through the Determination of its Phenolic Content and Antioxidant Activity Assay

This study is aimed to evaluate extraction capacity of different solvents through determining total phenolic content, total flavonoid content, total saponin content, and an antioxidant assay of different solvent extracts (toluene, dichloromethane, chloroform, ethyl acetate, ethanol, methanol, water, 60% aqueous methanol, 60% aqueous ethanol and 60% aqueous acetone) of Asparagus racemosus (A. racemosus) root. The 60% aqueous methanol shows the highest extracting yield, in contrast, toluene shows the lowest yield. Highest total phenolic content (220.8±0.74mg GAE/g), total flavonoid content (219.3±0.64mg QCE/g), total tannin content (108.4±0.88mg GAE/g) were found from acetone extract. The methanol extract showed the highest saponin content (579.4±2.85mg ESE/g). Antioxidant potential determines by using various in vitro methodologies such as DPPH, FRAP, and ABTS assay. The lowest IC50 value was found in acetone extract and thus it exhibited the highest antioxidant activity. The highest correlation was found between phenolic content and the antioxidant assay. It seems that phenolic contents are responsible for free radicle scavenging activity. From the observation, it concluded that acetone extract rich with polyphenolic content and methanol extract shows the highest amount of saponin content.

Analysis of Flavonoids and Saponins of Contents in the Ration of Sheep Added with Multinutrient Block with Different Level of Papaya Leaves Flour

This study aimed to examine the composition of flavonoids and saponins in sheep rations added with multi-nutrient blocks with different levels of papaya leaves (0%, 2%, 4%, and 6%). The research design used was a completely randomized design with 4 treatments and 3 replications. The treatment used was T0: sheep ration added MNB without papaya leaves flour, T1: sheep ration added MNB using 2% papaya leaves flour, T2: sheep ration added MNB using 4% papaya leaves flour, and T3: sheep ration added MNB using 6% papaya leaves flour. The parameters reviewed were flavonoids and saponins. The materials used were sheep ration (forage and concentrate), multi-nutrient blocks and papaya leaves flour. The method used is making complete rations, making MNB, and the analysis stage. The treatment used in the study was a complete ration, consisting of forage and concentrate added with multi-nutrient blocks with papaya leaf levels of 0%, 2%, 4%, and 6%. The results of the study were that sheep ration added MNB with different levels of papaya leaves flour did not show an increase in flavonoids and saponins. The highest flavonoids content was found at sheep ration added MNB using 4% papaya leaves flour while the highest saponin content was found at sheep ration added MNB using 6% papaya leaves flour.