Soil amendment with agro‐industrial byproducts: molecular‐chemical compositions and effects on soil biochemical activities and phosphorus fractions

Environmental pollution by agro‐industrial byproducts in developing countries can be alleviated by recycling into soils. However, little is known about their chemical composition and impact on soil fertility. Therefore, the objectives of the present study were (1) to characterize the molecular‐chemical composition of dry (COD) and wet (COW) coffee, sisal (SIS), barley malt of brewery (BEB), and sugarcane processing (FIC) byproducts, and filter cakes of linseed (LIC) and niger seed (NIC) and (2) to evaluate their effects on respiration, pH, enzyme activities, and P fractions of a tropical soil. The agro‐industrial byproducts significantly differed in their concentrations of plant nutrients and organic‐matter compositions. The highest proportions of lipids, phenols + lignin monomers, and alkylaromatics were observed in COD, N‐containing compounds in COW, sterols in FIC, peptides in LIC, suberin in SIS, and fatty acid in COW and FIC. The application of the byproducts at the rate of 40 kg P ha^–1 (1.1 to 13.2 g C [kg soil]^–1) significantly (p < 0.05) increased the rate and cumulative soil respiration, soil pH, acid phosphatase and urease activities, and labile inorganic P over the control treatment. Ranking the qualities of the agro‐industrial byproducts for soil amendment based on their composition and effects on soil properties revealed the order NIC > LIC > BEB > COW > SIS > FIC > COD.     

Characterization and quantitation of polyphenolic compounds in bark, kernel, leaves, and peel of mango (Mangifera indica L.)

The contents of secondary plant substances in solvent extracts of various byproducts (barks, kernels, peels, and old and young leaves) in a range of Brazilian mango cultivars were identified and quantitated. The results show that the profiles of secondary plant substances such as xanthone C-glycosides, gallotannins, and benzophenones in different byproducts vary greatly but are fairly consistent across cultivars. The free radical scavenging activity of the solvent extracts was evaluated using a high-performance liquid chromatography-based hypoxanthine/xanthine oxidase assay and revealed dose-dependent antioxidant capacity in all extracts. Four (mangiferin, penta- O-galloyl-glucoside gallic acid, and methyl gallate) of the major phenolic compounds detected were also evaluated in additional in vitro bioassay systems such as oxygen radical absorbance capacity, 2,2-diphenyl-1-picrylhydrazyl, and ferric reducing ability of plasma. Mangiferin in particular, detected at high concentrations in young leaves (Coite = 172 g/kg), in bark (Momika = 107 g/kg), and in old leaves (Itamaraka = 94 g/kg), shows an exceptionally strong antioxidant capacity.     

Upgrading of maatjes herring byproducts: production of crude fish oil

Fish oil has been extracted from byproducts of the maatjes (salted) herring production using a pilot plant consisting of a mincer, heat exchanger, and three-phase decanter. The crude herring oil obtained had an initial peroxide value (PV), anisidine value (AV) and free fatty acids (FFA) level of only 3 mequiv of peroxide/kg of lipid, 8.9, and 2.9%, respectively. 5,8,11,14,17-Eicosapentaenoic acid (EPA) and 4,7,10,13,16,19-docosahexaenoic acid (DHA) were present in considerable amounts (99 and 91 g/kg, respectively). During storage of the oil, no photooxidation could be detected. Storage at room temperature led to significant autoxidation over time, apparent from primary and tertiary oxidation products, measured by a decrease of hydroperoxides and an increase of fluorescent compounds (FC). Storage at 50 degrees C resulted in significant increases in secondary (AV) and tertiary oxidation (FC) products. At all storage conditions, the FFA contents remained low (<3%) and the alpha-tocopherol content remained constant. These results open the possibility for fish oil production of good quality using salted herring byproducts.     

Artichoke (Cynara scolymus L.) byproducts as a potential source of health-promoting antioxidant phenolics

The present study reports a fast, economical, and feasible way to extract antioxidant phenolics from artichoke byproducts: raw artichoke (RA), blanched (thermally treated) artichoke (BA), and artichoke blanching waters (ABW). These byproducts represent a huge amount of discarded material in some industries. Two protocols, with possible industrial applicability, based on both methanol and water extractions were used. Phenolic contents (expressed as caffeic acid derivatives) (grams per 100 g of dry extract) were 15.4 and 9.9 for RA when extracted with methanol and water, respectively; 24.3 and 10.3 for BA when extracted with methanol and water, respectively; and finally, 11.3 g of phenolics/100 mL of ABW. Therefore, methanol extracts yielded more phenolics than water extracts, especially when BA byproducts were used. The higher amount of phenolics in BA could be due to the inactivation of polyphenol oxidase (PPO) at the industrial scale (due to blanching process), avoiding PPO-catalyzed oxidation of these phenolics, a phenomenon that could occur in RA byproducts. Artichoke extracts from industrial byproducts showed a high free radical scavenging activity (versus both DPPH* and ABTS*+ radicals) as well as capacity to inhibit lipid peroxidation (ferric thiocyanate method). According to these results, the use of artichoke extracts from industrial byproducts as possible ingredients to functionalize foodstuffs (to decrease lipid peroxidation and to increase health-promoting properties) is suggested.     

脱硫废弃物施用对盆栽油葵碱化土壤微生物多样性的影响

在宁夏平罗西大滩前进农场,利用盆栽试验以油葵为指示植物设置了脱硫废弃物5个不同施用量处理改良碱化土壤,采用Biolog Eco-plate技术对土壤微生物群落功能多样性进行了分析.结果表明:脱硫废弃物施用处理都能够降低土壤pH值0.06～0.29个单位;降低土壤全盐含量0.72～1.35 g/kg;脱硫废弃物施用能够明...     

Chemical and sensory evaluation of crude oil extracted from herring byproducts from different processing operations

Fish oils extracted from marinated herring (frozen and unfrozen) byproducts and maatjes herring byproducts were evaluated on their chemical and sensory properties. The obtained crude oils had very low content of copper (<0.1 mg/kg oil), and iron values were 0.8, 0.1, and 0.03 mg/kg oil, respectively, for oil from maatjes and frozen and fresh byproducts. For the maatjes oil, a much lower value was found for alpha-tocopherol compared to the other oils. Storage stability results showed that the oils behave differently. Secondary oxidation products were measured for fresh oil, while for the maatjes and frozen byproducts' oil, tertiary oxidation products were detected. Over storage time, the maatjes and frozen byproducts' oils became more intense in odor, correlating positively at the end with sensory attributes of train-oil, acidic, marine and fishy. The best correlation between sensory and chemical analyses was found for FFA and fishy off-odor (r = 0.781).     

Structural carbohydrate differences and potential source of dietary fiber of onion (Allium cepa L.) tissues.

Onion tissues of three varieties were evaluated for dietary fiber (DF) composition. Insoluble (IDF) and soluble (SDF) dietary fibers were subjected to acid hydrolysis, and the resultant neutral sugars, uronic acids, and Klason lignin were quantified. Brown skin exhibited the highest total dietary fiber (TDF) content (65.8%) on a dry matter basis, followed by top (48.5%) and bottom (38.6%), IDF being the main fraction found. The SDF:IDF ratio decreased from inner to outer tissues. Brown skin and outer leaves byproducts appear to be the most suitable sources of DF that might be used in food product supplementation. The chemical composition reveals that cellulose and pectic polysaccharides were the main components of onion DF in all tissues, although differences between them were noticed. An increase in the uronic acids/neutral sugars ratio from inner to outer tissues was found, suggesting that the galactan side chain shows a DF solubilization role.     

Lettuce and chicory byproducts as a source of antioxidant phenolic extracts

A process to obtain enriched antioxidant phenolic extracts from lettuce (baby, romaine, and iceberg cultivars) and chichory byproducts as a way to valorize these byproducts was developed. Two extraction protocols using water and methanol as solvent were used. Amberlite XAD-2 nonionic polymeric resin was used to purify the extracts. The extraction yield, phenolic content, and phenolic yield were evaluated as well as the antioxidant capacity of the extracts (DPPH, ABTS, and FRAP assays). Baby and romaine lettuce byproducts showed the highest water extract yields [27 and 26 g of freeze-dried extracts/kg of byproduct fresh weight (fw), respectively], whereas baby and iceberg lettuce showed highest methanol extract yields (31 and 23 g of freeze-dried extracts/kg of byproduct fw, respectively). Methanol extraction yielded a raw extract with a high phenolic content, the baby and chicory extracts being the richest with approximately 50 mg of phenolics/g of freeze-dried extract. Regarding the purified extracts, water extraction yielded a higher phenolic content, baby and chicory being also the highest with mean values of approximately 190 and 300 mg of phenolics/g of freeze-dried extract, respectively. Both raw and purified extracts from baby and chicory showed the higher antioxidant contents (DPPH, ABTS, and FRAP assays). The antioxidant capacity was linearly correlated with the phenolic content. The results obtained indicate that lettuce byproducts could be, from the industrial point of view, an interesting and cheap source of antioxidant phenolic extracts to funcionalize foodstuffs.     

Demonstration of pectic polysaccharides in cork cell wall from Quercus suber L

Scanning electron microscopy (SEM) and chemical analysis were used to observe the cell wall changes that occur in cork with "mancha amarela", when compared to a standard cork. To mimic the microbial attack exhibited in cork with mancha amarela, the standard cork was treated enzymatically with commercial pectinase and hemicellulase preparations. The tissues treated with pectinase were comparable with those attacked with mancha amarela. Both were composed by deformed and wrinkly cells and exhibited cell wall separation at the middle lamella level, which suggests solubilization/removal of the pectic polysaccharides. The cork cell wall material, prepared as alcohol-insoluble residue, was fractionated by hot water (Pect(H)()2(O)) and hot dilute acid (Pect(acid)). The relatively large amount of hexuronic acid and the occurrence of Ara in the SPect(H)()2(O) and SPect(acid) allow to confirm, as far as we know, for the first time the presence of pectic polysaccharides in the cell walls of cork from Quercus suber L. They accounted for ca. 1.5% of the cork and may consist of polymers with long side chains of arabinosyl residues. These polymers have to be taken into account in any realistic model of the cork cell wall. Cork with mancha amarela contained a smaller amount of pectic polysaccharides (ca. 0.5%), which confirms that the cellular separation observed by SEM is related to the degradation/removal of the middle lamella pectic polysaccharides.     

Phenolic acids in berries, fruits, and beverages

The contents of soluble and total phenolic acids were analyzed in samples of 29 berries and berry products, 24 fruits and fruit peels, and 12 beverages. Variation of phenolic acids in berries was also studied. Soluble phenolic acids were extracted with methanolic acetic acid, and a tentative quantification was performed by high-performance liquid chromatography (HPLC). The total phenolic acid content was determined by HPLC after alkaline and acid hydrolyses. The content of total phenolic acids as aglycones in the above samples varied from 0 (pear cider) to 103 mg/100 g fresh weight (rowanberry). Besides rowanberry, the best phenolic acid sources among berries were chokeberry (96 mg/100 g), blueberry (85 mg/100 g), sweet rowanberry (75 mg/100 g), and saskatoon berry (59 mg/100 g). Among fruits, the highest contents (28 mg/100 g) were determined in dark plum, cherry, and one apple variety (Valkea Kuulas). Coffee (97 mg/100 g) as well as green and black teas (30-36 mg/100 g) were the best sources among beverages. Caffeic acid dominated in all of these samples except in tea brews. Variation in the phenolic acid contents of the berries was either small or moderate.     

Effect of heat treatment on nutritional quality of germinated legume seeds

The effect of heat treatment of germinated soybean, lupin, and black bean on chemical composition and protein utilization in rats was evaluated. Heat treatment caused complete inactivation of trypsin inhibitors whereas it did not affect phytic acid levels. Proximate components, minerals, and amino acids did not change, but low molecular weight sugars were affected by heat treatment differently for each germinated legume. The sugar digestibility ratio (total digestible sugars/total nondigestible sugars) in germinated black beans doubled after heat treatment. True protein digestibility (TD) increased with heat treatment only in germinated soybean. Net protein utilization was markedly improved (20%) with heat treatment in germinated soybean and lupin. Utilizable protein of heat-treated germinated legumes was 289, 236, and 132 g/kg of legume dry weight for soybean, lupin, and black bean, respectively. Supplementation with methionine did not alter TD but improved all other indices of protein utilization in the germinated legumes, particularly in black bean. All three germinated legumes become equivalent in protein quality when heating and supplementation with methionine are combined with germination. The use of germinated heat-treated soybean, lupin, and black bean on their own and/or as food ingredients is nutritionally advantageous due to the low content of nondigestible oligosaccharides and the high protein utilization.     

Phytase and acid phosphatase activities in plant feedstuffs

A total of 183 samples representing 24 feedstuffs were analyzed for total phosphorus, phytate phosphorus content, phytase (Phy), and acid phosphatase (AcPh) activities with the objective to predict the capacity to hydrolyze phytic acid and to contribute to formulating environmentally adequate diets for monogastric animals. Of the cereals and cereal byproducts analyzed, only rye (5147 U kg(-)(1); 21 955 U g(-)(1)), wheat (1637 U kg(-)(1); 10 252 U g(-)(1)), rye bran (7339 U kg(-)(1); 56 722 U g(-)(1)), and wheat bran (4624 U kg(-)(1); 14 106 U g(-)(1)) were rich in Phy and AcPh activities. Legume seeds and oilseeds contained negligible Phy activity and a moderate amount of AcPh activity, except for kidney bean (33 433 U g(-)(1)) and full-fat linseed meal (13 263 U g(-)(1)). On the other hand, a significant linear regression between phytate phosphorus (y) and total phosphorus (x) was observed in cereal byproducts (R(2) = 0. 95; y = 0.8458x - 0.0367; P < 0.001) and oil seeds (R(2) = 0.95; y = 0.945x - 0.20; P < 0.001). Phy and AcPh were positively correlated with respect to phytate phosphorus in cereals, cereal byproducts, and other byproducts and negatively correlated in legume seeds and oilseeds. Except for cereals, the highest correlation between enzyme activities and phytate phosphorus was found for phytase. It is not possible to predict Phy and AcPh activities from phytate phosphorus content by linear and quadratic regressions. Finally, only highly significant and positive correlation was found between Phy and AcPh activities for cereals, cereal byproducts, and oilseeds.     

长期化肥有机替代对黑土颜色及腐殖物质的影响

基于30年长期定位试验,通过测定黑土光谱反射率和不同腐殖质组分含量,探究了不同施肥对黑土土壤腐殖质含量、土壤颜色及二者之间的关系。试验设置5个处理:(1)休耕(Fallow);(2)不施肥处理(CK);(3)单施化肥(NPK);(4)有机肥部分替代化肥(NPKM);(5)秸秆部分替代化肥处理(NPKS)。结果表明:与NPK处理相比,Fallow、NPKS、NPKM分别显著提高49.7%,74.3%,27.0%的土壤有机碳含量(p<0.05)。NPKM处理中胡敏酸(HA)含量最高为3.9 g/kg,随后依次为CK、NPKS、NPK、Fallow。NPKM、NPKS和Fallow处理中土壤富里酸(FA)含量为2.2~2.3 g/kg,显著高于NPK和CK。NPKM处理中胡敏素(HM)含量为18.6 g/kg,显著高于其他处理(p<0.05)。不同处理间土壤光谱反射率由高到低依次为NPK>Fallow、CK>NPKS>NPKM,与CK处理相比,NPK土壤光谱反射率在平均提高6.5%,NPKS和NPKM则分别降低11.1%和15.1%。根据线性相关分析结果,黑土土壤光谱反射率与土壤HAHM均呈显著负相关关系(p<0.01),相关系数(r)分别为-0.858,-0.681。综合上述结果,长期有机物料投入可以显著提高黑土腐殖物质含量,降低黑土光谱反射率,使黑土颜色加深,而长期化肥施入则使黑土光谱反射率提高,出现"褪色"现象,有机粪肥在黑土中对土壤有机质和腐殖质含量的提升效果优于秸秆。     

Antiproliferative terpenoids from almond hulls (Prunus dulcis): identification and structure-activity relationships

Bioassay-guided fractionation of the EtOAc crude extract from Sicilian almond hulls, a waste material from Prunus dulcis crop, allowed identification of 10 constituents, isolated as pure compounds (1-5, 7, and 10) or unseparable mixtures (5 + 6 and 8 + 9). All compounds were subjected to spectroscopic analysis and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide bioassay on MCF-7 human breast cancer cells. In addition to the main components oleanolic (1), ursolic (2), and betulinic (3) acids, the 2-hydroxy analogues alphitolic (4), corosolic (5), and maslinic (6) acids, as well as the related aldehydes, namely, betulinic (7), oleanolic (8), and ursolic (9), were identified. From a more polar fraction, the beta-sitosterol 3-O-glucoside (10) was also identified. A sample of commercially available betulin (11) was also included in bioassays as further support to a structure-activity relationship study. Betulinic acid showed antiproliferative activity toward MCF-7 cells (GI50 = 0.27 microM), higher than the anticancer drug 5-fluorouracil.     

High-amylose corn exhibits better antioxidant activity than typical and waxy genotypes

The consumption of fruits, vegetables, and whole grains rich in antioxidative phytochemicals is associated with a reduced risk of chronic diseases such as cancer, coronary heart disease, diabetes, Alzheimer's disease, cataract, and aged-related functional decline. For example, phenolic acids are among the main antioxidative phytochemicals in grains that have been shown to be beneficial to human health. Corn (Zea mays L.) is a major staple food in several parts of the world; thus, the antioxidant activity of several corn types was evaluated. The 2,2-Diphenyl-1-picryhydrazyl free radical (DPPH*) scavenging activity, total phenolic content (TPC), antioxidant capacity of lipid-soluble substances (ACL), oxygen radical absorbance capacity (ORAC), and phenolic acid compositions of typical and mutant genotypes (typical-1, waxy, typical-2, and high-amylose) were investigated. The DPPH* scavenging activity at 60 min was 34.39-44.51% in methanol extracts and 60.41-67.26% in HCl/methanol (1/99, v/v) extracts of corn. The DPPH* scavenging activity of alkaline hydrolysates of corn ranged from 48.63 to 64.85%. The TPC ranged from 0.67 to 1.02 g and from 0.91 to 2.15 g of ferulic acid equiv/kg of corn in methanol and HCl/methanol extracts, respectively. The TPC of alkaline hydrolysates ranged from 2.74 to 6.27 g of ferulic acid equiv/kg of corn. The ACL values were 0.41-0.80 and 0.84-1.59 g of Trolox equiv/kg of corn in methanol and HCl/methanol extracts, respectively. The ORAC values were 10.57-12.47 and 18.76-24.92 g of Trolox equiv/kg of corn in methanol and HCl/methanol extracts, respectively. ORAC values of alkaline hydrolysates ranged from 42.85 to 68.31 g of Trolox equiv/kg of corn. The composition of phenolic acids in alkaline hydrolysates of corn was p-hydroxybenzoic acid (5.08-10.6 mg/kg), vanillic acid (3.25-14.71 mg/kg), caffeic acid (2.32-25.73 mg/kg), syringic acid (12.37-24.48 mg/kg), p-coumaric acid (97.87-211.03 mg/kg), ferulic acid (1552.48-2969.10 mg/kg), and o-coumaric acid (126.53-575.87 mg/kg). Levels of DPPH* scavenging activity, TPC, ACL, and ORAC in HCl/methanol extracts were obviously higher than those present in methanol extracts. There was no significant loss of antioxidant capacity when corn was dried at relatively high temperatures (65 and 93 degrees C) postharvest as compared to drying at ambient temperatures (27 degrees C). Alkaline hydrolysates showed very high TPC, ACL, and ORAC values when compared to methanol and HCl/methanol extracts. High-amylose corn had a better antioxidant capacity than did typical (nonmutant) corn genotypes.     

新疆典型草原土壤腐殖酸组分的变化规律

以新疆典型草原黑钙土、栗钙土和棕漠土为对象,研究了3种土壤不同土层腐殖质矿物复合体组分及其垂直分布规律。结果表明:13种典型草原土壤腐殖质总碳量的顺序为黑钙土(35、46g/kg)、栗钙土(31.30g/kg)和棕漠土(0.68g/kg);23种草原土壤都是以胡敏素(HM)含量最高,黑钙土、栗钙土和棕漠土的含量分别为68.17%、65.47%和42.81%;3按照腐殖酸类型分析,黑钙土和栗钙土是以胡敏酸(HA)为主的富啡酸(FA)-胡敏酸(HA)型,CH/CF＞1;而棕漠土则相反,是胡敏酸-富啡酸型,CH/CF＜1;4黑钙土、栗钙土和棕漠土腐殖质组分中游离R₂O₃结合的胡敏酸分别为6.85%、5.65%和1.65%,而富啡酸分别为0.53%、0.84%和4.91%;5在3种草原土壤中,游离腐殖酸从0~20cm到40~60cm的垂直变化规律分别为:黑钙土中游离胡敏酸和富啡酸分别从5.74和2.33g/kg降到2.70和0.89g/kg;栗钙土中游离胡敏酸和富啡酸分别从1.88和1.03g/kg降到0.59和0.75g/kg;棕漠土中游离胡敏酸和富啡酸分别由2.10和2.90g/kg降到1.92和0.67g/kg。     

Separation and HPLC-MS identification of phenolic antioxidants from agricultural residues: almond hulls and grape pomace

Almond hulls and grape pomace are residues abundantly generated by agricultural industries, which could be processed to obtain bioactive products. To this purpose, crude ethanol extracts from both agricultural byproducts were attained and subsequently fractionated in order to obtain an organic/water fraction (FOW). Extracts and fractions were analyzed for antioxidant power and their phenolic components tentatively identified by HPLC-MS. Chromatographic peaks of almond hull extracts showed the occurrence of hydroxybenzoic and cinnamic acid derivatives, with minor presence of flavan-3-ols (ECG, EGCG), whereas the FOW fraction offered the additional presence of epicatechin (EC) and glycosylated flavonols. In the composition for extracts of white and red grape pomace several of these compounds were also detected but basically consisted of glycosylated flavonols (quercetin, kaempferol). As a difference between both grape pomaces, myricetin glycosyde was found in that from the red variety, whereas flavan-3-ols (EC, afzelechin) were only identified in white pomace. When their FOW fractions were analyzed, gallic acid and some hydroxybenzoic acids were additionally detected. Antioxidant activity was assessed by DPPH and TBARS assays. Almond hulls showed inhibition percentages lower than 50% in both assays, while the inhibition percentage ranged from 80% to 90% in pomace extracts. Red grape pomace extract was the most efficient antioxidant, with an EC50 value of 0.91 g/L for TBARS and 0.20 g/L for DPPH. Even appearing as two quite different vegetal matrixes, the composition of phenolics in grape pomace and almond hulls is quite similar, the main difference being the major occurrence of flavonols in grape pomace. This fact could presumably explain the lower antiradical activity of hull extracts.     

烤烟根际土壤微生物对根系酚酸类物质的响应

【目的】烟草连作导致化感物质累积,探索化感物质中主要的酚酸类物质对根际土壤微生物的影响,可为克服烟草连作障碍提供理论依据。【方法】采用盆栽试验方法,将前期分离、鉴定出的烟草根系分泌物中主要酚酸类物质苯甲酸和3-苯丙酸接种到土壤中,模拟烟草多年连作土壤。试验设4个处理:对照(T0),向土壤中加入等量灭菌去离子水;添加苯甲酸3μg/kg土(T1);3-苯丙酸8μg/kg土(T2);同时添加苯甲酸3μg/kg土和3-苯丙酸8μg/kg土(T3),每处理5次重复。以MiSeq测序平台对根际土壤微生物进行高通量测序,探索其对根际土壤微生物的影响,同时采用荧光定量PCR法检测土壤中的茄科劳尔氏菌、短短芽孢杆菌、固氮菌、无机磷细菌、硅酸盐细菌等功能微生物及细菌和真菌的数量变化。【结果】T 1、 T 2处理土壤细菌OTUs(Operational Taxonomic Units)数目分别比对照T0降低了21.5%和17.0%,T3处理OTU数量低于T1和T2处理;T2处理土壤中优势微生物种群增多,结构平衡性降低,门上分类构成和微生物群落构成显著不同于对照。主成分分析与聚类分析显示,T2或T3处理土壤微生物聚类关系较近,都与T0处理较远;T3处理土壤中病原菌数量显著提高,拮抗菌、固氮菌、无机磷细菌、硅酸盐细菌、细菌和真菌数量显著减少,且减少幅度大于T1、T2处理。【结论】根系分泌物中主要酚酸类物质苯甲酸和3-苯丙酸均能明显改变根际土壤微生物区系,降低土壤微生群落多样性,显著增加有害微生物数量的同时大大降低有益微生物数量。两种酚类同时存在的危害效果远大于单一酚类。     

Contents of vitamins, mineral elements, and some phenolic compounds in cultivated mushrooms

The aim of the study was to determine the contents of mineral elements (Ca, K, Mg, Na, P, Cu, Fe, Mn, Cd, Pb, and Se), vitamins (B(1), B(2), B(12), C, D, folates, and niacin), and certain phenolic compounds (flavonoids, lignans, and phenolic acids) in the cultivated mushrooms Agaricus bisporus/white, Agaricus bisporus/brown, Lentinus edodes, and Pleurotus ostreatus. Selenium, toxic heavy metals (Cd, Pb), and other mineral elements were analyzed by ETAAS, ICP-MS, and ICP methods, respectively; vitamins were detected by microbiological methods (folates, niacin, and vitamin B(12)) or HPLC methods (other vitamins), and phenolic compounds were analyzed by HPLC (flavonoids) or GC--MS methods (lignans and phenolic acids). Cultivated mushrooms were found to be good sources of vitamin B(2), niacin, and folates, with contents varying in the ranges 1.8--5.1, 31--65, and 0.30--0.64 mg/100 g dry weight (dw), respectively. Compared with vegetables, mushrooms proved to be a good source of many mineral elements, e.g., the contents of K, P, Zn, and Cu varied in the ranges 26.7--47.3 g/kg, 8.7--13.9 g/kg, 47--92 mg/kg, and 5.2--35 mg/kg dw, respectively. A. bisporus/brown contained large amounts of Se (3.2 mg/kg dw) and the levels of Cd were quite high in L. edodes (1.2 mg/kg dw). No flavonoids or lignans were found in the mushrooms analyzed. In addition, the phenolic acid contents were very low.     

Production of L-lactic acid and oligomeric compounds from apple pomace by simultaneous saccharification and fermentation: a response surface methodology assessment

The potential of apple pomace for lactic acid production by simultaneous saccharification and fermentation (SSF) was evaluated. The effects of the cellulase to solid ratio (CSR), the liquor to solid ratio (LSR), and the beta-glucosidase to cellulase ratio (BCR) on the kinetics of lactic acid generation were assessed, and a set of mathematical models was developed to reproduce and predict the lactic acid concentration of fermentation broths. Operating at low cellulase and cellobiase charges (1 FPU/g and 0.25 IU/FPU, respectively) and short reaction times (10 h), SSF media containing 27.8 g of lactic acid/L were obtained with a volumetric productivity of 2.78 g/Lh. Material balances showed that the SSF processing of 100 kg of dry apple pomace results in the production of 36.6 kg of lactic acid, 18.3 kg of oligomeric carbohydrates (which can be used as ingredients for functional foods), 8.4 kg of microbial biomass, and 8 kg uronic acids.