Free Acid Content Research Articles

Beekeeping Practices and Physicochemical Properties of Honey Produced in Maun, Botswana

Beekeeping sector plays a major role in rural socio-economic development and environmental conservation. Maun has been identified as one of the excellent potential areas for honeybee production in Botswana because of its suitable agroecological condition for beekeeping. Maun village is located in north-western Botswana and tourism is the main economic activity in the area. It is situated at the gateway for tourists visiting the Okavango Delta and Moremi Game Reserve. The study was conducted to assess beekeeping practices and determine the physicochemical properties of honey produced in Maun village. Honeybee production practices were assessed by conducting questionnaire survey. Three honey samples were obtained each from backyard hives and the forest and analysed for their physicochemical properties following standard procedures. Honey samples collected from backyard hives had an average moisture (%), pH, free acidity (meq/kg), total ash (%), reducing sugars (%), sucrose (%) and Hydroxymethylfurfural (HMF) (mg/kg) contents of 18.03±0.15, 4.12±0.02, 21.6±0.10, 0.14±0.01, 71.27±0.13, 1.63±0.02 and 17.67±0.21, respectively. The corresponding values for honey samples collected from the forest were 17.43±0.21, 6.45±0.17, 13.17±0.06, 0.27±0.02, 60.38±0.16, 0.84±0.04 and 20.63±0.55, respectively. Significant differences (p＜0.05) were observed between backyard and forest honey samples for all the parameters considered. The pH, total ash and HMF contents of forest honey samples were significantly higher (p＜0.05) than the corresponding values for backyard honey. On the other hand, the moisture, free acidity, reducing sugars and sucrose contents of backyard honey samples were significantly higher (p＜0.05) than the corresponding values for forest honey. In Maun area, honey is mainly produced in the backyards of farmers using modern hives although some honey is collected from the forest. The dominant vegetation in the area that are used as bee forage include herbs such as rosemary (Salvia rosmarinus), lavender (Lavendula angustifolia), fennel (Foeniculum vulgare) and peppermint (Mentha piperita), strawberry plant (Fragaria ananassa), watermelon (Citrullus lanatus) and marula tree (Sclerocarya birrea). Honey is mostly harvested in December, and it is used for acne and flu remedy, colds, and as a sweetener. The major challenges of beekeeping in the area were reported to be pests such as wax moth, ants and yellow jackets; use of pesticides and harsh weather conditions. In conclusion, honey produced in Maun area is of good quality. Most of the physicochemical parameters of both honey types analysed in the present study were within the limits of international standards for honey.

The physicochemical analysis and health benefits of fresh and branded honey produced in delta state, Nigeria

This research is aimed to investigate and evaluate the physicochemical characteristic of different honey produced in Delta State, Nigeria, to confirm its economical and nutritional quality in comparison with the international standard. The quality of fresh and branded honey samples produced in Delta State was assessed using physicochemical and mineral analysis. Eight fresh honey (FHs) samples and eight branded honey (BHs) samples were collected from the Autonomous Province of Delta State, Nigeria. The tested parameters were pH, free acidity, electrical conductivity, color intensity, moisture, ash, proline, diastase, HMF, invertase, glucose, fructose, sucrose, lipid and mineral content. A qualitative test (Fiehe, Lund and Lugol) was performed to test the purity of honey. Both honey samples displayed good physicochemical properties. The concentration level of sugars was higher in the branded honey in comparison to fresh honey samples. The physicochemical parameters of fresh and branded honey were in concordance with the international standard.

Dynamics of Changes in pH and the Contents of Free Sugars, Organic Acids and LAB in Button Mushrooms during Controlled Lactic Fermentation.

The aim of the study was to assess changes in the basic quality parameters induced by controlled lactic fermentation of fruiting bodies of the button mushroom (Agaricus bisporus). Lactiplantibacillus plantarum 299v with documented probiotic properties and L. plantarum EK3, i.e., an isolate obtained from spontaneously fermented button mushrooms, were used as starter strains. The fruiting bodies of fresh, blanched, and fermented mushrooms were analyzed at different stages of the lactic fermentation process. The content of free sugars (high-performance liquid chromatography with charged aerosol detector method; HPLC-CAD) and organic acids (high-performance liquid chromatography with diode array detector method; HPLC-DAD) was determined both in the mushroom fruiting bodies and in the brine. Five free sugars (ribose, trehalose, sucrose, glucose, and fructose), mannitol, and six organic acids (lactic, malic, succinic, citric, acetic, and fumaric acids) were detected in the samples. Lactic acid dominated in the final products. The starter cultures exhibited varying degrees of utilization of available mushroom sugars and sucrose used as an additional substrate. Sucrose was utilized at a higher rate and in greater amounts by the L. plantarum EK3 isolate. This starter culture was characterized by a significantly higher final amount of produced lactic acid, a lower pH value, and higher numbers of LAB (lactic acid bacteria). These important quality parameters largely determine the stability of fermented products. Based on the analysis results and the high scores in the organoleptic evaluation of the fermented mushrooms, the L. plantarum EK3 isolate can be recommended as an appropriate starter culture for lactic fermentation of mushroom fruiting bodies.

Alteration in phytochemicals from sweet maize in response to domestic cooking and frozen storage

Sweet maize has worldwide importance due to its high nutritional value and health benefits. In order to provide valuable health-related information to consumers, the phytochemicals profile of raw sweet maize kernels and those exposed to different treatments (cooking, frozen storage before cooking, sucrose addition during cooking, and blanching) was examined herein. Thus, carotenoids, tocopherols and free phenolic acids content was determined by liquid chromatography, while the content of water soluble sugars was analyzed by anion exchange chromatography. In response to immediate cooking, as well as, to blanching prior to shorter frozen storage and cooking afterwards, all hybrids exhibited a significant decrease in carotenoids, and a significant increase in concentration of tocopherols, fructose, glucose, protocatechuic, ferulic and p-coumaric acids, in comparison to the fresh samples. However, treatments with blanching prior to longer frozen storage and cooking afterwards, contributed only to increased tocopherols content. Distinct grouping of processed samples in comparison to their corresponding control samples, revealed the existence of unique linkage between changes in phytochemicals content upon treatment in a hybrid-dependent manner. Combined blanching prior to shorter frozen storage with sucrose addition during cooking is highly recommended as a potent tool for phytochemicals enhancement.

MAMP-elicited changes in amino acid transport activity contribute to restricting bacterial growth.

Plants live under the constant challenge of microbes that probe the environment in search of potential hosts. Plant cells perceive microbe-associated molecular patterns (MAMPs) from incoming microbes and activate defense responses that suppress attempted infections. Despite the substantial progress made in understanding MAMP-triggered signaling pathways, the downstream mechanisms that suppress bacterial growth and disease remain poorly understood. Here, we uncover how MAMP perception in Arabidopsis (Arabidopsis thaliana) elicits dynamic changes in extracellular concentrations of free L-amino acids (AA). Within the first 3 h of MAMP perception, a fast and transient inhibition of AA uptake produces a transient increase in extracellular AA concentrations. Within 4 and 12 h of MAMP perception, a sustained enhanced uptake activity decreases the extracellular concentrations of AA. Gene expression analysis showed that salicylic acid-mediated signaling contributes to inducing the expression of AA/H+ symporters responsible for the MAMP-induced enhanced uptake. A screening of loss-of-function mutants identified the AA/H+ symporter lysin/histidine transporter-1 as an important contributor to MAMP-induced enhanced uptake of AA. Infection assays in lht1-1 seedlings revealed that high concentrations of extracellular AA promote bacterial growth in the absence of induced defense elicitation but contribute to suppressing bacterial growth upon MAMP perception. Overall, the data presented in this study reveal a mechanistic connection between MAMP-induced plant defense and suppression of bacterial growth through the modulation of AA transport activity.

Antioxidant and bioaccessibility characteristics of functional fruit and vegetable honeys produced by innovative method

The functional fruit and vegetable honeys were produced by the natural bee feeding method with pomegranate, orange and black carrot concentrates. The natural enrichment method did not cause any negative effects on the quality criteria questioned in the standards such as moisture, pH, free acidity and HMF (Hydroxymethylfurfuraldehyde) content and the quality of the functional honeys obtained was high. Parallel to TPC contents, the antioxidant values of the honeys were increased 5.00–31.50, 16.09–53.96 and 21.18–39.72% by enrichment of orange, pomegranate, and black carrot concentrates. Gallic acid in pomegranate honey (14.52%) and chlorogenic acid in black carrot honey (27.01%) were determined as antioxidant components increased by enrichment. The enrichment process also led to an increase in the bioaccessibility characteristics. The increased antioxidant activity of functional honeys (DPPH) was verified by a high negative correlation value (R = −0.9103) and decreasing IC50 ratios in the opposite direction.

Micro-analysis of nitrous oxide accumulation in denitrification under acidic conditions: The role of pH and free nitrous acid

Nitrous oxide (N2O), as an energy gas, is of increasing interest for its recovery from wastewater treatment. Acidic pH is one of the important factors affecting N2O accumulation during denitrification; however, its generation mechanism still needs further clarification. In this study, the production efficiency of N2O increased from 1.0 to 65.0% with the decrease in pH from 6.5 to 4.5 during nitrate-based denitrification performed in batch tests, which was accompanied by an increase in the nitrite accumulation. To further explore the mechanism, the net volumetric reaction rates of N2O within denitrified sludge aggregates were quantified by application of a microelectrode. When using N2O as a nitrogen source, the consumption rate of N2O was negatively correlated with both the hydrogen ion and free nitrous acid (FNA) concentrations. The inhibition of nitrous oxide reductase (NOS) activity in the absence of FNA demonstrates that hydrogen ion is the true inhibitor. When using NO as nitrogen source, the net volumetric production rates of N2O increased with decreasing pH, and they were higher in the presence of FNA compared to those in the absence of FNA, revealing that the increase in nitrite substrate promotes N2O production. Overall, the inhibition of NOS activity by hydrogen ions and FNA and the increase of substrate from nitrite accumulation are the main reasons for N2O enrichment under a low-pH condition.

Co‐fermentation metabolism characteristics of apple vinegar with Acetobacter pasteurianus and Lactobacillus plantarum

In this study, the growth and metabolic characteristics of Acetobacter pasteurianus and Lactobacillus plantarum used in the co-fermentation of apple vinegar were investigated. The results revealed that L. plantarum had little effect on the growth of A. pasteurianus during the co-fermentation process. The carbon sources used by L. plantarum and A. pasteurianus for growth were glucose and ethanol, respectively. Free amino acids, organic acids, and acetoin were analyzed using an amino acid analyzer, high-performance liquid chromatography, and gas chromatography, respectively. The results indicated that L. plantarum contributed to the accumulation of free amino acids during co-fermentation. Lactic acid, a key flavor substance, was accumulated mainly by L. plantarum during co-fermentation and was partly transformed into acetoin by A. pasteurianus. The acetoin content was 0.77 mg/ml, which is about twice that observed during pure fermentation with A. pasteurianus. Therefore, L. plantarum can improve the quality of apple vinegar during co-fermentation. Novelty impact statement L. plantarum had little effect on A. pasteurianus growth during co-fermentation of apple vinegar. The free amino acid and organic acid content in apple vinegar increased considerably because of the growth and metabolism of L. plantarum. The metabolites from L. plantarum could also be used by A. pasteurianus to improve the production of flavor substances during co-fermentation.

ВЛИЯНИЕ ПРОДОЛЖИТЕЛЬНОСТИ СВЕТОДИОДНОГО ОСВЕЩЕНИЯ НА БИОХИМИЧЕСКИЙ СОСТАВ МИКРОЗЕЛЕНИ ГОРОХА ОВОЩНОГО

The results of a comparative study of the effect of the duration of LED lighting are presented (8, 10, 12, 14, 16 hour) on 13 characteristics of the biochemical composition of vegetable peas microgreens (Pavlusha variety) - the content of dry, tannic and pectin substances, free organic, ascorbic and hydroxycinnamic acids, soluble sugars, total protein and albumins, the main groups of bioflavonoids and the indicator of the sugar acid index. The dry matter content in the studied samples was 9.3-11.8 %, the content of free organic, ascorbic and hydroxycinnamic acids in the dry mass was 4.35-8.46 %, 359.8-487.8 mg/100 g and 1465.1-1956.0 mg/100 g, respectively. The content of soluble sugars was from 8.8 to 13.2 % with significant variant differences in the indicator of the sugar acid index, which varied in the range of 1.04-3.03. At the same time, the parameters of the accumulation of pectin substances were 3.884.54 %, the content of tannins - 1.23-1.92 %. The almost complete absence of anthocyanin pigments in the pea microgreens was found, the content of flavonols varied in the range of 1711.7-2189.2 mg/100 g, and catechins - 376.7-483.0 mg/100 g. At the same time, a high content of proteins and their valuable part - soluble proteins (albumins), which varied in mg/g of dry weight in the ranges of 412.3-443.4 and 8.38-18.0, was found in the microgreens. The considerable width of the ranges of variation of the biochemical characteristics of the micro-green peas testified to their significant dependence on the duration of LED lighting, which was ambiguous. The least significant changes in the biochemical composition of peas microgreens relative to the control (12 hours duration) were detected at 10 and 14 hours of illumination duration, while the greatest - at 8 and especially at 16 hours duration. At the same time, the highest integral level of nutritional and vitamin value of products according to the totality of biochemical characteristics is set at 14 hours of illumination, while the minimum is at 8 hours.

A comprehensive root cause analysis of anammox bioreactor performance decline

The cultivation of anaerobic ammonia oxidizing bacteria (anammox) has gained enormous awareness over the last few decades. Although numerous studies focus massively on successfully growing these anammox to different enrichment environments, in reality, the failure rates are somewhat comparable to the reported success rates. This study combines a variety of measurement techniques to observe and monitor the sequence of a bioreactor performance decline following elevated influent substrate concentration. After attaining stable substrate removal throughout a nitrogen loading rate (NLR) range of 0.691 to 1.669 kg-N·m−3·d−1, the performance of the lab-scale anammox-sequencing batch reactor (SBR) abruptly broke down as the NLR reached 2.01 kg-N·m−3·d−1. The gathered information showed that the increased NLR firstly caused a significant and unfavorable change in the free ammonia (FA) and free nitrous acid (FNA) concentration in the bioreactor. A subsequent drop in N2 production and a decline from a peak high of 0.381 to a low of 0.012 kg-N·kg-VSS−3·d−1 of the specific nitrogen removal rate (SNRR) led to an 82% absurd decline in microbial cellular energy production. Prior to these anammox switching to survival mode and secreting larger quantities (32% higher) of extracellular polymeric substances (EPS), the activity of syntrophic decomposers increased substantially leading to the internal production of excess CO2 in the bioreactor and thereby diverging the bioreactor pH to lower levels. The purposes of this study are to understand the reason an anammox process shows different signals during a decline phase and to enable immediate response to performance deterioration.

Roles of mannosylerythritol lipid-B components in antimicrobial activity against bovine mastitis-causing Staphylococcus aureus

Mannosylerythritol lipid-B (MEL-B), which comprises ester-bonded hydrophilic ME and hydrophobic fatty acids, is a bio-surfactant with various unique properties, including antimicrobial activity against most gram-positive bacteria. The gram-positive Staphylococcus aureus is a causative pathogen of dairy cattle mastitis, which results in considerable economic loss in the dairy industry. Here, we demonstrate the efficacy of MEL-B as a disinfectant against bovine-derived S. aureus and elucidate a mechanism of action of MEL-B in the inhibition of bacterial growth. The growth of bovine mastitis causative S. aureus BM1006 was inhibited when cultured with MEL-B above 10 ppm. The activity of MEL-B required fatty acids (i.e., caprylic and myristoleic acids) as ME, the component of MEL-B lacking fatty acids, did not inhibit the growth of S. aureus even at high concentrations. Importantly, ME-bound fatty acids effectively inhibited the growth of S. aureus when compared with free fatty acids. Specifically, the concentrations of ME-bound fatty acids and free caprylic and myristoleic acids required to inhibit the growth of S. aureus were 10, 1442, and 226 ppm, respectively. The involvement of ME in the antimicrobial activity of MEL-B was confirmed by digestion of MEL-B with alkali, which dissociated ME and fatty acids. These results indicated that a mechanism of action of MEL-B in inhibiting the growth of S. aureus could be explained by the effective transporting of antimicrobial fatty acids to the bacterial surface via hydrophilic ME.

Chemical Composition Analysis and Antioxidant Activity of Coffea robusta Monofloral Honeys from Vietnam.

Monofloral honey samples (Coffea robusta) from Vietnam were determined for their chemical compositions. This is the first report on the chemical composition and antioxidant activity of coffee honey from Vietnam. These samples were characterized by their high contents of total and reducing sugars, total phenolic contents, and total flavonoid contents. The contents of seven phenolic acids (PAs) were quantified by high performance liquid chromatography (HPLC) and analyzed with the assistance of principle component analysis (PCA) to differentiate the honey samples into groups. The hydroxymethylfurfural (HMF) (0.048–2.933 mg/kg) and free acid contents (20.326–31.163 meq/kg) of coffee honey were lower in Nepal, which reflected the freshness of the honey when conducting this survey. The coffee honey had total sugar and reducing sugar contents 831.711 g/kg and 697.903 g/kg, respectively. The high level of total phenolic (0.642 mg GAE/g) and flavonoid (0.0341 mg GE/g) contents of coffee honey contributed to their antioxidant activity of this honey sample. Among the coffee honey tested, the IC50 of DPPH radical-scavenging activities value was 1.134–17.031 mg/mL, while the IC50 of ABTS radical-scavenging activities value was 115.381–213.769 mg/mL. The phenolic acids composition analysis displayed that gallic acid appeared in high concentrations in all studied honey samples, ranging from 0.037–1.015 mg/kg, and ferulic acid content ranged from 0.193 to 0.276 mg/kg. The content of trigonelline and caffeine in coffee honey samples ranged from 0.314–2.399 mg/kg and 8.946–37.977 mg/kg. The data in this article highlight the relevance of coffee honey as a healthy substance.

Assessing Nutritional Quality and Shelf life of Broccoli Cultivars

Inadequate knowledge on the nutritional and shelf life of broccoli render growers and consumers to poorly utilize this vegetable. To disseminate proper information on nutrition and storage it’s imperative to determine the nutrient content and shelf life of the modern cultivated broccoli cultivars. In this regard, five broccoli cultivars viz. Green Magic, Green Giant, Top Green, Early Green and Green Imported were evaluated to determine the nutritional and shelf life quality. A factorial Completely Randomized Design (CRD) with three replicates was used for experimentation. Data were collected on different vitamin, minerals and storage conditions (temperature, packaging). Collected data were statistically analyzed with the help of computer program MSTATC. Outcomes noted that, under fresh condition highest free ascorbic acid content (49.11mg/100g) was recorded in Green Magic. Green Giant had the maximum amount (1.07 mg/100gm) of b-carotene, reducing sugar (4.10 g/100g) and non-reducing sugar (1.53 g/100g). Green Imported had the most content of iron (162.71 ppm), calcium (0.85%) and magnesium (0.33%); while most amount of phosphorus (0.24%) was noted in Green Magic. The peak amount of potassium (0.99 %) and magnesium (0.33%) was found in Green Giant. The longest shelf life was obtained from Green Magic at 4°C (21.83 days) under polyethylene packaging condition. Hence it was noted that, shelf life and temperature had a vice versa relationship.

Sweet corn cob as a functional ingredient in bakery products

Gluten free (GF) products are often inferior in quality attributes, nutritional content and consumer acceptability. The use of GF by-products is a novel strategy to improve the structure and nutritional profile of these products. Sweet corn cob (SCC) is a by-product of sweet corn processing containing a considerable amount of fibre and ferulic acid. The effect of baking on ferulic acid content, colour, texture and physical characteristics on muffins incorporated with SCC flour (SCCF) as a value-added food ingredient was investigated using a GF model system. The freeze-dried SCCF, containing ferulic acid (6.02 mg g−1) was used to replace the rice flour at varying levels of 10, 20, and 30%. In general, SCCF increased dietary fibre and free ferulic acid content of muffins. Inclusion of 20% SCCF showed an increase in terms of the height of the muffin and number of air cells in the crumb, along with a decrease in the hardness of muffins. Muffins with SCCF showed higher mean overall liking scores than rice flour muffin.

The Identification of Sialuria with Different Degrees of Intellectual Disabilities in Children and Adolescents

Background: Single nucleotide polymorphism/mutation in the R263L region of the allosteric site of the GNE gene produces a phenotype with an overproduction of intracellular levels of sialic acid and causes sialuria. In sialuria, a defective GNE gene, synthesized with lost feedback inhibition mechanism, produces many developmental delays and varying degrees of intellectual disabilities in children and adolescents. Several mutations in the epimerase and kinase domains exist that cause difficulty in getting a precise and exact effect of the GNE gene on the disease severity and sialic acid levels. This is the first study investigating the molecular basis of neuronal disorders exhibiting sialuria in Pakistani children/ adolescents.
 Methodology: The current study quantified the mRNA expression of the GNE gene and urinary sialic acid concentration by Realtime-qRT-PCR and Fluorimetric assays, respectively. The correlation between relative mRNA and urinary sialic acid levels was evaluated by using Pearson Bivariate correlations.
 Results: The data show that severely intellectually disabled (I.D.) patients showed significantly reduced mRNA expression levels of the GNE gene compared to controls. The concentrations of free sialic acid in urine were significantly reduced in severe I.D. patients compared to controls. Whereas patients with mild I.D. showed a two-fold increase in sialic acid levels when compared to controls. A significant correlation was found between an increased GNE mRNA and low urinary sialic acid levels from severe I.D. patients.
 Conclusion: The effect of the GNE gene is beyond hyposialylation that could hinder N-glycan structure and sialic acid biosynthesis. The study highlighted the possible involvement of sialic acid levels with different degrees of intellectual disabilities in Pakistani children and adolescents.

Determination of Free Valproic Acid Concentration in 569 Clinical Samples by LC-MS/MS After Hollow Fiber Centrifugal Ultrafiltration Treatment.

To perform therapeutic drug monitoring of total and free plasma valproic acid (VPA) concentrations in clinical samples and to analyze the related factors. The total VPA concentration in plasma was determined by ultrahigh-performance liquid chromatography with precolumn derivatization with α-bromoacetophenone, and the free VPA concentration was determined by liquid chromatography-tandem mass spectrometry after the plasma was treated by hollow fiber centrifugal ultrafiltration. Regression analysis was performed to examine the associations between free plasma VPA, total plasma VPA, and the plasma protein binding rate. The impact of individual situations, outpatient or inpatient factors, and drug combinations on VPA concentrations were examined. Of the 569 clinical samples, 268 were inpatients and 301 were outpatients, and the total VPA concentration in 138 cases (24.2%) was lower than the effective treatment concentration range; the total and free VPA concentrations in outpatient samples were 11.0% and 26.1% higher than those of inpatients, respectively. There was no linear relationship between the free and total VPA concentrations. The relationship equation between the plasma protein binding rate and free VPA concentrations was as follows: Y = 0.0255X2 - 1.1357X + 97.429 (r = 0.8011). The total and free VPA concentrations were significantly decreased after the coadministration of phenobarbital (83.7% and 64.3% of the control group, P < 0.05) or carbapenem antibiotics (32.0% and 32.7% of the control group, P < 0.05). The total VPA concentrations in patients with epilepsy at our hospital was lower than the effective treatment concentration range, which was inadequate for epilepsy control; the total VPA concentrations of outpatients were higher than those of inpatients; as phenobarbital affects VPA metabolism, therapeutic drug monitoring is recommended. Carbapenem antibiotic coadministration with VPA should be avoided because carbapenem antibiotics can lead to the failure of VPA antiepileptic treatment.

Beekeeping Practices, Physiochemical Properties and Consumer Acceptability of Honey Collected from the Forest and Backyard Hives in Pandamatenga, Botswana

Beekeeping is an important agricultural activity in Botswana and supports the livelihoods of many people in the country. However, there is limited documented evidence on apicultural practices and quality of honey produced in different parts of the country. Pandamatenga village is located in north-eastern part of Botswana and is characterized by a hot semi-arid climate and dense natural vegetation cover. Due to its fertile soil and better rainfall relative to other parts of the country, Pandamatenga area has high agricultural potential. This study was conducted to assess beekeeping practices and determine the physicochemical properties and consumer acceptability of honey produced in Pandamatenga village. Honeybee production practices were assessed by conducting questionnaire survey. Three honey samples were obtained each from backyard hives and the forest and analysed for their physicochemical properties. Consumer acceptability test was also conducted on the honey samples using 9-point hedonic scale. Honey samples collected from backyard hives had an average moisture (%), total ash (%), free acidity (meq/㎏), pH, reducing sugars (%), sucrose (%) and Hydroxymethylfurfural (HMF) (㎎/㎏) contents of 16.93±0.23, 0.13±0.042, 11.00±0.01, 6.67±0.01, 56.60±0.34, 1.54±0.00 and 26.00±0.10, respectively. The corresponding values for honey samples collected from the forest were 24.87±0.23, 0.35±0.144, 67.00±1.52, 4.28±0.02, 56.93±0.18, 1.17±0.14 and 33.17±0.60, respectively. Moisture, free acidity and HMF contents of forest honey samples were significantly higher (p＜0.05) than the corresponding values for backyard honey. On the other hand, the pH and sucrose contents of backyard honey samples were significantly higher (p＜0.05) than the corresponding values for forest honey. Backyard honey had significantly higher scores (p＜0.05) for colour, appearance and grassy aroma as compared to forest honey. The survey result showed that Pandamatenga area has a big potential for honey production with an average of 20.7 liters of honey produced per household per year. In conclusion, honey produced in Pandamatenga area is of good quality and all the honey samples analysed were within the limits of international standards for honey.

The effect of pro-ecological procedures and plant injury on the content of free phenolic acids in winter wheat and on the feeding and development of Oulema melanopus

Under laboratory conditions we have investigated the effect of the application of pro-ecological procedures (effective microorganisms and biostimulant Asahi SL) and plant injury on the production of free phenolic acids in winter wheat and on the feeding and development of Oulema melanopus. Wheat plants before reaching the BBCH 32 stage (the beginning of stem elongation) were treated with effective microorganisms and the biostimulant Asahi SL. Then, for 2 days, some of the plants were injured by O. melanopus and some were uninjured. The influence of factors was investigated in conditions under which the cereal leaf beetle had the possibility to choose their food (no-choice test or choice test). It was found that wheat plants produce on average 0.172% DM of free phenolic acids. It has been shown that O. melanopus males and females preferred wheat previously uninjured. Also, irrespective of whether the plants were previously injured or uninjured, the females of that pest species always that caused areally more extensive leaf losses than the males. Treating plants with effective microorganisms and biostimulant Asahi SL is a secondary factor, as compared to previous wheat injury. Additionally, in choice tests, both males and females O. melanopus much preferred feeding on plants unprovided with preparations, whereas in no-choice tests, the application of pro-ecological procedures does not reduce egg laying by pests, does not adversely affect embryogenesis length and does not reduce hatching L1.

Alteration of phenolics and antioxidant capacity of gluten-free bread by yellow pea flour addition and sourdough fermentation

Gluten-free bread is often characterised by poor nutritional value and bioactive profile. Legume flours have potential for its enrichment, but the effect of sourdough fermentation of legume matrices on the phenolics and antioxidant capacity of bread is scarcely investigated. Thus, this study aimed to determine the effect of partial replacement (25%) of wholemeal rice flour with yellow pea flour on phenolics and antioxidant capacity of gluten-free sourdough and bread. Sourdough was fermented with Lactobacillus reuteri DSM 20016, Lactobacillus fermentum DSM 20052 or Lactobacillus brevis DSM 20054. Free phenolic acids (protocatechuic, 4-hydroxybenzoic, vanillic and ferulic), lactic and acetic acid content was determined by HPLC, and free total phenolic content (TPC), DPPH and FRAP antioxidant capacity by spectrophotometric methods.After 16 h of fermentation, total titrable acidity of the sourdough ranged from 11.85 to 18.97 mL of 0.1 M sodium hydroxide, with lactic/acetic acid content of 2.65–9.41. Yellow pea flour addition substantially increased protocatechuic acid and 4-hydroxybenzoic acid content, but decreased the antioxidant capacity of unfermented dough and bread. Depending on the starter, the sourdough fermentation of pea-rice flour blend and its addition to bread increased the phenolic acid content, TPC and antioxidant capacity. Bread with yellow pea flour and L. brevis sourdough showed the highest improvement in phenolic acid content (40%), TPC (44%) and antioxidant capacity (30% DPPH, 50% FRAP) compared to bread without added sourdough. The study demonstrates the importance of using sourdough fermentation with a carefully selected starter when adding pea flour to gluten-free bread to ensure high antioxidant potential.

Use of a packed-bed biofilm reactor to achieve rapid formation of anammox biofilms for high-rate nitrogen removal

Anammox is an efficient and carbon-saving process for biological nitrogen removal; however, the long start-up period and poor stability of anammox bioreactors hinder their application in wastewater treatment. An innovative technical strategy was developed in this study that used a packed-bed biofilm reactor (PBBR) to grow healthy anammox biofilms for the fast start-up of bioreactors. With a greatly reduced fluid turbulence in the PBBR, the attachment and growth of anammox biofilms were found to be accelerated and the specific anammox biofilm formation rate was 60% higher than that in the conventional moving-bed biofilm reactor (0.032 vs. 0.020/d). In the PBBR operation, maintaining a low free ammonia (<2.7 mg/L) and free nitrous acid (<5.8 μg/L) concentrations in the early stage and stepwise increasing the nitrogen load also assisted the biofilm formation. With the rapid anammox biofilm formation and growth, the nitrogen removal capacity of the PBBR increased from 77.6 to 876.8 mg N/(L·d) in 2 months. The anoxic condition and prolonged sludge retention time in the PBBR also benefited the growth of fermentative bacteria and denitrifiers, which induced the partial denitrification–anammox process and decreased the nitrate accumulation by 50%.