High Phenol Research Articles

Preparation of adsorbent from coal gasification slag for the treatment of waste water from lanchar and its adsorption mechanism

ABSTRACT Solid waste coal gasification slag has certain hardness, porosity, pore structure and specific surface area, etc. which can be utilized in environmental protection materials and other areas of high value. Yulin City, high-quality coal resources derived from the excellent quality of charcoal products, but its processing will produce a large number of high chemical oxygen demand (COD), high volatile phenol, high ammonia nitrogen ‘three high’ wastewater, the ecological environment is very harmful. The results of the modification of the refined coal gasification fine residue showed that the removal rates of the three were enhanced to 91%, 89% and 83%, respectively, after adsorption at a pH of 9.5, an injection ratio of 1:5 and 25 ℃ for 25 min. The reason is that the modification treatment significantly increased the specific surface area of the adsorbent from 103 m2/g to 606 m2/g, which effectively increased the adsorption active sites for the pollutant molecules. The adsorption process of COD from modified refining coal gasification slag for the treatment of charcoal wastewater was thermodynamically investigated. The thermodynamic study shows that the adsorption process of modified refining coal gasification slag on pollutants in the charcoal wastewater is an exothermic and spontaneous process.

Efficient Electrosynthesis of Valuable para-Benzoquinone from Aqueous Phenol on NiRu Hybrid Catalysts.

Electrocatalytic oxidation of aqueous phenol to para-benzoquinone (p-BQ) offers a sustainable approach for both pollutant abatement and value-added chemicals production. However, achieving high phenol conversion and p-BQ yield under neutral conditions remains challenging. Herein, we report a Ni(OH)2-supported Ru nanoparticles (NiRu) hybrid electrocatalyst, which exhibits a superior phenol conversion of 96.5% and an excellent p-BQ yield of 83.4% at pH 7.0, significantly outperforming previously reported electrocatalysts. This exceptional performance benefits from the triple synergistic modulation of the NiRu catalyst, including enhanced phenol adsorption, increased p-BQ desorption, and suppressed oxygen evolution. By coupling a flow electrolyzer with an extraction-distillation separation unit, the simultaneous phenol removal and p-BQ recovery are realized. Additionally, the developed electrocatalytic system with the NiRu/C anode displays good stability, favorable energy consumption, and reduced greenhouse gas emissions for phenol-containing wastewater treatment, demonstrating its potential for practical applications. This work offers a promising strategy for achieving low-carbon emissions in phenol wastewater treatment.

Efficient Electrosynthesis of Valuable para‐Benzoquinone from Aqueous Phenol on NiRu Hybrid Catalysts

Electrocatalytic oxidation of aqueous phenol to para‐benzoquinone (p‐BQ) offers a sustainable approach for both pollutant abatement and value‐added chemicals production. However, achieving high phenol conversion and p‐BQ yield under neutral conditions remains challenging. Herein, we report a Ni(OH)2‐supported Ru nanoparticles (NiRu) hybrid electrocatalyst, which exhibits a superior phenol conversion of 96.5% and an excellent p‐BQ yield of 83.4% at pH 7.0, significantly outperforming previously reported electrocatalysts. This exceptional performance benefits from the triple synergistic modulation of the NiRu catalyst, including enhanced phenol adsorption, increased p‐BQ desorption, and suppressed oxygen evolution. By coupling a flow electrolyzer with an extraction‐distillation separation unit, the simultaneous phenol removal and p‐BQ recovery are realized. Additionally, the developed electrocatalytic system with the NiRu/C anode displays good stability, favorable energy consumption, and reduced greenhouse gas emissions for phenol‐containing wastewater treatment, demonstrating its potential for practical applications. This work offers a promising strategy for achieving low‐carbon emissions in phenol wastewater treatment.

Micronized Rose Petal Powder: A Valuable Edible Floral Food Ingredient Containing Bioactive Compounds

Flower petals, as byproducts, provide significant health benefits and can be used in food production. In this study, the impact of the micronization process using a ball mill on the properties of micronized powders derived from wild rose petals of the rugosa variety (Rosa rugosa Thunb.) was examined. The micronized rose powders were subjected to an investigation regarding their particle size, color, molecular characterization (FTIR), electronic nose procedure and antioxidant potential. The study found that micronization considerably reduced d50 particle dimensions from 98.6 µm to 39.9 µm. An FTIR analysis revealed the presence of characteristic (2980, 1340, and 1225 cm−1) bands. The hydrolysable tannins are the most abundant polyphenolic chemicals in rose powders, followed by anthocyanins. Rose powders are an extremely valuable antioxidant raw material due to their high total phenol content (71.8 mg GAE/g), which increased by approximately 26% after micronization. The antioxidant activity, as determined by ABTS•+, DPPH• and FRAP, is likewise very high. The intensity of volatile chemicals decreased in powders after micronization.

Recycling Valuable Phenol from Polycarbonate Plastic Waste Via Direct Depolymerization and Csp2-Csp3 Bond Cleavage Under Mild Conditions.

Upcycling plastic waste into commodity chemicals is recognized as an environmentally benign solution and beneficial for the sustained growth of humanity. Nevertheless, transition metal-free catalysts and energy-efficient conditions pose significant challenges due to the robust mechanical properties of plastics. Here, a strategy for selective production of phenol by upcycling polycarbonate waste via direct depolymerization and Csp2-Csp3 bond cleavage in an aqueous medium under mild conditions is reported. The commercial zeolites efficiently catalyze the depolymerization, Csp2-Csp3 bond hydrolysis, and direct Csp2-Csp3 bond scission at Cα of PC. Among all evaluated zeolites, HY (Si/Al=15) showed excellent catalytic performance, attributed to the ~75 % yield of phenol and ~15 % of acetone. The approach also employs different municipal waste PC for upcycling. Studies reveal that HY (15) exhibits high catalytic efficiency and phenol yield due to its optimum acid sites and textual properties. A scale-up experiment demonstrated that 3.1 g of phenol was produced from 5.0 g of PC, and the mass balance was 90 %. A combination of control experiments, NMR analysis, and DFT studies proposed the reaction pathway. Our findings present a sustainable avenue for upcycling PC waste and offer a new way to produce phenol, contributing to the advancement of a circular economy.

Investigating the phytochemical profile, biological potentials, morphological, and anatomical characteristics of Cyclotrichium origanifolium (Labill.) Manden. & Scheng. (Lamiaceae) from Turkey.

Cyclotrichium origanifolium, a plant widely used in Eastern and Southern Anatolia for culinary purposes, was subject of this study, which aimed to comprehensively evaluate its potential therapeutic applications. This research stands out due to its holistic approach, combining morpho-anatomical studies, chemical, and biological analyses to explore antioxidant, antidiabetic, anticholinesterase, genotoxic, and anti-genotoxic effects of methanolic and aqueous extracts, as well as flowering aerial part essential oil. It is a perennial plant, typically ranging from 10 to 40cm in height, with a suffrutescent and highly branched growth habit. Essential oils are produced within glandular trichomes. Oil, analyzed via GC-MS/MS, revealed 24 compounds accounting for 96.4% of oil, with isomenthone (52.4%), pulegone (23.4%), and β-pinene (9.5%) as predominant components. These findings are significant as they provide new insights into chemical composition of oils, particularly highlighting pharmacologically active compounds. Methanol extract exhibited superior antioxidant activity, correlated with high phenol and tannin content. Essential oil showed moderate inhibition of α-amylase (49.54%) and mild inhibition of acetylcholinesterase (11.84%) and butyrylcholinesterase (16.93%), suggesting potential in managing oxidative stress and neurodegenerative diseases. Study also conducted biosafety evaluations using Ames/Salmonella and Allium tests, essential for assessing genotoxic and antigenotoxic potential of natural products. Notably, significant antimicrobial effects were identified, particularly against Pseudomonas aeruginosa and Enterococcus faecalis. Comprehensive analysis and discovery of significant bioactivities position this research as a valuable contribution to field, distinguishing it from previous studies on similar species. This study provides a foundational understanding of morpho-anatomical, pharmacological, biological properties of plant, opening avenues for future research.

Metal oxide particle electrodes for degradation of high concentration phenol wastewater via electrocatalytic advanced oxidation

High-concentration phenol wastewater is pollutant of concern that pose significant risks to human health and the environment. Three-dimensional electrocatalytic oxidation is one of the most promising wastewater treatment technologies because of its high treatment efficiency, low energy consumption and low secondary pollution. Lower-cost and higher-performance particles still faces great challenges. In this work, metal oxide particle electrodes were prepared using granular activated carbon (GAC) as a substrate to study the degradation of phenol by three-dimensional electrocatalytic oxidation. GAC particle electrodes loaded with different monometallic oxides (Mn, Fe, Co, Ce) and bimetallic oxides (Fe and Ce) were prepared by the impregnation method. The effectiveness of the particle electrodes in degrading phenol was greatly improved after active components loading. Among all monometallic oxide particle electrodes, the concentration degradation efficiency was in the order of Ce/GAC > Co/GAC >Mn/GAC > Fe/GAC, and the COD degradation efficiency was Ce/GAC > Fe/GAC > Co/GAC >Mn/GAC. After optimizing the loading metal type and loading amount, it was found that the 1.1% Fe-2.7% Ce/GAC particle electrode perform the best, with a phenol degradation efficiency of 95.48%, a COD degradation rate of 94.35%, an energy consumption of 0.75 kWh/kg COD. This lower-cost and higher-performance particle highlights a reliable route for solving the problem of particle electrode materials limiting the efficient treatment of phenol-containing wastewater.

Alfalfa sprout flour: A promising ingredient to improve probiotic survival and antioxidant activity in mint-flavored stirred yogurt

This study examined the impact of alfalfa sprout flour (ASF) on the pH, titratable acidity (TA), syneresis, water-holding capacity (WHC), color attributes, antioxidant potential, survival of Lactobacillus acidophilus LA-5, and sensory properties of mint-flavored stirred yogurt over 24 days of cold storage. Four probiotic yogurt batches were prepared, namely plain probiotic yogurt (PPY), mint-flavored probiotic yogurt (MFPY), and MFPY with 0.5 and 1% w/w of ASF (MFPY-ASF-0.5%, and MFPY-ASF-1%). Yogurt with added ASF exhibited the highest increase in TA (18.80-24.40%) and a decrease in pH (0.18). L. acidophilus maintained the highest survival rate (7.3-7.43 Log CFU/g) in MFPY-ASF-1% yogurt between days 8 to 24 of storage, exceeding the minimum count recommended for the therapeutic effects of probiotics. PPY and MFPY demonstrated significantly lower WHC and higher syneresis values compared to MFPY-ASF-0.5% and MFPY-ASF-1% (P < 0.05). The addition of mint and ASF remarkably decreased lightness (L*) and increased yellowness (b*) and greenness (-a*) values of samples compared to PPY. All flavored samples exhibited a gradual decrease in b* and -a* values, alongside an increase in L* values, during storage. ASF-enriched yogurts showed high total phenol content, total flavonoid content, and antioxidant activity. Although an increase in ASF levels resulted in a reduction in consumer preferences for odor and flavor, all samples received satisfactory overall acceptability scores (3.05-4.30) at the end of storage. In conclusion, the inclusion of ASF at the 1% level presents a promising opportunity for producing value-added yogurt with enhanced probiotic survival, antioxidant activity, and favorable technological properties.

Exergy analysis of process configurations for phenol recovery from wastewater

Wastewater with high phenol content, primarily generated by the petrochemical, coal, oil, and gas industries, must be treated before disposal to meet global regulations and prevent environmental harm. Liquid-liquid extraction is a well-studied method employed to address this need. Despite the extensive focus on to energy performance, exergy analysis has not yet been incorporated. Therefore, this study aims to compare four process configurations by integrating an exergetic approach with economic and emissions analyses to quantify thermodynamic efficiency, total annual cost, and CO2 emissions. Process simulations were conducted using Aspen Plus V.12, and the economic analysis was performed using the Aspen Process Economic Analyzer. The input streams of all configurations were 100 ton/h of wastewater containing 275 kg/h of phenol and 266 kg/h of hydroquinone, with pure methyl iso-butyl ketone (MIBK) as the makeup solvent. Extraction and mixing exhibited the lowest exergy destruction, while distillation accounted for approximately 55 % of the total exergy destruction. Configurations that incorporated direct medium-pressure steam input resulted in greater exergy destruction, leading to reduced exergy efficiency, but a lower total annual cost. The most economical configuration was achieved by heat integration of De Dietrich® process with low-pressure steam (C-IE lps), benefiting from exergy analysis insights. The exergy efficiency of this configuration increased from 33 % to 38 %, and the total annual cost decreased by 183 thousand USD per year compared to the initial De Dietrich® process (configuration C). Similarly, CO2 emissions were reduced to the lowest level, reaching 4.87 kg CO2 /h.

Effect of low molecular weight phenols on the in-mouth sensory perception of high molecular weight phenols by analyzing reconstituted wines

This research aimed to assess the contribution of monomeric phenols to the perception of bitterness and astringency by means of wine reconstitution experiments. Six wines with distinct total polyphenol indexes were selected and fractioned by preparative liquid chromatography into two fractions. Thirty-one reconstituted wines were prepared by combining distinct low molecular weight fractions (L) with different high molecular weight fractions (H). In-mouth attributes of reconstituted and reference wines were described by a trained sensory panel. Fractions were chemically characterized by UPLC-MS. No significant differences among sensory results were found between reference and reconstituted wines. Bitterness and astringency perception were strongly influenced by total proanthocyanidins content. Flavan-3-ol monomers and dimers were only responsible for astringency in wines with a low content of proanthocyanidins, as was the case in rosé wine. Quercetin-3-O-glucuronide and several anthocyanins presented correlations with bitterness in the reconstituted wines; notwithstanding, several interactions with this attribute were observed.

Effect of drying techniques, conditions and feed types on the quality of dried curry leaf powder

Curry leaf (Murraya koenigii L.) is valued for its characteristic flavor and is used in varied cuisines and formulations. In this work, the effect of three different drying techniques: tray drying (TD), conductive hydro drying (CHD), and freeze drying (FD), at varying temperatures (40 °C, 60 °C, 80 °C) on the phytochemical and physical properties of curry leaf dried as leaf or as pulp was evaluated. Drying behavior was studied using the Page model and effective diffusivity was found to increase with temperature. CHD at 40 °C resulted in the lowest moisture content (4.98 ± 0.03 %) while FD resulted in the lowest water activity (0.54 ± 0.04). Excellent flow properties were observed in TD 60 °C and CHD 80 °C. However, CHD at 40 °C exhibited superior color retention. TD 80 °C and CHD 80 °C, with reduced drying duration resulted in higher phenolics, flavonoids and alkaloid contents. On the contrary, CHD 40 °C sample showed better antioxidant activity and flavor retention through GC–MS. Similarly, SEM analysis showed intact cell structures in samples dried at lower temperatures. Overall, considering drying time, product quality, and process costs, CHD, often regarded as a nonthermal approach, is an excellent approach for the production of curry leaf powder.

A novel strategy for Klebsiella sp. to resist high salt and high phenol environmental stress

Isolating high-performance phenol degradation microorganisms with high salt tolerance and studying their resistance mechanisms are urgent issues. To address these issues, a typical bacteria (Klebsiella sp. YP-1) with high salt and phenol tolerance was isolated. Its strategies for resisting high salt and high phenol stress were studied. The results indicated that Klebsiella sp. YP-1 was able to degrade 1000 mg/L phenol within 44 h at 70 g/L NaCl, which was faster than most microorganisms reported in the literature. Lyxose secreted by Klebsiella sp. YP-1 played an important role on assisting Klebsiella sp. YP-1 to resist stress. Lyxose increased phenol degradation rate by microorganisms due to its protection on cell membrane. Quantum chemical calculation results indicated that lyxose was more likely attacked by free radical than cell membrane. In addition, lyxose could bind to the cell membrane through hydrogen bonds. Thus, lyxose prevented reactive oxygen species from harming cell membranes. Moreover, lyxose has broad protective effect on microbial cell membranes. This study provides a novel idea for microorganisms to resist oxidative stresses.

Eryngo essential oil nanoemulsion stabilized by sonicated-insect protein isolate: An innovative edible coating for strawberry quality and shelf-life extension

New bioactive coatings with eryngo essential oil (EEO) nanoemulsions stabilized by ultrasonically-treated lesser mealworm protein isolate (LMPI) were developed to extend strawberry shelf life and quality. EEO due to high carvone (43.03 %), phenolics (87.45 mg gallic acid equivalent/g), flavonoids (13.56 mg quercetin equivalent/g), and carotenoids (635.07 mg/kg) contents exhibited a significant antioxidant activity comparable to ascorbic acid (AA) and BHT. Nanoemulsions stabilized with 9 % sonicated LMPI showed smaller droplet size, higher negative ζ-potential, and greater stability, turbidity, and encapsulation efficiency of EEO compared to those stabilized with native LMPI. The FTIR spectra showed that sonicated LMPI had structural changes enhancing its emulsifying activity, with key peaks indicating the presence of hydrogen bonds, carbonyl groups, and protein conformations in both EEO and LMPI. Strawberries coated with optimal EEO-loaded nanoemulsions showed superior quality with minimal storage-dependent physicochemical, textural, color, and sensory changes compared to control samples. This edible coating also maintained higher total monomeric anthocyanin and AA contents with lower peroxidase activity during storage than EEO-based coatings. However, no significant difference in superoxide dismutase activity between samples covered by EEO and EEO-loaded nanoemulsions over 14 days of storage was found. Bioactive nanoemulsions stabilized by insect proteins would be an eco-friendly and safe approach to upholding quality standards in stored fruits and vegetables.

Profiling of phytochemical constituents of terminalia chebula fruit extract by different solvent effects and synchronized analysis of FTIR and GCMS

BackgroundDetecting the Teminalia chebula best extract-enriching bioactive compounds using four different solvents; Ethanol, water, chloroform and petroleum ether for medicinal applications. MethodsQualitative analysis of phytochemicals of T. chebula (such as Tannins, saponins, flavonoids, alkaloids, terpenoids); Quantitative Determinations (Condensed tannins; total flavonoids, and phenolics), also, determination of enzymatic and non-enzymatic antioxidants. GC–MS and FT-IR analysis of ethanolic extract were investigated. ResultsThe assays for phenolics, tannins and total flavonoids indicated an extensive difference in the total phenolic content ranging from 26 to 104, 13 to106 and 106 µg/g of extract. It was found that, the highest phenolics, tannins and total flavonoids content were found in the ethanolic extract and the lowest by petroleum ether extract. In examining the amount of total protein content also, high amount of total proteins observed in the ethanolic extract as 67 µg/g whereas, in contrast, the high amount of total carbohydrates observed in the aqueous extract with 103 µg/g. Further, the level of the different enzymatic antioxidant markers (SOD, Catalase and Gpx) and non-enzymatic antioxidant markers (vitamin C and vitamin E) produced by the ethanolic T. chebula fruit extract were 0.46 µg, 97 µg and 127 µg and 39.08 µg and18 mg/liter. The DPPH and reducing power assay radical scavenging activities of different solvent extracts of T. Chebula exhibited free radical scavenging properties up to 96 % of inhibition. The functional groups of the components were separated based on its peaks through FTIR analysis showed the existence of alcohol, alkanes, carboxylic acid, alkenes, alkanes, ethers, halogen respectively. The active compounds identified based on GCMS analysis showed the presence of furaldehyde, 2,5-furandicarboxaldehyde Dodecanoic acid, ethylester n-pentadecanol, 1,2,3-Benzenetriol pyrogallol, 3,4,5trihydroxy benzoic acid, Octadecanoicacid,ethyl ester and Hentriacontane. ConclusionAmong four solvent screened, the ethanol extract of T. chebula revealed variety of bioactive phytochemicals. In addition to higher antioxidant activities and highest level of radical scavenging activity. Accordingly, it can be inferred that T. chebula may serve as an antibacterial, antifungal, anti-inflammatory, and anti-diabetic agent in addition to being a plant-based antioxidant.

Comparison of Volatile Organic Compounds, Quality, and Nutritional Parameters from Local Italian and International Apple Cultivars

Apple cultivars ‘Annurca’ and ‘Limoncella’ are grown locally in the Campania region of Italy and are valued for their distinctive flavour and characteristics, including a high content of nutritionally important bioactive compounds. However, apples are typically stored chilled for several months before consumption, so it is important to assess if the valuable characteristics are still present after postharvest storage. Here, we compare the quality, nutritional parameters, and aroma of these two cultivars with two widely grown international cultivars, ‘Golden Delicious’ and ‘Fuji’, after 60 days of storage. The aroma profiles of all four apples were analysed using thermal desorption and gas chromatography–time-of-flight mass spectrometry. We show that the local cultivars are distinct from the international cultivars in their bioactive compound content and their antioxidant activity. ‘Limoncella’ shows high sugar content, which may be acting as a cryoprotectant during storage, and high total phenolics in the flesh, which is of nutritional interest. We identified 104 volatile organic compounds (VOCs) and showed that the overall aroma profile is distinct for each cultivar, containing 11 published odorant compounds. The ‘Annurca’ profile is uniquely low in esters. Seven VOCs retain good discrimination across the four cultivars and, together with the quality and nutritional data, separate the two local cultivars from the international cultivars by hierarchical clustering. Overall, the data emphasize the unique characteristics of the two local cultivars and their value.

Decarboxylation of Hydroxybenzoic Acids to Phenol Via Deep Eutectic Solvents.

The development of greener and more sustainable synthesis processes for manufacturing commodity chemicals is of great importance. The majority of current phenol production methods involve harsh reaction conditions with high energy consumption, causing severe environmental pollution. In this study, we present a novel approach for the decarboxylation of hydroxybenzoic acids (HBAs) to phenol using a choline chloride-urea (ChCl-urea) deep eutectic solvent (DES). Our study reveals the remarkable dual performance of ChCl-urea both as a catalyst and solvent for the decarboxylation of HBA, resulting in a high phenol yield (94 mol %) under mild reaction conditions. The proposed reaction pathway, established through a combination of experiments and computational simulations, enhances our understanding of this process. The recyclability of the DES system during decarboxylation was also assessed. Our findings demonstrate that the integration of DES into conventional chemical processes can pave the way for sustainable manufacturing, exemplifying a novel approach for producing phenol from abundant natural resources using designer solvents.

Physicochemical, structural and functional properties of pomelo peel pectin extracted by combination of pulsed electric field and cellulase hydrolysis

In this study, pectin extracted from pomelo peel was investigated using three different combination methods of pulsed electric field (PEF) and cellulase. Three action sequences were performed, including PEF treatment followed by enzymatic hydrolysis, enzymatic hydrolysis followed by PEF treatment, and enzymatic hydrolysis simultaneously treated by PEF. The three corresponding pectins were namely PEP, EPP and SP. The physiochemical, molecular structural and functional properties of the three pectins were determined. The results showed that PEP had excellent physiochemical properties, with the highest yield (12.08 %), total sugar (80.17 %) and total phenol content (38.20 %). The monosaccharide composition and FT-IR analysis indicated that the three pectins were similar. The molecular weights of PEP, EPP and SP were 51.13, 88.51 and 40.00 kDa, respectively. PEP showed the best gel properties, emulsification stability and antioxidant capacity among the three products, due to its high galacturonic acid and total phenol content, appropriate protein and low molecular weight. The mechanism of PEF-assisted cellulase hydrolysis of pomelo peel was also revealed by SEM analysis. These results suggested that PEF pretreatment was the best method, which not only improved the efficiency of enzymatic extraction, but also reduced resource waste and increased financial benefits.

Co-pyrolysis of refinery oil sludge with biomass and spent fluid catalytic cracking catalyst for resource recovery.

Catalytic co-pyrolysis of two different refinery oily sludge (ROS) samples was conducted to facilitate resource recovery. Non-catalytic pyrolysis in temperatures ranging from 500 to 600°C was performed to determine high oil yields. Higher temperatures enhanced the oil yields up to ~ 24 wt%, while char formation remained unchanged (~ 45%) for S1. Conversely, S2 exhibited a notably lower oil yield (~ 4 wt%) than S1. Pyrolysis oil of S1 consisted of phenolics (~ 50% at 600°C) whereas hydrocarbons were predominant in S2 oil (~ 80% at 600°C). Catalytic pyrolysis of S1 did not exhibit a substantial impact on oil yields but the oil composition varied significantly. High hydrocarbons, phenolics, and aromatics were obtained with molecular sieve (MS), metal slag, and ZSM-5, respectively. Catalytic co-pyrolysis of S2 with sawdust (SD) in the presence of MS enhanced the oil yield, and the resulting oil consisted of high hydrocarbons (~ 54%) and aromatics (~ 44%).

The Effect of Fermentation Time Variation on Antioxidant Activity of Fermented Robusta Coffee Leaves (Coffea canephora Pierre ex A.Froehner) Brew

Antioxidants are electron-donor compounds that can delay, slow down and prevent free radical reactions. Fermentation is a chemical change that occurs due to the activity of microorganisms which can increase the amount of phenols in tea thereby increasing its antioxidant activity. Fermentation is carried out with the help of a Symbiotic Culture of Bacteria and Yeast (SCOBY) culture, which is commonly used in the production of kombucha. Kombucha is a fermented tea drink produced from leaves that contain high phenols such as robusta coffee leaves (Coffea canephora Pierre ex A.Froehner). Factors that affect the fermentation process are pH and fermentation time. This study aimed to explain the effect of fermentation time on the antioxidant activity of fermented robusta coffee leaves brew. Brewed robusta coffee leaves were made by brewing robusta coffee leaves simplicia powder, adding kombucha liquid starter, then fermented for 0; 3; 7; 14; and 21 days, then pH and antioxidant activity was measured using UV-Visible spectrophotometer using the 2,2-dipheny-1,1-picrylhydrazyl (DPPH) at a wavelength of 516 nm. This study showed that 0; 3; 7; 14; and 21 days fermented robusta coffee leaves brew have pH of 6,07; 4,62; 4,07; 3,21; and 2,74, and IC50 values is 285,1645 μg/ml; 219,7012 μg/ml; 192,2325 μg/ml; 187,0434 μg/ml; and 173,9249 µg/ml. There is an effect of fermentation time variation on the antioxidant activity of fermented robusta coffee leaves brew. Keyword: Antioxidant, Fermentation, pH, Robusta coffee leaves, Time variation

A novel simultaneous short-course nitrification, denitrification and fermentation process: bio-enhanced phenol degradation and denitrification in a single reactor.

The feasibility of a simultaneous nitrification, denitrification and fermentation process (SNDF) under electric stirrer agitation conditions was verified in a single reactor. Enhanced activated sludge for phenol degradation and denitrification in pharmaceutical phenol-containing wastewater under low dissolved oxygen conditions, additional inoculation with Comamonas sp. BGH and optimisation of co-metabolites were investigated. At a hydraulic residence time (HRT) of 28h, 15mg/L of substrate as strain BGH co-metabolised substrate degraded 650 ± 50mg/L phenol almost completely and was accompanied by an incremental increase in the quantity of strain BGH. Strain BGH showed enhanced phenol degradation. Under trisodium citrate co-metabolism, strain BGH combined with activated sludge treated phenol wastewater and degraded NO2--N from 50 ± 5 to 0mg/L in only 7h. The removal efficiency of this group for phenol, chemical oxygen demand (COD) and TN was 99.67%, 90.25% and 98.71%, respectively, at an HRT of 32h. The bioaugmentation effect not only promotes the degradation of pollutants, but also increases the abundance of dominant bacteria in activated sludge. Illumina MiSeq sequencing research showed that strain BGH promoted the growth of dominant genera (Acidaminobacter, Raineyella, Pseudarcobacter) and increased their relative abundance in the activated sludge system. These genera are resistant to toxicity and organic matter degradation. This paper provides some reference for the activated sludge to degrade high phenol pharmaceutical wastewater under the action of biological enhancement.