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Isolation of antimicrobial compounds from spent coffee grounds
Kurzová, Pavlína ; Veselá, Mária (referee) ; Kovalčík, Adriána (advisor)
Coffee grounds are one of the very valuable lignocellulosic wastes that have been able to be processed and used for isolated phenolic substances. Many phenolic substances isolated from lignocellulosic wastes have antimicrobial properties. Aim of this thesis is isolation phenolic substances from spent coffee grounds extract and their available antimicrobial properties. Two isolation ways were applied to receive phenolic substances from spent coffee grounds: 1) solvent extraction (hexane, 75% ethanol, 70% acetone, diethyl ether, and ethyl acetate) and 2) release of active substances by alcoholic fermentation. All isolated materials were characterized by the viewpoint of concentration of reducing sugars, polyphenols and flavonoids. Subsequently, their antimicrobial activity was determined by using agar diffusion and broth dilution methods. Two gram-positive bacteria (Bacillus subtilis and Micrococcus luteus), one gram-negative bacteria (Serratia marcescens) and two yeasts (Candida glabrata and Saccharomyces cerevisiae) were used for antimicrobial testing. High-performance liquid chromatography (HPLC) was used to identify phenolic substances in the extracts. First, the results showed that the isolated sample with the highest antimicrobial activity was 70% acetone extract. This extract contained chlorogenic acid, gallic acid, caffeic acid and coumaric acid according to HPLC. The ethyl acetate extract showed the lowest antimicrobial activity. Second, after lyophilization, the isolated materials also revealed high antimicrobial activity. The highest antimicrobial activity displayed the materials obtained by the extraction with 70% ethanol. This sample contained chlorogenic acid, gallic acid and caffeic acids. Next, samples with phenolic compounds were obtained by the alcoholic fermentation of spent coffee grounds. These samples showed similarly to the previous solution extracts significant antimicrobial activity. Interestingly, the unfiltered samples received directly after alcoholic fermentation also showed antifungal properties. The characterization of phenolic compounds by HPLC showed similarly as in previous examples that chlorogenic, caffeic and gallic acids were present in these samples.
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Biotechnological production of polyhydroxyalkanoates using wastes of coffee production
Vašíčková, Monika ; Benešová, Pavla (referee) ; Obruča, Stanislav (advisor)
This bachelor thesis is focused on study of production of polyhydroxyalkanoates (PHA) by bacteria Burkholderia cepacia and Burkholderia sacchari. Production of PHA has been studied using spent coffee grounds hydrolysates which have been prepared by different aproaches. In the thesis is compared standard method of coffee ground hydrolysis by mineral acid followed by enzymatic hydrolysis. Hydrolysates which have been produced were analyzed in terms of concentration of saccharides and efficiency of hydrolysis. The best producer of PHA (based on results) was bacterium Burkholderia cepacia, in the medium which has been prepared by hydrolysis of spent coffee grounds extracted by 60% solution of ethanol. Biomass yield of this cultivation was 3,553 g/l with 32,472% PHA content. This PHA contained 6,09% 3-hydroxyvalerate. In the other experiment, we verified alternative hydrolysis of spent coffee grounds – by commercially available enzymes. We used cellulase, hemicellulase and the enzymatic cocktail which has been produced by mould. Hemicellulase was the most effective hydrolytic enzyme and its application resulted in production of the highest amount of biomass – 5,708 g/l. In this cultivation, only homopolymer PHB has been which is probably caused by the fact, that during the enzymatic hydrolysis levulinic acid or any other potential precursor of 3HV is formed.
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Possibility of utilization of solid waste from spent coffee grounds rafination for agricultural purposes
Slavíková, Zuzana ; Vespalcová, Milena (referee) ; Pořízka, Jaromír (advisor)
The main focus of this diploma thesis is the utilization of spent coffee ground (SCG) and its biorefinery products in agriculture primarly as a prospective organic fertilizer. The study verifies an influence of the addition of native SCG as well as its acid hydrolysed, defatted and oxidized forms to experimental clay soil on chemical and physical properties (ph, conductivity and mineral content). Growing experiments were realized by using Lactuca sativa to detect positive or negative effects on growth. Samples of basic soil and soil with the addition of commercial NPK fertilizer served as a reference to measuring data. Measurements showed that addition of SCG and products of its biorefinery to the soil caused a decrease of pH and an increase of conductivity of soil samples. Significant increase of extractable calcium, magnesium, manganese and moderate increase of potassium content was detected. 2 % addition of SCG to soil had no impact on plants growth. The number and visual appearance of lettuces were comparable with plants in basic soil. No seed on acid hydrolysed samples germinated, which was caused by an increase of conductivity and sulphate content in these samples. In defatted and oxidized samples the early germination and the highest number of lettuces was observed. The low content of phosphorus in all soil samples had a great impact on growth rate and visual appearance of cultivated lettuces. In comparison with soil with NPK addition, lettuces in samples with SCG and its form had a pink-grey colour and lower growth.
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Use of wheat bran for fertilizer production
Maňáková, Helena ; Štursa,, Václav (referee) ; Diviš, Pavel (advisor)
This diploma thesis deals with the production of fertilizer from wheat bran and spent coffee grounds, which are produced in large quantities in the food industry. The efficiency of the removal of caffeine and phenolic substances from coffee grounds using the oxidation reason and the possibility of recycling the usable oxidizing effect were tested. We managed to oxidize almost all phenolic substances and a significant amount of caffeine from coffee grounds, even through the recycled oxidizing effect. Fertilizer in the form of pellets was subsequently formed from coffee grounds and bran. During pelleting, the optimal degree of wetting of the material was studied to achieve optimal yield of pellets and sufficiently strong pellets. Different ratios of substrates for pelletization were also studied and the quality of produced pellets was assessed. The content of macro and microelements in the prepared pellets was determined. Pellets have been shown to be a good source of elements important for plant growth.
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Isolation of antimicrobial compounds from spent coffee grounds
Kurzová, Pavlína ; Veselá, Mária (referee) ; Kovalčík, Adriána (advisor)
Coffee grounds are one of the very valuable lignocellulosic wastes that have been able to be processed and used for isolated phenolic substances. Many phenolic substances isolated from lignocellulosic wastes have antimicrobial properties. Aim of this thesis is isolation phenolic substances from spent coffee grounds extract and their available antimicrobial properties. Two isolation ways were applied to receive phenolic substances from spent coffee grounds: 1) solvent extraction (hexane, 75% ethanol, 70% acetone, diethyl ether, and ethyl acetate) and 2) release of active substances by alcoholic fermentation. All isolated materials were characterized by the viewpoint of concentration of reducing sugars, polyphenols and flavonoids. Subsequently, their antimicrobial activity was determined by using agar diffusion and broth dilution methods. Two gram-positive bacteria (Bacillus subtilis and Micrococcus luteus), one gram-negative bacteria (Serratia marcescens) and two yeasts (Candida glabrata and Saccharomyces cerevisiae) were used for antimicrobial testing. High-performance liquid chromatography (HPLC) was used to identify phenolic substances in the extracts. First, the results showed that the isolated sample with the highest antimicrobial activity was 70% acetone extract. This extract contained chlorogenic acid, gallic acid, caffeic acid and coumaric acid according to HPLC. The ethyl acetate extract showed the lowest antimicrobial activity. Second, after lyophilization, the isolated materials also revealed high antimicrobial activity. The highest antimicrobial activity displayed the materials obtained by the extraction with 70% ethanol. This sample contained chlorogenic acid, gallic acid and caffeic acids. Next, samples with phenolic compounds were obtained by the alcoholic fermentation of spent coffee grounds. These samples showed similarly to the previous solution extracts significant antimicrobial activity. Interestingly, the unfiltered samples received directly after alcoholic fermentation also showed antifungal properties. The characterization of phenolic compounds by HPLC showed similarly as in previous examples that chlorogenic, caffeic and gallic acids were present in these samples.
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Possibility of utilization of solid waste from spent coffee grounds rafination for agricultural purposes
Slavíková, Zuzana ; Vespalcová, Milena (referee) ; Pořízka, Jaromír (advisor)
The main focus of this diploma thesis is the utilization of spent coffee ground (SCG) and its biorefinery products in agriculture primarly as a prospective organic fertilizer. The study verifies an influence of the addition of native SCG as well as its acid hydrolysed, defatted and oxidized forms to experimental clay soil on chemical and physical properties (ph, conductivity and mineral content). Growing experiments were realized by using Lactuca sativa to detect positive or negative effects on growth. Samples of basic soil and soil with the addition of commercial NPK fertilizer served as a reference to measuring data. Measurements showed that addition of SCG and products of its biorefinery to the soil caused a decrease of pH and an increase of conductivity of soil samples. Significant increase of extractable calcium, magnesium, manganese and moderate increase of potassium content was detected. 2 % addition of SCG to soil had no impact on plants growth. The number and visual appearance of lettuces were comparable with plants in basic soil. No seed on acid hydrolysed samples germinated, which was caused by an increase of conductivity and sulphate content in these samples. In defatted and oxidized samples the early germination and the highest number of lettuces was observed. The low content of phosphorus in all soil samples had a great impact on growth rate and visual appearance of cultivated lettuces. In comparison with soil with NPK addition, lettuces in samples with SCG and its form had a pink-grey colour and lower growth.
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Hydrolytic cleavage of coffee spent ground
Skřivanová, Veronika ; Hlaváček, Viliam (referee) ; Obruča, Stanislav (advisor)
The bachelor thesis deals with various types of hydrolysis of spent coffee ground for the following biotechnological applications such as the culture medium. The work included mechanical, acid, alkaline and enzymatic hydrolysis. The resulting hydrolysates were analyzed concerning the content of reducing carbohydrates, and potentially inhibitory substances polyphenolic nature. The results show that the best conditions for culturing yeast samples were prepared with a concentration of coffee 150 g/l hydrolysed combination of 2,5% mineral acid by heating at 121 °C for 15 minutes. Using ultrasonic homogenizer significantly increases the effect of hydrolysis. The enzymatic hydrolysis is best placed hydrolyzate prepared cellulase. The hydrolysed spent coffee grounds were used as the production medium for the production of ethanol by Saccharomyces cerevisiae. For samples was determined concentration change of glucose and ethanol by HPLC/RID. The highest concentration of biomass sample contained hydrolyzed cellulose on the other side, the highest yields of ethanol (20,07 g/l) were achieve using hydrolysate prepared by 2,5% hydrochloric acid.
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Biotechnological production of polyhydroxyalkanoates using wastes of coffee production
Vašíčková, Monika ; Benešová, Pavla (referee) ; Obruča, Stanislav (advisor)
This bachelor thesis is focused on study of production of polyhydroxyalkanoates (PHA) by bacteria Burkholderia cepacia and Burkholderia sacchari. Production of PHA has been studied using spent coffee grounds hydrolysates which have been prepared by different aproaches. In the thesis is compared standard method of coffee ground hydrolysis by mineral acid followed by enzymatic hydrolysis. Hydrolysates which have been produced were analyzed in terms of concentration of saccharides and efficiency of hydrolysis. The best producer of PHA (based on results) was bacterium Burkholderia cepacia, in the medium which has been prepared by hydrolysis of spent coffee grounds extracted by 60% solution of ethanol. Biomass yield of this cultivation was 3,553 g/l with 32,472% PHA content. This PHA contained 6,09% 3-hydroxyvalerate. In the other experiment, we verified alternative hydrolysis of spent coffee grounds – by commercially available enzymes. We used cellulase, hemicellulase and the enzymatic cocktail which has been produced by mould. Hemicellulase was the most effective hydrolytic enzyme and its application resulted in production of the highest amount of biomass – 5,708 g/l. In this cultivation, only homopolymer PHB has been which is probably caused by the fact, that during the enzymatic hydrolysis levulinic acid or any other potential precursor of 3HV is formed.
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