380 results about "Hepg2 cells" patented technology

The invention discloses a process of knocking out Wnt3a gene and a verification method thereof. The knockout and verification of Wnt3a gene are finished through the following steps: establishment of a Cas9 lentiviral vector for Wnt3a gene, culture and passage of HepG2 cell, lentivirus infection and screening of target cell, verification of gene knockout efficiency through a mispairing enzyme method, cell protein analysis and cell proliferation detection by a CCK-8 method. The invention has the following advantages: the Wnt3a gene is knocked out by establishing a Cas9 double-vector lentivirus system for the first time; Crispr / Cas9 is a technology for accurately editing specific site of the genome of any species, and the cell-level single gene or multiple genes can be knocked out by the technology; compared with other gene editing technologies, the method has the advantages that the targeting accuracy is higher; only if the RNA target sequence is completely matched with the genome sequence, can the Cas9 cut the DNA and realize simultaneous knockout of multiple sites of the target gene; and moreover, the experimental period of vector establishment is short, the time and the cost are remarkably saved, and species limit is avoided.

The present invention provides novel synthetic apolipoprotein E (ApoE)-mimicking peptides wherein the receptor binding domain of apolipoprotein E is covalently linked to 18A, the well characterized lipid-associating model class A amphipathic helical peptide, or a modified version thereof. Such peptides enhance low density lipoprotein (LDL) and very low density lipoprotein (VLDL) binding to and degradation by fibroblast or HepG2 cells. Also provided are possible applications of the synthetic peptides in lowering human plasma LDL / VLDL cholesterol levels, thus inhibiting atherosclerosis. The present invention also relates to synthetic peptides that can improve HDL function and / or exert anti-inflammatory properties.

The invention discloses a polypeptide specifically combined with a HepG2 cell surface. According to the invention, four polypeptide segments are selected by utilizing a phage display random dodecapeptide library, the amino acid sequences of the four polypeptide segments are respectively LLADTTHHRPWT, LLADTPHHRPWT, FGWVTPHHELRS and SLSDLTHMGPWP. According to the invention, a polypeptide sequence combined with a liver cancer HepG2 cell is selected by utilizing a phage polypeptide display technology, and ELISA (enzyme-linked immunosorbent assay) identifies the affinity of phage clone and the liver caner cell, thus eight phage clones are obtained; four polypeptide sequences are obtained by sequencing, wherein the common amino acid sequence (basic sequence) is ***D(V)TT(P)HH*P(L)W(R)*; homology analysis indicates that the basic sequence of the polypeptide is possibly amino acid determinant on a ligand protein combined with a tumor cell surface receptor; cell immunofluorescence further identities that the target result of the positive clone of the phage prompts that the positive clone of the phage can be specifically combined with the HepG2 cell; and the selected specific polypeptide of the liver cancer HepG2 cell provides an experiment basis for early diagnosis of liver cancer, targeting delivery of an antitumor medicine and research and development of a targeting short peptide medicine.

The invention relates to an Ursolic Acid (UA) derivative. The Ursolic Acid (UA) derivative is a NO-donating UA derivative formed by coupling ester bonds or amido bonds of Ursolic Acid (UA) which has anti-tumor activity with NO donators in different types by connecting groups; and external primary screening result shows that the toxic effect of a plurality of compounds on HepG2 is evidently stronger than UA, therefore, the Ursolic Acid (UA) derivative has the prospect of anti-tumor application.

The invention relates to antiGPC3-PB NPs (antiglypican3-Prussian Blue Nanoparticles) for photothermal therapy and magnetic resonance imaging of liver cancer as well as preparation and an application thereof. The antiGPC3-PB NPs consist of cores of PB NPs formed by taking citric acid as a surface protectant and a GPC3 antibody which is in covalent coupling through EDC / NHS on the surface. The antiGPC3-PB NPs provided by the invention have a good target recognition function to hepatoma carcinoma cells HepG2 and effectively enter the cells. Meanwhile, the antiGPC3-PB NPs have an excellent photothermal killing function to the HepG2 cells and can be used for photothermal therapy of hepatoma carcinoma cells. The antiGPC3-PB NPs have a good nuclear magnetic resonance contrast imaging function and have a potential of becoming a new generation of a target magnetic resonance imaging contrast agent.

The invention discloses an erlotinib derivative with antitumor activity, and a preparation method and application thereof, and belongs to the technical field of synthesis of antitumor active medicine. The method has the main technical scheme that the erlotinib derivative with antitumor activity has a structure formula shown as the accompanying drawing, wherein R is phenyl, p-methylphenyl, m-nitrophenyl, o-chlorphenyl or o-hydroxy benzon phenyl. The invention also discloses a concrete synthesis process of the erlotinib derivative with antitumor activity and application of the erlotinib derivative with antitumor activity to preparation of liver cancer treatment medicine. The erlotinib molecules are modified and are structurally connected with a series of different 1,2,3-triazole groups; the synthesized erlotinib derivative is subjected to anti-tumor activity test; the test result shows that the compound has high inhibition activity on liver cancer HepG2 cells.

The invention relates to a double-signal transgenic cell sensor for screening a chemopreventive agent and an establishment method thereof. The double-signal transgenic cell sensor is provide with an antioxidant response element (ARE), a TK promoter, enhanced green fluorescent protein (EGFP) and red fluorescent protein (DsRed), wherein expression of the EGFP is regulated and controlled by the ARE. The establishment method comprises the following steps: firstly establishing a eukaryotic reporter vector which is started by the TK promoter and regulated and controlled by four ARE repetitive sequences at upstream; inserting the DsRed and promoter fragments thereof into the vector to establish a double-signal reporter vector; and transfecting the reporter carrier with an HepG2 cell to obtain a transgenic cell, namely, the double-signal transgenic cell sensor of the invention. The established double-signal transgenic cell sensor of the invention which takes the EGFP as a reporter gene and the DsRed as internal reference requires no any substrate and auxiliary reagent, is safe and has convenient operation, short time, low expense and no environmental pollution.

The invention provides the application of carbon nanotube-chitosan-phycocyanin complex in the preparation of antitumor drugs. The carbon nanotube-chitosan-phycocyanin complex is composed of multi-walled carbon nanotubes, Chitosan and spirulina phycocyanin are formed by non-covalent combination. The complex has good growth inhibitory effect on breast cancer MCF-7 cells and liver cancer HepG2 cells, especially under the irradiation of near-infrared light and visible light. The inhibitory effect was further strengthened, and all showed the characteristics of killing tumor cells. As an anti-tumor biomedical material, the carbon nanotube-chitosan-phycocyanin composite provided by the invention has broad prospects in photodynamic therapy and photothermal therapy of tumor cells.

The invention discloses a myricetin derivative containing piperazine amides. The myricetin derivative containing piperazine amides is characterized in that a general formula of the myricetin derivative is as shown in the description. In the formula, R1 represents more than one hydrogen atom, methoxy, nitryl, methyl, trifluoromethyl or halogen atoms at ortho position, meta position or para position of benzene ring. The compound has certain inhibition activity on hepG2 cells and SGC7901 cells, is low in toxicity to normal cells, and can be used for preparing anti-tumor medicines.

The invention discloses a pregnane X receptor (PXR)-multidrug resistance-associated protection (MRP2) luciferase reporter gene-expressing technical platform high-flux medicament screening method, which screens candidate potential activity pilot medicaments by directly starting from a medicament metabolism dynamic target which is used in a terminal medicament clinic research stage in a new medicament research. In the method, a luciferase reporter gene containing a MRP2 gene promoter sequence and expression plasmids of RXR is constructed and human hepatocellular carcinoma (HepG 2) cells are transfected transiently; and the high-flux screening of in-vitro RXR induction potential activity pilot medicaments is carried out by detecting the activity of the luciferase in a self-luminous detector and reflecting the influences of different potential activity pilot medicaments on the activity of a MRP2 promoter according to the ratio of the fluorescence of a glowworm to the fluorescence of a sea pansy. The method can avoid severe untoward effects aroused by activity medicaments obtained by other medicament screening methods due to medicament interaction generated in a final clinical medication process, save a big amount of preliminary investment in the new medicament research and reduce blindness.

The invention relates to a method for evaluating the cytotoxicity of environmental pollutants. The method adopts a HepG2 cell as a test cell and comprises the following steps: (a) establishing a pretreatment method for extracting metabolites from a cell culture fluid rapidly; (b) analyzing the 23 metabolites in the cell culture fluid quantitatively by adopting HPLC-MS / MS (high performance liquid chromatography and mass spectrometry or mass spectrometry); (c) establishing the metabolic profile chart of the HepG2 cell; and (d) analyzing the influence of the environmental pollutants on all the metabolic pathways of the HepG2 cell successfully by adopting a metabolic flux analysis system according to data obtained by adopting the HPLC-MS / MS. The pretreatment method is simple, various metabolites in the cell culture fluid can be quantitated accurately by adopting the HPLC-MS / MS, and the influence of the environmental pollutants on the metabolic pathways of the HepG2 cell can be reflected intuitively by combining the metabolic flux analysis system. The method provided by the invention has the advantages of simple operation, short analysis time, high sensitivity, good reproducibility and the like, and comprehensive information can be obtained.

The present invention provides novel synthetic apolipoprotein E (ApoE)-mimicking peptides wherein the receptor binding domain of apolipoprotein E is covalently linked to 18A, the well characterized lipid-associating model class A amphipathic helical peptide, or a modified version thereof. Such peptides enhance low density lipoprotein (LDL) and very low density lipoprotein (VLDL) binding to and degradation by fibroblast or HepG2 cells. Also provided are possible applications of the synthetic peptides in lowering human plasma LDL / VLDL cholesterol levels, thus inhibiting atherosclerosis. The present invention also relates to synthetic peptides that can improve HDL function and / or exert anti-inflammatory properties.

The invention discloses a preparation method of sargassum oligosaccharide. The preparation method comprises the steps that fine polysaccharide obtained through degreasing and deproteinizing of sargassum is taken as a raw material, ultrasonic treatment is utilized, alginate lyase, mannase, xylanase and pectinase are sequentially added to perform enzymolysis on the polysaccharide, the polysaccharide which is not degraded fully is removed through an ethyl alcohol sedimentation method, supernate is centrifuged and screened by a molecular sieve to obtain retained matter, freeze drying is performed, and the sargassum oligosaccharide is prepared. The prepared sargassum oligosaccharide has the high inhibitory activity on alpha-glucosidase, the IC50 value is 4.82 mg / mL, the dose dependency is presented, and meanwhile the obvious promoting effect on glucose consumption of insulin-resistant HepG2 cells is achieved. According to the preparation method, the non-specific commercial enzymes are adopted, the process route is simple and reasonable, the method is suitable for industrialization, the preparation amount of the hypoglycemic active oligosaccharide is increased, and meanwhile the enzyme consumption and production cost are reduced; the method is an effective method for preparing the sargassum oligosaccharide and can be applied to hypoglycemic drugs, health care products and food.

The invention discloses a compound traditional Chinese medicine extract composition for preventing and treating diabetes, comprising a component A and a component B with the weight ratio of 1:1 which are obtained from herbal medicines of astragalus and glycyrrhiza through water decoction, ethanol precipitation, organic solvent extraction or macroporous adsorption resin separation based on an ancient traditional Chinese medicine formula of Astragalus Liuyi Soup. Proved by invitro cell glucose consumption experiments, the composition can promote the glucose consumption of HePG2 cells; proved by animal in vivo experiments, the composition has remarkable function of reducing blood glucose of a hyperglycemic rat caused by alloxan, can increase the uptake of glucose in liver cells to promote glycogen synthesis, adjusts the disorder state of blood fat and improves the pathological changes of pancreas and liver tissues.

Triptolide derivatives and application thereof relate to triptolide. Triptolide and the derivatives thereof has different-degree anticancer activity on HepG2 cell and MCF-7 cell. A method for using tRXRalpha and RXRalpha to evaluate the anticancer activity and toxic and side effects of triptolide and the derivatives thereof is firstly provided. The triptolide and the derivatives thereof are confirmed to have the anticancer activity closely related to the tRXRalpha protein expression lowering capacity, and the stronger rRXRalpha lowering capacity, the higher anticancer acitivty. Also the technical scheme firstly confirms that reduction of the toxic and side effects of the triptolide derivatives is related to the stability of normal-cell full-length RXRalpha protein, and the stronger protection effect of the derivatives on full-length RXRalpha, the smaller toxic and side effects.

The invention relates to an ursolic acid derivative chemically modified by polyethylene glycol and a preparation method of the ursolic acid derivative. In the method, a novel ursolic acid derivative with anticancer activity is developed by modifying 28 bits of carboxyl of ursolic acid with butanedioic anhydride, ethylene diamine and polyethylene glycol. As proved by a pharmacological test, the ursolic acid derivative has remarkable in-vitro suppressing capabilities on human liver cancer HepG2 cells, human stomach cancer AGS cells, human stomach cancer BGC-823 cells and human prostatic csarcinoma PC-3 cells.

The invention provides an adeno-associated virus recombinant vector for knocking out Egr3 gene, and a construction method and application thereof. The vector includes at least the following operably connected sequence elements: a 5' end inverted repetitive sequence, a CMV promoter, a sacas9 coding sequence, a polyA signal sequence, a U6 promoter sequence, a gRNA sequence and a 3' end inverted repetitive sequence. The adeno-associated virus recombinant vector can efficiently knock out Egr3. Through researches, the inventors found that the Egr3 gene knockout vector can effectively inhibit the growth of transplanted tumors and tumor angiogenesis of a HepG2 cell hepatoma model. This shows that the technical scheme of the invention can be applied to the treatment of liver cancer diseases.

The invention relates to ursolic acid derivatives with anticancer activity and a preparation method thereof. In the method, a carbonoxyl group at the C-28 position of ursolic acid is connected with natural alpha-amino acid through ethanediamine in a mode of forming an amido bond to synthesize a series of ursolic acid derivatives with anticancer activity. In-vitro pharmacological experiments indicate that the ursolic acid derivatives chemically modified by amino acid have obvious in-vitro inhibition effect on human liver cancer HepG2 cells, human colon cancer HT-29 cells, human gastric cancer AGS and BGC-823cells, and human prostatic cancer PC-3 cells.

The invention relates to an ELISA (enzyme-linked immuno sorbent assay) kit for assaying serologic preneoplastic markers of hepatitis B and hepatic cellular cancer, and an application of the kit in quickly assaying hepatic precancerous lesion. According to the kit, a hepatic precancerous lesion antibody is assayed by a solid-phase immuno assay ELISA; abnormally expressed gene segments URG4, URG7, URG11, URG12, URG19 and URG2 are cloned by suppression cDNA (complementary deoxyribonucleic acid) subtractive hybridization in positive and negative HepG2 cell lines of an X gene; a hydrophyllic end sequence is selected, artificial polypeptide is subjected to solid-phase synthesis, and the ELISA kit for assaying serologic preneoplastic markers of hepatitis B and hepatic cellular cancer is prepared by using the artificial polypeptide as an envelope antigen. The kit can be used for effectively assaying hepatic precancerous lesion, is specific in method, easy to operate, low in price, safe and non-invasive, and can be used for assaying by a simple serological method.

The invention provides abalone viscera acidic polysaccharose. According to the abalone viscera acidic polysaccharose, a main chain comprises rhamnose and glucuronic acid, wherein a C-2 position or C-3 position of the rhamnose in the main chain is subjected to sulphating; and the rhamnose in the main chain is connected with the rhamnose or galactose to form a branched chain structure. The abalone viscera acidic polysaccharose which is extracted from abalone viscera can promote the proliferation of hepatoma carcinoma cells (HepG2) in vitro obviously, and has a certain effect of dose dependency; and experiments of studying a repair effect of the abalone viscera acidic polysaccharose on the HepG2 cells which are subjected to oxidative damage and on rat hepatic tissues which are subjected to acute hepatic damage caused by carbon tetrachloride in vivo indicate that the abalone viscera acidic polysaccharose can be used as a functional factor for protecting liver.

The invention discloses a cyclopeptide compound clavatustide A as well as a producing strain, a preparation method and an application thereof. The structural formula of clavatustide A is represented as formula (I): the preparation method comprises steps as follows: activated aspergillus clavatus CCTCC No. M2013421 is inoculated into a fermentation culture solution for fermentation culture; after fermentation is finished, a mycelium and fermentation broth are obtained through separation; a mycelium extract or a fermentation broth extract is subjected to chromatographic separation and purification treatment, and the cyclopeptide compound is prepared; and the application relates to an application of the cyclopeptide compound in preparation of antineoplastic drugs or cancer prevention health food. The cyclopeptide compound has better antitumor activity in vitro, the IC50 value of the cyclopeptide compound to hepG2 cells is 15 mu g / mL, and the cyclopeptide compound has an excellent development prospect; and the preparation method is simple and convenient to operate and suitable for large-scale production.

The invention discloses application of mauremys mutica polypeptide mixtures to the field of preparation of fatty liver prevention and treatment healthcare products or fatty liver prevention and treatment medicines, a fatty liver prevention and treatment healthcare product or a fatty liver prevention and treatment medicine with the mauremys mutica polypeptide mixtures. The application, the fatty liver prevention and treatment healthcare product or the fatty liver prevention and treatment medicine have the advantages that the mauremys mutica polypeptide mixtures have excellent liver healthcare functions; as verified by fatty liver model tests implemented by HepG2 cells induced by different inducers, the contents of TG (triglyceride) and LDL-C (low-density lipoprotein-cholesterol) in the HepG2 fatty liver cells induced by the different inducers including oleic acid, glucose and alcohol can be effectively reduced by the mauremys mutica polypeptide mixtures, the content of lipid in fatty livers of the HepG2 cells induced by the different inducers including the oleic acid, the glucose and the alcohol can be obviously reduced by the mauremys mutica polypeptide mixtures and oil red O staining mauremys mutica polypeptide mixtures which are combined with one another, and accordingly the mauremys mutica polypeptide mixtures have excellent application prospects in the field of preparation of the fatty liver prevention and treatment healthcare products or the fatty liver prevention and treatment medicines.

The invention discloses a synthesis method for TB derivatives with human liver cancer HepG2 cell resisting activity, belonging to a synthesis method for TB derivatives. The synthesis method comprises the steps of carrying out aldol condensation reaction on different formyl-substituted TB derivatives and o-acetylphenol compounds to obtain TB-chalcone compounds; and carrying out condensation reaction on different formyl-substituted TB derivatives and diaminobenzene under the catalysis of silicon sulfoacid (SSA) to obtain TB-benzimidazole compounds, and controlling different reaction conditions by taking the TB-chalcone compounds as raw materials to obtain a series of TB-flavonoid compounds. The activities of two different types of TB derivatives resisting a human liver cancer HepG2 cell are primarily researched, and six products with favorable human liver cancer HepG2 cell resisting activity is screened, so that the basis is laid for developing the TB derivatives into novel anti-cancer drugs. The synthesis method has the advantages of relatively high reaction yield, mild reaction condition, simplicity in operation, very short reaction time, high yield, simplicity and convenience in aftertreatment, environment-friendly reaction, high economic efficiency, high efficiency and extremely high actual application value.

The invention discloses gynostemma pentaphyllum extract compounds (I) with inhibiting actions on human liver cancer HepG2 cells and a preparation method thereof, and application of the compounds in medicine, belonging to the field of phytochemistry. The preparation method of the compounds disclosed as Formula (I) comprises the following steps: carrying out high-temperature high-pressure treatment on whole gynostemma pentaphyllum, extracting with ethanol under reflux, and concentrating the extracting solution under reduced pressure to obtain an extractum; adding distilled water into the extractum to form a suspensoid, and extracting sequentially with dichloromethane and ethyl acetate; concentrating under reduced pressure to obtain an ethyl acetate extract; passing the extract through an HP20 resin, eluting sequentially with 20%, 50% and 70% ethanol, and concentrating the 70% ethanol eluate under reduced pressure to obtain an elution product; and treating the elution product with silica gel column chromatography, eluting with dichloromethane / methanol in a ratio of 20:1-10:1 (v / v), sectionally collecting the eluates to obtain 6 components, and eluting the component 3 with acetonitrile / water in a ratio of 53:47 (v / v) at the flow rate of 3 mL / minute in a semipreparative chromatographic column (250*10mm, 5 mu m). The pharmacodynamical test indicates that the compounds disclosed as Formula (I) have obvious activities for inhibiting cancer cell proliferation.

The invention discloses a biodegradable water-soluble polycarbonate and a method for preparing the same. The polycarbonate is poly (dihydroxyl ethyl methylamine carbonate) which is a homopolymer having the number-average molecular weight of between 1,000 and 12,000 and a structural formula being the molecular formula. The method comprises the following steps: using 6,14-dimethyl-1,3,9,11-tetraoxy-6,14-diaza-cyclo-16-oxane-2,10-dione as a monomer and Novozym435 as a catalyst which are added to a reaction container according to a ratio of 1:0.01-0.20:0.1-10 g / g / ml to toluene, sealing the reaction container to react at a temperature of between 60 and 90 DEG C for 12 to 48 hours; and after the reaction, dissolving the reaction product by using a small amount of CH2Cl2 or chloroform or toluene, filtering the product, fully precipitating the product with large amount of poor solvent, collecting and drying the precipitation to obtain the biodegradable water-soluble polycarbonate. The polycarbonate is soluble in water, has small biological toxicity in HeLa and HepG2 cell lines, and has high biocompatibility, simple preparation method and high material security.

The present invention provides pyrrolo[2,1-c][1,4]benzodiazepine-glycoside prodrug of general formula 1a-b, useful as selective anticancer agents. The present invention also provides a process for the preparation of pyrrolo[2,1-c][1,4]benzodiazepine-glycoside prodrugs of general formula 1a-b. This invention also provides activation of these prodrugs by E.coli β galactosidase and envisaged that these molecules are toxic to human cancer cell lines in the presence of the enzyme E.coli β-galactosidase. The prodrugs 1a and 1b were also found to be toxic to human cancer HepG2 cells even in the absence of the E.coli β-galactosidase. The toxic effect of the molecules when activated was similar to that of the parent molecules 6a and 6b, respectively.

The invention relates to a herba epimedii total flavonoid enzymatic product. Herba epimedii total flavonoid is generated through immobilized helicase, and the enzymatic product has higher antineoplastic activity than the herba epimedii total flavonoid archetype and free enzyme enzymatic product and has high oral absorptivity. The invention further discloses a preparing method of the enzymatic product. The immobilized enzyme is used for enzymolysis of herba epimedii total flavonoid, selected helicase is high in combining efficiency with a fixed carrier and high in stability, the enzymolysis conversion rate is large, the immobilized enzyme can be used circularly, resources can be saved, and green production is achieved. The invention further relates to application of the enzymatic product in antitumous effect, and the herba epimedii total flavonoid enzymatic product obtained through the technical scheme has a remarkable anti-proliferative effect on the human lung cancer cell A549, liver cancer HepG2 cell, breast cancer MCF-7 cell, cervical cancer Hela cell and can be used for treating the lung cancer, liver cancer, breast cancer and cervical cancer.

The invention discloses exopolysaccharide-producing pediococcus pentosaceus and application thereof, and belongs to the field of microbes. The pediococcus pentosaceus provided by the invention has been preserved in CGMCC (China General Microbiological Culture Collection Center) from December 11, 2015, and a preservation number is CGMCC No:11857. A strain has the advantages that high yield of the exopolysaccharide can be realized; the exopolysaccharide yield is 153.60 mg / L. The strain has high resistant capability on NaCl, cholate and gastrointestinal fluid, and has high adhesion capability on Caco-2 cells; in addition, the oxidation resistance capability on HepG2 cells in an oxidation stress state is improved; the pediococcus pentosaceus can be used as probiotics or oxidation resistance products to be used in the fields of food, medicine, cosmetics and the like.

The invention discloses a Pleurotus citrinopileatus protein extractive and an application thereof in tumor resisting and particularly relates to the application of the Pleurotus citrinopileatus protein extractive in preparation of anti-tumor products or anti-tumor cell products. The Pleurotus citrinopileatus protein extractive is prepared by a method including the following steps of: (1) carrying out lixiviating by utilizing water after crushing Pleurotus citrinopileatus sporocarp, collecting water-soluble matters, so as to obtain Pleurotus citrinopileatus water-soluble extractives; and (2) carrying out ammonium sulfate precipitation with the saturability of 80% on the Pleurotus citrinopileatus water-soluble extractives, collecting precipitates, and obtaining the Pleurotus citrinopileatus protein extractive after carrying out deionized water dialysis on the precipitates. After the Pleurotus citrinopileatus protein extractive is used for processing human liver cancer HepG cells, human breast cancer MCF-7 cells and human lung cancer A-549 cells for 72 hours, IC50 (half maximal inhibitory concentration) values respectively are 1.0 microgrammes per milliliter, 0.45 microgrammes per milliliter and 1.15 microgrammes per milliliter, and inhibition ratios are increased along the prolonging of the time and the increasing of the concentrations.