Fresh Substrates Research Articles

Evaluating C sources and microbial biomass dynamics involved in the triggering response with soil depth

The triggering response has attracted much research interest. However, the main C source of triggered CO2–C and the dynamics of soil microbial biomass C (biomass C) and adenosine 5′-triphosphate (ATP) concentrations during the triggering response still remain largely unknown. We labeled the soil microbial biomass of three soil layers (0–10 cm, 10–30 cm and 30–60 cm) of a forest soil with dried aboveground maize (22 atom%, 2.5 mg g−1 soil) and glucose (22 atom%, 2.5 mg g−1 soil) to determine the contribution of the four potential C sources involved in the triggering response: 13C-labeled maize and glucose, biomass C, soil organic carbon (SOC), and triggering glucose. After 56 days of soil pre-incubation, the 13C abundances of biomass C and SOC were 5.27–6.71 and 1.94–2.82 atom%, respectively. Addition of 10 μg glucose-C g−1 soil caused a strong and rapid triggering response resulting in 2.3–6 times more triggered CO2–C evolved than was contained in the triggering glucose, which increased with soil depth. The atom% 13C–CO2 values of model calculations were closest to measured values when assumed to derive completely from biomass C. Biomass C did not significantly change at day 1 but significantly decreased by 7.1–27.6% at day 5. ATP concentrations (nmol ATP g−1 soil) increased from 6.2-10.8% by day 1 to 9.2- 28% by day 5 (p < 0.05). Soil biomass C and ATP contents reached values similar to those of the control after 10 days. These results indicate that the CO2–C from the triggering response mainly derived from mineralization of biomass C during the early triggering stage and from mineralization of residual substrates thereafter. Biomass ATP concentrations (μmol ATP g−1 biomass C) remained constant during the later stages. We conclude that the triggering response is mainly due to the rapid activation of soil microorganisms through mineralization of biomass C. Microorganisms that adopt this survival strategy, may have a rapid reaction in the utilization of fresh substrates.

Rehabilitation of saline soil with biogas digestate, humic acid, calcium humate and their amalgamations

ABSTRACT Amelioration of saline soil is a requisite in order to increase crop productivity. A soil incubation study was performed for 60 days using digestate, humic acid, calcium humate and their combinations to investigate the influence on physical, chemical, microbial and enzyme activities of saline soil. Overall, digestate combined with calcium humate followed by humic acid treatments have shown their potency in decreasing the soil pH, electrical conductivity (EC), and sodium ion (Na+) concentration, and increase in potassium ion (K +), calcium ion (Ca 2+), magnesium ion (Mg 2+), mean weight diameter (MWD), soil enzyme activities, microbial biomass carbon (MBC), MBC: microbial biomass nitrogen (MBN) and soil respiration than control. The digestate, humic acid individually and their amalgamation evidenced greater MBN among all the treatments. The digestate alone efficiently improved the soil properties than humic acid and calcium humate individual groups except for the MWD where it is pronounced more in the latter groups. The greater metabolic quotient (qCO2) was observed in control than organic matter amended treatments indicating the stress conditions. The increase in water-extractable organic matter (WEOM) with minimal aromaticity (specific ultraviolet absorbance at 254 nm-Suva 254) in integrated amendments comprising groups, laid the ground reason to improve the properties of saline soil. Therefore, this study concludes that the fusion of fresh and humified substrates could facilitate reclamation.

Using highly recyclable sodium caseinate to enhance lignocellulosic hydrolysis and cellulase recovery

Most additives that capable of enhancing enzymatic hydrolysis of lignocellulose are petroleum-based, which are not easy to recycle with poor biodegradability. In this work, highly recyclable and biodegradable sodium caseinate (SC) was used to enhance lignocellulosic hydrolysis with improved cellulase recyclability. When the pH decreased from 5.5 to 4.8, more than 96% SC could be precipitated from the solution and recovered. Adding SC increased enzymatic digestibility of dilute acid pretreated eucalyptus (Eu-DA) from 39.5% to 78.2% under Eu-DA loading of 10 wt% and pH = 5.5, and increase cellulase content in 72 h hydrolysate from only 15.2% of the original to 60.0%, which facilitated the recovery of cellulases through re-adsorption by fresh substrates. With multiple cycles of re-adsorption, application of SC not only increased the sugar yield of Eu-DA by 95.5%, but also reduced cellulase loading by 40%.

Study on the chemical modification of alkali lignin towards for cellulase adsorbent application

The research of cost-efficient lignin-based adsorbents is a practical strategy for the recovery of cellulase. In this study, alkali lignin was modified to increase the phenolic hydroxyl (Ph-OH) content for cellulase adsorption applications. After phenolation, compared with the lignin reference, the maximum adsorption cellulase capacity of lignoresorcinol (LigR) and lignopyrogallol (LigP) was improved from 76.5 mg/g to 842.1 mg/g and 911.4 mg/g, respectively. The enzyme activity of the adsorbed cellulase on LigR was higher than that on LigP, which could migrate to the fresh substrates during enzymatic hydrolysis. The adsorbed cellulase could be easily recovered from two lignin-based adsorbents by adjusting pH. The distinct cellulase adsorption behavior of two lignin-based adsorbents was closely related to the high Ph-OH contents and low S/G ratio in phenolated lignin samples characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Heteronuclear Single Quantum Coherence-Nuclear Magnetic Resonance (HSQC-NMR).

Damage-Free Transfer of GaN-Based Light-Emitting Devices and Reuse of Sapphire Substrate

Gallium nitride (GaN) based semiconductors have been gaining worldwide attention in optoelectronics application, notably information displays and solid-state lighting. GaN light-emitting diodes (LEDs) epilayers are typically grown on sapphire substrates with metal-organic chemical vapor deposition (MOCVD) technique due to the absence of native nitride substrates. In this paper, the mesh-patterned sapphire substrates are fabricated to speed up the laser lift-off efficiency for the separation of GaN films from sapphire substrates. Damage-free GaN thin films fabricated on the sapphire substrates were successfully released and transferred onto Si substrates with sufficient quality through a Ti/Pt/Au/In bonding and subsequent laser lift-off processes. The GaN film mounted on Si substrates exhibits almost no attenuation in PL intensity before and after its transfer. The released sapphire substrate can be reprocessed by annealing & chemical mechanical polishing (CMP) process for reuse as epitaxial substrate with considerable cost reduction, featuring a comparable photoluminescence performance with fresh sapphire substrates.

Effects of Tetracycline on Microbial Communities and Antibiotic Resistance Genes of Vermicompost from Dewatered Sludge

The high content of tetracycline in municipal sludge may result in vermicomposting products carrying a high abundance of antibiotic resistance genes, thus lowering the utilization value of the vermicompost. Hence, this study aimed to reveal the underlying effects of tetracycline concentrations on the resistance genes involved in vermicomposting systems for sludge recycling. For this purpose, fresh sludge substrates with different concentrations of tetracycline (100, 500, and 1000 mg·kg-1) were vermicomposted for 60 days using Eisenia foetida. In parallel, sludge treatment without the addition of the tetracycline was used as a control. During the experiment, changes in bacterial communities, tetracycline resistance genes (tetC, tetG, tetM, tetW, and tetX), and class 1 integron (intI1) were detected using high-throughput sequencing and qualitative PCR, respectively. The results showed that the addition of tetracycline reduced the abundance of Proteobacteria but increased the abundance of Bacteroidetes in the sludge vermicompost. Furthermore, the concentrations of tetracycline had a significant negative correlation with Shannon and Pielou indexes of bacterial diversity. In addition, tetracycline increased intI1 genes and tetracycline resistance genes in the sludge by 4.25 times and 4.7-186.9 times, respectively. Moreover, there was a significantly positive correlation between the abundance of tetM genes and tetracycline concentration. This study suggests that higher concentration of tetracycline in sludge can modify the microbial community structure of vermicompost, enhancing the abundance of antibiotic resistance genes and their associated dissemination risks.

Rhizosphere carbon supply accelerates soil organic matter decomposition in the presence of fresh organic substrates

Background and aimsBelowground C supply from plant roots may accelerate the decomposition of SOM through the rhizosphere priming effect, but the detailed interaction between substrate quality and rhizosphere C supply is poorly understood. We hypothesize that decomposition of organic matter is enhanced by the combined effect of assimilate C supply to the rhizosphere and substrate amendments.MethodsBirch trees (Betula pendula) planted in experimental mesocosms; half of these trees were shaded to reduce the supply of assimilate C to roots and ECM fungi. Either 13C-enriched glucose, straw, fungal necromass or C4 biochar were subsequently added to each mesocosm. CO2 efflux derived from substrates were separated from that derived from native SOM and roots based on the isotopic composition of total respired CO2.ResultsThe addition of all substrates increased fluxes in both un-shaded and shaded treatments, with greatest total CO2 efflux observed in soils amended with straw. Increases in un-labelled CO2 were observed to be greater in the presence of belowground C supply than in mesocosms with shaded trees.ConclusionsTurnover of SOM is closely linked to belowground C allocation. The biochemical quality and recalcitrance of litter entering the soil C pool is of critical importance to this priming, as is the interaction with rhizosphere-associated decomposition activity.

Rising bubbles enhance the gelatinous nature of the air–sea interface

AbstractBubbles rising through the water column are known to scavenge organic material and microorganisms, and transport them through the air–sea interface after bursting. This mechanism has important implications for air–sea exchange processes. However, little is known about how bubbles influence the chemical and biological properties of the sea‐surface microlayer (SML), a gelatinous film at the air–sea interface. We used floating mesocosms in the coastal Baltic Sea and a laboratory tank filled with seawater from the North Sea to study the effect of bubbling on the gelatinous nature of the SML. Bubbling was found to always increase concentrations of transparent exopolymer particles (TEP) in the SML. In the field, TEP in the SML already increased after 2 min (53% ± 63%) and 10 min (19% ± 12%) bubbling, respectively. During the tank experiment, TEP enriched in the SML by 312% (± 244%) after &gt; 3 h of bubbling. Therefore, bubbling is a highly efficient mechanism for TEP enrichment in the SML. Bubbling caused enrichment and depletion of microbial abundances (prokaryotes, flagellates, eukaryotes) in the SML. However, the incorporation of 3H‐thymidine (i.e., bacterial carbon production) was consistently stimulated after 10 min of bubbling in the field experiment, indicating a bubble‐induced import of unstressed bacteria and fresh organic substrates into the SML. Overall, our results suggest that the gelatinous matrix of the SML is re‐formed within min after disruption by bursting bubbles, and, thus, highlights the importance of biogeochemical interactions within the air–sea interface.

Potentials of animal, crop and agri-food wastes for the production of fly larvae

Fly larvae, in particular those of house fly (Musca domestica) and black soldier fly (Hermetia illucens), are increasingly considered for animal feed worldwide. A simple way to produce fly larvae is to expose suitable substrates to attract adult flies that will lay eggs in the substrates from where larvae will be subsequently extracted. This study aims to evaluate the potential of animal manures and agri-food wastes for maggot production and to identify the fly species developing in the substrates. Experiments were conducted in the Republic of Benin. Twenty-six substrates were left uncovered for 10 hours and maggots were harvested after four days. Fresh substrates were then added to residual substrates and left uncovered for another 10 hours for another production cycle. In total, three production cycles were monitored. In the first cycle, nearly 100% of the flies were house flies but black soldier flies appeared in the following cycles. The result showed that crop and agri-food substrates produced more larvae than manures. The highest yield at the first production cycle was obtained with the mixture of soybean bran and maize grain pericarp. Maize bran, pig manure and chicken manure also showed potential for maggot production. Other substrates such as cow and sheep/goat manure produced nearly no maggot when used alone but the amount of larvae substantially increased when attractants such as chicken offal were added, or when mixed with pig and chicken manure. Production decreased with the production cycles for the majority of substrates, except for mixtures based on spent grain and pineapple grain, which produced a large amount of larva at the second harvest. The activity of maggots led to temperature elevation and reduction of substrate biomass. This study showed that several substrates, in particular soybean bran, maize bran, pig manure and chicken manure show potential for maggot production.

Co-composted hydrochar substrates as growing media for horticultural crops

Hydrothermal carbonization (HTC) is a thermo-chemical process, which converts biomass into a coal-like product, referred to as hydrochar. Hydrochars have low pH and salinity, a high water holding capacity and cation exchange capacity, and thus are correlated to the requirements of horticultural substrates. However, germination- and growth-inhibiting effects were frequently observed in experiments using untreated fresh hydrochars. In this study we investigated the suitability of biological pretreated co-composted hydrochar substrates as growing media for horticultural crops. Hydrochars made from residue feedstocks, such as beer draff and green cuttings, were used to perform seed germination experiments with Chinese cabbage (Brassica rapa ssp. Pekinensis) on fresh, untreated and pretreated hydrochar-compost substrates and ii) pretreated hydrochar-compost substrates in a) different mixing ratios (10, 30 and 50% hydrochar), and b) using different hydrochars in a fixed mixing ratio of 50:50. Moreover, growth experiments with French marigold (Tagetes patula) for a growing season on the co-composted hydrochar substrates were performed. As reference substrates, a peat-based gardening substrate and a compost were used. Germination rate and plant growth were higher for co-composted substrates than on untreated freshly mixed substrates. Growth of French marigold increased with the amount of hydrochar in the mixtures up to equal growth quality compared to a peat-based gardening substrate. Substrate properties including salinity, density and pH value influenced the plant growth as well. The type of hydrochar had only a slight influence.

Ethanol production from sugarcane bagasse by fed‐batch simultaneous saccharification and fermentation at high solids loading

AbstractTo make the bioethanol conversion process economically viable, improving solids loading (&gt;15% [w/v]) in different unit operations is crucial. In this study, alkali pretreatment of sugarcane bagasse was carried out at high solids loading. Temperature and pH were optimised via batch simultaneous saccharification and fermentation (SSF) experiments using Saccharomyces cerevisiae Y‐2034 or Kluyveromyces marxianus NCYC‐587. The effects of enzyme addition mode and solids loading on ethanol production were studied in fed‐batch SSF experiments. It was demonstrated that the optimised pH and temperature for both S. cerevisiae Y‐2034 and K. marxianus NCYC‐587 were 5.2 and 37°C. The mode of enzyme addition “one‐time dose” improved ethanol productivity better than the “batch addition” mode. With fresh substrates added, solids loading strongly increased from 19% to 33% (w/v), corresponded to a small decline in the ethanol yield. At the final solids loading of 33% (w/v), the highest ethanol concentration of 75.57 ± 2.14 g/L was obtained, with ethanol productivity of 0.63 ± 0.02 g/(L h) and a yield of 66.17 ± 1.87%.

Phosphate Leaching from Green Roof Substrates—Can Green Roofs Pollute Urban Water Bodies?

Green roofs are an effective stormwater measure due to high water retention capacity and the ability of delaying stormwater runoff. However, low importance is still given to the pollutant leaching potential of substrates used in green roof construction. The aim of the study is to estimate the concentrations and loads of P-PO43− in runoff from extensive and intensive substrates. To achieve this goal, several commonly-used fresh substrates were analyzed for P-PO43− leaching potential in different scale experiments, from laboratory batch tests, leaching column experiments, and long-term monitoring of open air green roof containers. The results of the study confirmed that fresh green roof substrates contain phosphorus in significant amounts of 17–145 mg∙P-PO43−/kg and, thus, can contribute to eutrophication of freshwater ecosystems. High correlation between phosphate content estimated by HCl extraction and cumulative load in leachate tests suggests that the batch HCl extraction test can be recommended for the comparison and selection of substrates with low potential P leaching. Volume-weighted mean concentrations and UALs of P-PO43− leaching from fresh substrates were higher in cases of intensive substrates, but there was no clear relationship between substrate type and the observed P-PO43− concentration range. To avoid increasing eutrophication of urban receivers the implementation of P reduction measures is strongly recommended.

Effect of Contrasting Trophic Conditions on the Priming Effect in Gray Forest Soils

Priming effects initiated by the addition of 14С glucose have been compared for humus horizons of soils existing under continuous input of fresh organic substrates and for buried soil horizons, in which entering of organic matter has been essentially limited. The effect of microrelief on the manifestation of priming effect in the humus horizons of gray forest soil on microhigh and in microlow has been estimated. Humus horizon in soils on microhigh, not activated by glucose, produced two times more СО2 in comparison with soils of microlow. However, the introduction of glucose canceled the effect of microrelief on СО2 emission. The intensity of absolute priming effect correlated with the Сorg pool, initial microbial biomass, and enzyme activity, decreasing from humus horizons to the buried ones, and did not depend on microrelief. The effect of microrelief was observed, when assessing the priming effect relative to control (soil not activated by glucose): the value of relative priming effect was 1.5 times greater in А horizon of gray forest soil in microlow in comparison with that on microhigh being the result of increasing activity of enzymes.

Repair bond strength of nanohybrid composite resins with a universal adhesive

Objective: To investigate the repair bond strength of fresh and aged nanohybrid and hybrid composite resins using a universal adhesive (UA).Materials and methods: Fresh and aged substrates were prepared using two nanohybrid (Venus Pearl, Heraus Kulzer; Filtek Supreme XTE, 3 M ESPE) and one hybrid (Z100, 3 M ESPE) composite resin, and randomly assigned to different surface treatments: (1) no treatment (control), (2) surface roughening with 320-grit (SR), (3) SR + UA (iBOND, Heraus Kulzer), (4) SR + Silane (Signum, Ceramic Bond I, Heraeus Kulzer) + UA, (5) SR + Sandblasting (CoJet, 3 M ESPE) + Silane + UA. After surface treatment, fresh composite resin was added to the substrates at 2 mm layer increments to a height of 5 mm, and light cured. Restored specimens were water-stored for 24 h and sectioned to obtain 1.0 × 1.0 mm beams (n = 12), and were either water-stored for 24 h at 37 °C, or water-stored for 24 h, and then thermocycled for 6000 cycles before microtensile bond strength (µTBS) testing. Data were analyzed with ANOVA and Tukey’s HSD tests (p = .05).Results: Combined treatment of SR, sandblasting, silane and UA provided repair bond strength values comparable to the cohesive strength of each tested resin material (p < .05). Thermocycling significantly reduced the cohesive strength of the composite resins upto 65% (p < .05). Repair bond strengths of UA-treated groups were more stable under thermocycling.Conclusions: Universal adhesive application is a reliable method for composite repair. Sandblasting and silane application slightly increases the repair strength for all substrate types.

Winter ecology of a subalpine grassland: Effects of snow removal on soil respiration, microbial structure and function

Seasonal snow cover provides essential insulation for mountain ecosystems, but expected changes in precipitation patterns and snow cover duration due to global warming can influence the activity of soil microbial communities. In turn, these changes have the potential to create new dynamics of soil organic matter cycling. To assess the effects of experimental snow removal and advanced spring conditions on soil carbon (C) and nitrogen (N) dynamics, and on the biomass and structure of soil microbial communities, we performed an in situ study in a subalpine grassland in the Austrian Alps, in conjunction with soil incubations under controlled conditions. We found substantial winter C-mineralisation and high accumulation of inorganic and organic N in the topsoil, peaking at snowmelt. Soil microbial biomass doubled under the snow, paralleled by a fivefold increase in its C:N ratio, but no apparent change in its bacteria-dominated community structure. Snow removal led to a series of mild freeze-thaw cycles, which had minor effects on in situ soil CO2 production and N mineralisation. Incubated soil under advanced spring conditions, however, revealed an impaired microbial metabolism shortly after snow removal, characterised by a limited capacity for C-mineralisation of both fresh plant-derived substrates and existing soil organic matter (SOM), leading to reduced priming effects. This effect was transient and the observed recovery in microbial respiration and SOM priming towards the end of the winter season indicated microbial resilience to short-lived freeze-thaw disturbance under field conditions. Bacteria showed a higher potential for uptake of plant-derived C substrates during this recovery phase. The observed temporary loss in microbial C-mineralisation capacity and the promotion of bacteria over fungi can likely impede winter SOM cycling in mountain grasslands under recurrent winter climate change events, with plausible implications for soil nutrient availability and plant-soil interactions.

Chemical composition and methane potential of commercial food wastes

There is increasing interest in anaerobic digestion in the U.S. However, there is little information on the characterization of commercial food waste sources as well as the effect of waste particle size on methane yield. The objective of this research was to characterize four commercial food waste sources: (1) university dining hall waste, (2) waste resulting from prepared foods and leftover produce at a grocery store, (3) food waste from a hotel and convention center, and (4) food preparation waste from a restaurant. Each sample was tested in triplicate 8L batch anaerobic digesters after shredding and after shredding plus grinding. Average methane yields for the university dining, grocery store, hotel, and restaurant wastes were 363, 427, 492, and 403mL/dry g, respectively. Starch exhibited the most complete consumption and particle size did not significantly affect methane yields for any of the tested substrates. Lipids represented 59–70% of the methane potential of the fresh substrates.

Graphene-Templated Supported Lipid Bilayer Nanochannels

The use of patterned substrates to impose geometrical restriction on the lateral mobility of molecules in supported lipid membranes has found widespread utility in studies of cell membranes. Here, we template-pattern supported lipid membranes with nanopatterned graphene. We utilize focused ion beam milling to pattern graphene on its growth substrate, then transfer the patterned graphene to fresh glass substrates for subsequent supported membrane formation. We observe that graphene functions as an excellent lateral diffusion barrier for supported lipid bilayers. Additionally, the observed diffusion dynamics of lipids in nanoscale graphene channels reveal extremely low boundary effects, a common problem with other materials. We suggest this is attributable to the ultimate thinness of graphene.

Aggregate size and glucose level affect priming sources: A three-source-partitioning study

Decomposition of soil organic matter (SOM) protected within aggregates can be accelerated via priming effect (PE) by the addition of fresh substrates. However, the knowledge of the sources of mineralization and PE in aggregate size classes is absent. We applied the three-source-partitioning isotopic (14C + δ13C) approach to determine how aggregate size classes affect the contribution of three C sources (substrate added, recent and old SOM) to CO2 efflux and PE depending on the amount of added primer. Soil from a field with 3 years of maize cropping (C4 plants) after long-term C3 vegetation was used to differentiate between recent C (C4C; < 3 years) and old C (C3C; >3 years). Soil samples were separated into three aggregate size classes (>2 mm, 2–0.25 mm macroaggregates and <0.25 mm microaggregates) and were incubated for 49 days after being amended with two levels of 14C labeled glucose.The proportion of glucose mineralized to CO2 increased with decreasing aggregate size, but 14C incorporation into microbial biomass decreased, indicating higher C use efficiency in macroaggregates compared with microaggregates. The short-time PE was positive and was accompanied by a rapid reduction of dissolved organic C. After 49 days, the PE was higher in macro-versus microaggregates at both glucose levels. Positive PE induced by a low glucose level was observed only in large macroaggregates (>2 mm), but was observed in both macroaggregates (>0.25 mm) and microaggregates (<0.25 mm) after high glucose amendment. These results indicate that SOM pools are more decomposable in macro-versus microaggregates and that the SOM pools are involved in PE according to their biochemical availability. More primed CO2 originated from recent C4C than old C3C in larger macroaggregates under a low glucose level. The relative contribution of recent C4C to primed CO2 increased from macroaggregates (37.8%) to microaggregates (100%) after high glucose amendment. Therefore, increasing glucose addition stimulated the decomposition of old C3C in macroaggregates, but not in microaggregates. This indicates that microaggregates protect SOM against decomposition better than macroaggregates, and consequently, microaggregates can be considered as a potential reservoir for long-term C sequestration.Concluding, aggregate size is crucial for SOM decomposition, and it determines the source of PE and thus the protection of sequestrated C. The effects of the added primer on C sources involved in PE depend on the aggregate size.

American eel (Anguilla rostrata) substrate selection for daytime refuge and winter thermal sanctuary

We addressed hypotheses that anguillid eels use mud as a substrate refuge only in the absence of substrate cavities, and that the winter distribution of eels in coastal bay and estuarine habitat is limited to waters warmer than the freezing point of fish tissue (~–0.7°C). In the seasonally ice-covered southern Gulf of St Lawrence, Canada, locations of summer fyke and winter spear fisheries indicate that American eels (Anguilla rostrata) are widely distributed in both summer and winter in shallow soft-bottomed bay and estuarine habitat. Captive eels in fresh water preferred mud substrates during summer, during pre-winter cooling and during post-winter warming periods, but in winter chose mud and cobble substrates at approximately equal frequencies. Plasma antifreeze was not detected in blood sampled from eels speared in mud under winter ice. Winter bottom water temperatures in an eel wintering site were below the approximate freezing point of fish tissue 29.9% of the time. Mud of eel wintering grounds is warmer than overlying water and appears to serve as a thermal sanctuary that allows eels to safely overwinter under ice-covered waters. American eels in the southern Gulf of St Lawrence spend ~67% of their annual cycle within the substrate.

Nonlinear optical investigation of normal ovarian cells of animal and cancerous ovarian cells of human in-vitro

Laser-based study of two types of ovarian cells has been reported. For both normal and cancerous ovarian cells, growth and reproduction of cells formed to transparent and fresh substrates. Normal and cancerous cells fixed on glass substrate and nonlinear behavior of this microsize biolayer investigated by Z-scan technique using CW He–Ne laser. The magnitude and sign of nonlinear refractive index of normal and cancerous ovarian cells have been reported. Results show that nonlinear optical behavior of normal animal (Wistar rat) and cancerous human cells is different. Nonlinear refractive index (n2) of all studied normal biolayers has negative sign and vice versa for cancerous biolayers. Additionally magnitude of n2 for all samples was in order of 10−8 (cm2/w). So optical apparatus like Z-scan can be used for discriminate normal and cancerous ovarian cells and may be considered for optical diagnostic methods in medicine later.