Commercial Bleach Research Articles

Comprehensive phytochemical analysis of Salvia hispanica L. callus extracts using LC-MS/MS.

In this research, the study utilized the root, leaf, and petiole parts of in vitro grown Salvia hispanica plants as explants. Following UV-C treatment applied to developing callus, methanol extracts were obtained and analyzed using liquid chromatography-mass spectrometry (LC/MS) to investigate their anticancer properties. First, the seeds of S. hispanica were soaked in commercial bleach for 6 min to ensure surface sterilization. The most effective antimicrobial activity on Gram-negative bacteria, with a zone diameter (11 ± 0.82 mm), was noticed in callus extracts obtained from the petiole explant in the second protocol against Klebsiella pneumoniae EMCS bacteria. Anticancer activities on SH-SY5Y human neuroblastoma cells were investigated by using 1000, 500, 250, 125, 62.5, 31.25, 15.62, and 78.12 μg/mL doses of the extracts, and the most effective cytotoxic activity was determined at the 1000 μg/mL dose of the extracts obtained from both protocols. The extracts were determined to inhibit hCAI, hCAII, AChE, and BChE enzymes. The content of 53 different phytochemical components of the extracts was analyzed by liquid chromatography with tandem mass spectrometry (LC-MS/MS). Rosmarinic acid, quinic acid, and caffeic acid were found in the highest concentration. The comprehensive LC-MS/MS analysis of S. hispanica extracts revealed a diverse array of phytochemical compounds, highlighting its potential for therapeutic applications.

Influence of growth regulators on microclonal propagation of <em>Scrophularia umbrosa</em> Dumort under <em>in vitro</em> conditions

The possibility of effective microclonal propagation of Scrophularia umbrosa Dumort for producing planting materials, aimed at preservation of the species has been shown. This will aid in the creation of artificial introduction populations of this endangered species in the Republic of Tatarstan, Russia. Optimal conditions for surface sterilization of seeds, development of microshoots, in vitro rooting and acclimatization have been developed. The most effective surface sterilization and germination was achieved with 10 % commercial bleach. Nodal explants were cultured in Murashige and Skoog’s (MS) medium with different concentrations of 6-benzylaminopurine (BAP) and indole-3-acetic acid (IAA). The maximum number of microshoots was developed on MS medium containing 1.0 mg/l of BAP and 1.0 mg/l of IAA. Full strength MS medium with only IAA or together with (indole-3-butyric acid) IBA is optimal for rapid rooting of microshoots. The combination of soil: perlite (2:1) (v/v) was the best for ex vitro acclimatization of plantlets.

PHYTOCHEMICAL PROFILING of VOLATILE COMPONENTS of Echinacea purpurea (L.) MOENCH MULTIPLIED by MICROPROPAGATION TECHNIQUE

Echinacea purpurea (L.) Moench is a substantial herbaceous perennial species of ornamental and medicinal flowering plant that grows to 120 cm in maturity from the Asteraceae family and the Echinacea genus. The development of in vitro protocols for this plant can have a significant impact on the global deployment of this beneficial germplasm. It will also facilitate the rapid multiplication, biotransformation, and genetic transformation of improved phytochemical production, particularly secondary metabolites. All stages of E. purpurea micropropagation in vitro and acclimatization to in vivo conditions were investigated in this study. Furthermore, the obtained volatile components of the plants were determined in this study. The research findings revealed that the best seed sterilization was observed with 15% commercial bleach for 5 minutes. MS plant tissue culture medium including 1.25 mg L-1 6-benzyl amino purine was suitable for regeneration and the high shoot regeneration was %75 and MS medium containing 1.00 mg L-1 indole 3 butyric acid was appropriate for rooting. Furthermore, the findings show that peat is an appropriate substance for acclimation of rooted plantlets. Germacrene D, caryophyllene, Borneol, Caryophyllene oxide, and Myrtenal were identified as the main volatile components of E. purpurea by GC/MS and GC/FID analysis.

A New Protocol to Mitigate Damage to Germination Caused by Black Layers in Maize (Zea mays L.) Seeds

Maize seeds harvested in the field have higher vitality than those harvested in greenhouses but have higher contamination rates in terms of fungal or bacterial infection. It is important to disinfect maize seeds before sowing because seeds are a source of infection and damage crop production. In this study, we aimed to provide an efficient seed sterilization method to manage fungal or bacterial infections of field-harvested maize seeds. The optimized sterilization protocol was set up according to the disinfectant liquid immersion time, inverting RPM (rotations per minute), number of seeds, and black layer removal. We put 20 grains of maize seeds in 100% commercial bleach disinfectant containing 4–5% NaClO and performed 20 min of inversion at 45 RPM. After standing without inverting for the next 25 min in the sterile hood, inversion at 45 RPM for another 40 min was performed. By using this protocol, microorganisms occurred at a low rate with an average of 11.7%. Moreover, it was shown that microorganisms occurred at the lowest rate (average of 0.29% of seeds) when the black layer was removed. In addition, this sterilization method did not affect the growth and development of maize plants. These results revealed that black layer removal from maize seeds is a highly efficient, easy, and inexpensive sterilization method and can be used for seeds of various maize lines.

Chemical decontamination of methamphetamine and ephedrine using household hypochlorite bleach

Hypochlorite bleach is an easily accessible, commonly used cleaning product. Methamphetamine and ephedrine hydrochloride react rapidly with 3.5 g/L (1:8 dilution of a commercial household bleach) and 21 g/L (2:1 dilution) solutions of sodium hypochlorite bleach in water, with each reaction being complete within 5 min of mixing. The major methamphetamine reaction product was identified as N-chloromethamphetamine which was reliably quantified by dechlorination using a sulfite quench prior to sample extraction and analysis by gas chromatography – mass spectrometry (GC–MS). The initial product from ephedrine was benzaldehyde, and this then formed benzoic acid as a second-generation product in the 3.5 g/L sodium hypochlorite bleach solution.N-Chloromethamphetamine was observed to persist in solution for several hours with minor formation of benzaldehyde and N-chloro-1-phenylpropan-2-imine, a proposed second-generation product from N-chloromethamphetamine, also detected. Assessment of further N-chloramine reaction products will aid in our ability to estimate exposure risks to those attempting drug remediation using hypochlorite bleach. These observed products can also be used as potential forensic markers of the use of a property for illicit activity if bleach has been used in an attempt to decontaminate the location.

Conservation and Large Scale Propagation of a Valuable Ornamental Aquatic Plant, Echinodorus argentinensis Rataj through Micropropagation

A protocol was standardized for large scale propagation through multiple shoot proliferation from the basal buds of Echinodorus argentinensis, an ornamental aquatic plant. Explants were treated for 15 minutes with commercial bleach (containing 0.825% Sodium hypochlorite as active ingredient) which was diluted with distilled water to a concentration of 15%; and were then dipped for a second in 100% ethanol to obtain axenic cultures. The axenic basal buds initiated shoot formation within a week when cultured on full strength Murashige & Skoog medium (MS medium) supplemented with 1.0 mg/l 6-Benzylaminopurine (BAP). Number of shoots produced per explant was maximum (2.5672 shoots per explant p< 0.05) on MS medium supplemented with 1.0 mg/l BAP. Shoots were elongated considerably in all the media tried for shoot multiplication and maximum elongation (2.87 cm, p< 0.05) of the in vitro developed shoots was observed on MS medium supplemented with 1.0 mg/l BAP in combination with 0.1 mg/l Naphthalene acetic acid (NAA). Root regeneration was observed on all the shoot regeneration media and the highest number of roots/shoot (3.4568 roots per shoot) was obtained on MS medium devoid of any kind of plant growth regulators. The plantlets developed in vitro were subjected to acclimatization procedure and were finally planted in the aquarium. The protocol is ready for commercialization.

Plant Growth Regulator- and Elicitor-Mediated Enhancement of Biomass and Andrographolide Production of Shoot Tip-Culture-Derived Plantlets of Andrographis paniculata (Burm.f.) Wall. (Hempedu Bumi).

Andrographis paniculata (Burm.f.) Wall. (Acanthaceae) is revered for its medicinal properties. In vitro culture of medicinal plants has assisted in improving both the quantity and quality of their yield. The current study investigated the effects of different surface sterilization treatments, plant growth regulators (PGRs), and elicitors on culture establishment and axillary shoot multiplication of A. paniculata. Subsequently, the production of andrographolide in the in vitro plantlets was evaluated using high-performance liquid chromatography (HPLC) analysis. The shoot-tip explant was successfully sterilized using 60% commercial bleach for 5 min of immersion with a 90% survival rate and 96.67% aseptic culture. The optimal PGR for shoot growth was 6-benzylaminopurine (BAP) at 17.76 µM, supplemented into Murashige and Skoog (MS) media, producing 23.57 ± 0.48 leaves, 7.33 ± 0.10 shoots, and a 3.06 ± 0.02 cm length of shoots. Subsequently, MS medium supplemented with 5 mg/L chitosan produced 26.07 ± 0.14 leaves, 8.33 ± 0.07 shoots, and a 3.63 ± 0.02 cm length of shoots. The highest andrographolide content was obtained using the plantlets harvested from 5 mg/L chitosan with 2463.03 ± 0.398 µg/mL compared to the control (without elicitation) with 256.73 ± 0.341 µg/mL (859.39% increase). The results imply that the protocol for the shoot-tip culture of A. paniculata was developed, and that elicitation enhanced the herbage yield and the production of andrographolide.

First Report of Neofusicoccum australe Causing Branch Dieback of English Walnut cv. Chandler in Central Chile.

The English walnut (Juglans regia L.) is the second most important fruit crop of importance in Chile, with 43,700 hectares mainly in the Central Valley (www.odepa.cl, 2022). For several seasons symptoms of a branch dieback have been observed in walnut orchards with 3 to 50% of trees incidence levels. During the 2020 winter season (July) a total of 150 symptomatic spurs of 15 trees were sampled from an 8-year-old walnut cv. Chandler orchard located in Buin (33°42' S, 70° 42' W). The collected spurs showed external and internal brown necroses, starting from the tip with well-defined margins. The symptomatic tissue was cut in to small pieces (5 x 4 x 2 mm), surface disinfected by dipping in a 10% solution made from a commercial bleach solution (4,9% NaOHCl), rinsed twice in sterile water and plated on APDA (PDA Difco laboratories acidified with lactic acid (2,5 ml of 25% (vol/vol) per liter of medium). After five days at 20 °C in darkness, fast-growing, white-grey turning to black colonies were obtained, tentatively classified as a member of the Botryosphaeraceae family and two single-spore isolates (SS1, SS2) were selected for identification. Colony mycelia were first white and turned to light grey, dark grey or black, with tufts of mouse gray aerial mycelia. The pycnidia and conidia production was induced by inoculating autoclaved pine needles placed on APDA an incubation for 25 to 30 days at 20 °C in darkness. Black pycnidia solitary and globose were obtained producing hyaline, aseptate, fusiform to obovoid conidia with truncated ends with dimensions of (22.6-) 19.1 ± 1.4 (-13.3) x (6.7-) 5.5 ± 0.5 (-3.7) µm and 3.5 length/width ratio (n=100). Both isolates were identified using dichotomous keys confirming the description of Crous et al, 2006 as Neofusicoccum australe. The identification was molecularly confirmed by amplifying the nuclear ribosomal gene 5,8S (ITS1-5.8S-ITS2) using the ITS1/ITS4 primers, a partial region of β-tubulin gene (Bt2a/Bt2b), and the translation elongation factor 1-α gene (TEF1) with TEF1-728F/TEF1-986R primers. The BLASTn search revealed 100% of identity for ITS and TEF according to sequences of N. australe reference strains MT587467.1 and MK759852.1, respectively; and over 99% for β-tubulin compared to N. australe strain KX464929.1. The DNA sequences were submitted to the GenBank (ITS, OP142414, OP142416; BT, OP209981, OP209978; and TEF OP209979, OP209980) for SS1 and SS2 isolates, respectively, and deposited in the fungal collection of CChRGM - INIA, Chillán, Chile (RGM 3409 and 3410). Pathogenicity of both isolates was tested in 8-year-old asymtomatic English walnut cv. Chandler in the field during 2020 spring season, by cutting transversally 15 twigs of different tress and inoculating with a 5 day-old PDA plug. An equal number of wounded twigs were inoculated with a sterile PDA plug and served as control. After six months, all inoculated twigs developed the same necrotic lesions observed in field of 2.0 to 10.1 cm (SS1) and 1.9 to 10.8 cm (SS2) in length while control twigs showed only a scar without any dieback tissues. The inoculated pathogens of N. australe were recovered from the diseased tissues, thus fulfilling Koch's postulates. A similar dieback of walnut was reported in Chile, which caused Diplodia mutila (Díaz et al, 2018), and N. parvum (Luna et al, 2022) while N. australe has been reported in other hosts (Auger et al, 2013, Besoain et al, 2013). To the best of our knowledge, this is the first report of N. australe associated with walnut branch dieback in Chile.

Simplified and cost-effective modulatory photobioreactor setup for upscaling microalgal culture for research and semi-industrial purposes

Algal biomass and algal substances attract much interest from researchers, entrepreneurs, and farmers. Macroalgal biomass can be collected from the wild or cultivated in open tanks with a relatively low risk of contamination; however, achieving a sufficient amount of microalgal biomass is much more challenging, as the study of algal substances requires rather large amounts of biomass for extraction procedures and analyses. Due to budgetary constraints, most research institutes cannot afford to purchase large-scale ready-for-use photobioreactors, and knowledge regarding the self-construction and operation of such systems is not commonly shared. For this purpose, we present a straightforward, cost-effective methodology for modulatory mid-scale microalgal cultivation, using low-cost materials and instruments existing in most laboratories. We purchased a long polyethylene sleeve roll to assemble the photobioreactors and trimmed it to individual sleeves containing up to 20 L of culture medium each. A large medium volume was sterilized using commercial bleach (sodium hypochlorite), followed by dechlorination with thiosulfate. After a cultivation period of 7–14 days, flocculation induction was achieved by adding calcium hydroxide to facilitate an efficient harvest process. Cultures were enriched with CO2 in response to increasing pH throughout the cultivation process using a simple controller. Using an isolate of one of our species of interest, Mucidosphaerium pulchellum, we demonstrated how using one pH regulatory system can regulate a set of cultures (each in a different sleeve) to remain in the pH range 7.4–8.1 while saving CO2. This economical CO2-enrichment method increased algal growth rates by 23 %, reaching ca. 20 % higher total suspended solids compared to air-supplemented cultures. Such a cultivation system can be implemented with a surprisingly low budget of only USD800, efficiently producing hundreds of grams of biomass per cultivation period to support research on highly nutritious substances production and bioactive compounds discovery.

Large-Scale In Vitro Propagation and Ex Vitro Adaptation of the Endangered Medicinal Plant Eryngium maritimum L.

The endangered medicinal plant Eryngium maritimum L. faces significant natural and anthropogenic threats. Therefore, in vitro propagation is recommended for both conservation and commercial purposes. The aim of the study was to develop a series of protocols for seed disinfection, in vitro multiplication and rooting, and ex vitro and field adaptation. For explant disinfection, the length and temperature of three consecutive disinfectants were investigated. Macrosalt modifications of MS medium and plant growth regulator addition to media effect on axillary bud propagation rate and rooting was studied. Survival and leaf growth during ex vitro and field adaptation in response to potting media, pot cell diameter, and light spectrum were tested. Seeds treated with diluted detergent at 40 °C for 180 min, followed by 0.01% KMnO4 for 3 h and commercial bleach for 11 min, achieved a lower rate of contamination and high germination rate. Axillary bud proliferation and rooting were enhanced by reducing nitrogen content in media and adding plant growth regulators. Potting media and pot size affect survival and growth ex vitro. Timely transplantation to field conditions before overwintering increases plantlet survival. In the present work, a suitable foundation is laid to scaleup the production of E. maritimum by micropropagation.

A Simple Protocol for Mapping the Plant Root System Architecture Traits.

Comprehensive knowledge of plant root system architecture (RSA) development is critical for improving nutrient use efficiency and increasing crop cultivar tolerance to environmental challenges. An experimental protocol is presented for setting up the hydroponic system, plantlet growth, RSA spreading, and imaging. The approach used a magenta box-based hydroponic system containing polypropylene mesh supported by polycarbonate wedges. Experimental settings are exemplified by assessing the RSA of the plantlets under varying nutrient (phosphate [Pi]) supply. The system was established to examine the RSA of Arabidopsis, but it is readily adaptable to study other plants like Medicago sativa (Alfalfa). Arabidopsis thaliana (Col-0) plantlets are used in this investigation as an example to understand the plant RSA. Seeds are surface sterilized by treating ethanol and diluted commercial bleach, and kept at 4 °C for stratification. The seeds are germinated and grown on a liquid half-MS medium on a polypropylene mesh supported by polycarbonate wedges. The plantlets are grown under standard growth conditions for the desired number days, gently picked out from the mesh, and submersed in water-containing agar plates. Each root system of the plantlets is spread gently on the water-filled plate with the help of a round art brush. These Petri plates are photographed or scanned at high resolution to document the RSA traits. The root traits, such as primary root, lateral roots, and branching zone, are measured using the freely available ImageJ software. This study provides techniques for measuring plant root characteristics in controlled environmental settings. We discuss how to (1) grow the plantlets, and collect and spread root samples, (2) obtain pictures of spread RSA samples, (3) capture the images, and (4) use image analysis software to quantify root attributes. The advantage of the present method is the versatile, easy, and efficient measurement of the RSA traits.

A small-molecule fluorogenic probe for the detection of hypochlorite and its application in the bio-imaging of human breast cancer cells.

A certain amount of hypochlorite can help to regulate the body's defense system while excessive hypochlorite has some complex influence on health. Herein, a thiophene-derived biocompatible turn-on fluorescent probe (TPHZ) was synthesized and characterized for the detection of hypochlorite (ClO-). The fluorescence and colorimetric sensing of the probe followed an ICT OFF strategy. The experimental results showed a remarkable turn on fluorescence enhancement from colorless to bright blue after the addition of ClO- within 130 s in a solvent system having 80% water with high selectivity and a low detection limit of 53.8 nM. The sensing mechanism was attributed to ClO- mediated electrophilic addition to the imine bond which was justified by DFT calculations, and ESI-MS and 1H-NMR titration experiments. The probe was used in an application to visualize ClO- in human breast cancer cells which can be helpful for investigating the functions of hypochlorite in living cells. Finally, by virtue of fine photophysical properties, good sensing performance, good water solubility and low limit of detection, the probe TPHZ was successfully applied to TLC test strips, and commercial bleach and water samples.

Evaluation of Glove Performance after Decontamination.

Studies of healthcare providers doffing personal protective equipment, especially gloves, indicate that self-contamination does occur. Although generally this is not hazardous, working with particularly pathogenic organisms, such as Ebola virus and Clostridium difficile, can present a serious health risk. Decontaminating medical gloves before removal can reduce self-contamination and mitigate the spread of these types of pathogens. Also, in cases of extreme shortage, the Centers for Disease Control and Prevention (CDC) has specific recommendations for decontaminating gloves for extended use. Reuse of medical gloves is strongly discouraged by both the CDC and Food and Drug Administration. This work seeks to lay a foundation of testing to evaluate whether a decontamination method is compatible for a given glove type and material. Four potential methods of decontamination (commercial hand soap, alcohol-based hand sanitizer, commercial bleach, and quaternary ammonium solution) were tested on a variety of surgical and patient examination gloves. The method of barrier performance evaluation was ASTM D5151-19, Standard Test Method for Detection of Holes in Medical Gloves. Our results indicated that the performance of the gloves after treatment was highly dependent on the composition of the medical gloves. In general, the surgical gloves in this study performed better than the patient examination gloves, regardless of the material from which they were made. Specifically, vinyl examination gloves tended to have poorer performance. In this study, the number of gloves available to test were limited and therefore statistical significance is beyond the scope of this project.

Effectiveness of Common Disinfecting Agents against Isolates of Nannizziopsis guarroi

Nannizziopsis guarroi, a keratinophilic fungus, is an important cause of dermatomycosis in companion lizards. At this time effective disinfection protocols are unknown and additional information is needed to prevent contamination of surfaces and equipment used in the care of these animals. To this aim, the qualitative in vitro disinfecting capability of eight commonly used household and laboratory disinfectants (Novalsan®, 3% and 10% dilutions of commercial bleach, Virkon®-S, Lysol® household cleaner with hydrogen peroxide, 70% ethanol, 409® and household cleaning ammonia) were tested at two different contact times (two and ten minutes) with three different aqueous fungal concentrations of four molecularly confirmed N. guarroi isolates. A positive control after contact with saline was also grown. After contact with disinfectant or saline, the isolates were incubated, and photographic images were taken of plate growth on day 10. Images of each plate were scored using a semiquantitative scoring system. The only disinfectant that completely inhibited growth for all four isolates at both contact times and at all three isolate dilutions was 10% dilution of commercial bleach. All four isolates grew after contact with ammonia, regardless of contact time or isolate dilution and the other disinfectants showed variable inhibition of growth that was either isolate or concentration dependent or both. In conclusion, a minimum of two-minute exposure to 10% dilution of commercial bleach is recommended for disinfection of surfaces and instruments contaminated with N. guarroi.

Cyanide-Free Copper-Silver Electroplated Coatings on Carbon Steel Exposed to 5% NaClO Bleacher.

This work deals with the development of cyanide-free copper-silver electroplated coatings on AISI-1075 steel and its corrosion behavior under a 5% NaClO solution (commercial household bleach). A cyanide-free bath based on sodium thiosulfate was employed to obtain the silver coatings using current densities from 0.2 to 5.0 mA/cm2 and different concentrations of EDTA (additive). The evolution of the open circuit potential with time showed that silver is anodic with respect to copper, so there were no intense attacks in the silver pores. Adhesion measurements were made on both coatings by the tape test. The behavior against corrosion was evaluated by polarization resistance (Rp) in samples with the best coating adhesion. The best results were obtained with a silver coating of about 20 μm in thickness deposited on copper coating previously polished with colloidal silica. The best performance was attributed to the formation of AgCl as demonstrated by x-ray diffraction and scanning electron microscopy.

A New Method Based on a Zero Gap Electrolysis Cell for Producing Bleach: Concept Validation.

Commercial bleach (3.6 wt% active chlorine) is prepared by diluting highly concentrated industrial solutions of sodium hypochlorite (about 13 wt% active chlorine) obtained mainly by bubbling chlorine gas into dilute caustic soda. The chlorine and soda used are often obtained by electrolyzing a sodium chloride solution in two-compartment cells (chlorine-soda processes). On a smaller scale, small units used for swimming pool water treatment, for example, allow the production of low-concentration bleach (0.3 to 1 wt% active chlorine) by use of a direct electrolysis of sodium chloride brine. The oxidation and degradation reaction of hypochlorite ion (ClO−) at the anode is the major limiting element of this two-compartment process. In this study, we have developed a new process to obtain higher levels of active chlorine up to 3.6%, or 12° chlorometric degree. For this purpose, we tested a device consisting of a zero-gap electrolysis cell, with three compartments separated by a pair of membranes that can be porous or ion-exchange. The idea is to generate in the anode compartment hypochlorous acid (HClO) at high levels by continuously adjusting its pH to a value between 4.5 and 5.5. In the cathodic compartment, caustic soda is obtained, while the central compartment is supplied with brine. The hypochlorous acid solution is then neutralized with a concentrated solution of NaOH to obtain bleach. In this work, we studied several membrane couples that allowed us to optimize the operating conditions and to obtain bleach with contents close to 1.8 wt% of active chlorine. The results obtained according to the properties of the membranes, their durability, and the imposed electrochemical conditions were discussed.

Evaluation of the Microbiological Effectiveness of Three Accessible Mask Decontamination Methods and Their Impact on Filtration, Air Permeability and Physicochemical Properties.

The need to secure public health and mitigate the environmental impact associated with the massified use of respiratory protective devices (RPD) has been raising awareness for the safe reuse of decontaminated masks by individuals and organizations. Among the decontamination treatments proposed, in this work, three methods with the potential to be adopted by households and organizations of different sizes were analysed: contact with nebulized hydrogen peroxide (H2O2); immersion in commercial bleach (NaClO) (sodium hypochlorite, 0.1% p/v); and contact with steam in microwave steam-sanitizing bags (steam bag). Their decontamination effectiveness was assessed using reference microorganisms following international standards (issued by ISO and FDA). Furthermore, the impact on filtration efficiency, air permeability and several physicochemical and structural characteristics of the masks, were evaluated for untreated masks and after 1, 5 and 10 cycles of treatment. Three types of RPD were analysed: surgical, KN95, and cloth masks. Results demonstrated that the H2O2 protocol sterilized KN95 and surgical masks (reduction of >6 log10 CFUs) and disinfected cloth masks (reduction of >3 log10 CFUs). The NaClO protocol sterilized surgical masks, and disinfected KN95 and cloth masks. Steam bags sterilized KN95 and disinfected surgical and cloth masks. No relevant impact was observed on filtration efficiency.

Optimization of in vitro sterilization for pistachio (Pistacia vera L.) rootstocks

Pistachio (Pistacia vera L.) is one of the leading edible nut consumed all over the World due to its nutritional values. The plant is cultivated in most of the countries alongwith Turkey which is one of the the leading grower of pistachio. In Turkey, the rootstock material is currently propagated through traditional methods and there is a need of propagating plant material using modern biotechnological techniques like plant tissue culture. The provision of contaminated free explants with minimum or no phenolic compounds in the culture medium is the prerequisite of in vitro regeneration protocol. The plant material used in this study was collected at different physiological stages during different months like April- June and Sep-October. The plant material was cut into 2-3 cm long nodal segments followed by cleaning with different agents like water, soap and fungicide prior to subjected to sterilizing agents. Different sterilizing agents used in this study were HgCl2, Huwa-san (H2O2) and commercial bleach (NaOCl) for both rootstocks (UCB-1 and Buttum) with different exposure time. Sterilized explants were cultured on MS basal medium containing plant growth regulators and subcultured once a week for three weeks. Results revealed that HgCl2 as sterilizing agent was more superior than other sterilizing agents for both rootstocks. Among rootstocks, UCB-1 was more responsive than Buttum and relatively more sterilized plants were attained. On the other hand, plant material collected during June responded better and 90.0% and 50.0% sterilzied plants were attained for UCB-1 and Buttum respectively. The results revealed the significant impact of collection time, sterilizing agent type, concentration and exposure time on sterilization of P. vera rootstocks.

Stability of Free Available Chlorine Levels in Dilute Sodium Hypochlorite Solutions over a 6-Week Period.

Animal care and use programs commonly use chlorine and chlorine-based disinfectants to help prevent facility acquired infections in animals. The Department of Comparative Medicine (DCM) at Oregon Health and Science University (OHSU) follows the Centers for Disease Control and Prevention (CDC) disinfection guidelines for preparing and storing these disinfectants. DCM prepares bottles of dilute solutions of sodium hypochlorite (that is, commercial bleach) daily. In this study, we tested whether dilute bleach solutions, as prepared following the DCM protocol, remained stable under real-world practice conditions for up to 6 wk. We tested 4 groups of spray bottles filled with 0.5% bleach solutions in these experiments. Specifically, we sprayed 2 groups of bottles daily to mimic use while 2 other groups of bottles were not sprayed. We then measured free available chlorine (FAC) using 2 methods, spectrophotometry and colorimetric strips. All 4 test groups showed stable maintenance of FAC concentration for the length of the experiment. Mean FAC loss from baseline levels was not significantly different in the group of bottles not sprayed daily (6% for group 2 at week 5 compared with 7% for Group 4 at week 6). All bottles in Groups 1 and 3 measured by colorimetric strips showed concentrations at or near 5000 mg/L at all weekly time points throughout the experiment. This study shows that 0.5% sodium hypochlorite solutions stored and used in a standard rodent housing room and sprayed daily will maintain acceptable FAC concentrations for at least 5 to 6 wk, perhaps longer. In addition, we report that colorimetric strips may be a useful and accessible quality control tool for testing freshly prepared solutions at regular intervals. We conclude that sodium hypochlorite solutions can be prepared on a weekly, biweekly, or monthly basis with no loss in disinfection effectiveness.

In Vitro Propagation of Manihot Esculenta Crantz ‘Pirun 2’

Abstract In Thailand, cassava (Manihot esculenta Crantz ‘Pirun 2’) is an important economic crop. The tissue culture technique is used to produce true-to-type cassava plantlets on a large scale within a short period. Therefore, the objective of this study was to investigate the optimum culture medium for cassava axillary bud in vitro propagation. Stem nodes were treated with a solution of 20% (v/v) commercial bleach (25% w/v NaOCl) for 10 minutes. Then, the sterilized buds were cultured on three different types of culture media: Murashige and Skoog (MS), Driver and Kuniyaki Walnut (DKW), and MS supplemented with NAA and BA. Various parameters were evaluated for their effects on plantlet development (height of shoot and numbers of leaves, roots, and shoots after 1 month). The results showed that the mean (± standard deviation) numbers of leaves (6.67 ± 0.82) and roots (2.50 ± 0.55) were significantly higher when they were cultured on MS medium. In addition, the highest number of shoots (3.67±0.82) was obtained on MS medium supplemented with 0.05 mg/l NAA+1 mg/l BA. The cut shoots of plantlets cultured on MS medium without hormones developed into mature plantlets after 1 month. Thus, the MS medium was the optimum for mature cassava Pirun 2 culture. This protocol would be useful for plantlet induction on MS medium supplemented with NAA and BA hormones to produce more shoots and for transfer to MS medium without rooting hormones. Moreover, in vitro derived plantlets were successfully acclimatized on a peat moss which gave the high percentage of transplanting survival (100%). Keywords: Axillary bud, Cassava, Stem node, Surface sterilization, Tissue culture