'Mato Peiyu' pomelo (Citrus grandis (L.) Osbeck 'Mato Peiyu') leaves from pruning are currently an agricultural waste. The aim of this study was to isolate essential oils from these leaves through steam distillation (SD) and solvent-free microwave extraction (SFME) and to evaluate their applicability to skin care by analyzing their antimicrobial, antioxidant (diphenyl-1-picrylhydrazyl scavenging assay, β-carotene/linoleic acid assay, and nitric oxide scavenging assay), anti-inflammatory (5-lipoxygenase inhibition assay), and antityrosinase activities. The gas chromatography-mass spectrometry results indicated that the main components of 'Mato Peiyu' leaf essential oils were citronellal and citronellol, with a total percentage of 50.71% and 59.82% for SD and SFME, respectively. The highest bioactivity among all assays was obtained for 5-lipoxygenase inhibition, with an IC50 value of 0.034% (v/v). The MIC90 of the antimicrobial activity of essential oils against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans ranged from 0.086% to 0.121% (v/v). Citronellal and citronellol were the main contributors, accounting for at least 54.58% of the essential oil's bioactivity. This paper is the first to report the compositions and bioactivities of 'Mato Peiyu' leaf essential oil, and the results imply that the pomelo leaf essential oil may be applied in skin care.
Ginger essential oils (GEO) are natural products with antibacteria properties consisting of many different volatile
compounds have high potential to be used in many applications. In this study, the ginger GEO was successfully
encapsulated in chitosan as a carrier agent using a spray drying technique. The extraction of Zingiber officinale
(ginger) essential oil is performed by steam distillation method. The GEO was encapsulated in chitosan as a carrier
agents at 1:3, GEO:chitosan ratio by using spray drying technique. GEO together with encapsulated GEO were
further assayed for antimicrobial activity by disc-diffusion method. For characterization of encapsulated GEO,
Fourier transform infrared spectroscopy (FTIR) and Field emission scanning electron microscopy (FESEM) were
used. FTIR analysis revealed that there was no existence of a new functional group in the encapsulated GEO
showing that there is only physical interaction between GEO and chitosan. Besides, FESEM analysis showed the
encapsulated GEO were in micro in sizes and possessed spherical shape with smooth and porous surface.
Furthermore, Both GEO and encapsulated GEO showed in vitro antimicrobial activity against Escheriachia coli,
Pseudomonas aeruginosa, Staphylococcus aureus and Salmonella typhi with encapsulated GEO possessed higher in
the activities for all studied bacteria compared to GEO. The encapsulated GEO demonstrated a superior performance
against Salmonella typhi with the inhibition zone of 22.5 mm compared to GEO only 13.5 mm. The results obtained
indicated that due to the volatility and instability of the GEO when exposed to environmental factors, its encapsulation considerably improve and enhanced its performance.
Ylang-ylang (Cananga odorata Hook. F. & Thomson) is one of the plants that are exploited at a large scale for its essential oil which is an important raw material for the fragrance industry. The essential oils extracted via steam distillation from the plant have been used mainly in cosmetic industry but also in food industry. Traditionally, C. odorata is used to treat malaria, stomach ailments, asthma, gout, and rheumatism. The essential oils or ylang-ylang oil is used in aromatherapy and is believed to be effective in treating depression, high blood pressure, and anxiety. Many phytochemical studies have identified the constituents present in the essential oils of C. odorata. A wide range of chemical compounds including monoterpene, sesquiterpenes, and phenylpropanoids have been isolated from this plant. Recent studies have shown a wide variety of bioactivities exhibited by the essential oils and the extracts of C. odorata including antimicrobial, antibiofilm, anti-inflammatory, antivector, insect-repellent, antidiabetic, antifertility and antimelanogenesis activities. Thus, the present review summarizes the information concerning the traditional uses, phytochemistry, and biological activities of C. odorata. This review is aimed at demonstrating that C. odorata not only is an important raw material for perfume industry but also considered as a prospective useful plant to agriculture and medicine.
The formation of aqueous two-phase system (ATPS) with the environmentally friendly and recyclable ionic liquid has been gaining popularity in the field of protein separation. In this study, the ATPSs comprising N,N-dimethylammonium N',N'-dimethylcarbamate (DIMCARB) and thermo-responsive poly(propylene) glycol (PPG) were applied for the recovery of recombinant green fluorescent protein (GFP) derived from Escherichia coli. The partition behavior of GFP in the PPG + DIMCARB + water system was investigated systematically by varying the molecular weight of PPG and the total composition of ATPS. Overall, GFP was found to be preferentially partitioned to the hydrophilic DIMCARB-rich phase. An ATPS composed of 42% (w/w) PPG 1000 and 4.4% (w/w) DIMCARB gave the optimum performance in terms of GFP selectivity (1,237) and yield (98.8%). The optimal system was also successfully scaled up by 50 times without compromising the purification performance. The bottom phase containing GFP was subjected to rotary evaporation of DIMCARB. The stability of GFP was not affected by the distillation of DIMCARB, and the DIMCARB was successfully recycled in three successive rounds of GFP purification. The potential of PPG + DIMCARB + water system as a sustainable protein purification tool is promising.
High production costs of biosurfactants are mainly caused by the usage of the expensive substrate and long fermentation period which undermines their potential in bioremediation processes, food, and cosmetic industries even though they, owing to the biodegradability, lower toxicity, and raise specificity traits. One way to circumvent this is to improvise the formulation of biosurfactant-production medium by using cheaper substrate. A culture medium utilizing palm fatty acid distillate (PFAD), a palm oil refinery by-product, was first developed through one-factor-at-a-time (OFAT) technique and further refined by means of the statistical design method of factorial and response surface modeling to enhance the biosurfactant production from Pseudomonas sp. LM19. The results shows that, the optimized culture medium containing: 1.148% (v/v) PFAD; 4.054 g/L KH2PO4; 1.30 g/L yeast extract; 0.023 g/L sodium-EDTA; 1.057 g/L MgSO4·7H2O; 0.75 g/L K2HPO4; 0.20 g/L CaCl2·2H2O; 0.080 g/L FeCl3·6H2O gave the maximum biosurfactant productivity. This study demonstrated that the cell concentration and biosurfactant productivity could reach up to 8.5 × 109 CFU/mL and 0.346 g/L/day, respectively after seven days of growth, which were comparable to the values predicted by an RSM regression model, i.e., 8.4 × 109 CFU/mL and 0.347 g/L/day, respectively. Eleven rhamnolipid congeners were detected, in which dirhamnolipid accounted for 58% and monorhamnolipid was 42%. All in all, manipulation of palm oil by-products proved to be a feasible substrate for increasing the biosurfactant production about 3.55-fold as shown in this study.
The fractions of fatty acid methyl esters (FAME) i.e. crude palm oil methyl esters (CPOME), RBD palm olein methyl esters (RBD Palm Olein ME) and used frying oil methyl esters (UFOME) rich in unsaturated fatty esters were used to prepare alkenyl succinic anhydrides (ASA). The fractions were obtained via fractional distillation that separated the unsaturated fatty esters from the saturated fatty esters. The fractions with the highest content of unsaturated fatty esters were reacted with maleic anhydride (MA) for 8 hours at 240oC with the MA/FAME ratio of 1.5. The reaction was conducted without catalyst and solvent. The crude alkenyl succinic anhydride (ASA) obtained was purified by column chromatography. The purified compound was characterised by FTIR.
This study was conducted to evaluate the phytochemical contents and antimalarial properties of the oils extracted from the leaves of Malaysian Plectranthus amboinicus in mice infected with Plasmodium berghei. The essential oils were extracted and prepared by using steam distillation technique and subjected to phytochemical screening by using GC-MS. Antimalarial activity of different extract doses of the essential oil was tested in vivo in ICR mice infected with Plasmodium berghei (PZZ1/100) during early, established and residual infections. In all, 5 compounds made up 88.34% of total oil and the major chemical compounds were carvacrol (85.14%), thymoquinone (1.65%), terpinen-4-ol (0.70%), octenol (0.62%) and thymol (0.23%). Antimalarial assay showed this essential oil as a potential prophylactic agent with the percentage chemosuppression of 45.23%, 18.28%, 45.38% and 58.26% while treated with 50, 200, 400 and 1000 µL/kg respectively of essential oil and curative agent with percentage of chemo suppression of 54.10%, 47.35%, 56.75% and 65.38% while treated with the above dose of essential oil. Statistically no reduction of parasitemia was calculated for suppressive test. The extract has prophylactic and curative effects on P.berghei in mice
Membrane distillation (MD) is a thermally driven technology applied in desalination and water reuse with utilisation of sustainable energy. However, algal organic matter (AOM) could foul membrane critically and plague MD's long-term operational stability. In this study, the soluble extracellular polymeric substance (sEPS) and intracellular organic matter with bound extracellular polymeric substance (IOM + bEPS) of two algal species (Amphora coffeaeformis and Navicula incerta) were exposed to 60 °C, 70 °C and 80 °C for 8 h with polypropylene hydrophobic membrane, simulating heated AOMs contacted with membrane inside MD unit, to study the temperature effect on membrane fouling. The dissolved carbohydrate and protein in the sEPS and IOM + bEPS samples generally increased after being heated. Heating caused cell lysis and the release and dissolution of carbohydrate and protein from sEPS, IOM and bEPS into water. As heating temperature increased, the carbohydrate release from the AOM usually increased. The contact angle of membrane contacted with sEPS and IOM + bEPS reduced significantly after heat treatment. The reduction in IOM + bEPS was larger than sEPS, in line with SEM analysis, indicating membrane surfaces and pores with IOM + bEPS fouled more severely than sEPS. It is due to higher hydrophobicity in IOM + bEPS causing adherence to membrane and presence of amphiphiles. High protein, lipid, and saturated fats proportions also cause severe fouling. SEM-EDX analysis indicated presence of O, Na, Cl and Mg elements, pointing to carbohydrate and lipids, and salt trapped in foulants. AOM heating and composition had direct effect to the membrane integrity, dictating severity of fouling in MD operations.
Membrane distillation (MD) is an attractive technology for the separation of highly saline water used with a polytetrafluoroethylene (PTFE) hollow fiber (HF) membrane. A hydrophobic coating of low-density polyethylene (LDPE) coats the outer surface of the PTFE membrane to resolve membrane wetting as well as increase membrane permeability flux and salt rejection, a critical problem regarding the MD process. LDPE concentrations in coating solution have been studied and optimized. Consequently, the LDPE layer altered membrane morphology by forming a fine nanostructure on the membrane surface that created a hydrophobic layer, a high roughness of membrane, and a uniform LDPE network. The membrane coated with different concentrations of LDPE exhibited high water contact angles of 135.14 ± 0.24 and 138.08 ± 0.01° for membranes M-3 and M-4, respectively, compared to the pristine membrane. In addition, the liquid entry pressure values of LDPE-incorporated PTFE HF membranes (M-1 to M-5) were higher than that of the uncoated membrane (M-0) with a small decrease in the percentage of porosity. The M-3 and M-4 membranes demonstrated higher flux values of 4.12 and 3.3 L m-2 h-1 at 70 °C, respectively. On the other hand, the water permeation flux of 1.95 L m-2 h-1 for M-5 further decreased when LDPE concentration is increased.
Introduction: This is a proto-type product which is based on Frankincense essential oil and hydrosol. Methods: Three oleo gum resin species, namely; Boswellia carterii (BC), Boswellia frereana (BF), and Commiphora myrrha (CM) of Burceraceae family were extracted for their essential oil by hydro-distillation. They were screened for their poten-tial of anti-cariogenic activity by in-vitro experimental study of two main bacterial species (Streptococcus mutans and Lactobacillus spp), which are considered the main cause of dental and mouth diseases. Results: Methanol and acetone extracts of the three plants inhibited the growth of the bacteria. However, BF-methanol extract shows the greatest inhibition followed by BC and CM respectively. Hence, the obtained result encourages proceeding further thorough investigation to benefit the positive outcomes of these plant extracts in terms of introducing new potential antimicrobial formulations, such as mouth wash which can be used for mouth cleansing and protection from the diseases such as mouth ulcers, gingivitis, sinusitis, glandular fever and brucellosis as well as dental caries. This result can be converted to Boswellia Mouthwash Essential Oil (BosMEO) and Boswellia Mouthwash Hydrosol (BosMoHy) based products. This new plant extract product can be exploited for further research for its potential used as moth infection natural treatments such as mouth ulcers, gingivitis, sinusitis, glandular fever, brucellosis as well as respi-ratory problem. It is free of synthetic chemicals, organic, natural, plant based, and halal with no major health side effects. Conclusion: Plant-based product which is free from synthetic chemicals and with minimal side effects will satisfy its quality efficiency.
Pineapple peel is a potential feedstock for the extraction of essential oil due to the presence of aromatic compounds. To extract the essential oil from pineapple peels, three different methods were applied, i.e., (1) hydro-distillation (HD); (2) hydro-distillation with enzyme-assisted (HDEA); and (3) supercritical fluid extraction (SFE). SFE had successfully produced an essential oil with the yield of 0.17% (w/w) together with 0.64% (w/w) of concrete, whereby the HD and HDEA had only produced hydrosols with the yield of 70.65% (w/w) and 80.65% (w/w), respectively. Parameters' optimization for HD (substrate to solvent ratio, temperature, and extraction duration) and HDEA (cellulase loading and incubation duration) significantly affected the hydrosol yield, but did not extract out the essential oil. This is because only SFE had successfully ruptured the oil gland after observed under the scanning electron microscope. The essential oil obtained from SFE composed of mainly propanoic acid ethyl ester (40.25%), lactic acid ethyl ester (19.35%), 2-heptanol (15.02%), propanol (8.18%), 3-hexanone (2.60%), and butanoic acid ethyl ester (1.58%). In overall, it can be concluded that the SFE had successfully extracted the essential oil as compared to the HD and HDEA methods.
The total mass attenuation coefficients (μ/ρ) of stainless steel (SS316L) and carbon steel (A516) that are widely used as petrochemical plant components, such as distillation column, heat exchanger, boiler and storage tank were measured at 662, 1073 and 1332 keV of photon energies. Measurements of radiation intensity for various thicknesses of steel were made by using transmission method. The γ-ray intensity were counted by using a Gamma spectrometer that contains a Hyper-pure Germanium (HPGe) detector connected with Multi Channel Analyzer (MCA). The effective numbers of atomic (Zeff) and electron (Neff) obtained experimentally were compared by those obtained through theoretical calculation. Both experimental and calculated values of Zeff and Neff were in good agreement.
Kaffir lime or “limau purut” (Citrus hystrix) is a popular traditional herbal plant with aromatic leaves. It produces fruits which are commonly used in Asian cuisines as a flavouring agent. Essential oil has been a popular and valuable product applicable in various industries, but its availability is scarce. Essential oil from the leaves of Citrus hystrix is a complex mixture of volatile and semi-volatile compounds. It is rich in bioactive molecules that act synergistically to improve the well-being of an individual. Essential oil is extracted from Citrus hystrix leaves using a few extraction methods; however, the most excellent extraction methods have yet to be ascertained. This review paper highlights several extraction methods that determined the final yield of Citrus hystrix leaves’ essential oil and the comparison of advantages and disadvantages between each method. Two types of methods are discussed, which are conventional and modern methods. Conventional methods include hydro-distillation, steam distillation, Soxhlet distillation and solvent extraction, while the modern method includes pressurized liquid extraction (PLE). In addition, pre- treatment processes are also included as they can significantly affect the performance of other important processes and production yield. This paper also found that the highest yield of 56.16% was obtained using PLE method. Essentially, each of the extraction and pre-treatment methods has its own pros and cons; hence choosing a suitable method depends heavily on the producer's demand and requirement.
Lemongrass leaves are often under-utilised and unexploited. In this study, lemongrass leaves were used to produce water soluble essential oil using a steam distillation system. Water steam was passed through the lemongrass leaves which were placed and supported on a grid above the water in a distiller. The steam distillation system was fabricated and optimised using Response Surface Methodology (RSM). The maximum oil yield with optimal relative citral content is obtained at 6.69 of plant-to-water ratio, 26.68 minutes of distillation time using air-dried lemongrass leaves left under the shade for two days. At the optimum conditions, the predicted oil yield was 0.6719% of lemongrass (C. citratus) oil which contains 71.79% of citral content.
Rhodinol is a mixture of geraniol and citronellol. It is the second fraction in fractional distillation of commercially grown Cymbopogon nardus. The physical and chemical similarities of these two compounds made them inseparable. The individual use of each compound is of great importance. A selective oxidation (hydrogen peroxide activated by platinum black) of geraniol (in rhodinol) to geranial was done while remaining citronellol intact in order to separate the two compounds into different chemical functionality. A yield of 81% geranial achieved while minimizing citronellal formation from citronellol to 17%. Chemical separation using sodium hydrogen sulfite (NaHSO3) was done to separate the aldehydes from the unreacted citronellol. Purification using fractional distillation was done to obtain pure geraniol and remove minor fraction of citronellal.
Researchers in recent years have utilized a broad spectrum of treatment technologies in treating bakers' yeast production wastewater. This paper aims to review the treatment technologies for the wastewater, compare the process technologies, discuss recent innovations, and propose future perspectives in the research area. The review observed that nanofiltration was the most effective membrane process for the treatment of the effluent (at >95% pollutant rejection). Other separation processes like adsorption and distillation had technical challenges of desorption, a poor fit for high pollutant load and cost limitations. Chemical treatment processes have varying levels of success but they are expensive and produce toxic sludge. Sludge production would be a hurdle when product recovery and reuse are targeted. It is difficult to make an outright choice of the best process for treating the effluent because each has its merits and demerits and an appropriate choice can be made when all factors are duly considered. The process intensification of the industrial-scale production of the bakers' yeast process will be a very direct approach, where the process optimisation, zero effluent discharge, and enhanced recovery of value-added product from the waste streams are important approaches that need to be taken into account.
In this work, poly(MBAAm-co-SBMA) zwitterionic polymer nanoparticles were synthesized in one-step via distillation-precipitation polymerization (DPP) and were characterized. [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA) as monomer and N, N'-methylene bis(acrylamide) (MBAAm) as cross-linker are used for the synthesis of nanoparticles. As far as our knowledge, this is the first such report on the synthesis of poly(MBAAm-co-SBMA) nanoparticles via DPP. The newly synthesized nanoparticles were further employed for the surface modification of polysulfone (PSF) hollow fiber membranes for dye removal. The modified hollow fiber membrane exhibited the improved permeability (56 L/ m2 h bar) and dye removal (>98% of Reactive Black 5 and >80.7% of Reactive orange 16) with the high permeation of salts. Therefore, the as-prepared membrane can have potential application in textile and industrial wastewater treatment.
Functional surfaces and polymers with branched structures have a major impact on physicochemical properties and performance of membrane materials. With the aim of greener approach for enhancement of permeation, fouling resistance and detrimental heavy metal ion rejection capacity of polyetherimide membrane, novel grafting of poly (4-styrenesulfonate) brushes on low cost, natural bentonite was carried out via distillation-precipitation polymerisation method and employed as a performance modifier. It has been demonstrated that, modified bentonite clay exhibited significant improvement in the hydrophilicity, porosity, and water uptake capacity with 3 wt. % of additive dosage. SEM and AFM analysis showed the increase in macrovoides and surface roughness with increased additive concentration. Moreover, the inclusion of modified bentonite displayed an increase in permeation rate and high anti-irreversible fouling properties with reversible fouling ratio of 75.6%. The humic acid rejection study revealed that, PEM-3 membrane having rejection efficiency up to 87.6% and foulants can be easily removed by simple hydraulic cleaning. Further, nanocomposite membranes can be significantly employed for the removal of hazardous heavy metal ions with a rejection rate of 80% and its tentative mechanism was discussed. Conspicuously, bentonite clay-bearing poly (4-styrenesulfonate) brushes are having a synergistic effect on physicochemical properties of nanocomposite membrane to enhance the performance in real field applications.
Fat, oil and grease in wastewater generated from household kitchens, restaurants and food processing plants affect sewer systems, water resources and environment adversely. Hence, membrane distillation of saline and oily water was studied using a nearly superhydrophobic membrane developed in this work. Polyvinylidene fluoride (PVDF) membrane incorporated SiO2 nanoparticles was synthesized via phase inversion with dual baths and modified using hexadecyltrimethoxy silane. The volume ratio of silane to ethanol was varied between 1:200 to 1:25. The membrane characteristics were examined using a goniometer, a porometer, scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The PVDF-SiO2 membrane modified using the volume ratio of 1:50 achieved the highest water contact angle of 141.6° and LEP of 2.642 bar. This membrane was further tested in membrane distillation to observe the permeate flux of distilled water, saline solution (1 M NaCl) as well as saline and oily solution (1 M NaCl; 1,000 ppm of palm oil). The modified PVDF/SiO2 showed high permeate flux which is nearly four times of the permeate flux of neat PVDF membrane, but still susceptible of salt and oil fouling as shown in SEM images.
Membrane distillation (MD) is an advantageous separation process compared with pressure-driven technologies and was subsequently introduced to treat aquaculture wastewater. Harnessing a superhydrophobic membrane in an MD process is of extreme importance to prevent membrane wetting. In this work, the electrospun polypropylene (PP) membrane was surface modified by depositing an additional coating of PP via the solvent-exchange method, thereby improving the membrane's superhydrophobicity. Layer-by-layer deposition of PP caused the formation of uniform polymer spherulites on the membrane surface, which levelled up the membrane's surface roughness. A superhydrophobic surface was achieved by applying a single-layered PP coating, with static water contact angle of 152.2° and sliding angle of 12.5°. While all membranes achieved almost perfect salt rejection (up to 99.99%), the MD permeate flux improved by 30%, average of 13.0 kg/m2h, when the single-layered PP-coated membrane was used to treat the high salinity water in both 2 and 60 hr MD processes. Further layers of coating resulted in larger size of PP spherulites with higher sliding angle, followed by lowered flux in MD. The evenness of the surface coating and the size of the aggregate PP spherulites (nano-scaled) are two predominant factors contributing to the superhydrophobicity character of a membrane.