Utilization of bioethanol generated from papaw peel waste for hand sanitizer production

Hands are the primary mode for the spread of microbes. For infection control, the first-line of defense as well as personal hygiene, are mandatory. Hand sanitizers that contain ethanol as the main constituent are used to kill a broad range of microbes. Demand for petroleum-derived ethanol is increasing with the COVID-19 outbreak and primary suppliers are searching for alternatives to overcome this problem. Objective of this study is to produce bioethanol from ripen papaw peel waste using Saccharomyces cerevisiae and to determine the potential utilization of bioethanol generated from papaw peel waste for a pilot study of which the end aim is hand sanitizer production. The blended ripened papaw (Carica papaya) fruit peel (100g/L) was inoculated with the S. cerevisiae (2g/L) in a fermentation medium that contains 10 g/L yeast extract, 10 g/L KH2PO4, 2 g/L (NH4)2SO4 and 0.5 g/L MgSO4•7H2O and allowed to ferment for 6-36 hours at room temperature. The bioethanol yield obtained after 12 hours, was 0.6% (V/V). The fermentation conditions were optimized by changing one factor at a time, while keeping the other variables constant. Significantly higher bioethanol yield (6.2 times, 3.7% V/V [p<0.05]) was obtained from papaya peels at the optimized conditions of 12 hours of incubation period, 5:1 ratio between air space and fermentation solution, 5g/L of yeast inoculum, 15g/100ml of papaw fruit peel, 1g/100ml of soybean powder as nitrogen source, 60ml/100ml of diluted sulfuric acid at pH 5. When the agar well diffusion assay was performed against pathogenic bacteria such as Escherichia coli, Staphylococcus aureus, Bacillus spp. and Pseudomonas spp, all the bacterial strains showed an inhibition zone, i.e., they were sensitive for the bioethanol extract.            KEYWORDS:  Saccharomyces cerevisiae, Bioethanol, Papaw peel waste, Soybea

Optimization of Fermentation for Bioethanol Production from sour Citrus aurantifolia Fruit Juice using Natural Palmyrah Toddy Yeast

Large scale consumption of fossil fuel to meet the increasing demand causes adverse effects on the environment due to the emission of harmful greenhouse gases. The production of bioethanol from diverse fruit juices that are underutilized because of poor taste quality could be one of the alternative fuels to overcome the issues. The objective of the study was to produce bioethanol from sour Citrus aurantifolia fruit juice using palmyrah toddy yeast and to optimize the conditions to increase the bioethanol yield. The sour Citrus fruit juice was inoculated with palmyrah toddy yeast (Saccharomyces cerevisiae - 2g/L) in the fermentation media (100ml, sour Citrus fruit juice: distilled water = 1:3) composed of 10 g/L yeast extract, 10 g/L KH2PO4, 2 g/L (NH4)2SO4, 2 g/L peptone and 0.5 g/L MgSO4·7H2O and allowed for fermentation for 24 hours at room temperature. The amount of ethanol produced from the Citrus juice was 0.8% (V/V) after 24 hours of fermentation. In order to optimize the fermentation process for Citrus aurantifolia, a variety of experimental parameters were studied, including the type of nitrogen source (ammonium sulphate, ammonium nitrate, ammonium chloride, and urea), inoculum size (0.4 to 1.0 g/100 mL), temperature (20 to 40 °C), rotation speed (50 to 250 rpm), concentration of raw fruit juice (5 to 100%), amount of urea (0.1 to 2.0 g/100 mL), carbon source (glucose, sucrose, maltose, and dextrose), amount of sucrose (1 to 20 g), pH of the medium (3.0 to 8.0), and incubation period (24 to 96 h). After conducting the experiments, it was found that using Citrus aurantifolia at 100% concentration resulted in significantly higher ethanol yields of 11.50%, which was 14.37 times higher than the non-optimized conditions. The highest yield was achieved when the fermentation was carried out at 35 °C for 24 h with an inoculum concentration of 0.5 g/100 mL, a rotation speed of 150 rpm, a pH of 4.0, 0.1 g/100 mL urea as the nitrogen source, and 10 g/100 mL sucrose as the carbon source. Large scale fermentation study using bioreactor should be done to determine whether this finding could be commercialized. Key words: Bioethanol, Fermentation, Palmyrah toddy yeast, Citrus fruit juice, Ure

Bioconversion of Single Cell Protein from Underutilised Seaweed Turbinaria sp. using Natural Palmyrah Toddy Yeast

This study was aimed to produce Single Cell Protein (SCP) from underutilied, abundantly found marine seaweed Turbinaria sp. using natural yeast from palmyrah (Borassus flabellifer) toddy. Turbinaria sp. were collected, sun-dried, ground to powder form and Turbinaria solution was made by mixing distilled water and this was used as a growth medium throughout the experiment without adding any supplements. The experiments were performed in a shaking incubator with the fermentation medium of Turbinaria sp. 100 g/L (10%) inoculated with 10 mL natural palmyrah toddy. Fermentation was carried out at 29o C for 72 h and the crude protein content was determined using Kjeldahl apparatus (38.46%). When the growth temperature was optimised at 35o C, crude protein yield obtaine was significantly increased by 1.36 times than the initial non-optimised condition with temperature 27oC. When fermentation time was optimised as 48 h (44.33%), crude protein yield was significantly increased by 1.14 times than the initial fermentation time (24 h-38.55%). When different combinations of Turbinaria sp. media and inoculum ratio (55:05, 50:10, 40:20, 30:30 and 20:40) were used as medium, crude protein yield was significantly increased by 1.44 times (50:10-43.72%) than the initial media inoculum ratio (55:05-30.21%). When initial pH of the media was changed (5.0, 6.0, 7.0, 8.0 and 9.0), significantly higher relative crude protein yield was obtained with the initial pH value 6.0 (Turbinaria medium-90.97%). Amino acid analysis revealed that the SCP produced from the Turbinaria medium had all the essential amino acids with comparatively higher amount of methionine (3.9%) and lower amount of threonine (0.2%). Vitamin B analysis revealed that SCP yield from Turbinaria medium contained thiamin (0.85 mg/100 g) and riboflavin (3.2 mg/100 g). After the optimisation of culture growing conditions and media composition, SCP production from the excessively grown, underutilised seaweed Turbinaria, was significantly increased by 1.13 times (from 38.46 to 43.72%) with palmyrah toddy mix.Key words: crude protein, palmyrah toddy mix, single cell protein (SCP), Turbinaria sp

Kinematic Synthesis and Analysis of Four Bar Mechanism Using Expert System

A considerable amount of research has been carried out on the synthesis of mechanisms with linkages. Such mechanisms can be used in many ways and in general, synthesis is carried out with reference to input positions and output positions. In this study, the expert system analyzes the four bar double rocker mechanism for given set of inputs which includes the distance of the ground pivots depending upon the space constraint for the mounting of the mechanism, the angles of swing of the input link and the angle of swing required by the output link. The results of the kinematic synthesis and analysis module of the expert system have been compared using a standard problem

Influence of pyrogallol antioxidant on performance and emissions of a CI fuelled with neem oil biodiesel

In current circumstances, energy is considered as a critical factor for economic growth, social development and human welfare. To bridge the ever rising energy requirement, biodiesel an alternative diesel fuel derived from waste vegetable oil, animal fats or vegetable oil is becoming increasingly popular in developing countries. Amongst which the biodiesel derived from neem oil has already proved as potential alternative fuel for CI engine. However the studies which investigate performance and emission characteristics with additives need to be investigated. In the present investigation the neem oil biodiesel was prepared using acid catalyzed esterification followed by trans-esterification process. The performance and emission characteristics of a single cylinder Compression ignition engine was carried with pyrogallol concentration of 0 parts per million (ppm), 250ppm, 500ppm and 750ppm with neem oil biodiesel. The engine performance and emission tests were carried out at a rated speed of 1500 rpm under different loading conditions. An improved performance and emission characteristics of engine was found with addition of pyrogallol as additives in neem oil biodiesel

Production of Single Cell Protein Using Mixed Culture of Toddy with Banana Fruit Juice: A Cost Effective Method

Since the increase in low quality protein food has been an issue in the developing countries, there is a need to explore good alternative protein sources. This study attempted to compare the single cell protein (SCP) production with baker’s yeast and mixed culture of toddy from banana fruit juice in the Liquid State Fermentation (LSF) system. Fermentation media composed of glucose 10 g/l. MgSO4 0.5, NaCl 0.1, CaCl2 0.1 and KH2PO4 1 g/l as control medium inoculated with toddy and 100 ml/l (10%) of banana fruit juice was replaced instead of glucose for banana medium. When the culture growing conditions (inoculum size- baker’s yeast: 0.5g and natural toddy: 5ml) of the fermentation processes were optimised separately, higher SCP production was achieved when time and temperature maintained as 3 days and 30o C respectively with 40.29% baker’s yeast and 40.95% palmyrah toddy mix for banana medium. When the carbon source was replaced with 5% fruit juice, the SCP production significantly increased to 40.87% and 41.18% with baker’s yeast and toddy mix respectively. This comparative fermentation study with baker’s yeast and palmyrah toddy mix revealed that palmyrah toddy mix produces significantly higher protein content than that of baker’s yeast. Findings suggest that cheap and naturally available palmyrah toddy mix yield higher SCP than the expensive and processed baker’s yeast in the banana extract added fermentation medium.Keywords: Baker’s yeast, Banana fruit extract, Palmyrah toddy mix, Single cell protei

Bioethanol production from <em>Chara globularis</em> using yeast and yield improvement by optimization of conditions

The rising population, depletion of petroleum-based fossil fuel and atmospheric contaminations by combustion of fossil fuel have opened avenues for alternative, eco-friendly and renewable energy sources. Bioethanol is an alternative and renewable source that has drawn attention due environmental concerns and energy security with non-renewable sources. This study was aimed at determining the potential bioethanol producing freshwater flora that are abundantly available in the Northern Province of Sri Lanka using Saccharomyces cerevisiae and to optimize the fermentation conditions to enhance the ethanol yield from Chara globularis. Freshwater flora such as C. globularis, Cabomba caroliniana, Spirodela polyrhiza, Salvinia minima, Salvinia natans, Wolffia arrhiza and Wolffia globosa were hydrolysed with 1M sulfuric acid solution to determine the reducing sugar and bioethanol yields. C. globularis produced a higher amount of reducing sugar and bioethanol than other species tested. When C. globularis was pre-treated with 1 M acid solutions (sulfuric acid, nitric acid, and hydrochloric acid) and alkaline solutions (sodium hydroxide and potassium hydroxide), a higher reducing sugar and bioethanol yields were obtained with sulfuric acid. When bioethanol was produced from C. globularis using S. cerevisiae following three different hydrolysis methods viz., acid hydrolysis (1 M sulfuric acid), enzymatic hydrolysis (1% alphaamylase) and combination of chemical and enzymatic hydrolysis (1 M sulfuric acid and 1% alpha-amylase), the combination of chemical and enzymatic hydrolysis gave a higher yield, thus was selected. The conditions for fermentation of C. globularis substrate using S. cerevisiae were optimized sequentially by changing one factor at a time while keeping the other variables constant. After the optimization of fermentation time (24 hours), operating temperature (35 °C), rotation speed (200 rpm) and sulfuric acid concentration for combined pre-treatment (0.75 M) with an inoculum size of 100 g l-1, bioethanol yield was increased

Comprehensive analysis of physicochemical, nutritional, and antioxidant properties of various forms and varieties of tender coconut (Cocos nucifera L.) water in Northern Sri Lanka

Tender coconut water is a beverage distinguished from mature coconut water as it's harvested during the early stages of coconut development. It's a well-liked natural drink in tropical regions where coconut trees are abundant. This study aimed to characterize the physicochemical, nutritional and antioxidant properties of different varieties of tender coconut water such as tall, dwarf, intermediate and hybrid varieties with a maturity stage of 5–7 months old. Standard assays assessed nutritional and antioxidant properties. The results of this study showed that the King coconut (Intermediate variety), had significantly higher total protein (0.59 mg BSA/ ml), Total soluble solids (5.0° Brix) and Total sugar content (63.58 mg/ml). The coconut water of Ran thembili (Tall variety) showed significantly higher antiradical activity (DPPH) (82.75 %), total tannin content (22.32 µg TE/ml) and reducing sugar content (43.80 mg/ml). Nawasi (Tall variety) showed significantly higher total flavonoid content (1.23 µg QE/ ml). Total phenolic content and total antioxidant activity were significantly higher for Ran thembili and King coconut. In essence, our findings illuminated the diverse and appealing attributes of tender coconut water. Importantly, the distinct coconut varieties examined in this study exerted a noticeable impact on the composition and properties of tender coconut water