ANALISIS SIFAT MEKANIS KOMPOSIT POLYESTER YANG DIPERKUAT SERAT KULIT DURIAN (DURIO ZIBETHINUS MURR) AKIBAT VARIASI FRAKSI VOLUME

Durian rind fiber composite as a reinforcement is one of the interesting research areas. Some of the advantages associated with using natural fibers due to reinforcement in polymers are their non-abrasive properties and low-cost consumption. Durian rind when processed further can be made into cellulose fiber which can be used as a natural filler in unsaturated polyester composites. Among various types of natural fibers, durian skin fiber is an alternative polymer composite filler. Durian skin can be obtained easily because it is a family waste that has not been used. To get a new composite material made from durian skin waste, and to help the community and government in handling durian skin waste. The purpose of this study was to determine the maximum value of the variation of the volume fraction of durian skin fiber on the impact strength and hardness strength according to the desired application. This study uses the Hand Lay Up method, in the manufacture of single fiber composites with variations in volume fraction of durian skin fiber: polyester matrix, namely, 10%: 90%, 20%: 80%, 30%: 70%, 40%: 60% and 50 %:50%. The results showed that there was an increase in the impact strength and hardness strength with the addition of the volume fraction, where the highest impact energy for the volume fraction of durian skin fiber was 50%: 50%, 0.7738 J, and the highest impact value was 0.0096725 J/mm² and energy the lowest impact is 10%: 90%, 0.461 J. and the lowest impact price is 0.0057685 J/mm². So it can be concluded that the impact strength and hardness of the durian skin fiber composite increased with the increase in the volume fraction of the fiber.

Characterisation of Pectins extracted from Different Parts of Malaysian Durian Rinds

Durian rinds are a potential source of pectin. The rinds consist of the outer layer of the fruit which is semi-woody and thorny and the inner layer, which is creamy white. Pectin may be present in varying amounts in different parts of the rind. Previous studies only investigated pectin content from the inner part of the rinds. Therefore, it is essential to provide scientific data on the pectin yield from whole durian rinds (including the thorns). Particularly, this information can be useful when preparing durian rinds for pectin extraction. Hence, this study aims to examine and compare the yield and characteristics of pectin extracted from the inner part (W-I) and whole durian rind (W-H). The results indicate that the pectin yield from W-I was significantly higher (23.97%) than that obtained from W-H. The characterisation results show that both pectins have similar characteristics. The pectins extracted from W-I and W-H were high methoxyl pectin (HMP) with degrees of esterification (DE) at 53.13% and 51.42% respectively. The purity of these pectins was comparable to that of commercial pectins. These findings could pave the way in achieving sustainable pectin production at an industrial scale.

Ale beer containing free and immobilized Lactobacillus brevis, a potential delivery system for probiotics

Probiotics in ale beer may be attractive to health-conscious consumers. However, beer conditions may decrease probiotic viability. Powder produced from durian (Durio zibethinus) rind, a by-product that is currently unutilized, can be used for the immobilization of probiotics. MRS medium was incubated with Lactobacillus brevis and periodically sampled to obtain the growth curve. Ale beer with free L. brevis and cells immobilized in durian rind powder was produced and separately assessed during storage at 21 °C for 24 days. The physico-chemical parameters of both beers did not differ significantly. Durian rind powder conferred protection up to 12 days of storage with the immobilized cells in the beer having a significantly higher count than the free cells, which can be due to the acid detergent fiber content (19.67%). Free and immobilized cells remained viable with counts of 4.89 and 5.00 log CFU/mL of beer, respectively, at the end of the storage period. Both treatments had approximate counts of 5 log CFU/mL after 120 min in simulated gastric and intestinal fluids. The predominant bacterial species present at the end of storage were L. brevis and L. farciminis. This study suggests that ale beer could be a potential delivery system for free and immobilized probiotic bacteria. This is one of the few studies demonstrating the use of probiotic lactic acid bacteria in beer brewing. Graphical abstract

Durian Rind Micro Composter Model: A Case of Kampung Durian, Ngrogung, Ponorogo, Indonesia

The case of waste from durian rind in Ngrogung, Ngebel, Ponorogo, Indonesia increased significantly per year. Agglomerations and decomposition of durian rind surrounding agro park caused air pollution and bad view in park areas. The decomposition of durian rind is very important to reduce those impacts. The micro composter model in Kampung Durian consisted of three main components. The first component was drying area with cemented ground. The drying area was set to accommodate 1 t fresh durian rind per day. The materials come from surrounding areas of agro park. The second was a machine house with one ton material capacity per day. The third was a composter house consisted of composter tube and packing area. The result of the micro composter house showed a cleaning agglomeration of durian rind from Ngebel lake and surrounding areas. In addition, the model produced liquid organic fertilizer and compost. A cycle of composting was 30 d in the dry season. Amount 1 t of durian rind decomposition resulted of 100 L liquid organic fertilizers and 50 kg compost. The result of composter had a direct impact to control waste problems in Ngebel and surrounding areas.

In Situ Deposition of Green Silver Nanoparticles on Urinary Catheters under Photo-Irradiation for Antibacterial Properties

Urinary tract infections, especially catheter-associated urinary tract infections (CAUTIs), are the most common type of nosocomial infections. Patients with chronic indwelling urinary catheters have a higher risk of infection due to biofilm formation on the urinary catheter surface. Therefore, in this work, a novel, cost-effective antimicrobial urinary catheter was developed using green technology. Silver nanoparticles (AgNPs) synthesized from Mon Thong durian rind waste were used as an antimicrobial agent for the prevention of infection. Flavonoids, phenolic compounds, and glucose extracted from durian rind were used as a reducing agent to reduce the Ag+ dissolved in AgNO3 solution to form non-aggregated AgNPs under light irradiation. The AgNPs were simultaneously synthesized and coated on the inner and outer surfaces of silicone indwelling urinary catheters using the dip coating method. The results showed that the antimicrobial urinary catheter fabricated using a 0.3 mM AgNO3 concentration and 48 h coating time gave the highest antibacterial activity. The as-prepared spherical AgNPs with an average diameter of 9.1 ± 0.4 nm formed on catheter surfaces in a monolayer approximately 1.3 µm thick corresponding to a 0.712 mg/cm2 silver content. The AgNP layer was found to damage and almost completely inhibit the growth of Escherichia coli cells with antibacterial activity by 91%, equivalent to the commercial, high-price antimicrobial urinary catheter. The cumulative amount of silver released from the coated catheter through artificial urine over 10 days was about 0.040 µg/mL, which is less than the silver content that causes tissue and organ toxicity at 44 µg/mL. Thus, we concluded that the developed antimicrobial urinary catheter was useful in reducing the risk of infectious complications in patients with indwelling catheters.

Teknologi Pengomposan Limbah Kulit Durian Menggunakan EM4

Durian rind waste is a source of organic material that is easily found during the durian fruit season in South Kalimantan, where the potential abundance can reach 100 tons / day. If left unchecked, it will involve environmental problems such as garbage build-up, strong odors, and aesthetically disturbing views, so special care needs to be taken on the organic waste. Therefore, a solution is needed to overcome this problem by using durian rind waste as raw material for composting. The purpose of this study was to study how to apply the EM4 dose to the quality of durian skin waste compost. This study used a single complete randomized design (CRD) consisting of 6 preparations: s0 (0 mL EM4 / kg material), s1 (1 mL EM4 / kg material), s2 (1.5 mL EM4 / kg material), s3 (2 mL EM4 / kg material), s4 (2.5 mL EM4 / kg material), s5 (3 mL EM4 / kg material). The results showed that what was needed in the study with the help of 1 mL EM4 / kg material (S1), where the durian skin compost was in accordance with SNI on the pH parameters namely 7.48, C-organic 16.59%, total N 1.34%, moisture content 42.54%, temperature 30oC, and compost odor test with criteria not approved rotten.