MEDIA ALTERNATIF PERTUMBUHAN Staphylococcus aureus DARI BIJI DURIAN (Durio Zibethinus murr)

Media that is often used for bacterial growth is Nutrient agar. The high price incurred for the manufacture of instant media becomes a constraint so that innovation is needed that can reduce the cost of expenditure that is looking for alternative media from materials that are easily available. One of the natural ingredients that have a source of nutrients that can be used for bacterial growth of durian seeds that have a high carbohydrate content as a source of carbon. The objective of this research was to know the growth of Staphylococcus aureus bacteria on alternative medium of durian seed as substitution media of Nutrient agar. This research is laboratory experimental research, the sample used is durian seed with three concentrations of 200 g, 300 g, 400 g. The parameters observed were calculating total plate number and morphological form of Staphylococcus aureus bacteria growth. The results showed that the highest population on medium durian medium was the concentration of 200 g as much as 5.7 x 10-4 cfu and the lowest population at the concentration of 400 g was 3.5 x 10-3 cfu. While the population on the media Nutrient agar that is 7.7 x 10-6 cfu. Based on morphological observation of bacterial growth on durian seed medium, round shape, size 0.1 cm, white milk color, smooth surface, and convex elevation. The conclusion of this research is the growth of Staphylococcus aureus on alternative medium of durian seeds can be used as substitution media of Nutrient agar.

PRODUCTION AND CHARACTERIZATION OF AN Aspergillus niger GS1S6 PHYTASE CULTIVATED IN PHYTIC ACID-RICH AGRICULTURAL SUBSTRATES

In animal farming, improvement of growth performance through successful nutrient uptake and digestibility is critical. Phytases hydrolyze the anti-nutritive phytic acid present in grains to lesser derivatives and release the phosphorus trapped therein. Twenty-eight fungi obtained from poultry droppings, cereal-rich soils and garden soils were screened for phosphate solubilization and phytase production using Pikovskaya agar and phytase screening medium. Out of the fungi, 61% were positive for phytase producing abilities and the most proficient, isolate GS1S6 with a solubilization index of 121%, was identified as Aspergillus niger GS1S6. Optimum phytase production was achieved at a fermentation period of 120 h, pH 5.5, glucose, (NH4)2SO4 using 72 hour old fungal inoculum. Mineral supplementation of natural agricultural substrates enhanced phytase production (1000U/L) the most in milled sesame seed medium. The ~31-38 KDa partially purified and characterized enzyme demonstrated optimum activities at 55oC and pH 6.0, while cationic inclusions reduced phytase activities. The Km and Vmax were low (1.308 mM and 0.077 mM/mL/min) from Linear-weaver plot with increasing substrate concentration implying that A. niger GS1S6 phytase may efficiently mineralize phytic acid and therefore hold great prospect for its commercialization.

Optimization of growth of oyster mushroom mycelium (Pleurotus sp.) from Tasikmalaya on several kinds of cereal medium

Pleurotus sp. or oyster mushroom is one type of edible mushroom that contains essential nutrients for the human body. This mushroom has been widely cultivated in Indonesia, one of which is Pleurotus sp. from Tasikmalaya. The key to the success of oyster mushroom cultivation is the seeds and growing medium or baglog, while the factors that influence the quality of the seeds include the type of medium. This study aims to determine 1) the effect of the type of seed medium from the type of cereals used on the growth of mycelium Pleurotus sp. from Tasikmalaya, 2) determine the type of seed medium that has the best mycelium growth. This study uses an experimental method with a Completely Randomized Design (CRD). The parameters measured include the main parameters, namely the rate of growth of mycelium Pleurotus sp. from Tasikmalaya on the seed medium. Supporting parameters are the quality of mycelium growth in the seed medium, the proximate value of cereals used for the seed medium. The results of the analysis showed that the medium of cereals used as seeds ready for cultivation could affect the quality of the seeds produced. The seedling medium from milled corn has the best growth of mycelium.

Optimizing Culture Conditions by Statistical Approach to Enhance Production of Pectinase from Bacillus sp. Y1

It was found that Bacillus sp. Y1 could secrete alkaline pectinase with suitable enzyme system for powerful and fast degumming of ramie fiber. In this study, the medium components and fermentation conditions were optimized by some statistical methods including mixture design, fractional factorial design, central composite design and response surface methodology, and single factor method for enhancing the alkaline pectinase production. The optimized conditions for pectinase production were that the culture was shaken at 34°C for 60 h in 50 mL of medium containing 10.5% (w/v) carbon source (consisting of 3.8% starch, 4.2% wheat bran, and 2.5% sucrose), 0.37% (NH4)2SO4, 0.3% MgSO4, and 0.1% Tween-80, with initial pH 8.2 and inoculation amount of 1.3 mL (with the OD600 of the seed medium about 5.77). Using the optimizing conditions, the activities of polygalacturonate lyase (PGL) and polygalacturonase (PG) in fermentation liquor were increased to 2.00-fold and 3.44-fold, respectively, and the fermentation time shortened 12 hours (from 72 h to 60 h), which showed good application potential in degumming of ramie.

A Preliminary Study of Seeding Absence Detection Method for Drills on the Soil Surface of Cropland Based on Ultrasonic Wave without Soil Disturbance

Seeding absence detection is essential during seeding operation, since it affects the subsequent crop performance. Existing methods cannot detect the seeding absence position immediately after planting without soil disturbance. In this paper, a nondestructive detection method for finding out the seeding absence position of drills is put forward. It focuses on the echo energy reflected by the circle energy inside the tilled cropland soil, to which the sensor is attached directly on the soil surface, not on ultrasonic waves that penetrate the soil-seed medium below tilled soil. Firstly, the energy circle is used to analyze the sound field distribution characteristics of the sensor in cropland soil. According to the size difference of the seeding absence length value and energy circle diameter, the total energy for three different cases with eight steps for each case is discussed in detail, and in order to find the left and right boundary lines and the length value of seeding absence, a program is designed to help with calculating four base positions automatically. At last, the nondestructive detection method is evaluated by the experiments, and the results demonstrate that the proposed method is accurate, efficient, and convenient in finding the seeding absence position of drilling seeds on the soil surface without soil disturbance.

The Lobe-Type Agitator Parameters of the Seed-Metering Unit in the Seed-Fertilizer Drill Justification

Livestock products are the most important component of the actual total volume of farm produce. A reliable fodder base is required to increase their quantity and quality. The most part of the natural forage lands of the Republic of Kazakhstan is located in areas with insufficient water availability and low soil productivity. When they are used intensively, they are thinned and degraded. Their restoration and improving is possible if effective technologies and technical means are effected. However, the existing methods for improving and restoring forage lands and the technical means for their implementation are not adapted to the natural­climatic and agrobiological features of the zone of Central and Northern Kazakhstan, which feature insufficient moisture supply and low productivity.The main indicator of the effectiveness of the use of fodder crop seeds is their uniform distribution in the soil. However, most of them, due to their poor flowability, form dome structures of different sizes in front of seeding openings, which hinder the seeding process. To increase the flowability of such seeds, they are mixed with sand, sawdust, fertilizer and other materials. However, during the operation of seeders, the mixture is stratified according to its specific gravity. (The research purpose) is to develop a lobe­type agitator, which prevents the formation of a dome over seed holes. (Materials and methods) Theoretical studies have been carried out using the methods of classical and applied mechanics, as well as special sections of higher mathematics. (Results and discussion) The authors have experimentally confirmed the main parameters of the agitator and its resistance to movement in a seed medium. Experimental studies have been carried out on the basis of GOST 31345­2007. The studies have confirmed that a four­lobe agitator with an external radius of 0.06 m and an inclination angle to the plane of rotation 20°, mounted on the fertilizer drill SZS­2.0, has shown a total resistance of 3,042 kg with a design value of 2.925 kg. (Conclusions) The obtained results can be offered to the designers and developers of machines of the considered type when calculating and designing their working elements.

Kualitas Air Media Pemeliharaan Benih Udang Windu (Penaeus monodon Fabricius) dengan Sistem Budidaya yang Berbeda

Medium rearing of the P. monodon Fabricius seed at the hatcheries usually used closed system and without water changes during culture period, until certain time the water quality could deterioted. The purpose of this research was to understand the effects of recirculation system on the water qualities (total suspended solids, ammonia, ammonium, nitrite and dissolved oxygen) of tiger shrimp (P. monodon Fabricius) seed medium. This research was conducted in the hatchery of Marine Science of Diponegoro University at Teluk Awur. The research used experimental method with two treatments, recirculation and non-recirculation system. Concentrations of total suspended solids (TSS), ammonia, nitrite and dissolved oxygen (DO) were descriptive analyzed. Average concentration on recirculation system of TSS was 0,570 mg/L, ammonia was 0,039 mg/L, nitrite was 0,076 mg/L and DO was 6,00 mg/L. Average concentration on without recirculation system of TSS was 0,983 mg/L, ammonia was 0,09 mg/L, nitrite was 0,2 mg/L and DO was 3,86 mg/L. The resirculation rearing system was improve water quality on tiger shrimp seed medium. Keywords : Water Quality, Recirculation System, Tiger Shrimp (P. monodon Fabricius) Budidaya benih udang windu (P. monodon Fabricius) pada bak pembenihan umumnya menggunakan sistem tertutup dan air media tidak diganti, sehingga dalam waktu tertentu dapat terjadi penurunan kualitas air. Penelitian ini bertujuan untuk mengetahui perubahan kualitas air (MPT, amonia, amonium, nitrit dan DO) pada pemeliharaan benih udang windu (P. monodon Fabricius) dengan sistem resirkulasi dan tanpa resirkulasi. Penelitian dilakukan di Marine Center, Jurusan Ilmu Kelautan, Teluk Awur, Jepara. Metode penelitian yang digunakan adalah eksperimental dengan dua perlakuan yaitu penggunaan sistem resirkulasi dan tanpa resirkulasi. Data konsentrasi material padatan tersuspensi (MPT), amonia, nitrit, oksigen terlarut (DO), pH dan suhu selama penelitian dianalisis secara deskriptif. Hasil penelitian menunjukkan bahwa pada sistem resirkulasi konsentrasi rata – rata MPT 0,570 mg/L, amonia 0,039 mg/L, nitrit 0,076 mg/L dan DO 6,00 mg/L, sedangkan pada bak tanpa sistem resirkulasi konsentrasi rata – rata MPT 0,983 mg/L, amonia 0,09 mg/L, nitrit 0,2 mg/L dan DO 3,86 mg/L. Sistem resirkulasi mampu memperbaiki kualitas air media pemeliharaan benih udang windu. Kata kunci: Kualitas Air, Sistem Resirkulasi, Udang Windu (Pennaeus monodon Fabricius).

DERAJAT KEASAMAN (pH) VINEGAR DALAM MEDIA LIMBAH FERMENTASI BIJI KAKAO AKIBAT PENAMBAHAN KONSENTRASI Acetobacter aceti DAN WAKTU INKUBASI

<em>The study was aimed to identify the degree of acidity (pH) vinegar in a medium waste fermentation of cocoa beans due to the addition of Acetobacter aceti concentration and time of incubation.This research utilised two factor, factorial design with completely randomized design (CRD). Thefirst factor is the Acetobacter aceti consentration (10%, 13%, dan 16%). The second is the time of incubation (6, 8, dan 10 day). Results were analyzed by using SPSS program version 11 personal computer, two way ANOVA and multiple comparison test with significance level of 0,05.The results of analysis of variance showed that there were differences in the degree of acidity (pH) of vinegar in a medium waste fermentation of cocoa beans due to the addition of Acetobacter aceti concentration and time of incubation. While Duncan's test results showed the treatment inoculation 13% starter Acetobacter aceti with 6 days of incubation time significantly different from the other treatments with minimal pH is 2,02. So that these results meet the standards of vinegar. From these experiment we suggested that consentration of Acetobacter aceti and incubation period has effects in the degree of acidity (pH) vinegar in fermentation waste of cacao seed medium</em>